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The Nature and Properties of Soil
Abstract and Figures
Thoroughly updated and now in full color, the 15th edition of this market leading text brings the exciting field of soils to life. Explore this new edition to find:
A comprehensive approach to soils with a focus on six major ecological roles of soil including growth of plants, climate change, recycling function, biodiversity, water, and soil properties and behavior.
New full-color illustrations and the use of color throughout the text highlights the new and refined figures and illustrations to help make the study of soils more efficient, engaging, and relevant.
Updated with the latest advances, concepts, and applications including hundreds of key references.
New coverage of cutting edge soil science. Examples include coverage of 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, new understandings of the nitrogen cycle, water-saving irrigation techniques, hydraulic redistribution, soil food-web ecology, disease suppressive soils, soil microbial genomics, soil interactions with global climate change, digital soil maps, and many others
Applications boxes and case study vignettes bring important soils topics to life. Examples include “Subaqueous Soils—Underwater Pedogenesis,” “Practical Applications of Unsaturated Water Flow in Contrasting Layers,” “Soil Microbiology in the Molecular Age,” and "Where have All the Humics Gone?”
Calculations and practical numerical problems boxes help students explore and understand detailed calculations and practical numerical problems. Examples include “Calculating Lime Needs Based on pH Buffering,” “Leaching Requirement for Saline Soils,” "Toward a Global Soil Information System,” “Calculation of Nitrogen Mineralization,” and “Calculation of Percent Pore Space in Soils.”
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... The observed exchangeable P increase in soils treated with sole fertilizer and fertilizer + manure can be attributed to the immediate supply of P from applied mineral fertilizers. According to Lal and Stewart [37], Muindi et al. [38], Muindi et al. [39], Muindi [40], Weil and Brady [41] phosphorus is an immobile element that can persist in soils if not lost through crop uptake, runoff, adsorption by clay colloid, oxides and hydroxides of Fe and Aluminium in acidic soils and carbonates and bicarbonates of calcium and magnesium in saline soils. Continuous decomposition and mineralization of organic matter can also avail more mineral Phosphorus in soil solution or buffer soil pH promoting Phosphorus release from colloidal structures [40][41][42]. ...
... According to Lal and Stewart [37], Muindi et al. [38], Muindi et al. [39], Muindi [40], Weil and Brady [41] phosphorus is an immobile element that can persist in soils if not lost through crop uptake, runoff, adsorption by clay colloid, oxides and hydroxides of Fe and Aluminium in acidic soils and carbonates and bicarbonates of calcium and magnesium in saline soils. Continuous decomposition and mineralization of organic matter can also avail more mineral Phosphorus in soil solution or buffer soil pH promoting Phosphorus release from colloidal structures [40][41][42]. Additionally, the organic matter presence can avail more P in soil solution by reducing P chelation by lowering the activities of the polyvalent cations such as Ca, Al and Fe that form insoluble salts with P [43,44]. ...
... Values followed by the same letter(s) on the same column are not significantly different at P ≤ 0.05 The observed plant height increase in manure and fertilizer treated in both maize and green grams after inorganic fertilizer application might be plants compared to unfertilized plants can also be attributed to availability of soil solution nitrogen and phosphorus for uptake from applied fertilizers. While Nitrogen plays crucial role in vegetative growth, phosphorus is key in germination and root formation [40,41] promoting new cells development, plant vigour, leaves and height. This finding concur with Aslam et al. [50] who reported increased plant height and number of green gram branches on application of inorganic fertilizers and Rewe et al. [51] who reported increased maize height and number of leaves on combined application of slurry and inorganic fertilizer. ...
Mining is an important economic activity globally that is associated with provision of raw materials, industrial growth, employment creation as well as degradation of natural ecosystems and agricultural land. A study was conducted at Base Titanium limited mining company to evaluate the response of maize-green intercrop to farmyard manure and mineral fertilizer in post mined soils. Treatments were sole manure, sole inorganic fertilizer, manure + inorganic fertilizer and unfertilized (control) laid down in randomised complete block design (RCBD) and replicated three times. Data Original Research Article Kiponda et al.; J. 35 collected included soil nutrients before and after cropping, maize and green grams growth and yield parameters. Obtained data was subjected to analysis of variance using genstat software and means separated using Fisher's LSD. The post mined soils were slightly acidic with optimal levels of Ca, Mg, Mn and Zn, Low levels of P,K, S, B,Cu, CEC, TN and organic matter. After two cropping seasons, S and TN was observed to increase in all treatments, while Ca, Mg, Mn, B and Zn decreased in all treatments. Combined manure and fertilizer application increased average maize plant height, stem circumference and LAI by 38%, 34%, 60% respectively and ears per plant, cob length, grains per cob, grain yield and dry matter weight by 57%, 13%, 47%, 31% and 35% respectively compared to unfertilized plants. Green grams growth and yield in the intercropping system was however not significant after either manure and/or fertilizer application. Although the findings showed that manures and fertilizers application improved nutrient availability in this post mined soils, further research is required to ascertain maize-green gram intercrop, optimal establishment time, spacing, fertilizer and manure rates that can provide optimal intercrop yield as well as soil regeneration.
... Besides being a rich source of protein, green gram roots are important sources of soil nitrogen. The roots have the ability to develop nodules that help in fixing atmospheric nitrogen in the soil through nitro-bacter bacteria through biological nitrogen fixation process [18,19]. According to 18, the crop has the ability to add about 30-40kg N/ha in a single season. ...
... Most green gram cultivation areas are located in arid and semi-arid areas which are designated to be sensitive to climate variability and highly vulnerable to unpredictable rains, frequent droughts during cropping seasons or occasional severe floods [49,50,51]. Owing to the fact that optimal crop growth and yield require provision of all nutrients in rightful forms and amounts, water plays major role as a solvent that eventually determine germination, nutrient uptake, metabolisms, assimilation, photosynthesis and other plant biochemical processes [19]. Most green gram production areas within the country have been experiencing erratic rains and frequent drought over the past years, leading to up to 79% decrease in production in some seasons [53,54]. ...
... The land degradation forms of importance in green gram production ecosystems include: soil erosion, deterioration of soil physical, chemical, biological or economic properties and, long-term loss of natural vegetation and biota among others [65]. According to [19], adequate availability of nutrients in rightful proportions is paramount in crop growth and productivity. The seventeen nutrients required by plants include: carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), chlorine (Cl), boron (Bo) and molybdenum (Mo) [19,68]. ...
Green gram (Vigna radiata L. Wilczek), also known as mung bean, is an important grain legume containing a high amount of digestible protein, amino acids, sugar, minerals, soluble dietary fibers, and vitamins. In Kenya, green gram production is done mainly by smallholder farmers for food and sale. The crop is mainly grown in arid and semi-arid regions and plays important role towards achieving improved human nutrition and health conditions, reducing poverty through food security and enhancing ecosystem resilience as a source of human food, animal feed, soil nitrogen and soil health. Statistics show that though average area under production has been growing since 1978, average production has been fluctuating and consumption increasing steadily upholding constant deficit which is catered for through imports. The country's average green gram yield ranges between 0.5-0.6 ton/ha compared to crop potential of 1.5 ton/ha and global average yield of 0.73 Review Article Muchomba et al.; J. 2 tons/ha. The production is mainly constrained by myriad of factors such as climate change effects, pest and disease prevalence, poor agronomic practices, land degradation and soil health decline. Other challenges included: lack of structured marketing systems and poor research-extension-farmer linkages, Possession of limiting climate smart agriculture knowledge and skills. Access to credit facilities and agro processing technologies as well as narrow post-harvest loss management knowledge and skills was also identified as other key green gram production constraints more so for small scale farmers. It was however noted that the country has potential to achieve optimal greengram production and optimal production require adoption of climate smart technologies, improved flow of information, streamlined government policies, credit facilities as well as structured market system. The current work reviews green gram crop, with emphasis on its biology, economic importance, ecological requirements, current production status in Kenya, production constraints and their management.
... The permeability class for the investigated soil is rapid (6 -20 inch.hr -1 ) according to Brady et al. (2008), where its value is 6.25m.day -1 . ...
... Cation exchange capacity is a soil chemical parameter aimed at assessing changes in soil quality following the application of different agro-techniques and rarely investigated in studies, despite it providing useful information about potentially available cations for plant nutrition and, indirectly, holding water capacity [13]. Cation exchange capacity mainly depends on soil texture, and on the quantity and humification degree of soil organic matter [42]. Considering that soil texture did not change among treatments during the field trials (data not shown), it can be inferred that the high CEC in mulched soils, especially in those mulched for 15 years, was due to the concomitant increase in TOC. ...
Weed control in urban and peri-urban orange orchards is challenging due to operational and legislative restrictions. Tillage, besides from negatively affecting soil fertility and microorganisms, is demanding for humans. On the other hand, herbicides are advised against due to the possibility to reach waterbodies from the soil surface. Therefore, in urban and peri-urban areas, instead of tillage and herbicides, mulching with black plastic geotextile fabric is often used. This study aimed at assessing the impact of long-term soil mulching with black plastic geotextile fabric on soil fertility, microbial community and yield of an orange orchard in comparison to conventional tillage. To this aim, four soil management systems were set up: rotary tillage for the last 15 years, mulching with black plastic geotextiles for the last 15 years, rotary tillage for 7 years followed by mulching for the last 8 years, mulching for 7 years followed by rotary tillage for the last 8 years. Soil samples were analyzed to determine the chemical and biochemical parameters related to soil fertility. In addition, the abundances of the main microbial groups were investigated. Mulching increased soil total organic C at least by 65%. The greater soil organic C in mulched soil in turn contributed to increase the cation exchange capacity (+62% on average) and microbial biomass C (+120% on average). Additionally, the microbial quotient exhibited higher values in mulched soils compared to tilled ones, suggesting a greater soil organic matter accessibility by soil microorganisms. Moreover, mulching favored fungi over bacteria, and Gram-positive bacteria over Gram-negative bacteria, thus contributing to the establishment of a microbial community more efficient in utilizing C sources. The latter result was confirmed by the lower values of the metabolic quotient in mulched soil compared to tilled one. Overall, the black plastic geotextile fabric improved chemical and biochemical soil fertility that, in turn, lead to a higher orange yield in mulched soil.
... Therefore, evaluation of the straw decomposition pattern and the associated microbial communities involved in the decomposition under the different rates of N fertilizer application, gives an insights into the scientific management of crop residues apart from enhancing the nutrient uptake (Guo et al. 2018). Due to microbial decomposition crop residue converted into different easily mineralizable form of the soil organic matter (Brady and Weil 2005). Plants directly and indirectly take up the mineralized form of plant nutrients from the soil solution. ...
A field experiment was conducted during rainy (kharif) and winter (rabi) seasons 2019-20 and 2020-21 at the research farm of ICAR-Indian Agricultural Research Institute, New Delhi to study the effect of rice establishment techniques (RETs) and microbial consortia mediated in situ rice residue management options on nitrogen (N) budgeting in a rice (Oryza sativa L.)-wheat (Triticum aestivum L.) cropping system (RWCS). The experiment was laid out in split plot design with 3 replications having 2 main plot treatments, viz. aerobic rice (AR) and conventional transplanted rice (CTR) in kharif and 7 sub plot treatments, viz. clean cultivation (removal of paddy straw), paddy straw incorporation, paddy straw mulching, paddy straw incorporation + Pusa decomposer, paddy straw mulching + Pusa decomposer, paddy straw incorporation + urea @20 kg/ha, paddy straw incorporation + Pusa decomposer + urea @10 kg/ha. The residual effects of these treatments were observed in seed drill and zero till sown wheat in rabi seasons. Results showed that N uptake (95.1 kg/ha and 100.4 kg/ha in CTR and 79.4 kg/ha and 83.8 kg/ha in AR) was significantly superior in CTR than AR in kharif seasons. The residual effects of in situ rice residue management options in wheat, paddy straw incorporation + Pusa decomposer + urea @10 kg/ha resulted in significantly higher N uptake (136.4 and 141.5 kg/ha) than other treatments, and it was followed by paddy straw incorporation + Pusa decomposer in both the years. The nutrient uptake by the RWCS was an important indicator of soil fertility and plant nutrient status. This investigation concluded that there is need for use of microbial consortia mediated in situ rice residue management in RWCS for positive N balance in spite of enhanced nutrient uptake.
... Before walnut plantations reaches economic maturity, the intercrop -winter cereals (Triticum spp), alfafa (Medicago sativa), soybean (Glycine max), or summer crops (e.g., maize) -is the only income during the first five to ten years; thereafter both trees and intercrops produce simultaneously (Mary 1998). Among these AM-dependent intercrops, maize (Zea mays L.), is one of the most cultivated crops for both staple food and industrial usage, in tropical and temperate soils worldwide, with phosphorus being a major growth limiting factor for commercial maize production (Brady and Weil 2008). ...
Under agroforestry practices, inter-specific facilitation between tree rows and cultivated alleys occurs when plants increase the growth of their neighbours especially under nutrient limitation. Due to a coarse roots architecture limiting soil inorganic phosphate (Pi) uptake, walnut trees (Juglans spp.) exhibit dependency on soil-borne symbiotic arbuscular mycorrhizal fungi that extend extra-radical hyphae beyond the root Pi depletion zone. To investigate the benefits of mycorrhizal walnuts in alley cropping, we experimentally simulated an agroforestry system in which walnut rootstocks RX1 (J. regia x J. microcarpa) were connected or not by a common mycelial network (CMN) to maize plants grown under two contrasting Pi levels. Mycorrhizal colonization parameters showed that the inoculum reservoir formed by inoculated walnut donor saplings allowed the mycorrhization of maize recipient roots. Relative to non-mycorrhizal plants and whatever the Pi supply, CMN enabled walnut saplings to access maize Pi fertilization residues according to significant increases in biomass, stem diameter and expression of JrPHT1;1 and JrPHT1;2, two mycorrhiza-inducible phosphate transporter candidates here identified by phylogenic inference of orthologs. In the lowest Pi supply, stem height, leaf Pi concentration and biomass of RX1 were significantly higher than in non-mycorrhizal controls, showing that mycorrhizal connections between walnut and maize roots alleviated Pi deficiency in the mycorrhizal RX1 donor plant. Under Pi limitation, maize recipient plants also benefited from mycorrhization relative to controls, as inferred from larger stem diameter and height, biomass, leaf number, N content and Pi concentration. Mycorrhization-induced Pi uptake generated a higher carbon cost for donor walnut plants than for maize plants by increasing walnut plant photosynthesis to provide the AM fungus with carbon assimilate. Here we show for the first time that CMN alleviates Pi deficiency in co-cultivated walnut and maize plants, and may therefore contribute to limit the use of chemical P fertilizers in agroforestry systems.
... The soil structure modulates the growth and survivability of wetland plants. The soil texture also influences the bioavailability of pollutants, for example, clay can hold particles more readily compared to sand (Brady and Weil, 1999). ...
Constructed wetlands with improved and engineered phytoremediation technology are aesthetically pleasing methodologies. These are advantageous and handy for the removal of various wastes, viz., metals, textile dyes, pesticides, pharmaceutical wastes, organic compounds, polyaromatic hydrocarbons, landfill leachates, etc. Wetlands have become an increasingly accepted corridor to progress the waste handling capacity. This book chapter reports designs and configurations for engineered constructed wetlands for the degradation and elimination of various noxious wastes. It also reveals the role of various phytoremediators and microbes in developing wetland systems in reducing loads of various harmful chemicals. Phytoremediation is a naturally comprehensive technology and its application in High-Rate Transpiration Systems for the textile discharge treatment along with the development of the aesthetically pleasant wetland system. The literature in the book chapter is intended to comprehend phytoremediation in planned wetland systems and form an operational context for further hassle-free uses.
... The lime (Easy Spread dolomitic limestone) was supplied by Mosher Limestone Co. Ltd. (Upper Musquodoboit, NS, Canada). The rates of lime were applied to change the soil pH from 6.2 to 6.5 (low) and to 7.0 (high) based on the calculation in [30]. ...
The intensive use of lead (Pb)-based insecticides (lead arsenate, PbHAsO4) has led to Pb accumulation in agricultural soil, endangering human health through the possibility of transferring it to the food chain. The aim of this study was to evaluate the potential for the immobilization of Pb in the soil by applying organic (sludge, biocompost, yard compost, and peat) and inorganic (bone-meal, zeolite, lime, and wood ash) amendments, in combination with diammonium phosphate (DAP) in a greenhouse experiment. Two amendment rates were used: low and high, and three rates of DAP: 0 (zero), low (0.25 g of DAP/kg soil), and high (1.25 g DAP/kg soil). The results showed that the dry yield of carrot (Daucus carota susp. sativus) was the highest for the organic amendments in combination with the low rate of DAP. The high rate of inorganic amendments also increased the yield. Applications of inorganic bonemeal, inorganic lime, and inorganic wood ash yielded the lowest Pb tissue concentration (TC), and organic peat had the highest Pb TC. Inorganic bonemeal combined with DAP most effectively immobilized Pb in soil.
Improving food security strategies on highly degraded soils has become a significant challenge for South Africa. The need to secure food sources for the growing population under harsher climatic conditions is crucial. South Africa is one of the many water-scarce countries and is labeled the 30th driest country in the world. Numerous methods exist to enhance and maintain soil quality, including applying fertilizers and geological materials to the soil. Basalt has been the focus of numerous long-term studies on soil fertility. The focus of this review paper is to determine the utility of augmentation with rock dust in terms of benefits to soil properties during the weathering of primary minerals. This review paper includes a background on the current situation in South Africa regarding soil and climatic conditions and how the usage of rock dust can improve the situation at hand. With the demand placed on food production by a growing population and water scarcity in South Africa, it becomes evident that it is necessary to search for new innovative methods to improve soil quality in South Africa. The potential for basalt remineralization and application on non-arable soil in South Africa holds enormous economic benefits.
Soil properties are an outcome of the interplay between different soil forming factors and processes of which topography or altitude plays an important role. A study was conducted in the mid-Himalayan region to verify the impact of altitude on different soil properties. Geo-referenced soil samples were collected from 0–20 cm depth from the agricultural fields with an altitudinal variation of 760 m to 1170 m above mean sea level (amsl). Soils of the area were dominantly gravely sandy loam texture; moderately to highly acidic in reaction with low soluble salts and very high soil organic carbon (SOC) content. Soil fertility of the region was high in available phosphorous (P), relatively medium to high in available nitrogen (N), whereas, potassium (K) content was in medium range. Among the micronutrients, deficiencies were recorded for boron (B) and manganese (Mn), whereas, zinc (Zn), iron (Fe) and copper (Cu) content were high. It was observed that altitude had little/variable control over pH, EC, P, Cu, Mn, S and Fe distribution, whereas increasing trend of SOC, Zn, B, K and N content with altitude could be attributed to management practices and the effect of soil erosion and deposition at different altitude. The study indicated that the chemical and physical properties of soils were selectively affected by the altitudinal variations and are an important base for initiating scientific management of soil resources in the area.
Duke University); Owen Plank (University of Georgia)
- Dan Richter
Dan Richter (Duke University); Owen Plank (University of Georgia);
The State University of New Jersey)
- Joseph Heckman
- Rutgers
Joseph
Heckman (Rutgers, The State University of New Jersey);
I deeply appreciate the good humor, forbearance, and patience of my wife, Trish, and those students and colleagues who may have felt some degree of neglect as I focused so much of my energy, time, and attention on this labor of love
- Last
Last, but not least, I deeply appreciate the good humor, forbearance, and patience
of my wife, Trish, and those students and colleagues who may have felt some degree
of neglect as I focused so much of my energy, time, and attention on this labor of love.
RRW
College Park, Maryland, USA
February 2016