呼伦贝尔草原沙漠化对土壤碳氮磷及化学计量的影响OA

[Objective]To elucidate the impact of desertification on the carbon,nitrogen,and phosphorus(C,N,P)content and their stoichiometric characteristics in the soil of the Hulunbuir grassland,providing theoretical refer-ences and data support for the management and restoration of desertified areas in the Hulunbuir grassland.[Method]Soil samples were collected from depths of 0-10 cm and 10-20 cm in areas with varying degrees of desertification.One-way ANOVA,principal component analysis,and Pearson correlation analysis were employed to explore the changes in soil C,N,P content and stoichiometric ratios,and their relationships with soil physical and chemical proper-ties in different desertification zones.[Result]1)With increasing desertification,the overall content of soil C,N,and P and their stoichiometric ratios showed a decreasing trend,with the loss rates of soil C,N,and P content being in the order of C>N>P.The content of fine and medium soil particles also showed a decreasing trend,while the content of coarse particles increased significantly.However,changes in soil moisture content and the soil carbon-clay ratio were not significant.2)The soil pH value generally decreased with increasing desertification,but showed a slight in-crease in areas with very severe desertification.3)Except for pH,changes in soil C,N,P content,stoichiometric ra-tios,particle size,moisture content,and soil carbon-clay ratio were not significant between different soil layers.4)During desertification,changes in soil pH and medium particle size were the main driving factors affecting soil C,N,and P content,while changes in soil moisture content were secondary driving factors.[Conclusion]Desertification sig-nificantly affects the content and stoichiometric characteristics of soil C,N,and P.Compared with non-desertified land,desertified land shows a decreasing trend in soil C,N,and P content and stoichiometric ratios,primarily due to the reduction in fine and medium soil particles caused by desertification.However,desertification has no significant impact on soil moisture content and the carbon-clay ratio,but significantly affects soil pH.