The Influence of Organic Matter on Soil Aggregation and Water Infiltration

ArticleinJournal of Production Agriculture 2(4):290 · January 1989with 254 Reads
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Abstract
The unimpeded flow of water down through the soil is essential to agricultural production. Intensive cultivation can disrupt soil structure and restrict infiltration, which results in inefficient water and land use. In this review, the effects of organic matter on soil aggregation and water infiltration are discussed at several levels. Organic amendments (manure, plant residue, and synthetic polymers) are reported to increase soil organic matter (fulvic acids, humic acids, and polysaccharides) which binds soil particles together into aggregates. When soil structure is improved through aggregation, the resulting pore size distribution favors the downward flow of water in soil (infiltration). Mechanisms that link these components (e.g., organic amendments, polysaccharide production, aggregate formation, and increased infiltration) are suggested and management options that improve water infiltration rates are proposed. Please view the pdf by using the Full Text (PDF) link under 'View' to the left. Copyright © 1989. . Copyright © 1989 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, 5585 Guilford Rd., Madison, WI 53711 USA

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    Composting of beef cattle (Bos Taurus) manure may increase the soluble salt (Ca, Mg, Na, K) and total sulfur (S) content and increase transport through the soil. Little research has been conducted on comparing transport of these chemicals through soil amended with composted (CM) manure versus fresh feedlot manure stockpiled for up to two months (FM). Our objective was to determine if the transport of these chemicals was greater for CM compared to FM when annually applied at 77 Mg ha−1 dry wt. for nine years to a clay loam soil. Intact soil cores were taken from a field experiment in the spring of 2007. Deionized water was applied to the soil cores in the laboratory under steady-state (4.9 cm d−1) and unsaturated conditions. Residual chemical concentrations in effluent were measured and breakthrough curves and cumulative mass loss curves obtained. The peak concentrations of K and total S; flow-weighted mean concentration (FWMC) and mass loss for Na, K, and total S; and recovery of Mg, Na, K, and total S were significantly (P ≤ 0.05) greater for CM compared to FM. However, peak concentrations, FWMCs, and mass loss of Ca and Mg were similar for both manure types. Treatment effects on these two soluble salts were likely masked by high natural Ca and Mg already in the soil. Analysis of co-variance also suggested greater cumulative mass loss of most chemicals (except Ca) for CM than FM at pore volumes between 0.25 and 2.5. However, our findings could not be explained by the differences in chemical content of the amendments or soil, or greater cation exchange capacity for CM than FM. The greater unsaturated hydraulic conductivity (at 7 mBar) of soil amended with CM compared to FM was the likely cause of greater transport of Na, K, and total S; and may be related to a physical effect of finer particles increasing water flow for composted manure.
  • Article
    Full-text available
    The objective of this experiment was to investigate the possibility on agricultural use of muncipal sewage sludge with respect to heavy metal contents in Korea. Metal contents (mg/kg) in 88 sludge samples were ranged from 0 to 54.3 for As, 1,7 to 197.3 for Cd, 7.3 to 2,854 for Cr, 87.4 to 5,730 for Cu, 129.3 to 10,289 for Mn 20.1 to 2,057 for Ni, 7.6 to 197.5 for Pb, and 523.5 to 6,349 for Zn. Heavy metal contents of sludges were compared with the regulation on raw material for compost. All sludges produced from sewage treatment plane in metropolis (over a million in population) and large cities () were not compatible with the regulation. In addition, 95% of sludge from small and mid-size cities () and 93% from rural area (below 100,000) were not suitable. On the basis of Cd, Cu, Ni and Zn contents, 41, 53, 47, and 89% of sludge samples were not compatible with the regulation on raw material for compost respectively.
  • Article
    Soil cracks can enhance water recharge through preferential flow during the rainy season and enhanced evaporation loss during the post-rainy season. Despite their significance, a limited information is available on the management of surface cracks in Vertisols. The frequency, size, and rate of development of cracks greatly affect the movement of soil water and nutrient and exchange of gases in the soil profile and also influence plant growth processes in Vertisols. To find out the suitable soil amendments and land use for reducing the rate of crack formation in medium-deep black soils of the region, a 4-year field experiment was conducted to evaluate the effect of different soil amendments and land uses on surface cracks, soil properties and crop yields on Vertisols under semiarid conditions. Field experiment consisted of three different land uses [i.e., agriculture [intercropping of sorghum (Sorghum biocolor L.) + pigeon pea (Cajanus cajan L.) at 1:1 ratio], grassland (dhaman grass—Cenchrus ciliaris L.), fallow land (no cultivation fallow)] as main plots with four different soil amendments [i.e., S0—control, S1—fly ash @ 10 Mg ha⁻¹, S2—crop residue (wheat straw) @ 5 Mg ha⁻¹, S3—gypsum (100% of gypsum requirement), S4—FYM @ 5 Mg ha⁻¹] as subplots. The data showed that application of soil amendments had a beneficial effect on soil properties such soil pH, available nutrients, labile C and total organic carbon and stocks. In the 0–15-cm layer, SOC stocks varied from 15.17 to 20.04; 16.13–20.67; 14.25–19.58 Mg ha⁻¹ for agriculture, grassland and fallow land, respectively. The labile C and total organic carbon contents were in the order of grassland > agriculture > fallow land. Further, soil under grassland system recorded the higher mean weight diameter than that under crop and fallow land. Among different soil amendments applied, wheat straw and FYM had a significant effect (P < 0.05) on soil aggregation. Application of amendments increased soil moisture content by 5.7–12.6; 2.2–13.3; 9.0–17.3% over control (no soil amendments) for agriculture, grassland and fallow land use system, respectively. Among different land uses, crack volume reduction was in the order of grassland (− 7 to − 44%) > agriculture (− 7 to − 18%) > fallow land (− 2 to − 23%). Wheat straw application registered the lowest crack volume followed by that under FYM, fly ash and gypsum, regardless of the land use systems. Crop and grass biomass yields were significantly (P < 0.05) affected by the application of soil amendments. Application soil amendments not only reduced crack volume but also favorably influenced soil properties and crop yields in Vertisols.
  • Article
    Resumen The objective of this study was to determine how rangeland hydrology of oak, juniper, bunchgrass and shortgrass vegetation types is altered by fire. The research was conducted at the Sonora Agricultural Experiment Station on the Edwards Plateau, Texas. Infiltration rate and interrill erosion were measured using a drip-type rainfall simulator. Terminal infiltration rates of unburned areas were significantly greater on sites dominated by oak (Quercus virginiana Mill.) (200 mm hour-') or juniper CJuniperus ashei Buchh.) (183 mm hour-') than on sites dominated by bunch-grass (146 mm hour-') or shortgrass (105 mm hour-'). Terminal infiltration rates on burned areas were significantly reduced on sites dominated by bunchgrass (110 mm hour-'), shortgrass (76 mm hour-'), and on oak sites that were cut and burned (129 mm hour-'). Soil organic matter content (r = .61), total organic cover (r = .59), and aggregate stability (r = 53) were the variables most strongly correlated with infiltration rate. Measured soil structure properties were not altered by fire, therefore, differences in infil-tration rate between unburned and burned treatments were attributable to variations in the amount of cover. The terminal infiltration rate of cut and burned juniper sites (162 mm hour-') was not changed significantly after the Rre because the associated good soil structure properties allowed rapid infiltration even after cover was removed. Good soil structure properties were also pre sent on the oak sites, but the infiltration rate significantly decreased as a result of the temporary hydrophobic nature of the soil on this site after burning. Prior to burning, interrill erosion was much lower under the tree sites (oak = 2 kg ha-'; juniper = 34 kg ha-') than on bunchgrass (300 kg ha-') or shortgrass (1,299 kg ha-') sites. After burning, interrill erosion significantly increased for all vegetation types (shortgrass = 5,766 kg ha-'; bunchgrass = 4,463 kg ha-'; oak = 4,500 kg ha-'; juniper = 1,926 kg ha-'). Total organic cover (r = -.74) and bulk density at O-30 mm (r = .46) were most strongly correlated with interrill erosion.
  • Article
    A four-state study was initiated in 1988 to evaluate the influence of cultivation frequency and initiation on the cotton plant. When cultivations were initiated at 1 or 2 wk after emergence and cultivated weekly at a frequency of zero, one, two, four, or six times, seed cotton yields were not affected on a consistent basis. When averaged over cultivation frequency, seed cotton yields were increased for three of nine year-locations when cultivations were initiated at 2 wk after emergence when compared with 1 wk after emergence. At two locations, when seed cotton yields were averaged over initiation timing, it was shown that only two cultivations were necessary to achieve optimum seed cotton yields.
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    Full-text available
    Land application of composted feedlot cattle (Bos taurus) manure may have differential effects on soil physical properties compared to stockpiled manure because of the differences in the composition, particle size, and decomposability of these materials. Our objective was to determine the effect of long-term (9 yr) composted (CM) versus stockpiled (SM) manure application on selected soil physical properties. Intact soil cores were taken from CM, SM, and unamended control treatments from a long-term field experiment in the fall of 2007. Soil bulk density, plant available water (PAW), and soil water retention and hydraulic conductivity at low (0–34 kPa) water potentials were determined on the soil cores. Water retention at the 0 to 10 cm depth was significantly (P ≤ 0.05) greater for SM than CM between -5 and -34 kPa, suggesting an increase in transmission and storage pores in the SM treatment. In contrast, water retention at the 10 to 20 cm depth was greater for CM than SM at -1 and -5 kPa, indicating an increase in transmission pores for this treatment. Based on the results of our study, application of CM instead of SM will likely not improve most soil physical properties measured, with the exception of water retention at certain water potentials in the top two depths. However, organic amendments will likely improve most soil properties measured compared to unamended soils.
  • Article
    Pig (Sus scrofa) manure is added to the soil to supply nutrients and improve soil properties. To our knowledge, no direct comparison has been made on the effect of liquid pig manure (LPM) and solid pig manure (SPM) on the physical properties of a prairie soil. This study was established in 2009 at the University of Manitoba’s Ian Morrison Research Station in Carman, Manitoba. The treatment design was a split-plot structure with cropping system as the main plot and manure treatments as subplots. Five years after the study was initiated, soil samples were collected from the 0-10 cm and 10-20 cm depth intervals for determination of bulk density, saturated hydraulic conductivity (Ksat), and water retention at field capacity and permanent wilting point (PWP). For wet aggregate stability, samples were collected from the 0-5 cm layer. Land application of SPM significantly decreased bulk density by 14%, significantly increased Ksatby 110% in the 0-10 cm layer, and resulted in a 30% increase in wet aggregate stability (P < 0.05). In perennial plots, SPM increased water retention at field capacity, PWP, and available water in the 0-10 cm compared with annual plots. This was not the case for LPM-amended soils. We conclude that SPM has the potential as an organic amendment to improve the physical properties of the topsoil.
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    Cotton yield response was evaluated in 1987, 1988, and 1989 when weeds were managed with preemergence fluometuron [none (0%), band (50%), or broadcast (100%) surface coverage], cultivation (none, one, two, or three times), and postdirected fluometuron + MSMA. Weed densities (primarily prickly sida, morningglories, and hemp sesbania) varied widely among years and were directly related to early season rainfall. Postdirected herbicide application or cultivation(s) had little effect on weed density. The use of a banded fluometuron application reduced weed biomass 28 to 47%. A further decrease was observed when preemergence fluometuron was increased from banded to broadcast coverage. Seed cotton yields were low with no preemergence fluometuron. Banded fluometuron and at least one cultivation had yields similar to broadcast fluometuron only. Cotton yields were related to weed density and weed biomass in a hyperbolic relationship. Low weed densities caused more yield loss per unit weed density than higher densities.
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    Elevated uranium dose (4 g kg⁻¹) causes a shift in billabong sediment communities that result in the enrichment of five bacterial species. These taxa include Geobacter, Geothrix and Dyella species, as well as a novel—potentially predatory—Bacteroidetes species, and a new member of class Anaerolineae (Chloroflexi). Additionally, a population of methanogenic Methanocella species was also identified. Genomic reconstruction and metabolic examination of these taxa reveal a host of divergent life strategies and putative niche partitioning. Resistance-nodulation-division heavy metal efflux (RND-HME) transporters are implicated as potential uranium tolerance strategies among the bacterial taxa. Potential interactions, uranium tolerance and ecologically relevant catabolism are presented in a conceptual model of life in this environment.
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    The highly weathered, mineral, and often eroded and acidic soils of the Ozark Highlands region of northwest Arkansas generally have low soil organic matter (SOM) concentrations as a result of rapid organic matter turnover rates in the warm, moist climate. Orchard management practices that can improve SOM may also improve other soil quality-related variables for sustained production, which is an explicit goal for the National Organic Program (NOP). Therefore, beginning in Mar. 2006 and continuing for seven seasons, annual applications of municipal green compost, shredded office paper, wood chips, and mow-blow grass mulch groundcover management systems (GMS) in combination with composted poultry litter, commercial organic fertilizer, or a non-fertilized control as a nutrient source were implemented to evaluate their ability to alter near-surface soil quality in a newly established, organically managed apple orchard in the Ozark Highlands region of northwest Arkansas. The SOM concentration in the top 10 cm averaged 1.5% across all treatments at orchard establishment in 2006, but by 2012, SOM concentration had increased in all GMS and more than doubled to 5.6% under green compost. Similarly, soil bulk density in the top 6 cm, which averaged 1.34 g.cm(-3) among treatment combinations in 2006, decreased in all GMS by 2012. Either green compost or shredded paper had the largest concentration of total water-stable aggregates across all aggregate size classes in the top 7.5 cm, whereas no differences among GMS were observed in the 7.5- to 15-cm soil depth. Green compost applied alone or in combination with commercial fertilizer had the largest estimated plant-available water (17.9% v/v) among all treatment combinations. Many soil quality-related variables measured in the various organic GMS had numerically greater values compared with an adjacent conventionally managed orchard on the same soils. Implementation of these GMS appears to provide apple producers in the Ozark Highlands and similar regions a tangible means of meeting NOP requirements for improving soil quality concurrent with production of certified organic crops. The findings also have implications for conventionally managed orchards, which have maintaining or improving soil quality as a management goal.
  • Article
    In Tunisia, the lowest soil organic carbon stocks are attributed to arid soils. This study was conducted to assess and to quantify soil organic carbon (SOC) stocks and pools under oases agrosystems in arid regions of Tunisia. Soil samples were collected from 0- to 5-cm and from 0- to 30-cm layer depth from two principal types of soils (Lithosols and Solonchaks) under three oases. Total SOC, particulate organic carbon (POC) and SOC < 50 µm content and stocks were calculated. The results showed that Lithosols contain the highest SOC content (1.11%). However, Solonchaks accumulate the highest POC. Both Lithosols and Solonchaks store large amount of SOC < 50 µm. Particularly in 0–5-cm layer, negative and significant correlation was found between POC and bulk density (BD) in Lithosols but in Solonchaks POC was positively correlated with BD. On average SOC stocks in Lithosols in 0–5-cm layer are above those calculated for Solonchaks and not exceed 0.81 kg C/m2. The greater SOC stocks in 0–30 cm depth characterize Lithosols (4.33 kg C/m2). SOC stocks for Solonchaks were below 3.19 kg C/m2. Otherwise, differences in POC stocks were observed in 0–30-cm layer between soils. Solonchaks store between 0.98 and 1.24 kg C/m2 of POC. The proportion of POC stocks relative to the total SOC stock is <25% in two types of soil. Organic carbon stocks are mostly stable, as SOC < 50 µm stocks reached over 70% of SOC. We can suggest that arid soils have high capacity to store organic carbon under oasis agrosystems.
  • Article
    Understanding the environmental impact of bioenergy crops is needed to inform bioenergy policy development. We determined the effects of five biomass cropping systems—continuous maize (Zea mays), soybean (Glycine max)-triticale (Triticosecale ×)/soybean-maize, maize-switchgrass (Panicum virgatum), triticale/sorghum (Sorghum bicolor), and triticale-aspen (Populus alba × P. grandidentata)—on soil-saturated hydraulic conductivity (KS) across a toposequence in central Iowa, USA. We compared data from the time of cropping system establishment in 2009 to 4 years post-establishment. Both our 2009 and 2013 data confirmed that cropping system impacts on KS vary by landscape position. We found that differences in cropping system impacts were more likely to occur at lower landscape positions, specifically, within footslope and floodplain positions. Previous research on cropping system impacts suggested that grass and woody systems were associated with a general increase in KS over time, with greater changes likely occurring at landscape positions with a higher erosive potential or lower SOC content. Our results confirmed that the triticale-aspen woody system was associated with a significant increase in KS across all landscape positions. In contrast, we did not observe an increase in KS under maize-switchgrass, which we attributed to the high density of switchgrass roots by the fourth year of study, but expect an increase in KS under switchgrass under longer measurement periods. We also found a significant increase in KS in the annual systems, likely due to the conversion to no-till soil management with cropping system establishment. We expect such differences to become more apparent over longer time scales as cropping systems continue to impact soil hydraulic properties.
  • Article
    This study was performed to investigate the possible uses of waste sludge for the removal of heavy metal ions. The adsorption experiments were conducted with wastes such as sewage treatment sludge, water treatment sludge and oyster shell to evaluate their sorption characteristics. Heavy metals selected were cadmium, copper and lead. in the sorption experiments on the sewage treatment sludge, water treatment sludge, oyster shell and soil, sorption occurred in the beginning and it reached equilibrium after 40 minutes on the oyster shell and 4 hour on the sewage treatment sludge and water treatment sludge. Results of Freundlich isotherms indicated that sewage treatment sludge could be properly used as an adsorbent for heavy metals and sorption strength of heavy metals was in the order of Pb > Cu > Cd. In the influence of pH on the adsorbents, sorption rate was more than 80% in pH 4 and most of heavy metals were adsorbed in pH 9. Adsorption rate of Cd decreased with decreasing pH and then adsorption rate of Cu was lower in soil.
  • Article
    This study was carried out on 'Tombul' hazelnut orchards between 2001 and 2007 to evaluate the long-term effects of hazelnut husk compost (HHC) on soil permeability. The amendments were only applied in 2001. The experimental design was replicated three times with four doses as a randomized complete block of hazelnut husk compost. The amendment was applied at rates of 0, 20, 40, 80 and 120 ton ha-1 dry weight replicated. During the experiment, disturbed and undisturbed soil samples were collected once a year. Hydraulic conductivity, water retention capacity, available water content, porosity, percent of macro-pore and micro-pore and some soil properties were determined. Organic material applications increased the hydraulic conductivity of the soil, but this effect declined in the long term. In the first year, compost applications amended selected soil properties. On the other hand, this positive effect decreased in the six years depending on the decomposition of the hazelnut husk compost.
  • Article
    Stevia rebaudiana Bertoni is a promising crop for semiarid climates, including Algarve region. The objectives of this work were: to compare the feasibility of the eco-friendly stevia weed control strategy with a compost of vegetable residues (grass clippings and pruning’s); to identify the emerged weed species, and to evaluate the effect of compost application on soil properties. Treatments consisted on the application of a 5 cm layer of compost on soil surface or incorporated, and no compost application as control. The trial was set up in six randomized field plots, with four replications. Each plot was divided into three subplots, with one treatment per subplot, in a total of 24 subplots per treatment. Compost application had a distinct effect on weed species. Some species were significantly reduced when compost was applied, namely as mulch. Compost increased soil water content, mainly in area of the trial with lower soil drainage, especially when compost was applied as mulch, as well as other physical and chemical soil properties. Results showed the positive effect of compost on weed control and soil properties during stevia cultivation.
  • Chapter
    Hydrologic attributes which influence ecosystem structure and function include infiltration rate, soil moisture storage capability, precipitation characteristics and rain use efficiency. The degree to which these hydrologic attributes are affected by land use determines the impact of the land use on the ecosystem. Simply removing the initial cause of degradation may not restore the site’s production potential, and may not even break the pattern of decline if a self-sustaining cycle of deterioration has developed. Reasons why severely disturbed landscapes may not recover production potential include loss of species, altered species interactions, physical degradation of hydrologic characteristics or nutrient depletion. The economic realities associated with rangeland ecosystem management restrict implementation of widespread restoration strategies requiring intensive management. Therefore both ecological and economic challenges must be solved if restoration is to proceed. A watershed is a natural scale of resolution which provides a logical context for addressing the ecological and economic challenges of restoration. The drainage patterns of a watershed form the framework of energy and nutrient flow that must be understood to address the ecological considerations of management strategies. These flow patterns also provide the context for a more complete (and more favorable) socioeconomic accounting of the serial benefits and costs of investments in rangeland management.
  • Article
    Full-text available
    Large, volume-based applications of composted municipal biosolids (CMB) can enhance turfgrass growth and quality and soil physical and chemical properties. In addition, CMB additions could affect short-term dynamics of soil organic carbon (SOC) and enhance C sequestration and environmental quality compared with turfgrass fertilized with inorganic nutrients in mineral soil. The objective was to compare changes in SOC among contrasting sources of Tifway bermudagrass sod (Cynodon dactylon L. Pers. × C. transvaalensis Burtt-Davey) after transplanting. Three sod sources from fields grown with two commercial sources of CMB or inorganic phosphorus fertilizer were transplanted on silica sand in replicated box lysimeters. Storage of SOC within 0 to 5-cm and 5 to 50-cm depths was greater in CMB than fertilizer-grown sod during 10 months of establishment and maintenance. Leaching losses of dissolved organic C (DOC) were two times greater for CMB than for fertilizer-grown sod over seven simulated rain events, but the ratio of DOC in leachate to total SOC mass was 0.3% or less for CMBgrown sod. An increase in d13C values of SOC over sampling dates indicated the proportion of SOC derived from turfgrass increased, whereas that from CMBdecreased. The benefit of greater rates of SOC storage during establishment and maintenance of CMB compared with fertilizer-grown sod was achieved without substantive loss of DOC in leachate.
  • Article
    In this study, the effects were investigated of salinity, foliar and soil applications of humic substances on the growth and mineral nutrients uptake of Corn (Hagein, Fardy10), and the comparison was carried out of the soil and foliar applications of humic acid treatments at different NaCl levels. Soil organic contents are one of the most important parts that they directly affect the soil fertility and textures with their complex and heterogenous structures although they occupy a minor percentage of the soil weight. Humic acids are an important soil component that can improve nutrient availability and impact on other important chemical, biological, and physical properties of soils. The effects of foliar and soil applications of humic substances on the plant growth and some nutrient elements uptake of Corn (Hagein, Fardy10) grown at various salt concentrations were examined. Sodium chloride was added to the soil to obtain 20 and 60mM saline conditions. Solid humus was applied to the soil one month before planting and liquid humic acids were sprayed on the leaves twice on 20th and 40th day after seedling emergence. The application doses of solid humus were 0, 2 and 4 g/kg and those of liquid humic acids were 0, 0.1 and 0.2%. Salinity negatively affected the growth of corn; it also decreased the dry weight and the uptake of nutrient elements except for Na and Mn. Soil application of humus increased the N uptake of corn while foliar application of humic acids increased the uptake of P, K, Mg,Na,Cu and Zn. Although the effect of interaction between salt and soil humus application was found statistically significant, the interaction effect between salt and foliar humic acids treatment was not found significant. Under salt stress, the first doses of both soil and foliar application of humic substances increased the uptake of nutrients.
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