【摘 要】
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In semi-arid areas of China,gravel and sand mulch is a farming technique with a long history.In this study,a sample sur-vey was conducted on long term gravel sand mulch observational fields in the Northwest Loess Plateau to determine the effects of long t
【机 构】
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Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou,Gansu 73000
论文部分内容阅读
In semi-arid areas of China,gravel and sand mulch is a farming technique with a long history.In this study,a sample sur-vey was conducted on long term gravel sand mulch observational fields in the Northwest Loess Plateau to determine the effects of long term mulch on soil microbial and soil enzyme activities.We found that after long term gravel-sand mulch,compared with bare ground,soil organic matter,alkali nitrogen,conductivity decreased,while pH and soil moisture in-creased.Urease,saccharase and catalase decreased with increased mulch thickness,while alkaline phosphatase was re-versed.The results of Illumina MiSeq sequencing shows that after gravel-sand mulch,the bacterial and fungal community structure was different from bare land,and the diversity was reduced.Compared with bare land,the bacteria Proteobacte-ria and Acidobacteria abundance increased with increased thickness,and Actinobacteria was opposite.Also,at the fungal genus level,Fusarium abundance was significantly reduced,and Remersonia was significantly increased,compared with bare land.Redundancy analysis(RDA)revealed that soil environmental factors were important drivers of bacterial com-munity changes.Overall,this study revealed some of the reasons for soil degradation after long term gravel-sand mulch.Therefore,it is recommended that the addition of exogenous soil nutrients after long term gravel-sand can help improve soil quality.
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