Study On Landscape Pattern And Soil Hydrological Characteristics Of Populus Euphratica Forest In Middle Reaches Of The Tarim River

The middle reaches Populus euphratica forest region is one of the important national protected areas,this study applied remote sensing and analysis techniques, combined with field survey method onlandscape scale, and in-depth explored temporal and spatial variation characteristics of regional landscapepattern, while firmly grasped the important aspect of soil hydrological characteristics of influence area thispopulus landscape pattern change, discussed the relationship of hydrological spatial distributioncharacteristics and typical landscape patch, studying, through the study got the following conclusions:(1) All kinds of land use patch has undergone significant changes in1993to2014, which patches offarmland from scratch, in landscape area gradually expanded, rapid growth, and populus forest patchesdecreased significantly. During the time shrub patches continually increased, which reflects the wholeregion dominated by populus forest communities at last, now was dominated by shrub communities, ofwhich was gradated desert shrub community. At the same time, populus forest landscape patches showedcharacteristic fragmentation and landscape gradually disappearing.(2) Desertification landscape changed significantly in1992to2009, slight sandy desertification areawere in dominant position in1992, but until2009, very severe desertification area has risen to the first,reflecting the trend of desertification was became very serious.(3) The impact regional range by the hydrological gradually narrowed in1992to2009. It was thewidest range period of hydrological impact in1992, and the space distribution in the landscape was moreuniform, but most of the area belonged to the range of severe water shortages in2009, some are of mildshortages gradually narrowed, and concentrated near the rivers, and a large area of water has actuallydisappeared.(4) Populus forest river water network has undergone significant changes in1992to2009, the spatialdistribution of hydrological network was more intensive in1992, can be extended to most of the region andthe space, but river was gradually shorter in2009, part of area river network disappeared and spatialdistance increased. It showed the area effected by network was gradually reduced.(5) Studies have shown that differences were more obvious in hydrological and physical properties ofsoil in different landscape patches regional, in riparian zone1meter deep soil layer, the average moisturecontent were lower as the distance from the banks to far more, showed a downward trend, and reflect theimpact of river water dropped. The coefficient of variation of soil was difference more obvious, andshowed downward trend, which led to the differentiation of vegetation, tree roots more deeply located in aregion near the river bank, and drought tolerant shrubs and herbaceous plants were more tend to be locatedin the transition zone and the desert landscape patches in the area. In the soil hydrological and physicalproperties, soil moisture content has a significant positive correlation with the coverage of trees, shrubs andherbaceous and with the shrubs frequency. At the same time the degree of soil aeration could reflectdrainage conditions, and their impact on Populous was more significant. This was consistent with featuresof populus landscape patches were located in the surrounding area of the river water network.