Soil aggregates by design: Manufactured aggregates with defined microbial composition for interrogating microbial activities in soil microhabitats

Distribution of chromium contamination and microbial activity in soil aggregates.

Biogeochemical transformations of redox-sensitive chemicals in soils can be strongly transport-controlled and localized. This was tested through experiments on chromium diffusion and reduction in soil aggregates that were exposed to chromate solutions. Reduction of soluble Cr(VI) to insoluble Cr(II) occurred only within the surface layer of aggregates with higher available organic carbon and hi...

Size fractionation and microbial community structure of soil aggregates

The microbial community structure in various microaggregates in a loamy sand soil was investigated. The microaggregates were separated into outer and inner aggregates using a series of soil washes. Further physical fractionation of inner aggregates was achieved by separation into coarse and fine sand as macroaggregate fractions, coarse and fine silt as microaggregate fractions, and clay. Resear...

Long-term tillage effects on the distribution patterns of microbial biomass and activities within soil aggregates

Chromium diffusion and reduction in soil aggregates.

The distribution of metal contaminants such as chromium in soils can be strongly localized by transport limitations and redox gradients within soil aggregates. Measurements of Cr(VI) diffusion and reduction to Cr(III) were obtained in soil columns representing transects into soil aggregates in order to quantify influences of organic carbon (OC) and redox potentials on Cr transport distances and...

Changes study of soil splash and stability of soil aggregates using polyvinyl acetate

Soil erosion, especially water erosion, threatens the installations, water resources and also human life. The first stage of water erosion is the splash erosion that it requires to control in the primary stages. On the other hand, the application of soil conditioners is one of the approaches that it provide the conservation possibility of soil surface against water erosion, especially erosion f...