Vertical changes of soil microbial properties in claypan soils
Autor: | Che-Jen Hsiao, Ganga M. Hettiarachchi, Lydia H. Zeglin, Charles W. Rice, Gretchen F. Sassenrath |
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Rok vydání: | 2018 |
Předmět: |
0301 basic medicine
Phosphorus Soil Science chemistry.chemical_element Biomass 04 agricultural and veterinary sciences Soil carbon complex mixtures Microbiology Claypan Soil management 03 medical and health sciences 030104 developmental biology Agronomy chemistry Soil water 040103 agronomy & agriculture 0401 agriculture forestry and fisheries Soil horizon Subsoil |
Zdroj: | Soil Biology and Biochemistry. 121:154-164 |
ISSN: | 0038-0717 |
Popis: | Microbial activity within the soil is critical for plant growth and development, and a major determinant of crop performance and yield. Claypan soils are characterized by a dense, impermeable subsoil that impedes root system development. Little is known about soil microbial properties in claypan soils or how microbial activity changes with depth in the soil profile. We explored how management practices mediate changes in soil microbial composition and potential enzyme activities with depth in a claypan soil. The soil microbial biomass and composition were examined through phospholipid fatty acid (PLFA) assay. We found that the soil organic carbon (SOC), microbial biomass, and oxidative enzyme activities declined with depth, while hydrolase activity increased in the upper layer of the claypan. Changes in soil management practices affected the degree of increase in hydrolase activity in subsoils, especially for N-acetyl-β- d -glucosaminidase. No accumulation of SOC in the claypan layer was observed. Contrary to our expectation, soil microbes deeper within the soil profile were phosphorus- and nitrogen-limited rather than carbon-limited. Vertical stratification of measured soil properties was found with an upper layer from 0 to 15 cm, an intermediate layer between 15 cm and approximately 30 cm, and the lowest layer of soils in the claypan below 30 cm. The interaction between clay content and changes in soil factors with depth resulted in an increased potential activity but unaltered microbial composition in the claypan layer. |
Databáze: | OpenAIRE |
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