Soil wettability is especially important for rainfed agriculture in climates with a dry period during the growing season. The effect of aggregate structure and soil organic C content on wettability of soil aggregates was determined for grassland (grass) and tilled fields (tillage). Soil organic C, plastic limit, aggregate total porosity, and wettability at 100 mm (rapid wetting) and 300 mm (slo...

The impact of reforestation on soil organic carbon (OC), especially in deep layer, is poorly understood and deep soil OC stabilization in relation with aggregation and vegetation type in afforested area is unknown. Here, we collected topsoil (0-15 cm) and deep soil (30-45 cm) from six paired coniferous forests (CF) and broad-leaved forests (BF) reforested in the early 1990s in subtropical China...

Structure is an important factor of soil functioning in ecosystems. Soil aggregate size distributions are commonly used to characterize soil structure. Relationships between density of dry soil aggregates and aggregate size present a different way to use aggregate-related information in soil structure characterization. Those relationships have been simulated assuming soils to be mass fractals. ...

Soil aggregates include sand/silt/clay, water, ion and organic matter contents combined with natural dry/wet (D/W) cycling alters both the formation and function of intra-aggregate pore continuity, connectivity, dead-end storage volumes, and tortuosity. Surface aggregates in the 0-5 cm depths of most soils experience from 34 to 57 D/W cycles that exceed differences in water contents >10%. Both ...

soil organic carbon has been the most important soil quality measurement factors and has intense relation with soil physical, chemical and biological characteristics. organic matter and its components are important factors of soil aggregates constitution and stability and play significant role in its structure.so, this research has been done for achieving this purpose. this area is arounding sa...

Shear strength of aggregates and the bulk soil matrix in two Haploxeroll of central Chile was assessed in order to determine: (1) the effect of previous tillage on shear parameters between aggregates and in the soil matrix and (2) the effects of structure development on differences between dry-wet mechanical parameters. Undisturbed soil cylinders and single aggregates (0-10 cm layer) were colle...

Soil aggregate stability influences a wide range of physical and biogeochemical processes in the agricultural and natural environments, including soil erosion [3]. The relative prepon‐ derance of aggregates of various sizes in the soil and their stability to external forces are, therefore, an issue of major concern to soil scientists. By definition, an aggregate is a compo‐ site body or granule...

INTRODUCTION: The percentage of water stable aggregates (WSA) is a measure of resistance to breakdown by water and mechanical activities. Water stable aggregates improve soil water and air movement. Macro-aggregates (diam. > 250 m) are considered as a secondary soil structure associated with pores, microbial habitat, and physical protection of organic matter (Christensen, 2001; Carter, 2004). A...

a major concern of farmers is deterioration of the soil and water resources. soil management is the most direct way for mankind to interfere with natural processes that may either intensify or hinder soil degradation. fractal geometry has been widely used to describe heterogeneity in a wide range of natural processes, including physical systems of soil. in this study, the effects of different m...

*T. C. Caesar-TonThat and V.L. Cochran, USDA-ARS Northern Plains Agricultural Research Laboratory, 1500 North Central, Sidney, MT 59270 *Corresponding author: [email protected]. ABSTRACT Loss of water stable aggregates due to excessive tillage has increased the potential for soil erosion in semiarid farming-systems. Fungi can be responsible for the resistance of soil aggregates to brea...