Astudy On Above-ground Biomass Of Tughai Forests In Middle Reaches Of The Tarim River

The thesis selects the Tarim Populus euphraticas Nature Reserve,which located in Middle Reaches of the Tarim River.It is a biggest Populus euphratica Nature Reserve in china. This Nature Reserve Plays an important roal the keep the ecological balance of Tarim River area . P.euphratica(Populus euphratica),at Tarim Nature Reserve,growing in their natural habitat represents a valuable resource for elucidating mechanism of acclimation to environmental constraints.P.euphratica is a salt-tolerant tree species growing in saline semi—arid areas.It is one of the stress—exposed and desert—grown species.Therefore,the P.euphratica has been treated as main protecting object and the Tarim Nature Reserve is one of two P.euphratica Reserves in China.Also plays great significant role in maintaining the ecological balance of the Tarim basin. However,the P.euphratica nature reserve eco—environment is getting more and more degenerate- due to the human activities in recent years.This paper analyzes the ecological frangible factors and their influence mechanisms on the nature reserve eco—system stability using 3S technologies.The results showed the eco—environmental condition of P.euphratica is fragile and the ability of insisting on the artificial influence is weak because of the harsh climate conditions,and human irrational water use and land resources.The shortage and exhaustion of surface water,as well as desdance of groundwater depth , make populus euphratica forests deteriorating.The protecting strategies are suggested in this paper according to the research analysis.This thesis selected Poplar nature reserve in middle reaches of Tarim in Xinjiang as research area, based on field investigation, combining statistical analysis and related ecological knowledge, using PCQ method to measure and analyze above ground biomass of poplar forest in middle reaches of Tarim river which offered scientific base and reference on ecological environment and protection and revitalization of Poplar forest that is to improve fragile desert Tarim ecosystem。Study result shows: 1)Morphological variables of Poplar forest in the study area and distance from river course has significant correlation. As distance widens from sample site to river, DBH, crown and age reveals a rule how they interact.。2)Amount of above ground biomass of Poplar tree and distance from river course has strong correlation. The forest distributed near the river course has higher density and quantity and well grown and its biomass from branches and leaves are bigger correspondingly. As distance further from river course, it displays lower density and quantity with old and dead trees as main types, its biomass from trunk and roots are bigger correspondingly...