Study On Plant Diversity And Soil-plant Nutrients Spatial Variability In Small Scale In Yunwu Mountain Grassland

Yunwu Mountain grassland is typical semiarid grassland in Loess plateau and it is a typical example in plant recovered. In this paper applying inner analysis and field research to study small scale plant nutrients distribution, plant diversity, 0-20cm layer and 20-40cm layer soil nutrients distribution, the relationship between soil nutrients and plant community characters in this area; The classical statistics method and geostatistics method combined to analyze the spatial variability of soil nutrients and moisture. The main conclusions are as follows:1. In sample area, there are 20 familia, 37 genus and 50 different species. The important value of Tieganhao is the highest(33.87%), and next is Changmangcao( 29.12%) , As dominant species, they forms grassland plant community in this area; 43 species patter distribution are clumped and 7 scale species are random.2. The result shows, species and numbers of unities present normal distribution, but biomass presents logarithm normal distribution; Plant water content and total N content present normal distribution, P content,K content,P accumulation and K accumulation present logarithm normal distribution, but N accumulation is not normal or logarithm normal. The research results are advance and supplementary to plant nutrients content and nutrients accumulation that dealt with normal distribution before.3. The correlation analyses between different diversity indexes shows, Species richness indexes and Species evenness indexes have not correlation, Species richness indexes and species diversity indexes presents correlation, Shannon-Wiener index and Species richness indexes have a great significant correlation, Species evenness indexes and Species diversity indexes presents a significant correlation, Simpson index have a significant correlation with Species evenness indexes.4. The analyses about the distribution patter of soil nutrients and moisture in two soil layers (0-20cm and 20-40cm) shows, 20-40cm soil layer total N and 0-20cm soil layer NH₄⁺ -N are not normal or logarithm normal distribution, the contents of NO₃^- -N presents logarithm normal distribution in two different soil layers, 0-20cm layer A.P presents logarithm normal distribution, the rest nutrients and soil moisture presents normal distribution, the...