An aggregate is a group of primary particles that cohere to each other more strongly than to other surrounding soil particles. Most adjacent particles adhere to some degree. Therefore, disintegration of the soil mass into aggregates requires imposition of a disrupting force. Stability of aggregates is a function of whether the cohesive forces between particles withstand the applied disruptive f...

Understanding the effects of soil intrinsic properties and extrinsic conditions on aggregate stability is essential for the development of effective soil and water conservation practices. Our objective was to evaluate the combined role of soil texture, aggregate size and application of a stabilizing agent on aggregate and structure stability indices (composite structure index [SI], the α and n ...

Najafi-Ghiri M., Abtahi A. (2013): Potassium fixation in soil size fractions of arid soils. Soil & Water Res., 8: 49–55. Amounts of potassium (K) fixed in soil fractions of 10 calcareous soils of southern Iran were measured to evaluate the contributions of different soil size fractions to K fixation. Soil particles were fractionated after dispersion of the soils with an ultrasonic probe. Potass...

Atrazine is still widely used in China. residue (1.86-1 100 mg/kg) the soil has exceeded allowable limit (1.0 mg/kg), affecting structure and aggregate composition. To understand long-term application of atrazine on aggregates binding agent, four treatments were established cornfield planted since 1998, including without applied (AT0), (28% atrazine, 1 200-1 350 mL/ha/year) once a year from 201...

The short term impact of 50 µM Hg(II) on soil bacterial community structure was evaluated in different microenvironments of a silt loam soil in order to determine the contribution of bacteria located in these microenvironments to the overall bacterial response to mercury spiking. Microenvironments and associated bacteria, designated as bacterial pools, were obtained by successive soil washes to...

Aggregates play a key role in protecting soil organic carbon (SOC) from microbial decomposition. The objectives of this study were to investigate the influence of pore geometry on the organic carbon decomposition rate and bacterial diversity in both macro- (250-2000 μm) and micro-aggregates (53-250 μm) using field samples. Four sites of contrasting land use on Alfisols (i.e. native pasture, cro...

Shaded perennial agroforestry systems contain relatively high quantities of soil carbon (C) resulting from continuous deposition of plant residues; however, the extent to which the C is sequestered in soil will depend on the extent of physical protection of soil organic C (SOC). The main objective of this study was to characterize SOC storage in relation to soil fraction-size classes in cacao (...

To determine the effects of straw incorporation on soil nutrients, enzyme activity, and aggregates in tobacco fields, we conducted experiments with different amounts of wheat and maize straw in Zhucheng area of southeast Shandong province for three years (2010–2012). In the final year of experiment (2012), straw incorporation increased soil organic carbon (SOC) and related parameters, and impro...