ARS | Publication request: Soil microbial parameters and stability of soil aggregate fractions under different grassland communities on the Loess Plateau, China

Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: September 21, 2009
Publication Date: September 24, 2009
Citation: An, S., Mentler, A., Acosta Martinez, V. 2009. Soil microbial parameters and stability of soil aggregate fractions under different grassland communities on the Loess Plateau, China[abstract]. 2nd International Conference Biohydrology. Bratislava, Slovakia. September 21-24, 2009.

Technical Abstract: Over-grazing and large scale monocultures on the Loess plateau in China have caused serious soil erosion by water and wind. Grassland revegetation has been reported as one of the most effective counter measures. Therefore, we investigated soil aggregation, aggregate stability and soil microbial activities as key parameters for soil remediation through grassland revegetation. The results showed that soil microbial biomass carbon (Cmic) and microbial biomass nitrogen (Nmic) increased under revegetated grass communities compared to cropland and overgrazed pastures and were higher in surface layers (0-10 cm) than in the subsurface (10-20 cm). Although there are variations between the four investigated grassland communities, their values were 10 to 50 times higher in comparison to the cropland and overgrazed pastures, similar to the increase in soil enzyme activities, such as '-Glucosidase and '-Glucosaminidase. Soil aggregate stability (SAS) showed clear differences between the different land uses with two main soil aggregate fractions measured by ultra sound: <63µm and 100-250 µm, with approximately 70% and 10% of the total soil volume respectively. We also found positive correlations between SAS and soil microbial parameters, such as Cmic, Nmic, and soil enzyme activities. From this, we concluded that revegetation of eroded soils by grasses accelerates soil rehabilitation.