The Relationship Between Growth Indicators And Rhizoshpere Micro Environment Of Ulmus Pumila In Hunshandake Sandland

It's extremely urgent to control desertification on account of serious desertization problem in Hunshandaka sand land has restricted the sustainable development of local ecology,economy and social environment.Ulmus pumila is not only the main arbor species but the only Ulmaceae Ulmus arbor,which makes great difference to maintain stability and restore ecology.At present,the research on ecological characteristics of Ulmus pumila has been reported.However,it has not been studied from soil microorganism and enzyme activity,especially from rhizosphere microdomain environment,which is closely related to the growth of Ulmus pumila.In this paper,we take the trees' growth indications to conductsampling analysis firstly and examine the rhizosphere soil as a research object.By locatingthe sampling area in three geographic regions: eastern Hexigten Banner,mid Plain Blue Banner and western Plain and Bordered White Banner,we select three different site types are for comparative study and choose actual rhizosphere soil samples to cultivate and measure in each site type for analyzing the relativity of the soil nutrition content.Combining path analysis,we research on the relationship of Ulmus pumila among the growth status,rhizosphere soil nutrients,microorganism and enzymatic activity in Hunshandaka sand land.The results showed:(1)From east to westthe various growth indicators are higher and higher.The growth indexes of the inter-dunes and shady-slopesare higher than that of the south-facing slopes.The rhizosphere soil micro environment are consistent with the growth indexes.(2)In the three major soil microorganism,the quantity of them varies greatly from the others.The number of bacteria is the largest,followed by actinomycete and fungus.The growth of microbial population is secret relationship to nutrient competition.The activity of four kinds of soil enzymatic is also different in quantity,which is the largest sucrase,the next phosphatase and urease,the least catalase.The enhancement of enzyme activity promoted the release of soil nutrients,The comprehensive fertility of soil is higher in sand.(3)We draw the conclusion that the branch diameter is influenced most greatly onthe rhizosphere soil nutrients,microorganism quantity and enzymatic activitybased on the analysis of the correlation between the growth indexes of the Ulmus pumila and the underground microorganism.(4)There is significant association among rhizosphere soil nutrients,microorganism quantity and enzymatic activity showing that they are interaction,interplay and promote soil nutrient cycle collectively.It can be used as an evaluation index to evaluate soil fertility.(5)On the basis of simple correlation analysis,By the analyzing of soil nutrients,the amount of soil microorganism and soil enzymatic activity,The organic matter and the available phosphorus have direct effects on them,The results showed that they provided abundant nutrients and enzymatic reaction substrate.