No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Assessment of Two Sheep Wool Residues from Textile Industry as Organic Fertilizer in Sunflower and Maize Cultivation
Abstract
Sustainable agricultural practices that enhance soil fertility and increase its capacity for carbon sequestration are increasingly needed. This study evaluates two types of sheep wool residues (SWRs)—carbonized (black wool, BW) and non-carbonized (white wool, WW) to enhance soil fertility and act as a N-source. The two SWRs were tested on two plant species, in two pot experiments: ornamental sunflower on soil mixtures with each of SWR types at different concentrations (0, 0.5, 1, and 2% w/w), and maize on BW- or WW-soil mixture (1% w/w) and supplementary N fertilization (0, 50, and 100% of recommended N rates). In sunflower, with the exception of WW at 2%, all SWRs-soil mixtures increased plant growth and biomass production. Lower SWRs concentrations enhanced the growth rate at an initial stage, and in general, BW provided optimal biomass, and flower yield. In maize, the SWRs (1%), especially BW, even without N-fertilization, were beneficial for plant physiological behavior and biomass production. High mineral N-fertilization (100% N with BW1%- or WW1%-soil mixture) resulted in lower biomass than the other BW-treatments. The results highlighted the efficacy of BW on biomass production for both species growing in a sandy-loam soil, and for maize, no need for further mineral N-fertilization.
... Wool pellet biodegradable nitrogenous organic amendment is derived as a secondary product from wool manufacturing processes (Abdallah et al. 2019;Sharma et al. 2019). Due to its role as a primary nutrient reservoir in the soil, the beneficial nutrient composition of wool pellets enhances both the productivity and yield of various plant species (Zheljazkov 2005). ...
... Although unprocessed wool may carry pathogens and requires risk mitigation (European Commission Regulation No 1069), it has been tested as a fertilizer with positive results on crop production. The application of sheep wool into the soil to aid plant growth and development has been studied extensively, with several studies reporting the beneficial effects of various wool wastes or wool residues on soil properties and fertility (Abdallah et al. 2019;Nustorova et al. 2006;Sharma et al. 2019;Zheljazkov 2005). Wool waste significantly affects the biological properties of soil (Lal et al. 2020). ...
... The utilization of organic by-products as potential fertilizers has been shown to enhance nutrient uptake by plants (Ordiales et al. 2016). Consequently, the application of by-products from the wool industry as organic fertilizers in horticulture has recently gained popularity (Abdallah et al. 2019;Górecki and Górecki 2010;Russell and Ireland 2016). One of the main properties of wool material is its biodegradability, providing a potential continuous nutrient supply in soils (Lal et al. 2020). ...
Pellets made from waste wool, typically sourced from sheep shearing residues generated by the textile or wool industry, have recently emerged as a promising alternative for plant nutrition. However, limited information is available on the impact of wool pellets (WP), applied at a dosage of 4 g per pot, on soil functioning, biological activity, plant physiology, and nutrient supply. A pot experiment was set up in a randomized block design with four replicates on sweet peppers ( Capsicum annuum L.). The effect of WP on permanganate-oxidizable carbon, fluorescein diacetate, and β-glucosidase enzyme activities were investigated in two soils differing in their soil organic matter (SOM) contents (low and high) and compared to the control and a reference N fertilizer solution. The nitrate and total nitrogen content of plants, the photosynthetic pigments, gas exchange intensity, shoot and root biomass, pepper fruit, and photosynthetic rate per total N-uptake were also examined. WP treatments (4 g per pot) increased soil biological activity in both soil types (with 0.58% and 1.84% soil organic matter, respectively) and significantly improved plant physiological parameters and N-use efficiency compared to the control and reference N fertilizer addition. Although the total N content in wool pellets was higher than in the mineral reference N-solution, this reference treatment served as a baseline dose allowing comparison with the N-supply intensity of the WP. WP significantly increased shoot biomass in both soil types, with a more pronounced effect in the low SOM soil due to faster mineralization and higher air capacity. In contrast, higher fruit was achieved in the high SOM soil. WP treatment increased N-uptake to 2.18 and 2.34 mg/week in low and high SOM, respectively. The research findings highlight wool pellets as a powerful alternative to inorganic fertilizers, offering a sustainable nutrient supply. Moreover, utilizing wool a by-product often considered waste as an organic fertilizer contributes to solving both economic and environmental challenges associated with wool disposal.
Graphic abstract
... So far, several studies have investigated the use of sheep wool fertilizer in alleviating the effects of salinity on plant growth, biomass, and certain physiological characteristics in Helianthus annuus L. and Zea mays L. (Abdallah et al. 2019), plant growth and yield in Capsicum annuum L. (Çetin Karaca et al. 2022), and vegetative growth, root development, nutrient content, and sugar quality characteristics in Beta vulgaris L. cv."Terranova" (Taskin 2024).However, no research has yet explored the effects of sheep wool fertilizer on L. officinalis seedlings under salt stress. In this context, this study introduces an innovative methodological approach by focusing specifically on L. officinalis, a plant with unique physiological and biochemical characteristics, and evaluating its response to sheep wool fertilizer under controlled salinity stress conditions. ...
... However, the application of sheep wool fertilizer, particularly at the SW-2 dosage, not only mitigates these negative effects but also enhances the overall photosynthetic performance, as evidenced by the highest values recorded for the contents of chl and car. In line with these findings, Abdallah et al. (2019) found that Khatami et al. 2022;Mehrabani 2023;El-Khadir et al. 2024a;Korkmaz and Çiçek 2024;Shala et al. 2024) reported that proline level in various Lavandula species increased in response to salt stress. For instance, El-Khadir et al. (2024a) found that salt stress caused a 43% reduction in RWC and a 60% increase in proline levels in L. dentata. ...
... Moreover, during the early growth phase, L. stoechas was found to be tolerant to moderate salty stress (< 50 mM)(Dadach et al. 2021).The substantial increase in PFW of L. officinalis under NaCl-90 with SW-2 and SW-4 suggests that these doses can mitigate salt stress, promoting improved growth outcomes. Previous studies showed similar benefits of sheep wool fertilizer, with the greatest PH achieved in Capsicum annuum (ÇetinKaraca et al. 2022), Helianthus annuus L.(Abdallah et al. 2019), Rubus fructicosus L.(Adi and Pacurar 2016), and Chlorophytum comosum ...
This study investigates the potential of sheep wool as an organic amendment to alleviate salinity stress and enhance the productivity of Lavandula officinalis in arid and semi-arid regions. A two-factor factorial design was employed under greenhouse conditions with five replications. The experiment tested varying levels of sheep wool fertilizer (SW) at concentrations of 0% (control), 0.5%, 1%, 2%, and 4%, alongside four salt concentrations: distilled water (control), 30 mM, 60 mM, and 90 mM NaCl. The study indicated that the application of sheep wool fertilizer significantly mitigated the adverse effects of NaCl on the growth, photosynthetic, and biochemical characteristics of L. officinalis. Increasing levels of sheep wool correlated with improved plant performance, while higher NaCl concentrations led to declines across all measured characteristics. Optimal performance was observed at the 2% SW treatment. Sheep wool fertilizer represents a promising strategy to enhance plant resilience in saline conditions. This study highlights the importance of optimizing sheep wool concentrations to maximize plant growth and stress tolerance. Future research should focus on investigating the long-term effects of different sheep wool doses and explore synergistic interactions with other organic amendments or bio-stimulants to improve agricultural sustainability in saline environments.
... Moreover, they can improve soil infiltration capacity and reduce surface runoff because they can slightly modify the soil, affecting the size and continuity of the soil pores, thereby increasing water movement [41]. However, due to the increased water percolation, they are not suitable for efficient rainwater conservation [94]. Conversely, high amounts of Na can affect soil salinity [41]. ...
... Conversely, high amounts of Na can affect soil salinity [41]. The residues can be used as fertilizers, especially for crops that require little fertilizer such as sunflower [94], although in the case of carbonized materials, the presence of sulphuric acid residues had a negative effect on seed germination [41] as well as bacterial community composition at concentrations of 2% or higher [96]. Scoured wool residues were tested by Gabryś and Fryczkowska [97], who highlighted the role of scoured wool in preventing water evaporation and facilitating water access for plants. ...
... Among crops, raw wool application to maize led to an average 25% increase in dry matter and a threefold increase in soil moisture content compared to the control group [40]. Even scoured wool positively influences crop yields with no need for further mineral N-fertilization [94]. Superheated wool hydrolysate proved to be an effective biostimulant on maize, especially for the growth of the foliar biomass [65]. ...
Agriculture significantly impacts the environment in terms of greenhouse gas emissions, soil nutrient depletion, water consumption, and pollution and waste produced by intensive farming. Wool has great potential and can be a valuable resource for agriculture due to its high nitrogen, carbon, and sulfur content and good water absorption and retention properties, benefiting soil carbon storage and fertility, as well as decreasing the risk of water contamination due to the slow decomposition and nitrogen release. This review aims to provide an overview of bio-based solutions that can benefit agroecosystems as a circular bioeconomy practice. Raw wool and wool hydrolysate are the most common applications, but also wool pellets, wool compost, and wool mats are interesting treatments for plant growing. Waste wool showed positive effects on soil fertility by primarily increasing nitrogen and sulfur content. Improved water retention capacity and microbial activity were also recorded in several studies. The use of wool as mulching is effective for weed control. Attention to the plant species tested aimed at identifying the most promising cultivations in terms of treatment efficiency, possibly lowering environmental impact on the agroecosystem. To eco-design and scale-up processes that strengthen the circular use of wool into widespread practices, further research should be encouraged in conjunction with environmental impact assessments and economic evaluations.
... Yet another fertilization experiment is interesting: Zheljazkov [58] described 14-week greenhouse experiment and 4-year field experiment, using wool and hair waste as fertilizer for basil, thorn apple and peppermint in greenhouse and for garden sage Table 2 Chemical composition of different raw wools, woollen products, some wool processing residues and wool compost nd no available data a Wool waste was composted with woodchips, dry grass clippings, horse stall waste, water hyacinth and food waste in four different piles. Results represent mixture of 60 combined samples (15 from each pile) b Results are given in mg/kg of dry matter Raw wool [52] Wool carpet [53] Acid wool hydrolysate [54] Wool scouring processing residue [55] Acid washing of scoured wool residue [55] Wool compost a [51] Dry in the field. Results suggest that both, wool and hair are good nutrient sources for high value crops for both greenhouse and field production. ...
... Yet another fertilization experiment is interesting: Zheljazkov [58] described 14-week greenhouse experiment and 4-year field experiment, using wool and hair waste as fertilizer for basil, thorn apple and peppermint in greenhouse and for garden sage Table 2 Chemical composition of different raw wools, woollen products, some wool processing residues and wool compost nd no available data a Wool waste was composted with woodchips, dry grass clippings, horse stall waste, water hyacinth and food waste in four different piles. Results represent mixture of 60 combined samples (15 from each pile) b Results are given in mg/kg of dry matter Raw wool [52] Wool carpet [53] Acid wool hydrolysate [54] Wool scouring processing residue [55] Acid washing of scoured wool residue [55] Wool compost a [51] Dry in the field. Results suggest that both, wool and hair are good nutrient sources for high value crops for both greenhouse and field production. ...
... Furthermore, prepared composts were used in experiments on the yields of chickpea and wheat. Addition of compost from waste wool with 10% (w/w) cattle slurry and 2% (w/w) of rock phosphate again showed the best results in wheat grain and straw production, as well as chickpea nodulation and grain and straw yield [61]. Composting, as an option of low quality or faecal-contaminated wool processing, especially in the parts of the world, where sheep are raised primarily for meat, was tested in Texas [55]. The aim of the study was to determine the proper mixture of wool waste with other biomass to produce a high-quality compost. ...
Sheep wool is keratin-rich by-product of sheep breeding and textile industry. Due to complex structure of keratin, this wastes are quite resistant to degradation and represent a serious environmental problem. Waste wool is often converted to different hydrolysates, which are mainly prepared by environmental unfriendly physico-chemical treatments, resulting in destruction of some amino acids and energy loss. Use of biotechnological approaches, such as microbial or enzymatic pretreatment, and composting, can significantly reduce the environmental impact, and produce useful products, such as fertilizers or substrates for biogas production, and high-added value products (peptides, amino acids and keratinolytic enzymes). In this review we compare different ways of waste wool processing, focused on biotechnological applications.
... Wool is also nitrogen-rich and takes approximately six months to decompose fully (Bradshaw & Hagen, 2022), making it a slow-release nutrient source that continuously supplies plants year-round. Furthermore, since 50% of wool's weight is carbon, incorporating it as a soil amendment offers an opportunity for carbon sequestration (Abdallah et al., 2019a). ...
... In this study, a significant increase in chlorophyll content was observed in lettuce crops with wool pellet addition, particularly in sandy soils, showing increases of over 80% compared to the control, indicating a favorable response in this substrate. These findings are consistent with previous studies that evaluated sheep wool residues (both carbonized and non-carbonized) in sunflower and maize, where soil-wool mixtures significantly increased chlorophyll content relative to the control (Abdallah et al., 2019a). This underscores the potential of wool residues as amendments to improve soil fertility and plant photosynthetic performance. ...
Since 2010, South America has been experiencing a prolonged megadrought, with a 40% reduction in annual rainfall, further intensified by climate change. This situation has led to a severe decline in water reserves, impacting agriculture and food security. To mitigate these effects, the adoption of sustainable agricultural practices, such as the use of sheep wool as an organic fertilizer, has been explored. This study evaluated the impact of wool pellets on lettuce growth and soil properties across different substrates. Lettuce seedlings were cultivated in 1 L pots with various soil types (sand, clay, and peat) and different wool pellet doses: a control group (C), a group with 5 g/L (W5), and one with 10 g/L (W10). Plant growth parameters and soil properties were monitored over a period of 120 days. The addition of wool pellets improved soil moisture retention and chemical properties, with moisture levels increasing by 3% to 25% compared to the control, particularly during dry periods. An increase in nitrate (41-54%) and potassium (10-53%) concentrations was observed in both soil and lettuce leaves (1.4 times) compared to the control, particularly in sandy and clay soils. Lettuce growth was significantly enhanced under the W10 treatment, which showed the highest increases in plant weight (2.5 times), leaf number (1.4 times), and height (1.4 times) compared to the control. Wool pellets may thus serve as an effective tool for optimizing soil management in low-fertility environments, promoting more sustained and resilient plant growth under variable water availability.
... In addition to non-woven and composite structures, there are other applications that can be given to textile waste. In Table 8, other opportunities for valorization of PCPIW are described, which can be applied in cement matrices, agriculture, energy production, enzyme production and packaging (Rajput et al., 2012;Hu et al., 2018;Nunes et al., 2018;Abdallah et al., 2019;Sadrolodabaee et al., 2021b;2021a;Rizal et al., 2021). ...
... In agriculture, the incorporation of waste is also advantageous. The addition of wool waste (PCPIW) to the soil during the cultivation of maize and sunflower increases the nitrogen content in the soil, replacing the use of fertilizers (Abdallah et al., 2019). ...
Each year, millions of tons of clothing are both produced and discarded, exerting a substantial impact on the environment and public health. Even when textile waste is disposed of in landfills, it persistently adds to pollution in the air, water, and soil. This review explores the diverse implications of textile waste, examining circular economy principles and highlighting opportunities for transforming textile waste into eco-friendly materials. This review highlights opportunities to repurpose textile waste into new products, aligning with the principles of a circular economy. The discussed materials, such as cotton, wool, polyester, nylon, and kevlar, can be utilized in various industries, including construction, non-woven, furniture, carpet, agriculture, and paper. The alternative materials presented offer excellent mechanical, thermal, and acoustic properties, providing sustainable alternatives in applications ranging from civil construction to insulation and structure reinforcement, minimizing environmental impact. Green material alternatives enhance cost-effectiveness in constructing eco-friendly buildings, reducing the need for extracting new raw materials and minimizing the carbon footprint. It is expected that research on opportunities for recovering textile waste will soon intensify, leading to the implementation of these new eco-friendly products.
... The two SWRs were compared at different concentrations (0, 0.5, 1, and 2% w/w); sunflower and corn were used as test crops. The results highlighted the efficacy of BW in biomass production without the need for further mineral N-fertilization for both species growing in sandy loam soil and maize (Abdallah et al. 2019b). Basak et al. (2020a), in a 2-year field study, compared the effect of different organic fertilizers (farm manure, vermicompost, and castor cake) on the yield and bioactivity of Ashwagandha. ...
... Organic matter is the source of nitrogen in the soil. All the reactions during the decomposition of organic compounds that reach the soil with organic fertilizers or plant residues by microorganisms and nitrogen gain and then reaching the atmosphere again constitute the nitrogen cycle (Chen et al. 2004;Basak et al. 2020aBasak et al. , 2020bAbdallah et al. 2019aAbdallah et al. , 2019b. ...
Soil is an essential element in sustainable agriculture. Improving soil properties and increasing soil fertility can be achieved by increasing the organic matter content of soils. Organic fertilizers are important in eliminating the negativity of the insufficiency of this component of soil. For this purpose, the study was carried out to determine the effect of manure made from sheep wool on some biochemical properties of soil with clay loam texture. Sheep wool manure (SWM) was added to the soil at rates of 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, and 5.0 t da⁻¹. Pepper was grown and some biochemical analyses were done after the harvest. According to the results of the research, pH, salinity, organic matter content, potassium (K), sodium (Na), iron (Fe), manganese (Mn), zinc (Zn), and boron (B) concentrations of the soils increased. The contents of other elements [phosphorus (P), calcium (Ca), magnesium (Mg), copper (Cu)] did not change in the study. In addition, the effects of sheep wool manure applied in increasing doses on some biological properties of the soil [urease (UEA), dehydrogenase (DEA), acid (ACPEA) and alkaline phosphatase (ALPEA), catalase (CEA) and arylsulfatase enzyme activity (ARSEA), basal soil respiration (BSR)] were statistically significant (p < .01). As the dose of sheep wool manure increases, the aeration of the soil and the water-holding capacity increase.
... Also, when BW (0.5, 1, and 2%) increased, stem diameter (mm) increased, while root biomass (g) and stem biomass (g) decreased. Besides, when WW (0.5, 1, and 2%) was applied, 1% application significantly increased the stem biomass (g) and root biomass (g), but 0.5 and 2% application decreased it significantly, but stem diameter (mm) was oppositely affected [10]. The water-soluble part of the total dry matter called brix or refractometer value is an important quality criterion in both production and quality control. ...
... In another direction, the SPAD was significantly increased when SWM was increased until 3.0 t da -1 application, while it decreased when SWM was increased after this dose. Similarly when sheep wool residue (SWR) (white or black) applications were increased in the soil, sunflower leaf chlorophyll content (SPAD) increased significantly [10]. ...
Sheep wool is an important organic fertilizer, friendly for environment, and rich in nitrogen, carbon, and sulfur. In this study, the sheep wool manure fertilizer doses (0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, and 5.0 t da-1) were applied to the root area of the seedlings in the soil to investigate its effect on the pepper plant growth under greenhouse condition. The seeds of the crop were initially pre-sowed in trays, and further, transplanted into the flowerpots. Following the treatment, the plant length, root length, shoot fresh weight, root fresh weight, shoot dry weight, root dry weight, fruit weight, fruit diameter, fruit height, number of fruits per plant, water-soluble dry matter, and SPAD value were measured. The results showed that some yield characteristics of pepper plants were significantly affected (p<0.01) with the increment in the doses of sheep wool manure applications. Generally, in the yield components of the pepper plant, the lowest and highest values were obtained from 5.0 t da-1 and 1.0 t da-1 of the manure application, respectively. It was concluded that the ideal dose of sheep wool manure for the crop is 1.0 - 2.0 t da-1.
... However, wool biodegrades slowly compared to other natural fibers like cotton, linen, and silk (Arshad et al. 2014). Various approaches were proposed to recycle wool wastes into different materials, including regenerated films , bioplastics (Fernández-d'Arlas 2019; Ramakrishnan et al. 2018), recycled protein fibers (Mu, Yu, and Yang 2023), and fertilizers (Abdallah et al. 2019). Wool is a natural protein fiber with a composition of up to 95% pure keratin by weight (Dias et al. 2022;Eslahi, Dadashian, and Nejad 2013), comprising abundant disulfide cross-linkages, salt bonds, hydrogen bonds, and other bonds that pack keratin molecules' α-helices and β-sheets into supercoiled polypeptide chains (Fernándezd'Arlas 2019). ...
This study aimed to establish a sustainable framework for the chemical upcycling of wool waste by evaluating previously reported keratin extraction methods based on the DOZN™ sustainability score, material cost efficiency, and keratin yield. The reduction reaction with L-cysteine was selected, achieving a yield of 28–36% and a relatively low DOZN™ aggregate score of 12, compared to oxidation and reduction with dithiothreitol, which scored 29 and 16, respectively. This method successfully extracted keratin from various wool sources, including wool yarns, dyed wool sweaters, and blended wool sweaters. SEM and FTIR deconvolution analyses confirmed that the extracted keratin from all sources exhibited similar microstructures. A proof-of-concept demonstration showed that these keratins can be used in formulation additives, adsorptive gels, and biodegradable paper alternatives, with a notable biodegradability of 91% weight loss in 44 days. This research provides a framework for rationally designing textile waste recycling processes, considering both feasible applications and sustainability as assessed by the DOZN™ tool, which evaluates alignment with the 12 principles of green chemistry. By leveraging this framework, future research and industry collaborations can explore expanded applications of keratin-based materials and adopt sustainable practices, enhancing the efficiency and environmental sustainability of textile recycling processes.
... The high predictive accuracy of the ANN between the wool pellet and CCI is likely explained by the fact that as wool material slowly decomposes in the soil, it serves as an effective, slow-releasing fertilizer, capable of functioning as a source of NPK nutrients and sulfur for a longer duration compared to conventional fertilizers (Abdallah et al. 2019). Furthermore, some authors have reported that the incorporation of wool waste into the soil increased the soil's NO 3 − and NH 4 + levels. ...
Monitoring the root system plays an important role in understanding plant physiological processes; however, its assessment using non-destructive methods remains challenging. Here, we evaluate the utility of root capacitance ( C R ) as a practical indicator of root function and its relationship to plant growth parameters in Capsicum annuum L. To improve the accuracy of root function assessment, we applied artificial neural networks (ANN) as a novel data evaluation approach, comparing its predictive performance against multiple linear regression (MLR). Across two soil types (sandy and sandy loam), we applied multiple treatments ranging from microbial inoculants to wool pellet and inorganic nitrogen sources primarily to test whether C R could detect differences in root activity and biomass production under different conditions. We measured root dry biomass, shoot dry biomass, and leaf N content, treating these variables as independent predictors in a statistical framework. Multiple linear regression (MLR) initially showed strong relationship between C R and both root and shoot biomass in sandy soil, and between C R and total plant N content in sandy loam. However, an ANN model consistently outperformed MLR in predicting C R from plant physiological parameters, as evidenced by lower mean absolute error (MAE) in all treatments. These findings confirm that C R correlates strongly with plant growth parameters and can reliably distinguish the effects of different soil amendments even those with markedly different nutrient-release profiles.
... These recycled fibers can be spun into yarn for use in woven or knitted fabrics or directly used in nonwoven materials. [140][141][142][143][144] Additionally, shredded fiber-based products are often referred to as "shoddy" fibers, commonly used in applications such as rugs, carpets, insulation, industrial fillings, and building materials. For instance, shredded textile waste can be compressed and heated into plates used for soundproofing and thermal insulation. ...
The world is on the verge of an impending crisis of textile waste, brought about as a result of the combined effects of a rising global population, burgeoning living standards and the shorter lifecycle of textile products. Textile recycling is the answer to help combat the enormous amount of waste created by the fashion and textile industries. While this is crucial to the growth of the textile waste recycling industry, practical and actionable interim solutions are still necessary. Textile waste is a significant stain on human life from both economic and environmental perspectives. From raw materials to finished products, clothing production from natural or synthetic sources can play a role in pollution and waste generation. This review article analyzes the economic and environmental implications of the fashion and textile industries. It assesses these waste recovery technologies and techniques, as well as the recycling at various stages of production and the use of the resulting recycled products. The recycling processes for textile waste have made some notable advances; however, some gaps remain unaddressed. Challenges include multi-scaler industrialization, waste treatment and separation processes, as well as waste contamination, such as mixed chemicals. And greater awareness is needed among consumers of the value of fiber-to-fiber recycling, as technological progress in this field has not matched its need. On the whole, this article is a good resource to gain a sense of the current landscape of recycling and recovery in textiles, clothing, and fashion.
... They cause no soil pollution, water contamination, or soil degradation while protecting biodiversity and preventing hazardous compounds from infiltrating groundwater or soil surface [15]. Many studies have revealed that wool manure or fertilizer made from waste wool has many benefits for plant growth and yield [27][28][29][30], organic farming [31][32][33] and improving soil properties [34,35]. Previous research has shown that the application of wool pellets resulted in substantial increases in the yield and quality of both spinach and tomato crops compared to control and standard fertilization practices. ...
Soil salinity is a pervasive challenge in agricultural regions, significantly impacting plant growth and productivity. Addressing the adverse implications of soil salinization and capitalizing on organic waste resources has the potential to yield substantial advancements in the agricultural sector. This study examined the influence of varying levels of wool pellets (0, 1%, 2%, and 4%) and salt (0, 25, 50, and 100 mM) on the physiological and biochemical properties of soybean (Glycine max L.). The findings revealed that compared to the control group, at a 4% application rate, plant length decreased by 20%, while stem dry weight, root length and weight showed no significant differences up to a 2% application. Compared to the control treatment, the 4% application rate resulted in an increase of 6% in leaf temperature, 55% in NBI, 12% in chlorophyll content, and 10% in MDA activity. Conversely, the TAA, TPC, and carotenoid content decreased by 55%, 51%, and 81%, respectively. Salt applications led to reductions in most studied morphological parameters, except for root properties. Compared to the control, plant length, stem fresh weight, and stem dry weight decreased by 14%, 22%, and 14%, respectively, while root length, root fresh weight, and root dry weight increased by 18%, 33%, and 50%, respectively.
... It has been clearly understood that the application of hydrolysate at increasing levels to the soil stimulates the growth of lettuce, spinach, and radish plants. Similarly, in a few previous studies, positive effects of hydrolysate applications have been observed in various plants (Abdallah et al. 2019;Akca et al. 2023;Broda et al. 2023). The hydrolysate's impact on plant growth can mainly be attributed to the amino acids it contains, such as tyrosine, glycine, valine, and methionine. ...
Sheep wool (SW) serves as a slow-release organic fertilizer, and its effectiveness can be enhanced through alkaline hydrolysis to break down keratin. The resulting keratin hydrolysate can support plant growth and improve mineral nutrition. Keratin hydrolysate obtained from sheep wool via the alkaline hydrolysis method was applied to lettuce, spinach, and radish plants at levels of 0, 0.5, 1.0, 1.5, 2.0, and 3.0 mL kg − 1 . Before starting the experiment, the molecular and chemical structure of sheep wool hydrolysate (SWH) was determined using Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy and Raman Spectroscopy. At the end of the study, the effects of SWH on plant growth and mineral nutrition were determined. Based on the experimental results, several amino acids, including alanine, glycine, tryptophan, valine, and methionine, were identified in the composition of the hydrolysate. Treatments with SWH significantly enhanced the growth of lettuce, spinach, and radish plants. Furthermore, these treatments led to a notable increase in the total nitrogen (N) concentration in the plants. Specifically, the calcium (Ca), magnesium (Mg), and iron (Fe) concentrations significantly increased in both lettuce and spinach. Additionally, SWH treatments elevated the zinc (Zn) concentration in radish tubers and the manganese concentration in lettuce plants. The copper (Cu) concentration in the plants also rose significantly following SWH treatments. The use of keratin hydrolysate derived from SW through the alkaline hydrolysis method demonstrates its potential to promote plant growth, emphasizing its significance in waste recovery and its transformation into a valuable resource.
... New application areas have been explored for this wool, and several new products have been developed. The highest importance has gained thermal and acoustic insulating materials, geotextiles and fertilisers [14][15][16][17][18][19][20]. Applying wool as mulch is the next possible option. ...
The application of wool as mulch in strawberry cultivation was analysed to find a so-lution for the rational use of wool from mountain sheep. In the plantation, the experimental plots mulched with wool, straw and bark were appointed. The plots were monitored during the ex-periment, while the soil temperature and moisture content were measured. The data collected in two-hour intervals were analysed, taking into account air temperature and falls registered in the local meteorological station. Additionally, the progress of mulch biodegradation was tracked. The changes in the wool morphology that occurred by biodegradation were observed during micro-scopic examinations using the Scanning Electron Microscope (SEM). It was stated that wool mulch plays an essential role in thermoregulation of the soil surface, prevents the overheating of the soil during the summer heat and protects it against excessive cooling during cold nights. The wool mulch minimises the fluctuations between the soil’s day and night temperature. The fluctuations do not exceed 2 - 3 degrees on hot summer days, which are five times smaller than for the control plot. The wool retains large amounts of rainwater several times its weight. The water is then slowly released, providing the growing plants a moist environment during a longer rainless pe-riod. Moreover, wool is difficult to biodegrade and maintain its properties for a long time, lasting longer than one vegetation season. Compared to straw and bark, the temperature fluctuations recorded for wool are two times smaller, and its effectiveness in water management is consid-erably better. The beneficial impact of the wool mulch ensuring favourable conditions for strawberry growth was explained by the specific wool structure and its unique properties.
... New application areas have been explored for this wool, and several new products have been developed. The highest importance in these new areas is thermal and acoustic insulating materials, geotextiles, and fertilisers [14][15][16][17][18][19][20]. Applying wool as mulch is the next possible option. ...
The application of wool as mulch in strawberry cultivation was analysed to find a solution for the rational use of wool from mountain sheep. In the plantation, the experimental plots mulched with wool, straw, and bark were appointed. The plots were monitored during the experiment, while the soil temperature and moisture content were measured. The data collected in two-hour intervals were analysed, taking into account air temperature and falls registered in the local meteorological station. Additionally, the progress of mulch biodegradation was tracked. The changes in the wool morphology that occurred by biodegradation were observed during microscopic examinations using the Scanning Electron Microscope (SEM). It was stated that wool mulch plays an essential role in thermoregulation of the soil surface, prevents the overheating of the soil during the summer heat, and protects soil against excessive cooling during cold nights. The wool mulch minimizes the fluctuations between the soil’s day and night temperature. The fluctuations do not exceed 2–3 degrees on hot summer days, which are five times smaller than for the control plot. The wool retains large amounts of rainwater several times its weight. The water is then slowly released, providing the growing plants with a moist environment during a longer rainless period. Moreover, wool is difficult to biodegrade and maintains its properties for a long time, lasting longer than one vegetation season. Compared to straw and bark, the temperature fluctuations recorded for wool are two times smaller, and its effectiveness in water management is considerably better. The beneficial impact of the wool mulch ensuring favourable conditions for strawberry growth was explained by the specific wool structure and its unique properties.
... As a result, it is recommended to use the slurry as an inoculum with a combination of 10% dry weight and 2% rock phosphate for effective composting of persistent materials such as wool waste. 138 Composting is an increasingly popular option for handling low-grade or fecal-contaminated wool, especially in regions of the world where sheep are raised primarily for meat production. This ecological and cost-effective method has been tested with great success in Texas, helping to reduce the amount of waste that ends up in landfills. ...
The world has been facing a growing crisis in textile waste due to global population growth and improved living conditions, combined with a decrease in the life cycles of textile products. Textile recycling is one of the key aspects for reducing the massive waste problem generated by the fashion and textile industries. Despite the need to develop textile waste recycling industries, acceptable practical interim measures still need to be taken. Textile waste can affect people’s lives economically and environmentally. Producing apparel from natural or synthetic origin can produce pollutants and waste at each stage. In this review article, the effects of the fashion and textile industry have been studied from economic and environmental perspectives. The available technologies and methods for waste recovery and recycling at each stage have been studied, and the uses of products after recycling have been systematically investigated. Despite all the progress made in the waste recycling processes of the fashion industry, many deficiencies and challenges still need to be addressed. Among the most critical challenges are the large scale of industries, the problems of collecting and classifying waste materials, and the presence of contaminants including blends and chemicals. There is also need for more awareness among consumers about the importance of fiber-to-fiber recycling processes, because to date the progress in this field is out of proportion to its necessity. Overall, this article is a valuable resource for anyone interested in understanding the current state of recycling and recovery in the textiles, garment, and fashion industries.
... Only sheep wool fibers of high quality are utilized by the textile industry, while unprocessed sheep wool fibers often regrettably become waste at loading depots [1]. Nontextile sheep wool has found its place already as an insulating material [2], building additive [3,4], keratin source [5], or fertilizer [6,7]. However, still new applications are required, therefore ionizing radiation modifications can be applied [8,9]. ...
Latvian Darkhead (LD) is a local sheep breed and a genetic resource in Latvia. Preservation and development of the sheep population in the local region is important for the recultivation of fields, it serves as a source for export and local use, as well as waste wool can be applied for developing new products, for example, sorbents for volatile organic pollutants. Therefore, investigation of the sorption properties of the LD sheep wool fibers is under interest. In addition, modification options of the wool for improvement of properties are viewed. Therefore, in the present work, sheep wool fibers as well as accelerated electron-irradiated fibers are analyzed and compared. Fourier transform infrared (FTIR) spectrometry is applied to develop the sorption testing system of volatile organic compounds. An analytical system consisting of a volatile organic compound source, sheep wool filter, and FTIR spectrometry cell is tested and applied for analysis of wool sorption properties for acetone molecules. Registration of the FTIR spectra was performed within the range of 600-4000 cm-1, in the nitrogen flow of about 150mL/min. FTIR analysis shows, that the accelerated electron irradiated sheep wool fibers absorb acetone of about 33% more than non-irradiated fibers. The obtained results will be used for developing recommendations for filter producers to fabricate filter components containing LD sheep wool fibers.
... However, as unprocessed (greasy) wool may be contaminated with pathogens (e.g., Listeria monocytogenes and Salmonella spp.) [15], causing transmissible diseases, it must be subject to the risk mitigation measures provided for in Regulation (EC) No 1069/2009 [11]. Sheep wool has been tested as a fertilizer in various forms, e.g., washed wool fibers, wool residues from industrial washing, and hydrolyzed wool [16][17][18][19][20][21][22], with positive results on crop productions and soil moisture retention. Bradshaw and Hagen [23] reported how wool pellets are a viable alternative to commercial fertilizers for organic vegetable production as they showed very similar growth and mineral uptake as compared to commercial fertilizers. ...
The production of wool is an economic burden and an issue for sheep breeders in many countries of the European Union because shorn greasy wool is defined as an animal byproduct (category 3) and must be sent to landfill as a special waste if not addressed in the textile supply chain. Nevertheless, wool is an important source of nitrogen, with high potential as agricultural renewable and sustainable organic fertilizer. To apply wool to soil, any contamination from harmful bacteria (e.g., Listeria monocytogenes and Salmonella spp.) should be excluded. In this study, we developed sheep wool pellets to test their suitability for use as an organic fertilizer. Wool was rich in N (12% of dry material) and was mixed to spruce sawdust at sawdust: wool ratios of at 2:1; 1:1 (v/v) to increase soil organic carbon. Despite the different mix of wool and sawdust, pellets were similar in size (diameter and length), and the content of the elements suited the requirements of fertilizers and did not present harmful bacteria after pelletization. Therefore, wool pellets may represent a feasible solution to provide sheep wool with an added value, introducing it in a circular economy process. However, further study is needed to test the effects of the produced fertilizing pellets in real cropping systems.
... The results were compiled in Table 16, where, for each waste type described in Section 4.1, a set of possible secondary raw materials and applications is identified and referenced. Bio-based chemicals, pharmaceuticals, rubber, and plastics [85][86][87][88] Fertilizers, biochar, and cellulose acetate Textile and textile products [34] Textile recycling Liquid biofuel/energy [89][90][91] Syngas, bio-oil, biogas, bio-alcohol, hydrogen, biodiesel, and electricity ...
The development of a resilient and circular bio-based economy is of paramount importance, notably in the EU, where current climate policies and evolving regulations strongly demand more sustainable practices, impacting monitoring and reporting, as well as the deployment of novel valorization routes for byproducts and waste streams. In this context, with the aim of assessing the current state of the European bio-based economy, a comprehensive analysis based on socio-environmental, socioeconomic, and technical indicators was carried out on major sectors, namely textiles, woodworking, pulp and paper, bio-based chemicals and materials, liquid biofuels, and bio-based electricity. Each sector was evaluated with respect to its main biological raw materials, and a methodology is proposed to link their geographical origin (inside or outside the EU), import shares, and internal production with socio-environmental impacts, based on official databases and indexes. Socioeconomic data (turnover and employment) and technical data (average bio-based content within the main products of the sector) were also considered for the analyses, allowing a multi-angle comparison between sectors and the identification of barriers and opportunities for future developments. Finally, a quantitative and qualitative overview of non-hazardous biogenic waste streams generated in the EU is presented, and opportunities for their valorization and reintegration into the EU bio-based economy are discussed. As a result of this analysis, beyond enabling the assessment of each sector within the bio-based economy, along with the assignment of values for comparison, the implementation of this evaluation facilitated the identification of improvement pathways, which were consolidated into a set of proposals.
... The greatest importance gained as an insulating material designed for building industry (Dénes, Florea, and Manea 2019;Korjenic et al. 2015;Parlato, Cuomo, and Porto 2022;Rubino et al. 2021;Zach et al. 2012), sound-absorbing materials (Broda and Bączek 2019;Broda et al. 2023;Kicińska-Jakubowska et al. 2023;Kobiela-Mendrek et al. 2020;Mirjalili and Mohammad-Shahi 2012;Patnaik et al. 2015), geotextiles (Broda and Gawlowski 2020;Broda et al. 2017;Marczak, Lejcus, and Misiewicz 2020), and oil or heavy metals absorbing materials (Laurie and Barraclough 2008;Naik et al. 2010;Radetic et al. 2008;Saha et al. 2019). Moreover, wool is used as mulching material and fertilizers in organic agriculture, horticulture, and forestry (Abdallah et al. 2019;Bernacka, Święcicka, and Naworska 2015;Bhavsar et al. 2021;Böhme et al. 2012;Broda et al. 2023;Hustvedt, Meier, and Waliczek 2016;Sharma, Sahoo, and Chand 2019;Zheljazkov 2005;Zheljazkov et al. 2009) or as reinforcement of soil, clay or concrete (Aymerich, Fenu, and Meloni 2012;Galán-Marín, Rivera-Gómez, and Petric-Gray 2010). ...
The wool of several native breeds raised in Polish mountains and foothills was examined. The content of natural contaminants and basic wool parameters, thickness and length was determined during investigations. In addition, the wool morphology was analyzed by electron microscopic observations. It was revealed, that the fleece of sheep for all breeds is a mixed type, which is formed from more delicate, thinner and shorter wool with the addition of thicker and longer guarded hairs. In the fraction of guarded hairs, a high amount of medullated fibers and kemp occur. Comparing the wool obtained from sheep of white and colored varieties, it is stated that wool has similar characteristics. Additionally, it was found that similar parameters exhibit wool obtained from sheep of the same breed originating from various flocks raised in different locations. Analyzing the wool characteristics, the possibilities for its potential application were indicated.
... Various benefits of applying waste wool to the soil have been reported in previous studies. Wasted wool applied to the soil increases soil water holding capacity and traps pollutants such as pesticides (Hargreaves 2017;Haque and Naebe 2022), the total porosity, water use efficiency, macroaggregates and aggregate stability of the soil (Kadam et al. 2014;Abdallah et al. 2019;Karaca et al. 2023). Sheep wool can be used as a mulching material (Hempe 2014;Sharma et al. 2019) and as a slow-release fertilizer (Waliczek et al. 2013). ...
Keratin-rich materials, such as waste sheep wool, possess a rich mineral element composition but exhibit challenges in natural decomposition. Consequently, most of these waste materials are either incinerated or disposed of in landfills, leading to environmental concerns. However, these wastes have the potential to serve as effective fertilizers and soil conditioners. They can be utilized directly or undergo various processes for application in agricultural production. The present study aimed to investigate the effects of waste sheep wool and its alkaline hydrolysate on the growth of sugar beet shoots and roots, nutrient concentrations, and sugar quality parameters. Shoot and root samples were collected at two-week intervals throughout the root development stage until harvest. Temporal changes in leaf mineral element concentrations and sugar quality parameters of the sugar beet roots were determined. Waste sheep wool treatment significantly increased the shoot and root yield of sugar beet. Compared to control, nitrogen, calcium, and magnesium concentrations in the leaves were increased in the fourth sampling. However, the treatments resulted in a significant reduction in iron concentrations in the leaves, as well as sugar content and white sugar content in the roots, particularly towards the harvest period. However, the significant increase in shoot and root growth, nitrogen, calcium, and magnesium in leaves showed that these wastes will provide fertilizer economy in sugar beet production. It would be beneficial to reconfirm the results of this study on different sugarbeet varieties and in field conditions with decreasing standard chemical fertilizer doses.
... During week 1 to 4 composting process, the pH values increased and decreased in weeks 4 to 7. Joshi et al. 20 who compost chest nut burr/leaf, litter and poultry manure reported similar observations. Abdallah et al. 21 found that it may be due to digestion of keratinaceous waste. At pH 6 to 9 and at 30-50°C, most keratinases are optimally active, bacteria producing keratinases by exhibiting a wide pH (5.8-11) 22 . ...
Biodegradation of livestock processing waste is one of the more cost-effective, ecologically safe recycling methods that may preserve nutritional content and key amino acids useful in animal feed production. Here, we determined the biodegrading potentials of nonconventional feedstuffs using a combination of bacteria (Bacillus subtilis) and fungi (Fusarium sp.). Five nonconventional feed types (feather meal, hair waste, egg membranes, horn hoof and horn) were selected and replicated in a 10 L plastic biocomposter for 7 weeks and observed for degradation by measuring changes in total organic carbon, temperature, phosphorus, potassium, pH, microbial counts and rate of degradation. Bacteria and fungi were inoculated inside the substrate after isolation and incubation. The effects of physicochemical and microbial counts were assessed. The biodegradability and optimal activity were observed. From the results, physico-parameters measured during the 7 weeks showed significant differences (P <0.05) between substrates. The highest rate of decomposition, temperature, pH levels, total organic carbon, and total bacteria counts were recorded in feather meal, egg membrane, and hair waste. The weekly study showed that feather meal (68.79%, decompose faster than cow hoof (18.72%) egg membrane (60.89%) hair waste (62.82%) and cow horn (32.31%) during bio-composting. This finding has potential application in the treatment process of keratin wastes.
... Methods of processing waste wool into usable fertilizers through hydrolysis have been developed to improve the bioavailability of nutrients, product handling, and remove the pollutants contained in processed wool waste [21,22]. Numerous field trials in African and European sites have evaluated the effects of raw wool [19,[23][24][25][26], processed wool pellets [27], and wool waste byproducts [20,22,[28][29][30] on the growth and productivity of field and vegetable crops. Overall, the application of wool at various rates has had beneficial effects on soil quality and plant performance with few, if any, negative side effects. ...
The maintenance of optimum mineral nutrient fertility is a limiting factor in organic vegetable systems, with many growers resorting to applications of off-farm commercial fertilizer inputs. In this study, pelleted sheep’s wool was compared against a standard commercial fertilizer product for effects on productivity and plant growth in spinach and tomato. Two rates of wool pellets were applied; one was standardized to the nitrogen inputs of the ‘grower standard’ commercial treatment, and a second higher rate which was suggested by the pellet manufacturer with about 2.5 times the nitrogen content. Overall, few differences were observed among the fertilized treatments. Crop yield for both tomato and spinach generally increased with increasing fertility application, with no differences between commercial and wool pellet fertilizers applied at the same rate of nitrogen. The uptake of mineral nutrients in spinach plant tissues differed for K, Mg, P, S, B, and Ca, but there was no general trend that could be attributed to a particular treatment. Tomato fruit quality was the same for all treatments, but non-fertilized fruit had lower total polyphenols than the highest-fertility treatment. Overall, wool pellets performed very similarly to commercial organic fertilizer for both crops and could be a promising alternative that may open up opportunities for greater integration of plant and animal systems on diversified farms.
... Furthermore, the effect of these composts on yields of chickpea and wheat was tested. Addition of the compost produced from waste wool with 10% (w/w) cattle slurry and 2% (w/w) of rock phosphate showed the best results with regard to wheat grain and straw production, as well as chickpea nodulation and grain and straw yield [97]. Composting is also an option for processing low quality or fecal-contaminated wool, especially in the parts of the world where sheep are raised primarily for meat, and has been tested in Texas [100]. ...
Post-consumer bio-based textile wastes are any type of garment or household article made from manufactured bio-based textiles that the owner no longer needs and decides to discard. According to the hierarchy of waste management, post-consumer textile waste should be organically recycled. However, there is still a problem with the implementation of selective collection of textile waste followed by sorting, which would prepare the waste for organic recycling. A technically achievable strategy for sorted textile waste materials consisting of only one type of fiber material, multi-material textiles are a problem for recycling purposes. Waste textiles are composed of different materials, including natural as well as synthetic non-cellulosic fibers, making bioprocessing difficult. Various strategies for recovery of valuable polymers or monomers from textile waste, including concentrated and dilute acid hydrolysis, ionic liquids as well as enzymatic hydrolysis, have been discussed. One possible process for fiber recycling is fiber recovery. Fiber reclamation is extraction of fibers from textile waste and their reuse. To ensure that organic recycling is effective and that the degradation products of textile waste do not limit the quality and quantity of organic recycling products, bio-based textile waste should be biodegradable and compostable. Although waste textiles comprising a synthetic polymers fractions are considered a threat to the environment. However, their biodegradable part has great potential for production of biological products (e.g., ethanol and biogas, enzyme synthesis). A bio-based textile waste management system should promote the development and application of novel recycling techniques, such as further development of biochemical recycling processes and the textile waste should be preceded by recovery of non-biodegradable polymers to avoid contaminating the bioproducts with nano and microplastics.
... In this situation in recent years, several ideas of processing local wool with various unconventional techniques or using it in unusual way have been examined. For this purpose, several studies on using wool products in civil engineering as soil reinforcement and erosion protection [Hejazi et al. 2012, Broda et al. 2018, in agriculture as fertilizers [Zheljazkov et al. 2009, Zoccola et al. 2015, Abdallah et al. 2019 as well in the construction industry as thermal and acoustic insulating materials [Corscaden et al. 2014, Broda and Bączek 2020] were performed. Moreover, a few research projects on using local wool were implemented. ...
... The greatest importance gained as an insulating material designed for building industry (Dénes, Florea, and Manea 2019;Korjenic et al. 2015;Parlato, Cuomo, and Porto 2022;Rubino et al. 2021;Zach et al. 2012), sound-absorbing materials (Broda and Bączek 2019;Broda et al. 2023;Kicińska-Jakubowska et al. 2023;Kobiela-Mendrek et al. 2020;Mirjalili and Mohammad-Shahi 2012;Patnaik et al. 2015), geotextiles (Broda and Gawlowski 2020;Broda et al. 2017;Marczak, Lejcus, and Misiewicz 2020), and oil or heavy metals absorbing materials (Laurie and Barraclough 2008;Naik et al. 2010;Radetic et al. 2008;Saha et al. 2019). Moreover, wool is used as mulching material and fertilizers in organic agriculture, horticulture, and forestry (Abdallah et al. 2019;Bernacka, Święcicka, and Naworska 2015;Bhavsar et al. 2021;Böhme et al. 2012;Broda et al. 2023;Hustvedt, Meier, and Waliczek 2016;Sharma, Sahoo, and Chand 2019;Zheljazkov 2005;Zheljazkov et al. 2009) or as reinforcement of soil, clay or concrete (Aymerich, Fenu, and Meloni 2012;Galán-Marín, Rivera-Gómez, and Petric-Gray 2010). ...
The aim of the study was exploration of the properties of wool derived from sheep reared in Poland. Twenty-nine breeds of sheep diverse from the type of farming, e.g. for meat, dual-purpose breeds for wool-milk, and versatile wool are bred in Poland, but only few of them have uniform wool. Because there is a lack of data determining quality and quantity of Polish wool, the wool-based textile industry in Poland uses mainly imported raw material. Wool quality has an impact on processing efficiency and determines possibility of its further use. In order to assess the wool quality from the local sheep breeds (Polish Merino, Olkuska, Żelaźnieńska, Polish Lowland Sheep), fiber parameters were evaluated: average fiber diameter, length, curvature, and comfort factor. The wool was subjected to microscopic analysis and color examination. Results of the study showed that wool from the above-mentioned sheep breeds varies greatly in terms of quality. The obtained data helps fill the information gap on Polish wool.
... Another application of textile fibers for improving oil carbon content was described by Ugolini and coworkers (Abdallah et al. 2019). The authors underlined the efficiency of wool addition on soil for the cultivation of sunflower and corn crops. ...
The textile industry is a large source of pollution due to the production of raw materials (natural and synthetic fibers), preparation and finishing processes, as well as due to textile waste, especially the post-consumer waste. This paper is an attempt to change the
perception concerning such waste. In the context of circular economy, textile waste has to be conceived as a source for carbon and energy. A new attitude is compulsory due to the increase of post-consumer waste quantity since the volume of textile consumption
has lately increased. Fast fashion cycle and cheaper textile products having a shorter lifetime led to an increase of the quantity of post-consumer textile waste. Demands for pollution reduction generated the concern to upcycle the textile waste in order to
recover, at least partially, the materials as well as the energy consumed for their manufacture, reducing accordingly the carbon and water footprints of these products,. The scarcity of raw materials and of fossil fuels, the high environmental impact of the
simple disposal of waste, imposed a new policy regarding the transformation of the linear economy which characterizes today’s textile industry into a circular one, leading to a lower environmental impact. This involves the valorization of post-consumer waste by recycling or at least by a partial recovery of the materials and energy spent for the manufacture of these products. A good management of post-consumer textile waste is mandatory for attaining a zero waste target. Some good practices in the field are presented by this paper.
... Nutrients absorbed and utilized by plants are the key process of the material cycle of the ecosystem (Mu and Geng 2015). Nutrients play specific roles in plant physiological response, growth and development, system evolution, and ecosystem function, etc. (Du et al. 2011;Abdallah et al. 2019;Cuevas and Quiroz 2019). After the completion of the plant life cycle, nutrients will be returned to the soil through decomposition, and will be absorbed and utilized by plants again to realize the biogeochemical cycle of elements (Cabeza et al. 2019;Hui et al. 2019). ...
The aim of the study was to investigate the effects of a special organic fertilizer (SOF, with common organic fertilizer (COF) as the carrier and Na+ as well) on the growth performance of Haloxylon ammodendron, and soil properties in desert regions of China. All fertilization treatments were applied to seedlings in the nursery in open field in Alashan Right Banner (ARB, severe arid area) and Hangjin Banner (HB, mild arid area) of Inner Mongolia (plants were not used for afforestation), and unfertilized 1-year-old plants cultivated in Minqin (MQ, moderate arid area) of Gansu province were selected and applied SOF for afforestation in ARB, HB, and MQ, respectively. The results (take ARB for example) indicated that SOF significantly increased plant height (PH) by 52.2 and 37.6%, main root length (MRL) by 42.6 and 22.8%, and dry weight (DW) of whole plant by 142.4 and 104.6%, respectively, over the CK and COF treatments in the nursery. SOF also significantly mitigated deleterious impacts of drought stress on the growth of H. ammodendron and enhanced soil properties in afforestation, where it increased survival rate (SR) by 50.6% and 28.9%, PH by 17.2% and 12.1%, MRL by 43.5% and 44.8%, and DW by 110.3% and 54.7%, respectively, compared with CK and COF treatments. Furthermore, soil organic matter (SOM) in SOF treatment was significantly increased by 210 and 6%, and no significant effect on Na+ content in root zone soil was observed in afforestation. The effects of SOF on H. ammodendron and soil properties were more remarkable in MQ and HB than in ARB. We conclude that SOF provide efficient nutrients for H. ammodendron, and the Na+ released by SOF can be utilized by H. ammodendron in time, and will not be released to soil in large quantities, which initiates a new method to restore degraded vegetations in desert regions of China.
This study investigates the effects of hydrolyzed keratin (HK) on the growth and Ca and Mg uptake of lettuce plants under natural and light-emitting diode (LED) lighting conditions in cocopeat and soil environments. Lettuce plants were grown under natural light in cocopeat and soil, and simultaneously under blue (B), blue + far-red (B + FR), red (R), R + B, R + FR, R + B + FR, and white (W) light conditions. The fertilizer treatments consisted of control, HK, Ca + Mg, and HK + Ca + Mg. The highest fresh and dry weights of lettuce plants were observed with HK treatment in cocopeat, and HK + Ca + Mg treatment in soil. Among different LED light sources, the highest fresh and dry weights were recorded under the R light, followed by R + B + FR, R + B, and W, with the weakest growth observed under B + FR, R + FR, and B. Regardless of light source, HK and Ca + Mg treatments improved fresh and dry weights compared to the control. All treatments increased Ca and Mg concentrations compared to the control, with the highest Mg concentration observed under HK + Ca + Mg treatment and the highest Ca concentration is found with HK + Ca + Mg and Ca + Mg treatments. The highest N concentrations were observed in cocopeat with HK treatments and in soil with HK + Ca + Mg, compared to the control. The Ca concentration was higher under B + FR and R + FR, and Mg concentration was highest under R and R + B. HK, Ca + Mg, and HK + Ca + Mg treatments consistently improved the nutritional status of lettuce plants, making HK a promising organic amendment for enhancing plant growth and nutrient uptake in both soil and soilless cultivation systems.
The morphology of sheep wool applied as organic fertilizer biodegraded in the soil was examined. The investigations were conducted in natural conditions for unwashed waste wool, which was rejected during sorting and then chopped into short segments and wool pellets. Different types of wool were mixed with soil and buried in experimental plots. The wool samples were periodically taken and analyzed for one year using Scanning Electron Microscopy (SEM) and Energy-dispersive X-ray Spectroscopy (EDS). During examinations, the changes in the fibers’ morphology were observed. It was stated that cut wool and pellet are mechanically damaged, which significantly accelerates wool biodegradation and quickly destroys the whole fiber structure. On the contrary, for undamaged fibers biodegradation occurs slowly, layer by layer, in a predictable sequence. This finding has practical implications for the use of wool as an organic fertilizer, suggesting that the method of preparation can influence its biodegradation rate.
Despite the increase in digital products and practices, humans are still sociomaterially tangled with material-based design and tangible artefacts in their everyday lives. From the designer's perspective, recent research shows that materials significantly affect the design processes, ideation, tools, and use areas. From the human/user perspective, research shows that experiences and interactions with tangible outcomes affect behaviours, expectations, thinking, and cognitive development. On the other hand, from the environmental perspective, new material development has been a crucial topic in managing production, consumption, regeneration, environmental impact, and self-sufficiency. Thus, materials convey performative roles in realities that design creates or relates to. With changing knowledge and sensitivities, revisiting traditional practices and craft materials can deliver insights to tackle material interaction from cultural and systemic perspectives. In socio-material entanglements, multiple elements, systems, and histories come together across time and space, shaping ever-changing understandings of material's role in design, use, and nature. In the continuous becoming of humans, interacting with materials plays a significant role. By looking into human-material entanglements in the design scope, this paper aims to bring an expansive approach to studying the reciprocal creation of natural and human-made systems. To discuss the layers and multitudes of systems that design practice is part of, the paper follows the material journey of a felted artefact as an example. Felting 2 is an art, craft, design, and industry practice that typically relies on entangling wool fibres to create a compound surface. Through an ethnographic study of interactions embedded in the potential lifecycle of a felted artefact, this paper sheds light on various actors, relations, and systems that different stages of design practice entangle. Having the examination on a small-scale studio practice provides a concrete explanation of how even seemingly simplistic practices embody deeply intricate relationships. Following the vital materials perspective, the paper elucidates a material journey map of a felted artefact divided into five stages of becoming: matter, material, design, use, and afterlife. By following the becoming of material, the paper exposes underlying aspects and intricacies of systems and underscores the importance of comprehending these interwoven situations. In this way, the paper identifies key points to consider when studying different relations and proposes a lens to study direct and indirect interactions embedded in design practice. The developed material journey map can also be proposed as a tool to be employed by designers when studying use areas and the potential impact of emerging materials. The current state of the world dictates reviewing the most common consumption/ production behaviours and mindsets to maintain a living earth. Parts of the problem are landfills of items made of all sorts of materials and exploitation of nature for material generation. New materials have been developed for biodegradable and sustainable solutions to minimise the destructive impact. These endeavours emerge through research and development projects as well as designer-led small-scale experiments to explore potential raw materials, develop recycling methods for new and existing materials, and manage waste and material innovations require an PROCEEDINGS OF RELATING SYSTEMS THINKING AND DESIGN, RSD12 3 understanding of materials, technologies, and production methods (Kääriäinen & Niinimäki, 2019). Understanding materials also facilitates understanding humans as we constantly interact with materials in the form of artefacts, raw materials, or matter found in the natural environment. These interactions with the outside world shape how humans think in the extended world with their minds and bodies (Johnson 2007). Therefore, studying material interaction can provide insights into human thinking and sustainably co-exist with the world. This paper examines a material's journey, namely wool, as an example to scrutinise different settings where human-material interaction takes place. It aims to present the entangled situations that materials are part of to bring attention to the materials not only in specific and independent phases, such as recycling or generation, but from an interdependent perspective to see their relations to various systems. The paper proposes material journey mapping as a tool for studying its relations in various material contexts.
In recent years, many alternative bio‐waste‐based fertilizers have been proven to have a beneficial effect on plant nutrition. These also include wool pellet, whose comprehensive evaluation of synergistic effects on plant development and soil biological activity is still a limited field of investigation. To address this, we explored the potential of combining soil inoculations and N‐rich wool pellet as ecologically sound alternatives to N fertilizers. In a pot experiment, we investigated the effect of Azotobacter vinelandii, the Trichoderma harzianum T34, and wool pellet, individually and in combination, on the growth and nitrate uptake of the test plants, as well as on the biological activity and permanganate‐oxidizable carbon of the sandy soil with low organic matter content. The combination of T. harzianum + wool pellet showed the highest biological activity and permanganate‐oxidizable carbon content, while the untreated control plants exhibited the lowest values. The treatment combination of wool pellet and A. vinelandii exhibited the highest nitrate uptake by plants. Measuring the concentration of photosynthetic pigments, net photosynthesis, transpiration rate, stomatal conductance, and total dry biomass, we found that the treatments led to a significant improvement in the photosynthetic intensity of lettuce plants. These results suggest that wool pellet served as a significant source of N and that their biological activity plays a key role in improving plant parameters. Moreover, the combination of microbial inoculants and wool pellet effectively increases N use efficiency in plant growth.
Coarse wool obtained from mountain sheep has low economic value and is treated as a troublesome by-product of sheep farming. To find ways to utilize it, waste separated from the better-quality wool during sheep shearing was used as a fertilizer in winter wheat cultivation. During the preliminary tests, it was stated that unwashed wool does not contain excessive amounts of heavy metals and environmentally unfriendly contaminations and can be safely used as a fertilizer. Then, the raw wool was cut into shorter segments and mixed with the soil, and its influence on winter wheat growth during two seasons was examined. Simultaneously, the progress of wool biodegradation and the nitrogen content in the soil were analyzed. It was stated that, during vegetation, nitrogen compounds are slowly released into the ground, and the content of nitrogen in the soil is strictly correlated with the progress of wool biodegradation. Released nitrogen positively impacts wheat growth in various stages, which is manifested by higher tillering degree, more intense leaf color, higher stems and finally, greater yield. Wool added into the soil reveals its positive influence on wheat development up to two harvests. Mountain sheep wool can be successfully used as a nitrogen-rich, organic fertilizer in organic farming. This enables utilization of coarse wool, which is not suitable for textile processing, according to the zero-waste strategy.
Peptones are one of the most expensive components of microbial culture media. The present study was conducted to test the usability of low-cost sheep wool peptone (SWP) as an organic nitrogen source in the production of six industrially important enzymes (lipase, amylase, tannase, pectinase, cellulase and invertase). SWP was prepared by alkaline hydrolysis and acid neutralization. Bacillus licheniformis and Aspergillus niger were selected as test microorganisms for enzyme production. To evaluate the efficacy of SWP in enzyme production, it was compared with commercial tryptone peptone (TP) in the shaking flask cultures of the test microorganisms. The optimum concentration of both SWP and TP was determined to be 8 g/L for the production of B. licheniformis-derived enzymes, but 6 g/L for the production of A. niger-derived enzymes. It was determined that SWP was superior to TP in the production of four enzymes (lipase, amylase, tannase and pectinase) of both B. licheniformis and A. niger. This is the first study about the usage of sheep wool protein hydrolysate (SWP) as an organic nitrogen source or a peptone in fermentative production of microbial enzymes.
The problem of soil salinity is rapidly increasing, with more than 950 million hectares affected by salinity stress (Arora et al., 2017). The amelioration of saline-sodic soils using chemical ameliorates could increase CO2 emissions and soil degradation. Therefore, amending saline-sodic soil with environmentally friendly bio-organic ameliorants such as brewer's spent grain (SG) and Azospirillum (A. brasilense) bacteria could represent a safe and cheaper approach compared to other organic (compost; CT) and mineral fertilizers. Under greenhouse conditions, maize was grown in saline-sodic soil amended with bio-organic ameliorants. Nine treatments were included; (i) SG1 (23.8 t ha-1); (ii) SG2 (47.6 t ha-1); (iii) TC1 (23.8 t ha-1) ; (iv) TC2 (47.6 t ha-1); (v) injection of A. brasilense with corn seeds (Az); (vi) combination of A. brasilense and SG (Az+SG1); (vii) combination of A. brasilense and compost (Az+TC1); (viii) mineral fertilizers (NPK) and (ix) the control (CK). The results revealed that soil amended with Az and SG2 significantly decreased the exchangeable sodium percentage (ESP) and higher cation exchange capacity (CEC). Compared with the control, the exchangeable sodium (Ex-Na +) concentration was decreased by 53.2 and 49.27%, for Az and Az+SG1 treatments, respectively. The fresh-and dry weight observed for Az+SG1, SG2, and Az treatments were increased compared to TC1, TC2, NPK, and CK treatments. The grain and biological yields were higher 2 in Az+SG1 and SG2 than in TC2, NPK ameliorants, and CK. The bio-organic ameliorants alleviated the abiotic stress, enhance the growth and productivity of corn plants, decrease soil ESP and Na + content, and enhance soil fertility. In conclusion, the application of SG2 can enhance the growth, and productivity of maize grown under salinity-sodicity stress. Therefore, SG2 and Az+SG1 are recommended for direct application in saline-sodic soil.
In recent years the use of organic matter soil amendments, such as agricultural by-products, has been implemented with the aim of increasing soil fertility, while minimizing the environmental impact of agriculture. Sheep wool residues (SWR) have shown beneficial effects on plant nutrition and soil properties, while only few works assessed their impact on soil microbial communities. The main aim of this work was to investigate the possible valorization of two SWR types (scoured residues, white wool, WW, and carbonized scoured residues, black wool, BW) as organic soil amendments, in pot-grown olive trees, by evaluating their impact on soil bacterial communities and mycorrhizal symbionts. The two SWR types did not negatively impact on the diversity and composition of soil bacterial communities, as revealed by PCR-denaturating gradient gel electrophoresis (PCR-DGGE) of partial 16S rRNA gene, and on the activity of native arbuscular mycorrhizal fungi (AMF), while positively affecting plant growth. Only the highest doses of one SWR type (2% BW) caused a decrease in bacterial diversity and native AMF ability to colonize olive roots. DGGE bands sequencing allowed the identification of the major bacterial taxa. Sequences corresponding to Ohtaekwangia spp., Beta proteobacterium, Blastocatella sp., Ramlibacter monticola and Massilia frigida/rubra , Dongia sp. and Chloroflexi were mainly represented in SWR-amended soils, while those represented by Chryseolinea soli and Acidobacteria were abundant in control soil. Overall, this work showed that SWR may be valorized as organic soil amendments, as soil bacteria and AMF, representing key factors of biological soil fertility, were not negatively affected, while the activity of bacterial genera and species known for their ability to decompose complex compounds was boosted. Further studies will investigate the biodegradation efficiency of the diverse bacterial taxa developing in SWR-amended soils.
Graphic Abstract
The Silesian Beskids (Poland), the westernmost part of the Carpathian Mountains is an area with long pastoral tradition. For centuries sheep grazed in clearings located among forested ridges have been an integral part of the mountain landscape and pastoral customs have become essential elements of regional cultural heritage. In the chapter, the history and the current state of pastoralism in the Silesian Beskids are presented. The specific pastoral system developed in the region, based on annual migration of flocks between summer highland and winter lowland pastures is described. Local breeds and specific regional sheep products are depicted. Furthermore, the importance of pastoralism for the environment, landscape and plant biodiversity is analysed and efforts to recover sheep grazing in the mountains after a period of a deep recession caused by social and economic transitions connected with the collapse of the communist system are presented. The approach to restoration of pastoralism is illustrated using a case study of a pastoral centre which combines traditional sheep grazing with cheese production, education and several activities to promote pastoral tradition.
Raw sheep wool contains various impurities such as wax, suint, dirt, and microorganisms. Water-based cleaning process of sheep wool requires toxic volatile organic compounds that generate a significant portion of toxic effluents. Supercritical CO 2 (scCO 2) is a waterless technology that has been utilized for sterilization, extraction, cleaning, and drying in various manufacturing sectors. The application of the scCO 2 technology in sheep wool processing is cleaner, as it avoids the generation of toxic effluents. scCO 2 is a promising technology that can be simultaneously utilized in sheep wool processing for sterilization, extraction of lanolin, and cleaning and drying. Therefore, the present study was conducted to evaluate the potential and limitations of the use of the scCO 2 technology for sheep wool processing. Moreover, the properties of sheep wool, the impurities associated with sheep wool fiber, and treatment technology are discussed.
Purpose
Climate change and global food demand in coming decades urge effective actions for more efficient uses of water and soil resources. This paper reports the preliminary findings of a study assessing the potential of sheep scoured wool residues (SWRs) as soil amendments to enhance the physical and hydraulic properties of a sandy loam soil under rain conditions.
Methods
Two different SWRs were used: scoured residues (white wool, WW) and carbonized scoured residues (black wool, BW) at different SWRs/soil ratios (0.0, 0.5, 1.0 and 2.0%). Soil bulk density (BD), total porosity (TP), aggregates stability, aggregate size distribution, saturated hydraulic conductivity, and water retention properties were determined under rain conditions, in addition to rainwater balance (storage, percolation and runoff).
Results
Both WW and BW, particularly at the high wool/soil ratio (2%), significantly reduced soil BD by 11.98% and 9.85%, respectively. Moreover, WW and BW increased TP by 16.45% and 13.57% and available water capacity by 6.5% and 18.1%, respectively. SWRs increased the formation of macro-aggregates and increased aggregate stability. The results of rainwater balance showed higher percolation percentages and less rainwater storage in the wool-treated soil.
Conclusions
The increase in water percolation is in line with the increased total porosity and the higher saturated hydraulic conductivity of wool-treated soil. Despite the high capacity of absorbing water, SWRs affected the water movement of the soil more than its water retention.
Soil amendment using organic fertilizer has been used widely to dispose animal waste, reduce environmental pollution and improve soil and fruit quality. The objective of this two-year study was to assess the influence of organic and conventional systems on growth, marketable yield, head quality (chlorogenic acid and cynarin concentration) and soil chemical properties of globe artichoke (Cynara cardunculus). Cultivars used were Deserto, Lulu, Romolo, 11-018, 12-179, Green Globe Improved and Imperial Star. Fertilizers were applied to both conventional and organic soil through drip irrigation system. In both years, significant differences were found across cultivars and soil type. Although cultivar response to soil system treatments were inconsistent across the two growing seasons, the cv. Imperial Star had the lowest marketable yield and head quality. Artichoke grown in the conventional field had higher plant height and width, chlorophyll content index (SPAD), leaf area index (LAI), stomatal conductance (gs), photosynthesis (Pn) and marketable yield. Conversely, artichoke head quality from the organic field was higher than conventional. Organic system increased chlorogenic acid by 31% and cynarin by 12% compared to the conventional system. In fact, after two years of soil amendment, organic fertilizer improved soil respiration-CO2 (soil health indicator) by 20-fold compared to chemical fertilizer (conventional field). Overall, based on this two-year study we suggest organic farming as the best system to improve soil and head quality of globe artichoke, but it may not be the best option for farmers when yield is the primary target short-term.
The application of different organic matter sources as soil amendments is a common practice to stimulate root development and soil quality to improve crop yield and quality. For evaluating the effect of organic amendments on soil quality indicators and agronomic variables in table grape (Vitis vitifera) var Thompson seedless, different treatments including compost from grape pomace, humic extract, microbial inoculant, and chemical NPK fertilization, were evaluated in a pot experiment using an Inceptisol soil. Organic materials were applied in four C rates: compost, 0, 125, 250 y 500 g C pot-1; humic extract, 0, 25, 50 and 100 g C pot-1; compost and humic extract at their maximum C rates were also evaluated in absence of chemical fertilization, and microbial inoculant as bio-stimulant. Results showed a stronger root development in plants with compost and inoculant application. Furthermore, organic matter mineralization increased nutrient availability; this was evidenced by an increment of enzymatic activities, particularly β-glucosidase, acid phosphatase, and alkaline phosphatase, in all treatments receiving compost. On the other hand, the application of humic extract produced a larger increment in WSC per carbon unit applied compared to compost, meaning that the former would be more efficient than the latter to provide C for soil microorganisms. This study showed that the joint application of compost, mineral fertilizer, and microbial inoculant should be considered to improve root development in Table grape (Vitis vinifera L.) and soil quality, under Integrated Nutrient Management (INM) programs.
Organic and inorganic nutrients are important for crop productivity and soil health. Present study investigated the effects of organic and inorganic manures on maize and their residual impacts on soil physico-chemical characteristics. Sheep manure (SM), poultry manure (PM) and farmyard manure (FYM) were applied as organic nutrient source while urea, diammonium phosphate (DAP) and sulphate of potash (SOP) were used at different concentrations as inorganic nutrients source viz., T1: Unfertilized control; T2: NPK at 250-150-125 kg ha-1; T3: SM at 15 t ha-1; T4: FYM at 16 t ha-1; T5: PM at 13 t ha-1; T6: NPK at 150-85-50 + 8 t ha-1 SM; T7: NPK at 150-85-50 + 8.5 t ha-1 FYM and T8: NPK at 150-85-50 + 7 t ha-1 PM. Results showed that growth and yield of maize were substantially improved by fertilizer application alongside organic manures whereas soil total organic C and total N, P, K contents increased when inorganic fertilizers were applied alone or in combined with organic manures. However, soil pH and soil bulk density decreased due to application of organic fertilizer and showed a negative correlation with grain yield. Further, a significant and positive correlation (R²= 0.52, 0.91 and 0.55) was observed among maize grain yield and available N, P and K contents, respectively in the soil. Conclusively, integration of inorganic fertilizers with organic manures can be used with optimum rates to improve crop productivity on sustainable basis. This study will be helpful in crafting sustainable nutrient management programs in future to enhance crop productivity with high efficiency and minimum nutrient loss.
This edition updates a narrative that has been at the forefront of soil science for more than a century. The first edition, published in 1909, was largely a guide to good soil management for farmers in the glaciated regions of New York State in the northeastern U.S. Since then, it has evolved to provide a globally relevant framework for an integrated understanding of the diversity of soils, the soil system and its role in the ecology of planet Earth.
The 15th edition is the first to feature full-color illustrations and photographs throughout. These new and refined full color figures and illustrations help make the study of soils more efficient, engaging, and intellectually satisfying. Every chapter has been thoroughly updated with the latest advances, concepts, and applications. Hundreds of new key references have been added. The 15th edition, like preceding editions, has greatly benefited from innumerable suggestions, ideas, and corrections contributed by soil scientists, instructors, and students from around the world. Dr. Nyle Brady, although long in retirement and recently deceased, remains as co-author in recognition of the fact that his vision, wisdom and inspiration continue to permeate the entire book.
This edition,1082 pages in length, includes in-depth discussions on such topics of cutting edge soil science as the pedosphere concept, new insights into humus and soil carbon accumulation, subaqueous soils, soil effects on human health, principles and practice of organic farming, urban and human engineered soils, cycling and plant use of silicon, inner- and outer-sphere complexes, radioactive soil contamination, new understandings of the nitrogen cycle, cation saturation and ratios, acid sulfate soils, water-saving irrigation techniques, hydraulic redistribution, cover crop effects on soil health, soil food-web ecology, disease suppressive soils, soil microbial genomics, indicators of soil quality, soil ecosystem services, biochar, soil interactions with global climate change, digital soil maps, and many others. In response to their popularity in recent editions, I have also added many new boxes that present either fascinating examples and applications or technical details and calculations. These boxes both highlight material of special interest and allow the logical thread of the regular text to flow smoothly without digression or interruption.
For students: This book provides both an exciting, accessible introduction to the world of soils as well as a reliable, comprehensive reference that you will want to keep for your professional bookshelf. What you learn from its pages will be of enormous practical value in equipping you to meet the many natural-resource challenges of the 21st century. The book demonstrates how the soil system provides many opportunities to see practical applications for principles from such sciences as biology, chemistry, physics, and geology. Throughout, the text highlights the countless interactions between soils and other components of forest, range, agricultural, wetland, and constructed ecosystems.
As the global economy expands exponentially societies face new challenges with managing their natural resources. Soil as a fundamental natural resource is critical to sustained economic growth and the prosperity of people in all parts of the world. To achieve balanced growth with a sustainable economy while improving environmental quality, it will be necessary to have a deep understanding of soils, including their properties, functions, ecological roles and management. I have tried to write this textbook in a way designed to engage inquisitive minds and challenge them to understand soils and actively do their part as environmental and agricultural scientists, in the interest of ensuring a prosperous and healthy future for humanity on planet Earth. It is my sincere hope that this book, previous editions of which have served so many generations of soil students and scientists, will continue to help future generations of soil scientists to benefit from a global ecological view of soils.
The increase in world population has posed more pressure in existing arable lands. The nutrients poor sandy soils could be productive if their content of organic matter can be increased. Agricultural and animal wastes instead of being dumped, could offer a cheap alternative source of organic matter to increase soil fertility. Three glasshouse short-term experiments were carried out to evaluate the effects of incorporation of: (1) agricultural residues (trashes of Cajanus cajan and sugarcane factory by- product (baggase); (2) recycling of various vegetable market wastes and; (3) application of animal wastes (hoof and wool) on soil properties and performance of fodder sorghum (Sorghum bicolor L.) or maize (Zea mays L.). Results showed that almost all sources of organic materials had resulted in significant positive effects on accumulation of plant dry matter and soil physical and chemical characteristics. Organic amendments are necessary for the sustainable use of nutrient-poor Sudanese sandy soils.
The use of organic and completely compostable substrates is of rising interest in hydroponics. In Germany unclean sheepwool is available as waste material. The objective of this experiment was to investigate the development and yield of cucumber grown on sheepwool slabs in comparison with peat slabs, coconut fibre slabs, perlite and rockwool slabs. The experiment was conducted in a soilless culture system with trickle irrigation. The nutrient solution was recirculated separately for each substrate variant. Additionally, 50% of the cucumber plants of each substrate were treated three times with a complex biostimulator. This biostimulator consists of humic acid, lactic acid and Bacillus subtilis and was applied to the rhizosphere. The structure of all substrates was analysed before and after use. The air capacity of sheepwool before use was much higher (70%) than of the other substrates (18–58%) but decreased with use to 43%. The water capacity of sheepwool was about 23% before use and increased up to 44% after use. The bulk density of sheepwool ranged between 70 and 80 g L-1 and was significantly lower than that of the other substrates after use. On sheepwool the highest yield was recorded. In all variants with biostimulator treatment the yield was higher than without treatment. Sheepwool can be recommended as substrate for cucumber growing.
Plant water use efficiency (WUE) is becoming a key issue in semiarid areas, where crop production relies on the use of large volumes of water. Improving WUE is necessary for securing environmental sustainability of food production in these areas. Given that climate change predictions include increases in temperature and drought in semiarid regions, improving crop WUE is mandatory for global food production. WUE is commonly measured at the leaf level, because portable equipment for measuring leaf gas exchange rates facilitates the simultaneous measurement of photosynthesis and transpiration. However, when those measurements are compared with daily integrals or whole-plant estimates of WUE, the two sometimes do not agree. Scaling up from single-leaf to whole-plant WUE was tested in grapevines in different experiments by comparison of daily integrals of instantaneous water use efficiency [ratio between CO2 assimilation (AN) and transpiration (E); AN/E] with midday AN/E measurements, showing a low correlation, being worse with increasing water stress. We sought to evaluate the importance of spatial and temporal variation in carbon and water balances at the leaf and plant levels. The leaf position (governing average light interception) in the canopy showed a marked effect on instantaneous and daily integrals of leaf WUE. Night transpiration and respiration rates were also evaluated, as well as respiration contributions to total carbon balance. Two main components were identified as filling the gap between leaf and whole plant WUE: the large effect of leaf position on daily carbon gain and water loss and the large flux of carbon losses by dark respiration. These results show that WUE evaluation among genotypes or treatments needs to be revised.
The book begins with a detailed description of the characteristics of the photosynthetic apparatus and the processes that take place there, to then present the general principles of fluorescence. After that, it gives a description of the characteristics of direct and modulated fluorescence and a presentation of the shared and distinctive parameters of these two techniques. Then a brief presentation is made of other innovative approaches to the analysis of fluorescence (Chlorophyll Fluorescence Imaging - CFI, P700 absorbance, delayed fluorescence) and the relative tools. An important part of the book comprises a description of the possible applications of fluorescence techniques for the analysis of various types of stress (aridity, strong light radiations, UV, high and low temperatures, salinity, weedkillers, pollution, etc.) and, consequently, their possible use in agriculture, forestry and to protect the environment.
Suitable conditions were found for hydrolysis of sheep wool by a mixture of potassium hydroxide and some quantities of sodium hydroxide at elevated temperature (120° C) and pressure (2.03 atm). Because of the severe hydrolysis conditions (pH about 12 and high temperature) it is believed that the causes of some related diseases like “mad cow”, “swine fever”, bovine spongiform encephalopaty, Creutzfeldt-Jakob disease, that are called prions, and are proteins will be destroyed. The hydrolysate obtained is neutralized by orto-phosphoric acid. Beside organic nitrogen, the obtained hydrolysate contains also potassium and phosphate ions and threfore it is proposed this product to be used as fertilizer in the agriculture. Data are supplied showing the positive effect on rye-grass when the soil was additionally enriched with the new fertilizer. The alkaline hydrolysate contains about 75–80 water-soluble materials—peptides, amino acids, salts, dyes, lipids and some carbohydrates. The remaining part consists of insoluble partly degraded keratin. The latter is highly dispersed and therefore it is believed that it will be degraded by the soil microorganisms for relatively short time, thus feeding the plants additionally.
Sheep's wool and leather shavings tanned without chromium (III) salts would be suitable for fertilization in organic farming, where is the lack of easily accessible fertilizer nitrogen. This hypothesis was tested in a two-year field experiment growing asparagus at Rogelj organic farm in Kranj (Slovenia). The block designed experiment with three replicates comprised fertilization treatments with sheep's wool (W), leather shavings (L), cattle manure (FYM) and unfertilized (Ø). Doses of fertilizers were relevant to 0 (Ø), 140 (W1, L1), 280 (W2, L2, FYM) and 560 kg (W3, L3) N/ha. Fertilizers were dosed the first year before the start of the vegetation. Within the next year we followed their subsequent effect. The highest soil mineral N was found in the W2, which produced also the highest asparagus yield (nonsignificant) in the first year. On contrary, NO3-N content in the asparagus crop was small what reflects the good synchrony of N mineralization and consumption of N at W2. Treatments W and L released significantly more N in the next year than the same dose of nitrogen from FYM. The experiment showed that mainly sheep wool represents a quality alternative organic fertilizer.
Biofortification—with either the application of zinc and iron fertilizer or the application of amendments to increase their bioavailability in soil—is a possible strategy to tackle worldwide micronutrient malnutrition. We investigated the effect of hydrolysed wool on the uptake of zinc and iron by wheat (Triticum aestivum var. Greina). We performed pot experiments in which either hydrolysed wool or mineral fertilizer of the same elemental composition was incorporated into a loamy-sand collected from an agricultural field. Zinc grain concentrations were 37.7 mg kg−1 (control), 45.5 mg kg−1 (mineral fertilization) and 54.1 mg kg−1 (hydrolysed wool). In addition, hydrolysed wool application increased grain yield 2-fold and grain protein content 1.5-fold, compared with 1.4-fold and 1.3-fold, respectively, by the mineral fertilizer. We propose that hydrolysed wool could be used to supplement other fertilizers, enhancing the latter with an easily available N source as well as promoting zinc and iron uptake in plants.
The hypothesis of this work was that uncomposted sheep wool and human hair could be used as nutrient source for nonedible high-value plants. Pot and field experiments were conducted to assess uncomposted sheep wool-wastes and human hair-wastes as a nutrient source for high-value crops and to evaluate the effect of these waste materials on soil microbial community and mycorrhizae. In the pot experiments, addition of uncomposted wool- or hair-waste to soil increased yields from pot marigold (Calendula officinalis L.) and valerian (Valeriana officinalis L.). In the field experiment, wool-waste was added to purple foxglove (Digitalis purpurea L.) at rates of 0, 15.8, and 31.7 t ha(-1). Wool additions to soil increased foxglove yields over the next two seasons by 1.7 to 3.5 times relative to the control. Overall, addition of wool- or hair-waste to soil increased NH(4)-N and NO(3)-N in soil, increased total N (and protein) concentration in plant tissue, and stimulated soil microbial biomass. Scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) analyses indicated that some of wool and hair in soil from the pot and field experiments, after two seasons and several harvests, retained their original structure, a significant concentration of S, some N, and were not fully decomposed. High rates of wool addition to soil in field experiments resulted in shifts in the microbial community composition, while a low rate of wool-waste addition did not affect the microbial community relative to the unamended control. Our results suggest that the addition of uncomposted wool-waste or hair-waste of only 0.33% by weight to soil would support at least 2 to 3 harvests of crops, without the addition of other fertilizers. Uncomposted wool and hair-wastes can be used as a nutrient source for high-value crops.
In the UK, 400 million tonnes of waste are generated each year. A considerable amount of this waste is attributed to construction and demolition wastes that are destined for landfill sites. Textiles, including carpet waste, on the other hand, account for only 2% of all wastes by weight but because of their high volume-to-weight ratio, once dumped into landfills they occupy large spaces. Besides, given the high added values of carpets, carpet waste account for almost £70 million of lost revenue per year in the UK. Increasing public concern for the environment and higher taxations imposed on landfill dumping are forcing manufacturers of various disciplines to seriously reduce their waste and/or find new applications for their inevitable waste. This article reports on one such application where carpet fibrous waste is included in clayey or substandard soils with the intention of enhancing soil cohesion and reinforcement. The findings suggest that inclusion of as much as 10% fibers can be tolerated and would enhance internal cohesion, shear and comprehensive strength as well as load-bearing capacity of this kind of soils. Soil moisture content is also reported to play an important role in enhancing cohesion and compressive strength of such combinations.
In this experiment, the influences of three different organic sources on some physical and chemical fertility properties in soil were investigated. The approach involved establishing a plot experiment in the greenhouse with a Lithic Rhodoxeralf and a variety of carbon sources having specific chemical properties applied to the soil of individual plots. Treatments include potassium (K)–humate (KH, 25, 50 and 100 kg ha−1), concentrated plant extract (CPE, 50, 100 200 kg ha−1), and molasses (M, 50, 100 200 kg ha−1). After a 7-month incubation period, soil organic matter (SOM), total nitrogen (N), soil reaction (pH), electrical conductivity (EC), cation exchange capacity (CEC), base saturation (BS), and bulk density (BD) were determined, and their correlation to different C sources was developed. With respect to the unamended soil, soil treated with intermediate and high doses of all organic amendments showed apparent increases of SOM, total N, pH, EC, and CEC and a slight decrease of BD.
This chapter deals with chlorophyll (Chi) a fluorescence signals and describes how fluorescence transients, known commonly as Kautsky curves, exhibited by photosynthetic
organisms under different conditions can be analyzed to provide detailed information about the structure, conformation and
function of the photosynthetic apparatus and especially of photosystem (PS) II. The emphasis in this chapter is on the work
done by R. J. Strasser and his co-workers. The analytical formulation of the biophysics of the photosynthetic apparatus, according
to models of different complexity regarding both the architecture of the photosynthetic unit and the modes of energetic communication
among the pigment assemblies, as well as their links to the experimental fluorescence signals are derived, based on the so-called
‘Theory of Energy Fluxes in Biomembranes’. In this framework, the derivation of simple mathematical formulae expressing the
energetic communication among PS II units, called in the literature as ‘grouping’ or ‘connectivity’, is presented in detail
and the ‘overall grouping probability,’ which takes into account all possible pathways of communication, is defined. The chapter
starts with fluorescence transients exhibited (a) in the presence of DCMU (3 -(3,4-dichlorophenyl)-1,1 -dimethylurea) at room
temperature and (b) at low temperature (77K), i.e. under conditions that reduce the complexity of the in vivo system, and
then focuses on the analysis of the polyphasic fluorescence transient under physiological conditions, with emphasis on the
fluorescence rise kinetics O-J-I-P (labeled also in the literature as 0-IrI2-P). The analysis of strong actinic light-induced
O-J-I-P transients by, what we call, the ‘JlP-test’, which can be applied at any physiological state and for the study of
any state transition, is presented in detail; it includes the full derivation of the formulae for the constellation of experimentally
accessible parameters. These include the so-called ‘specific’ and ‘phenomenological’ energy fluxes, the yields, the fraction
of PS II reactions centers (RCs) that can not reduce the primary quinone acceptor of PS II, QA, called as heat sinks or ‘silent’ centers, the fraction of RCs that can not reduce the secondary PS II quinone acceptor QB, as well as the overall grouping probability. The influence of the donor side of PS II on the fluorescence kinetics, with
emphasis on the appearance under certain conditions of an early step (at about 300 μs, labeled as the K-step) in the regular
O-J-I-P fluorescence transient, related to the inactivation of the water splitting system, is also discussed. Moreover, results
from numerical simulations of the O-J-I-P transient are summarized with emphasis on the investigation of the possible role
of the PS II primary acceptor pheophytin. The chapter closes with the presentation of recent advances, achieved by simultaneous
in vivo measurements of Chi a fluorescence rise kinetics and P700 oxidation kinetics.
1. Plant growth is a fundamental ecological process, integrating across scales from physiology to com- munity dynamics and ecosystem properties. Recent improvements in plant growth modeling have al- lowed deeper understanding and more accurate predictions for a wide range of ecological issues, includ- ing competition among plants, plant-herbivore interactions and ecosystem functioning.
2. One challenge in modeling plant growth is that, for a variety of reasons, relative growth rate (RGR) almost universally decreases with increasing size, though traditional calculations assume that RGR is constant. Nonlinear growth models are flexible enough to account for varying growth rates.
3. We demonstrate a variety of nonlinear models that are appropriate for modeling plant growth and, for each, show how to calculate function-derived growth rates, which allow unbiased comparisons among species at a common time or size. We show how to propagate uncertainty in estimated parameters to ex- press uncertainty in growth rates. Fitting nonlinear models can be challenging, so we present extensive worked examples and practical recommendations, all implemented in R.
4. The use of nonlinear models coupled with function-derived growth rates can facilitate the testing of novel hypotheses in population and community ecology. For example, the use of such techniques has allowed better understanding of the components of RGR, the costs of rapid growth, and the linkage be- tween host and parasite growth rates. We hope this contribution will demystify nonlinear modeling and persuade more ecologists to use these techniques.
The pressure chamber has been widely used in the measurement of total water potential and pressure-volume relations of leaves, twigs and, to a lesser extent, roots. Some of the benefits and precautions in its use in these studies are reviewed and discussed. The pressure chamber has also been used to determine hydraulic resistances of plants, to collect xylem sap, to determine the water potential at various points in the xylem and to establish membrane damage of plants. Developments in this field are reviewed and discussed.
Photosynthetic efficiency of two Syrian barley landraces Arabi Aswad and Arabi Abiad grown under different light intensities were studied by the application of qualitative and quantitative analysis of chlorophyll a fluorescence. Different values of fluorescence parameters, quantum efficiencies, specific and phenomenological energy fluxes were obtained for each cultivar. Both low and high light stresses decreased photosystem II (PSII) activity in barley seedlings depending on the stress type and its duration. Cultivar Arabi Aswad was more tolerant to high light while Arabi Abiad was more tolerant to low light stress. The results allowed us to select chlorophyll a fluorescence parameters related to energy flux within PSII which were specifically affected under low or high light stress. We found that the performance index parameter is a sensitive indicator to explore the effect of light changes on PSII activity immediately after stress application, while maximal quantum yield of PSII and phenomenological parameters were only modified after a long period of stress application indicating PSII damage. Thus, we recommend the former parameter for early detection of light stress.
Disposal of post-consumer carpets produces large volumes of waste for landfills where they do not readily degrade. Incineration is only possible in countries with the necessary infrastructure and increasing environmental pressure makes incineration unsustainable.We have shown that wool carpets can be used as a fertiliser with excellent results. Ground-up wool carpet, when added to the soil, greatly increases the yield (wet and dry matter) of grass grown. This closed-loop cycle (i.e., grass-wool-carpet-grass) is an efficient form of fibre recycling because the carpet to grass step is solar powered, unlike recycling of synthetic fibres.The suitability of ground-up wool carpets as fertiliser is confirmed by elevated levels of essential elements such as nitrogen (19%), sulphur (19%) and magnesium (7%) in the grass grown on carpet fertilised plots as compared to the control grass. The environmental soundness of wool carpet has been supported by the results of this simple experiment.
Thalli of the foliose lichen species Parmelina tiliacea were studied to determine responses of the photosynthetic apparatus to high temperatures in the dry and wet state. The speed with which dry thalli were activated by water following a 24 h exposure at different temperatures decreased as the temperature was increased. But even following a 24 h exposure to 50 °C the fluorescence induction kinetics OJIP reflecting the reduction kinetics of the photosynthetic electron transport chain had completely recovered within 128 min. Exposure of dry thalli to 50 °C for 24 h did not induce a K-peak in the fluorescence rise suggesting that the oxygen evolving complex had remained intact. This contrasted strongly with wet thalli were submergence for 40 s in water of 45 °C inactivated most of the photosystem II reaction centres. In wet thalli, following the destruction of the Mn-cluster, the donation rate to photosystem II by alternative donors (e.g. ascorbate) was lower than in higher plants. This is associated with the near absence of a secondary rise peak (~1 s) normally observed in higher plants. Analysing the 820 nm and prompt fluorescence transients suggested that the M-peak (occurs around 2-5 s) in heat-treated wet lichen thalli is related to cyclic electron transport around photosystem I. Normally, heat stress in lichen thalli leads to desiccation and as consequence lichens may lack the heat-stress-tolerance-increasing mechanisms observed in higher plants. Wet lichen thalli may, therefore, represent an attractive reference system for the evaluation of processes related with heat stress in higher plants.
Globally, we are applying excessive nitrogen (N) fertilizers to our agricultural crops, which ultimately causes nitrogen pollution to our ecosphere. The atmosphere is polluted by N₂O and NO(x) gases that directly and indirectly increase atmospheric warming and climate change. Nitrogen is also leached from agricultural lands as the water-soluble form NO₃⁻, which increases nutrient overload in rivers, lakes, and oceans, causing "dead zones", reducing property values and the diversity of aquatic life, and damaging our drinking water and aquatic-associated industries such as fishing and tourism. Why do some countries show reductions in fertilizer use while others show increasing use? What N fertilizer application reductions could occur, without compromising crop yields? And what are the economic and environmental benefits of using directed nutrient management strategies?
Drought stress has multiple effects on the photosynthetic system. Here, we show that a decrease of the relative contribution of the I-P phase, DeltaV(IP) = -V(I) = (F(M)-F(I))/(F(M)- F(o)), to the fluorescence transient OJIP is observed in 10 drought-stressed barley and 9 chickpea varieties. The extent of the I-P loss in the barley varieties depended on their drought tolerance. The relative loss of the I-P phase seems to be related to a loss of photosystem (PS) I reaction centers as determined by 820-nm transmission measurements. In the second part of this study, the interaction of drought and heat stress in two barley varieties (the drought tolerant variety Aït Baha and the drought sensitive variety Lannaceur) was studied using a new approach. Heat stress was induced by exposing the plant leaves to temperatures of 25-45 degrees C and the inactivation of the O(2)-evolving complex (OEC) was followed measuring chlorophyll a (Chl a) fluorescence using a protocol consisting of two 5-ms pulses spaced 2.3 ms apart. In active reaction centers, the dark interval is long enough to allow the OEC to recover from the first pulse; whereas in heat-inactivated reaction centers it is not. In the latter category of reaction centers, no further fluorescence rise is induced by the second pulse. Lannaceur, under well-watered conditions, was more heat tolerant than Aït Baha. However, this difference was lost following drought stress. Drought stress considerably increased the thermostability of PS II of both varieties.
A field and two container experiments were conducted to assess uncomposted wool and hair wastes as a nutrient source for crops and to evaluate their potential to improve soil biological and chemical properties. Overall, addition of wool or hair waste to soil increased yields of basil (Ocimum basilicum L. 'Trakia'), thorn apple (Datura innoxia Mill. 'Inka'), peppermint (Mentha x piperita L. 'Black Mitchum'), and garden sage (Salvia officinalis L. 'Desislava'), increased NH(4)-N and NO(3)-N in soil, increased total N (and protein) content in plant tissue, stimulated soil microbial biomass, and decreased mycorrhizae colonization of plant roots of thorn apple but not in basil. Wool and hair waste additions to soil altered slightly the content and composition of plant secondary metabolites (essential oils or alkaloids); however, overall the constituents remained within the "typical" range for the respective crops. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis demonstrated that wool and hair wastes decompose slowly under field or greenhouse conditions, and act as a slow release S, N, P, and K fertilizer. These results, along with the measured concentrations of NO(3)-N in soil at harvest, suggest that the addition of wool or hair waste of only 3.3 g kg(-1) of soil may support two to five harvests or crops under greenhouse conditions and two to four field seasons in field production systems, and would improve soil biological and chemical characteristics. Further research is needed to optimize the rate of application of these waste materials to the nutrient requirements of specific crops to avoid nitrate leaching into the ground water. In addition, the effect of wool and hair waste on other environmental end points should also be further investigated before specific recommendations for growers are provided.
Because of expanding markets for high‐value niche crops, opportunities have increased for the production of medicinal herbs in the USA. An experiment was conducted in 2001 and 2002 near Gilbert, IA, to study crop performance, weed suppression, and environmental conditions associated with the use of several organic mulches in the production of two herbs, catnip ( Nepeta cataria L.) and St. John's wort ( Hypericum perforatum L. ‘Helos’). Treatments were arranged in a completely randomized design and included a positive (hand‐weeded) control, a negative (nonweeded) control, oat straw, a flax straw mat, and a nonwoven wool mat. Catnip plant height was significantly greater in the oat straw than the other treatments at 4 wk through 6 wk in 2001; at 4 to 8 wk in 2002, catnip plant height and width was significantly lower in the negative control compared with the other treatments. Catnip yield was significantly higher in the flax straw mat than all other treatments in 2001. In 2002, St. John's wort yields were not statistically different in any treatments. All weed management treatments had significantly fewer weeds than the non‐weeded rows in 2002. Total weed density comparisons in each crop from 2 yr showed fewer weeds present in the flax straw and wool mat treatments compared with positive control plots. There was no significant weed management treatment effect on the concentration of the target compounds, nepetalactone in catnip and pseudohypericin–hypericin in St. John's wort, although there was a trend toward higher concentrations in the flax straw treatment.
The effect of C/N ratio on decomposition after amendment with individual litters and their mixes has been studied extensively. But less is known about the effect of highly decomposed organic materials such as manures on interactions in mixes. In this study, a sandy clay loam was amended with finely ground young faba bean shoots (FB, C/N 9), sheep manure (SM, C/N 6) and mature wheat straw (W, C/N 82) either individually (referred to as 100FB, 100SM, 100SM) or as mixes (e.g. 75FB-25SM, 50FB-50SM, 25FB-75SM, where the value represents the weight percentage of the organic materials). Soil was sampled on days 16, 32 and 48. Cumulative respiration after 48 days was similar with 100FB and 100 W, where it was about seven-fold higher than in 100SM. It decreased with percentage SM in the mixes and was about two-fold higher in 25SM-75 W than in 75SM-25 W. Available N was low with 100 W and microbial biomass N (MBN) was low with 100SM (five-fold lower than with FB). In mixes of W with FB or SM, available N was between two and 40-fold lower than expected with greater differences between measured and expected values FB-W than with SM-W. In FB-W and SM-W mixes, MBN was between 50% and two-fold higher than expected. In mixes of FB and SM, MBN on day 16 was 50% higher than expected in 75FB-25SM, but 30–50% lower than expected in mixes with ≥50% SM. We conclude that mixing of W with FB can provide plants with N, but also reduce N loss via leaching or denitrification.
Chlorophyll fluorescence analysis has become one of the most powerful and widely used techniques available to plant physiologists and ecophysiologists. This review aims to provide an introduction for the novice into the methodology and applications of chlorophyll fluorescence. After a brief introduction into the theoretical background of the technique, the methodology and some of the technical pitfalls that can be encountered are explained. A selection of examples is then used to illustrate the types of information that fluorescence can provide.
A large amount of coarse wool, practically unserviceable for textile uses, is generated in Europe from sheep shearing and butchery. Such a by-product that is either dumped, burned or sent to landfill. Following the European Commission regulations on animal by-product control, unserviceable raw wool is classified as category 3 special waste materials. The collection, storage, transport, treatment, use and disposal of such unserviceable raw wool are subjected to European Union regulations because of a potential risk source to human and animal health. This study aims at converting the waste wool into nitrogen fertilizers at a commercial scale for grassland management and cultivation purposes. The chemical transformation of waste wool in to fertilizer is based on a green economically sustainable hydrolysis treatment using superheated water. The experiments were carried out in a semi-industrial reactor feeding superheated water. The wool/superheated water system was maintained for different reaction times. The optimal conditions for this treatment were: 170 oC for 60 min with a solid to liquor ratio (MLR) close to 1. The hydrolyzed product was analyzed using amino acid analysis and molecular weight distribution. Both the amino acid and molecular weight distribution analysis revealed that the wool was completely degraded and the hydrolyzed product contains a low molecular weight proteins and amino acids. Several hydrolyzed product obtained at different conditions were tested for germination which showed a germination index higher than 100% without collateral phytotoxicity. The presence of amino acids, primary nutrients and micronutrients in wool hydrolyzates, along with a concentration of heavy metals below the standard limit, confirms the possibility of using wool hydrolyzates as nitrogen based ecologically sound fertilizer.
Sheep wool can be a waste products of sheep husbandry. Its safe utilization evokes several serious problems. Therefore, it was of interest to check out the usefulness of wool as a fertilizer and/or substrate. The aim of the experiments reported in this paper was to evaluate the effect of the washed sheep wool used as an amendment to peat-based growing substrate on growth and yield of tomato, sweet pepper, and eggplant. The layer of wool was spread on 5 cm thick strata of substrate and covered with the same substrate at a rate of 10 g wool per 1 dm3 of substrate. Plants were grown individually in containers. It was stated that the addition of wool caused up to 33% higher yields, especially for tomato and pepper. Wool amendment caused changes in nutrients content of substrate and leaves. Thus, sheep wool can serve as a valuable and environmentally friendly fertilizer.
To meet the requirement of ever increasing population, modern agricultural practices rely heavily on artificial or chemical fertilizers, which later on creates critical pollution problems. To avoid the use of these chemical fertilizers, number of waste material and by products (such as animal manure, municipal solid waste compost and sewage sludge) are used currently in agricultural crop production. An attempt is made in this work by the use of uncomposted hair waste as nutrient source for high value plants and to evaluate the effect of these waste materials on soil microbial community. In the Pot experiment, the addition of uncomposted hair waste to soil increased yield in Spinach. Addition of hair waste also increased NH4-N and NO3-N in soil, increased total N concentration in plant tissue and stimulated soil microbial biomass. It's addition also increased conc. of N, S, Ca, Na, Fe, Cu, Zn and Mn in soil as well as in plant tissue. Our result suggest that the addition of 13.33 g/Kg or 29866.66 Kg/ha of hair is sufficient for Spinach crop and can support at least 2-3 harvest of crops, without the addition of other fertilizers.
Management of waste wool is a problem related to sheep farming and butchery in Europe. Since the primary role of European flock is meat production, sheep are crossbreds not graded for fine wool production. Their wool is very coarse and contains a lot of kemps (dead fibres), so that it is practically unserviceable for textile uses, and represents a by-product which is mostly disposed off. Green hydrolysis using superheated water is an emerging technology to turn waste wool into amendment-fertilizers for the management of grasslands and other cultivation purposes. In this way wool keratin (the wool protein) is degraded into simpler compounds, tailoring the release speed of nutrients to plants. Wool, when added to the soil, increases the yield of grass grown, absorbs and retains moisture very effectively and reduces run off of contaminants such as pesticides. Moreover, the closed-loop cycle grass–wool–grass is an efficient form of recycling, because the wool-grass step is solar powered and grazing sheep increases soil carbon sequestration on grasslands and fertilisation, if not over-used, can enhance the carbon sequestration rate. Economical results of using hydrolysed wool as a fertilizer are expected from the increase of the management yield and the extension of the pasture lands that may contribute to employment and profit of sheep farming, increase European sheep population, and reduce European dependency of imported meat which is forecast to rise in the next years.
Municipal waste management in the UK has undergone rapid transformation in recent years in pursuit of greater sustainability. In this paper we explore the environmental justice issues and tensions involved in this shift. After a brief overview of environmental justice debates and how they have been related to issues of waste management, we describe how the policies and processes underlying the transformation from an overwhelming dependence on landfill disposal towards more sustainable methods of management has been driven by European legislation embodying principles premised on fundamental environmental concerns of inter- and intra-generational equity. We analyse the key means through which these principles have been translated to restructure local authority practices and the environmental justice issues arising from the implementation of international policy in regional and local context. Finally, we reflect on the implications of this case study for implementation of policies intended to advance both sustainability and environmental justice.
Laboratory compaction and triaxial compression tests were performed to assess the compaction characteristics and load deformation response of a sandy silt reinforced with randomly oriented recycled carpet fibers. Discrete, randomly distributed fiber inclusions significantly increase the peak shear strength, reduce the postpeak strength loss, increase the axial strain to failure, and, in some cases, change the stress-strain behavior from strain softening to strain hardening for a sandy silt. Fiber inclusions also impede the compaction process, causing a reduction in the maximum dry density of reinforced specimens with increasing fiber content. The strength losses associated with in-service saturation are significantly reduced with fiber reinforcement. It is suggested that large volumes of recycled waste fibers can be used as a value-added product to enhance the shear strength and load deformation response of soils.
A soil column method was used to compare the effect of drip fertigation (the application of fertilizer through drip irrigation systems, DFI) on the leaching loss and transformation of urea-N in soil with that of surface fertilization combined with flood irrigation (SFI), and to study the leaching loss and transformation of three kinds of nitrogen fertilizers (nitrate fertilizer, ammonium fertilizer, and urea fertilizer) in two contrasting soils after the fertigation. In comparison to SFI, DFI decreased leaching loss of urea-N from the soil and increased the mineral N (NH4+-N + NO3−N) in the soil. The N leached from a clay loam soil ranged from 5.7% to 9.6% of the total N added as fertilizer, whereas for a sandy loam soil they ranged between 16.2% and 30.4%. Leaching losses of mineral N were higher when nitrate fertilizer was used compared to urea or arrmonium fertilizer. Compared to the control (without urea addition), on the first day when soils were fertigated with urea, there were increases in NH4+-N in the soils. This confirmed the rapid hydrolysis of urea in soil during fertigation. NH4+-N in soils reached a peak about 5 days after fertigation, and due to nitrification it began to decrease at day 10. After applying NH4+-N fertilizer and urea and during the incubation period, the mineral nitrogen in the soil decreased. This may be related to the occurrence of NH4+-N fixation or volatilization in the soil during the fertigation process.
a b s t r a c t Proteins represent the dominant input of organic N into most ecosystems and they also constitute the largest store of N in soil organic matter. The extracellular protease mediated breakdown of proteins to amino acids therefore represents a key step regulating N cycling in soil. In this study we investigated the influence of a range of environmental factors on the rate of protein mineralization in a grazed grassland and fallow agricultural soil. The protein turnover rates were directly compared to the rates of amino acid mineralization under the same conditions. Uniformly 14 C-labelled soluble protein and amino acids were added to soil and the rate of 14 CO 2 evolution determined over 30 d. Our results indicate that the primary phase of protein mineralization was approximately 20 AE 3 fold slower that the rate of amino acid mineralization. The addition of large amounts of inorganic NO 3 À and NH 4 þ to the soil did not repress the rate of protein mineralization suggesting that available N does not directly affect protease activity in the short term. Whilst protein mineralization was strongly temperature sensitive, the presence of plants and the addition of humic and tannic acids had relatively little influence on the rate of soluble protein degradation in this fertile grassland soil. Our results suggests that the extracellular protease mediated cleavage of proteins to amino acids rather than breakdown of amino acids to NH 4 þ represents the limiting step in soil N cycling.
Potato leaf discs were infiltrated in darkness with a buffer of pH 5 containing 100 M ascorbate, resulting in a massive conversion of the carotenoid violaxanthin to zeaxanthin. In vivo measurements of modulated chlorophyll a fluorescence indicated that this treatment (1) caused a marked upward shift of the threshold temperature at which photosystem II denatures and (2) noticeably inhibited the rate of dark reoxidation of the reduced plastoquinone (at low temperature). These changes were not induced in leaves infiltrated with a buffer of pH 5 containing no ascorbate or with 100 mM ascorbate at pH >7.2. The above-mentioned effects were also observed during heat acclimation (34°C for several days) of potato plants and suggested that zeaxanthin interacts with the lipid phase of the thylakoid membranes. Based on those results and the previous data obtained with model systems, it is suggested that the xanthophyll cycle could be a regulatory mechanism adjusting thylakoid membrane fluidity, the significance of which for the photoprotection of the photosynthetic apparatus is discussed.
The effect of adding alkaline hydrolysate of sheep’s wool waste on the chemical and microbiological properties of a park soil
(Sofia, Bulgaria) has been assessed in a 9month laboratory experiment. The waste product contained 75–80% water-soluble materials:
peptides, amino acids, salts, dyes, lipids, some carbohydrates, potassium ions, and it seemed likely that the hydrolysate
obtained could be used as a harmless and valuable fertilizer in agriculture. It was demonstrated that the organic material
positively influenced microbial soil populations and ryegrass growth. As the remaining partially degraded keratin is highly
dispersed it should act as a slow release fertilizer thus feeding plants additionally. The results suggest that the wool hydrolysate
is beneficial for improving soil characteristics and could successfully be used as alternative biofertilizer. The authors
hope that by utilization of the keratin wastes, the environment around leather and fur plants could be influenced positively
and that the expense of removing the wastes to controlled landfill sites and part of the expenses for sustaining the latter
will be saved.
In this study the influences of three different organic sources on aggregate formation and stability in soil were investigated.Our approach involves establishing plot experiment in the greenhouse with a Lithic Rhodoxeralf and a variety of carbon sources having specific chemical properties applied to the soil of individual plots. Treatments include K-Humate (KH, 25, 50 and 100 kg/ha), Concentrated Plant Extract (CPE, 50, 100, 200 kg/ha) and Molasses (M, 50, 100, 200 kg/ha). After a seven-month incubation period, aggregate formation and their stability were determined and their correlation to different C sources was developed.The effect of KH on aggregate formation was significant for 2–1 mm aggregates (P < 0.05) and 0.5–0.25 mm aggregates (P < 0.01). The effect of CPE on aggregate formation was significant for 0.5–0.25 aggregates (P < 0.05), while the M had no significant effect on aggregate formation in any aggregate size. The effect of KH on aggregate stability was significant for 8–4 mm and 1–0.5 mm aggregates (P < 0.01). The effect of CPE on aggregate stability was significant for 0.5–0.25 mm aggregates (P < 0.05), while the M was significant for 8–4 mm aggregates (P < 0.05).
The observations of a long-term experiment on the use of saline water were used to compare the crop tolerance to salinity. Salinity affected significantly yield, evapotranspiration, pre-dawn leaf water potential and stomatal conductance. The higher the salinity, the lower the yield, evapotranspiration, pre-dawn leaf water potential and stomatal resistance. The crop classification, based on soil salinity, corresponds with the classification of Maas and Hoffman: sugarbeet and durum wheat as salt tolerant, broadbean, maize, potato, sunflower and tomato as moderately salt sensitive. The difference with respect to soybean, classified as moderately salt sensitive instead of moderately salt tolerant can be ascribed to difference in variety. Weather conditions affected strongly the salt tolerance of broadbean. The water stress day index was also used for salt tolerance classification. According to this method, maize, sunflower and potato were included in the same salt tolerant group as sugarbeet and durum wheat. The previous classification of maize and sunflower as moderately sensitive is caused by the fact that these crops are grown during a period of higher evaporative demand than when sugarbeet and durum wheat are grown. The change of potato from moderately sensitive to salt tolerant may be ascribed to its shallow root system.
The effect of air and water temperature upon the decomposition of human remains and upon biological activity has been extensively studied. However, less attention has been devoted to the temperature of the soil surrounding burials, despite its potential influence upon chemical reactions involved in the decomposition of human remains, drugs and toxins, as well as upon microbial and insect activity. A soil temperature calculation equation usually employed in civil engineering was used to calculate soil temperature at various depths in a cemetery located in Brisbane, Australia, in order to explain the extensive degradation of human remains and funerary objects observed at exhumation. The results showed that for the 160 years of the site's history, ground temperature at burial level had been sufficiently high for biological activity and chemical degradation reactions to continue right up until the time of exhumation. The equation used has potential in the analysis of both cemetery and clandestine burials, since it allows ground temperature to be calculated from ambient air temperature figures, for a variety of depths, soil types and vegetation conditions.
Organic farming systems often comprise crops and livestock, recycle farmyard manure for fertilization, and preventive or biocontrol measures are used for plant protection. We determined indicators for soil quality changes in the DOK long-term comparison trial that was initiated in 1978. This replicated field trial comprises organic and integrated (conventional) farming systems that are typical for Swiss agriculture. Livestock based bio-organic (BIOORG), bio-dynamic (BIODYN) and integrated farming systems (CONFYM) were compared at reduced and normal fertilization intensity (0.7 and 1.4 livestock units, LU) in a 7 year crop rotation. A stockless integrated system is fertilized with mineral fertilizers exclusively (CONMIN) and one control treatment remained unfertilized (NOFERT). The CONFYM system is amended with stacked manure, supplemental mineral fertilizers, as well as chemical pesticides. Manure of the BIOORG system is slightly rotted and in BIODYN it is composted aerobically with some herbal additives. In the third crop rotation period at normal fertiliser intensity soil organic carbon (Corg, w/w) in the plough layer (0–20 cm) of the BIODYN system remained constant and decreased by 7% in CONFYM and 9% in BIOORG as compared to the starting values. With no manure application Corg-loss was severest in NOFERT (22%), followed by CONMIN together with the systems at reduced fertiliser intensity (14–16%). Soil pH tended to increase in the organic systems, whereas the integrated systems had the lowest pH values. At the end of the third crop rotation period in 1998 biological soil quality indicators were determined. Compared to soil microbial biomass in the BIODYN systems the CONFYM soils showed 25% lower values and the systems without manure application were lower by 34%. Relative to the BIODYN soils at the same fertilization intensity dehydrogenase activity was 39–42% lower in CONFYM soils and even 62% lower in soils of CONMIN. Soil basal respiration did not differ between farming systems at the same intensity, but when related to microbial biomass (qCO2) it was 20% higher in CONFYM soils and 52% higher in CONMIN as compared to BIODYN, suggesting a higher maintenance requirement of microbial biomass in soils of the integrated systems. The manure based farming systems of the DOK trial are likely to favour an active and fertile soil. Both, Corg and biological soil quality indicators were clearly depending on the quantity and quality of the applied manure types, but soil microbial biomass and activities were much more affected than Corg.
A container experiment was conducted to test the hypothesis that uncomposted wool wastes could be used as nutrient source and growth medium constituent for container-grown plants. The treatments were: (1) rate of wool-waste application (0 or unamended control, 20, 40, 80, and 120 g of wool per 8-in. pot), (2) growth medium constituents [(2.1) wool plus perlite, (2.2) wool plus peat, and (2.3) wool plus peat plus perlite], and (3) plant species (basil and Swiss chard). A single addition of 20, 40, 80, or 120 g of wool-waste to Swiss chard (Beta vulgaris L.) and basil (Ocimum basilicum L.) in pots with growth medium provided four harvests of Swiss chard and five harvests of basil. Total basil yield from the five harvests was 1.6-5 times greater than the total yield from the unamended control, while total Swiss chard yield from the four harvests was 2-5 times greater relative to the respective unamended control. The addition of wool-waste to the growth medium increased Swiss chard and basil tissue N, and NO(3)-N and NH(4)-N in growth medium relative to the unamended control. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) microanalysis of wool fibers sampled at the end of the experiments indicated various levels of decomposition, with some fibers retaining their original surface structure. Furthermore, most of the wool fibers' surfaces contained significant concentrations of S and much less N, P, or K. SEM/EDX revealed that some plant roots grow directly on wool-waste fibers suggesting either (1) root directional growth towards sites with greater nutrient concentration and/or (2) a possible role for roots or root exudates in wool decomposition. Results from this study suggest that uncomposted wool wastes can be used as soil amendment, growth medium constituent, and nutrient source for container-grown plants.
The keratinase production by the thermophilic actinomycete strain Thermoactinomyces candidus was induced by sheep wool as the sole source of carbon and nitrogen in the cultivation medium. For complete digestion of wool by the above strain, both keratinolytic serine proteinase and cellular reduction of disulfide bonds were involved. Evidence was presented that substrate induction was a major regulatory mechanism and the keratinase biosynthesis was not completely repressed by addition of other carbon (glucose) and nitrogen (NH4C1) sources. The enzyme was purified 62-fold by diethylaminoethyl-anion exchange and Sephadex G-75 gel permeation chromatographies. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the purified keratinase is a monomeric enzyme with a molecular mass of 30 kDa. The pH and temperature optima were determined to be 8.6 and 70 degrees C, respectively. The purified thermophilic keratinase catalyses the hydrolysis of a broad range of substrates and displays higher proteolytic activity against native keratins than other proteinases. Ca2+ was found to have a stabilizing effect on the enzyme activity at elevated temperatures.
Chlorophyll fluorescence analysis has become one of the most powerful and widely used techniques available to plant physiologists
and ecophysiologists. This review aims to provide an introduction for the novice into the methodology and applications of
chlorophyll fluorescence. After a brief introduction into the theoretical background of the technique, the methodology and
some of the technical pitfalls that can be encountered are explained. A selection of examples is then used to illustrate the
types of information that fluorescence can provide.
Visible ozone symptoms on leaves are expressions of physiological mechanisms to cope with oxidative stresses. Often, the symptoms consist of stippling, which corresponds to localized cell death (hypersensitive response, HR), separated from healthy cells by a layer of callose. The HR strategy tends to protect the healthy cells and in most cases the efficiency of chlorophyll to trap energy is not affected. In other cases, the efficiency of leaves to produce biomass declines and the plant loses its photosynthetic apparatus replacing it with a new, more efficient one. Another strategy consists of the production of pigments (anthocyanins), and leaves become reddish. In these cases, the most significant physiological manifestation consists of the enhanced dissipation of energy. These different behavior patterns are reflected in the initial events of photosynthetic activity, and can be monitored with techniques based on the direct fluorescence of chlorophyll a in photosystem II, applying the JIP-test.
Phytoextraction has revealed great potential, however it is limited by the fact that plants need time and nutrient supply and have a limited metal uptake capacity. Although the use of synthetic chelators, such as EDTA, enhances heavy metal extraction, it also produces the negative side effects of high phytotoxicity, as well as leaching of essential metals. The aim of this research was to investigate the application of wool, in mobilising metals and in improving the phytoextraction of metals-contaminated soil. We performed column experiments with 14 d and 7 d partially hydrolysed wool as chelating agent on a silty-loamy sand agricultural soil. In the column experiment the 14 d wool hydrolysate mobilised 68% of Cu in soil, whereas in the case of Cd it mobilised 5.5%. The model plant selected for the phytoextraction experiments was tobacco (Nicotiana tabacum). The plant uptake of Cd and Cu, assisted by the application of 6.6 g kg(-1) wool hydrolysate was increased by 30% in comparison to the control plants. The application of 13.3 g kg(-1) wool hydrolysate enhanced the Cu uptake by up to 850%. Moreover, high leaching probability frequently observed when applying chelating agents, such as EDTA or ethylene diamine disuccinate (EDDS), were not detected. The use of hydrolysed wool therefore merits further investigation.
Halophytes, plants that survive to reproduce in environments where the salt concentration is around 200 mm NaCl or more, constitute about 1% of the world's flora. Some halophytes show optimal growth in saline conditions; others grow optimally in the absence of salt. However, the tolerance of all halophytes to salinity relies on controlled uptake and compartmentalization of Na+, K+ and Cl- and the synthesis of organic 'compatible' solutes, even where salt glands are operative. Although there is evidence that different species may utilize different transporters in their accumulation of Na+, in general little is known of the proteins and regulatory networks involved. Consequently, it is not yet possible to assign molecular mechanisms to apparent differences in rates of Na+ and Cl- uptake, in root-to-shoot transport (xylem loading and retrieval), or in net selectivity for K+ over Na+. At the cellular level, H+-ATPases in the plasma membrane and tonoplast, as well as the tonoplast H+-PPiase, provide the trans-membrane proton motive force used by various secondary transporters. The widespread occurrence, taxonomically, of halophytes and the general paucity of information on the molecular regulation of tolerance mechanisms persuade us that research should be concentrated on a number of 'model' species that are representative of the various mechanisms that might be involved in tolerance.
Soil screening guidance: technical background document. Office of Solid Waste and Emergency Response
- S Epa
S. EPA (1996) Soil screening guidance: technical background document. Office of Solid Waste and Emergency Response. U.S.
Environmental Protection Agency. Publication 9355.4-17A,
Washington, DC