纳帕海退化湿地土壤有机质空间变异研究

Study on the Spatial Variability of Soil Organic Matter in Napahai Degraded Wetland

对云南省西北高原纳帕海湿地生态系统受不同强度人为活动干扰的土壤有机质空间分布状况进行研究,通过统计学特征值和土壤退化指数分析,结果表明:纳帕海湿地土壤有机质含量的水平空间分异为沼泽>沼泽化草甸>垦后湿地>草甸,变异程度为44.68%,垂直空间分异上差异显著,表层土壤有机质含量高于亚表层,变异程度沼泽化草甸63.32%,草甸54.95%,垦后湿地49.93%,土壤退化指数定量反映了不同强度人为干扰下湿地土壤有机质的退化程度,即原生沼泽随人为活动干扰强度加剧而退化程度加深.

This paper has mainly analyzed the spatial distribution of soil organic matter(SOM)under different human disturbances in Napahai wetland ecosystem, northwestern Yannan Plateau. Based on analyzing the statistical characteristics of SOM and soil degradation index(SDI), the following results were obtained: the horizontal variation of SOM content from four types of land utilization in Napahai wetland ecosystem is marsh>swamp meadow>reclaimed wetland>meadow, the coefficient of variation(C.V.) was 44.68%; and the vertical variation was obvious, i.e. the SOM contents of swamp meadow, meadow and reclaimed wetland in 0～20 cm layer was higher than those in 20～40 cm layer, the C.V.% was 63.32%, 54.95% and 49.93%,respectively. It was proved that SDI could be a quantitative index to show the degraded degree of wetland SOM under different human disturbances. It was showed that Napahai wetland had been deteriorating by human beings, the more intensive disturbance, the more serious degradation. 