| Populus euphratica oliv is one of the stress- tolerance and desert-grown species growing in saline arid and semi - arid areas. Their environmental benefits are windbreak, sand fixation,soil and riverbank protection, and water conservation to oasis,wildlife habitant as well as human settlements.From a global perspective, P.euphratica forests are strongly affected by human activities. As to our country, P.euphratica stands have been degraded due to the increase of the population and people's inappropriate use of water and land resources,cutting trees,the construction of water reservation and so on.Tarim Basin, in south Xinjiang, special geographical environment like this, if there is no P.euphratica ecosystem to maintain the ecological balance of the whole Tarim Basin, it is impossible for the oasis system to exist. Consequently it becomes difficulty for human beings to survive. Therefore, it has some research values for the protection and regeneration of P.euphratica natural stands, cultivation and fertilization for the artificial P.euphratica stands to analyses the quantities relationships between P.euphratica different growth status and it is environmental factors.In this paper, using Mapinfor GIS software and SPSS statistical software, combined with field research and laboratory analyses, adopted mathematical method, such as correlation, regression and principal component analyses, quantitive descript soil salinity, nutrient content,and groundwater characteristics of P.euphratica stands with different growth status. Considering P.euphratica foliage cover as the main reflective indicator of its growth status, tried to find out the quantitative correlations between the P.euphratica foliage cover and its main environmental factors. Research results showed that:1. Salt, groundwater characteristics of P.euphratica sampling plot with different growth status:Soil salt content appeared descending trend from the soil surface to deeper layer(0～1m); and the soil pH value appeared ascending trend from the soil surface to deeper layer(0～1m);Soil 0.3～0.5m,0.5～1m layer dried water content decrease from the P.eughratica sampling plot with good growth status to plot with withered status;No significant difference between soil organic matter content of P.euphatica with different growth status; and the soil 0～0.3m organic matter,total P, available P content higher then 0.3～0.5m﹑0.5～1m layer's ; Total K's distribution of soil different depth is uneven;No big differences between P.euphratica sampling plot's groundwater levels but have bigger differences between groundwater salt content.2. Correlation analyses of P.euphratica sampling plot's soil, groundwater characteristics:Soil conductivity with salt content,TDS,total P,available P,dried soil water content, soil organic mater with total K,dried soil water content, dried soil water content with soil available P,soil total K has a highly positive significant correlation (p<0.01);Soil conductivity with soil organic matter, soil organic matter with available P, soil available P with total P, total K has a higher positive significant correlation(p<0.05);Soil conductivity with soil pH value, soil pH value with soil available P has a negative significant correlation(p<0.05);3. Regression analysis between P.euphratica foliage cover and principal components:Inverse regression model between P.euphartica foliage cover and 0.5～1m soil salt content and with 0.3～0.5m soil pH value; logarithmic regression model with 0.5～1m soil conductivity and with TDS; linear﹑ quadratic﹑inverse,logarithmic,and cubic models between P.euphratica foliage cover and 0.5～1m soil pH value;Cubic regression model between P.euphratica foliage cover and 0～0.3m soil salinity; and logarithmic model with 0～0.3m soil available P and with 0.5～1m soil organic matter;Cubic regression model between P.euphratica foliage cover and groundwater level and Quadratic regression model with groundwater salinity;...
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