莫索湾绿洲的建立与梭梭荒漠的动态研究

本文就古尔班通古特沙漠南缘的梭梭荒漠、在本世纪５０年代后期开发以来发生的变化，分析绿洲形成过程、依存条件及其与荒漠关系，并对绿洲界外区的生态地位、发生原因和其对策进行剖析。

STUDIES ON ESTABLISHMENT OF MOSOUWAN OASIS AND THE VARIATION OF SACSAOUL DESERT

Mosouwan Oasis was established since the late 1950’s,This peninsula─shaped Oasisstretchs 60km from the south of the basin into the deep desert.Before exploited theSacsuoul kept dominance in the desert vegetation。The average cover degree of vegetationwas about 30%。Of all the basin,95% was fixed duns.In this area,annual precipitation was117mm。In winter,the snow deposit was about 25─30mm,The snow water in springprovided the bases for anabiosis of the desert vegetation and the rampancy of ephemeralplant。Since Mosouwan Oasis was exploited on Iarge scale in the July of 1958,the relativeuniform landscape has turned into three different types,that is booming Oasis,degeneratedarea around the oasis and primitive desert.They arrange as circular layer in the space,Oasis lies in the centre,then the area around the oasis and undisturbed desert. The research has showed that:such intense differentiation in the limited space and time,must be caused by human activities rather than climate。People drew water into oasis and replaced protophytes with forest zone and farmland。By this way, vegetation structure,primary productivity and environmental qual0ity are all in the ascendant on Oasis。The outslde of oasis has been disturbed but nobody remake it,so the ecosystems apparently degenerate。 Because the action strength gradually decreases from near to far,the area aside Oasis was destroyed,and about(40─60 km from Oasis),the effects disappear,so the former is named the area around the Oasis,and the later is still desert。Now we find out grgzing and cutting are the main reasons disturbing the outside area,but their actions range and effect are differrent.The grazing is mainly in spring, but the desert lack of drinking water,so the grazing districts are limited in 0─10 km away oasis,the herb layer coverage and composition changed.Grazing and cutting have an effect onshurb at the same time,their action spread all over the area around the Oasis but decreasesfrom near to far。Cutting declines shrub density and leads the proportion of young tree inthe ascendant.Grazing shortens height of plants。If we want to change the serious problems caused by exploiting.The first thing is toreestablish the vegetation on the area around the Oasis.The reasearch shows that:this areais lack water resource,we can't use the conventional way to build forest.We should depondon the natural coenosium rules and natural resources to reestablish the vegetation of the alea.