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沙质草地沙漠化过程中土壤动物群落结构变化是沙漠化生物过程中的一个重要方面,对于掌握沙漠化过程中生物退化规律和提出合理沙漠化防治对策具有重要指导作用。选取处于不同沙漠化阶段的流动沙地、半流动沙地、半固定沙地、固定沙地和丘间低地5种生境类型,采用手拣法对其大型土壤动物群落进行了调查。共获得36个动物类群,属于8目32科,优势类群为蚁科,常见类群有22个类群,两个类群的个体数共占群落个体总数的93.33%;稀有类群有13个类群,其个体数占群落个体总数的6.67%。结果显示,丘间低地、固定沙地、半固定沙地和半流动沙地大型土壤动物群落个体数量、类群数和多样性显著高于流动沙地(P<0.05);固定沙地大型土壤动物生物量显著高于其它生境类型(P<0.05);沙质草地严重沙漠化显著地影响大型土壤动物多样性及其生物量。并且,不同土壤动物类群个体对不同沙漠化阶段生境的适应性存在一定差异,产生了不同的响应模式。土壤有机碳和酸碱度以及土壤含水量差异是影响大型土壤动物类群分布与生长的主要因素。研究表明,固定沙地是大型土壤动物的适宜沙地生境,具有较多的个体数量和较高的生物量;丘间低地、半固定沙地、半固定沙地和流动沙地影响大型土壤动物存活,其个体数量和生物量较低。
The change of soil animal community structure during sandy desertification is an important aspect of biological processes of desertification, which plays an important guiding role in grasping the law of biological degradation in desertification and proposing the countermeasures of rational desertification. Five habitat types of mobile sandy land, semi-mobile sandy land, semi-fixed sandy land, fixed sandy land and low lying hill land in different stages of desertification were selected and their macrofauna community was investigated by hand picking method. A total of 36 animal groups were found, belonging to 8 orders and 32 families. The dominant groups were the families of ant families. There were 22 common groups, of which the individuals accounted for 93.33% of the total. The rare groups had 13 groups, The number accounted for 6.67% of the total number of community individuals. The results showed that the number of individuals, the number of groups and the diversity of macro soil fauna community in lowland, fixed sandy land, semi-fixed sandy land and semi-floating sandy land were significantly higher than those in sandy sandy land (P <0.05) Biomass was significantly higher than other habitat types (P <0.05). Severe desertification of sandy grassland significantly affected the diversity and biomass of macro-fauna. In addition, there were some differences in adaptability of different soil fauna groups to habitats at different desertification stages, resulting in different response patterns. Soil organic carbon and pH, as well as differences in soil water content, are the major factors affecting the distribution and growth of large soil fauna. Studies have shown that fixed sandy land is a suitable sandy habitat for large-scale soil animals, with more individuals and higher biomass; low-lying mound, semi-fixed sandy land, semi-fixed sandy land and mobile sandy land affect large soil animals Survival, its individual number and biomass are low.