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soilaggregates, etc ; data collection; landscapes; models; soil structure; Show all 5 Subjects
Abstract:
... Soil aggregate size distribution (ASD) is a key soil property for quantitative characterization of soil structure. Typically, dry and wet sieving methods are followed to measure mass fractions of soil aggregates under each aggregate size class and their cumulative fractions are used to estimate ASD parameters. In general, available soil ASD databases are small and a comprehensive assessment of exi ...
soilaggregates, etc ; ethanol; prediction; rain; research; splash erosion; temperature; tillage; Show all 8 Subjects
Abstract:
... The influence of raindrop temperature on the soil erosion process has been reported. However, the role of raindrop temperature in aggregate disintegration is unclear. The aims of this study are to investigate the effects of raindrop temperatures on soil aggregate disintegration and to evaluate their effects on the contribution of slaking and mechanical striking to splash erosion. Deionized water a ...
soilaggregates, etc ; Mollisols; electrolytes; rain; rainfall simulation; splash erosion; China; Show all 7 Subjects
Abstract:
... Soil internal forces can affect aggregate breakdown, and then impact splash detachment and transport of aggregate fragments. However, currently, the processes of soil splash detachment and transport under different soil internal forces are still not fully understood. Thus, to determine the effects of soil internal forces on the splash transport process, two soils (Binxian soil and Keshan soil) in ...
soilaggregates, etc ; carbon; mulches; no-tillage; straw; stubble; wheat; South Africa; Show all 8 Subjects
Abstract:
... Soil aggregate dynamics have received renewed interest due to their relevance in carbon (C) stabilisation. This study evaluated changes in aggregate-size distribution and intra-aggregate C following 41 years of wheat production in semi-arid central South Africa. Management practices that have been applied for 41 years include two straw management protocols (unburned and burned), three tillage syst ...
soilaggregates, etc ; grasslands; microbial carbon; nitrogen; soil organic carbon; stoichiometry; China; Show all 7 Subjects
Abstract:
... Soil microbial carbon use efficiency (CUE) plays a crucial role in terrestrial C cycling. However, how microbial CUE responds to nitrogen addition and its mechanisms in soil aggregates from abandoned grassland systems remains poorly understood. In this study, we designed a nitrogen (N) addition experiment (0 (N0), 10 (N1), 20 (N2), 40 (N3), 80 (N4) kg N ha⁻¹yr⁻¹) from abandoned grassland on the Lo ...
soilaggregates, etc ; aggregate stability; air drying; labor; prediction; research; soil water; tillage; Show all 8 Subjects
Abstract:
... Aggregate stability (AS) is an important parameter to evaluate soil resistance to erosion. The conventional determination methods to measure AS are time consuming, difficult and labour intensive. Visible (vis) and near infrared (NIR) spectroscopy could be a better alternative to the conventional determination methods of AS. This study explored the possibilities of estimating three AS indices, refl ...
soilaggregates, etc ; Weibull statistics; arable soils; friction; porosity; research; tensile strength; tillage; Show all 8 Subjects
Abstract:
... The Discrete Element Method (DEM) is a suitable approach for modeling and simulating arable soil and tillage processes. In this work, we focus on modeling soil fragmentation which is a vital element of many soil treatments. We present a method for computing the indirect tensile strength of soil aggregates through simulation. DEM aggregates are constructed as spherical clusters of smaller spherical ...
soilaggregates, etc ; aggregate stability; drought; edaphic factors; farms; forests; nitrification; nutrient availability; soil respiration; China; Show all 10 Subjects
Abstract:
... Wetting dry soil is well known for generating respiration and nutrient pulses (the “Birch effect”), but the effects of frequent drying-rewetting (DRW) cycles, especially the effects regarding nutrient availability, have not been well investigated. This study was designed to determine how DRW frequency influences soil respiration, aggregate stability and nutrient availability. Soil was collected fr ...
soilaggregates, etc ; aggregate stability; cations; rain; rainfall simulation; research; salt concentration; splash erosion; water conservation; Show all 9 Subjects
Abstract:
... Soil interparticle forces can pose important effects on soil aggregate stability and rainfall splash erosion. Meanwhile, these interparticle forces are strongly influenced by specific ion effects. In this study, we applied three monovalent cations (Li⁺, Na⁺, and K⁺) with various concentrations to investigate the influence of specific ion effects on aggregate stability and splash erosion via pipett ...
... Preservation of biochemically recalcitrant organic matter and protection within soil aggregates are two important mechanisms of soil organic carbon (SOC) preservation, but their relative importance remains unclear. In this study, we converted part of a mature secondary forest to two young plantation forests (Castanopsis carlesii and Chinese fir) and an assisted naturally regenerated (ANR) forest i ...
soilaggregates, etc ; carbon; catenas; field capacity; freeze-thaw cycles; nitrogen; phosphorus; risk reduction; total nitrogen; water content; Show all 10 Subjects
Abstract:
... Available information about the effects of freeze–thaw cycles (FTCs) and soil aggregate structure on the mobility of phosphorus (P) fractions is limited. Here, soil column experiments with different initial moisture contents (saturated moisture content and field capacity) were used to study the redistribution of P fractions in soil aggregates after 0, 2, 5, and 10 freeze–thaw cycles. The results s ...
... Small changes in soil aggregates-associated organic carbon (OC) can induce huge fluctuations in greenhouse gas emissions. However, there is a knowledge gap on the responses to nitrogen (N) fertilization under plastic film mulching, especially in long-term continuous rotation systems. This study assessed the impacts of plastic film mulching and N fertilization on the soil aggregate distribution and ...
... Microplastics (MPs) have become a problematic pollutant in different environments. Dry soil aggregates may have a remarkable influence on the emissions of MPs from surface soil due to wind erosion. Here, we sampled surface soils and monitored wind erosion events to investigate the number of MPs distributed in different dry soil aggregate sizes and the implications for MP emissions induced by wind ...
... Studying the internal structure of soil aggregates is an insightful way to improve the understanding of soil aggregation process. However, it is still not clear how the macroaggregate pore structure is influenced by the application of long‐term tillage practices. In this study, we aimed to determine the differences in macroaggregate pore structure among long‐term tillage practices using micro‐comp ...
... The progression of water erosion patterns from rill to gully erosion significantly affects the level of soil aggregate degradation, and thereby stimulates variations in the biochemical mechanisms controlling the OC mineralization ratio. These conditions can affect the exchange of carbon from biosphere to atmosphere. We examined the effect of erosion progression on the physical and biochemical soil ...
soilaggregates, etc ; aggregate stability; conventional tillage; corn; irrigation; land degradation; no-tillage; saturated hydraulic conductivity; seals; soil organic carbon; Show all 10 Subjects
Abstract:
... The effect of no‐tillage (NT) (zero tillage) versus conventional tillage (CT) has been evaluated in rainfed conditions but has seldom been studied under irrigation, where soil sealing favours soil degradation. To contribute to this knowledge, this research analyses soil aggregate stability under disaggregation forces produced under irrigation (causing slaking and mechanical breakdown) and the susc ...
soilaggregates, etc ; afforestation; aggregate stability; atmospheric precipitation; catenas; cropland; ecological restoration; nitrogen; phytomass; soil organic carbon; total nitrogen; China; Show all 12 Subjects
Abstract:
... Vegetation restoration is an important factor affecting soil carbon (C) and nitrogen (N) sequestration. However, the effects of the type of vegetation restoration on soil C and N sequestration varies owing to different environmental conditions. Therefore, additional studies should explore the effects of vegetation restoration type on soil C and N sequestration, especially between natural restorati ...
... Pore structure can reflect the soil aggregation process, determine various physical, chemical and biological processes in aggregates. This study investigates variations in the intra-aggregate microstructure (porosity, pore size distribution, and pore shape) of six different weathered soils across temperate (Haplic Phaeozems, HP; Haplic Luvisols, HL; Calcic Luvisols, CL), subtropical (Ferric Luviso ...
soilaggregates, etc ; Cystobacteraceae; Polyangiaceae; community structure; myxobacteria; pollution; research; soil bacteria; straw; straw mulches; sustainable agriculture; total organic carbon; wastes; Show all 13 Subjects
Abstract:
... Crop straw mulching is an important organic supplement in sustainable agriculture; however, the effect of increased organic matter on the diversity of micropredators such as myxobacteria and the correlation between myxobacteria and microorganisms have been little explored. In the current investigation, high-throughput sequencing was performed to analyze the myxobacterial community composition in a ...
... Removal of crop residues for biofuel production can potentially increase the erodibility of a soil by not only exposing the soil surface to winds but also affecting changes in soil aggregation and roughness. Field studies at both Colby and Ottawa, Kansas were conducted to determine the effects of long-term residue removal on soil wind erodibility. Corn residue was removed from plots at 0%, 25%, 50 ...