The Response Of Plant And Soil To Different Plant Functional Groups Loss In Alpine Meadow

In this experiment, alpine meadow on the eastern Qinghai Tibet plateau naturalmeadow as the research object, through the manual removal of different plant functionalgroups of simulation of plant diversity loss, with nitrogen simulation of atmosphericnitrogen deposition, measurement and analysis of vegetation coverage, abovegroundbiomass and species richness of plant communities in3on the index; soil organic matter,available nitrogen in soil, soil moisture, soil pH of4soil physical and chemical properties;soil nematode, soil bacterial diversity index of2indicators. Study on plant and soilecological system in the short term the plant functional group loss of response, in order torational utilization of grassland in alpine meadow and protection management to providesome theoretical guidance; at the same time, the biological diversity of Alpine MeadowDegradation of ecosystem function reconstruction and restoration of degraded grasslandto provide certain theoretical basis for the protection, promotion.The main conclusions are as follows:(1)After the loss of plant functional group, plant communities in alpine meadowvegetation coverage, species richness and biomass were affected in different degree andreduce. Compared to other removal processing plant functional groups, the removal ofnon grass community aboveground vegetation part of each index were the lowest,indicating that non grasses are dominant plant functional groups, have a significant impacton the alpine meadow plant diversity and productivity.(2)The loss of different plant functional groups has no significant effect on soil organicmatter, soil moisture, soil pH, but the available N especially the nitrate nitrogensignificant influence, description the plant functional group are niche differentiation, butalso shows the loss of different plant functional soil on short-term group have a certainresistance,or different plant functional soil on short-term group loss response may exist acertain time lag. In addition also showed that fertilization stage gramineous plants onnitrate uptake and utilization is higher than other plants; fertilization of late nonGramineae dominant.(3)The loss of diversity of short-term plants has a significant effect on soil nematodes and soil bacterial diversity in alpine meadow area.Especially the removal of gramineousfunctional group, number of soil nematode and bacterial diversity were the least,explainthat gramineous functional group is the key functional groups in the Plant functionalgroup in alpine meadow area.(4)The correlation analysis showed that: above ground biomass, vegetation coverage,species richness and soil ammonium nitrogen content had significant positive correlation(P <0.05) and highly significant positive correlation (P <0.01); the ground biomass andthe number of soil nematodes were positively correlated (P <0.05).The results showedthat the plant functional group loss indirectly affect the soil available nitrogen contentthrough the direct impact of the characteristics of plant community.At the same time, thecontent of available nitrogen in soil dominant control of characteristics of plantcommunities.The content of organic matter and nitrate nitrogen in soil directly influencethe number of soil nematodes,At the same time, soil nematode effects of soil fertility andsoil productivity by taking part in the decomposition of organic matter and nitrogenmineralization.