【作者】 张琳；

【导师】 杨劼；

【作者基本信息】 内蒙古大学 ， 生态学， 2011， 硕士

【摘要】 柳湾林是毛乌素沙地特有的景观类型,主要分布在毛乌素沙地丘间低地及滩地边缘,由乌柳(Salix chcilophila)、中国沙棘(Hippophoe rhamnoides)、沙柳(Salix psammophila)和林下草本共同构成的植被类型。同时,它具有维持生物多样性、防风固沙、调节气候、提供天然产品等多种功能。但是,在过去的几十年里,由于柳湾林面积减少,对沙区的生态环境及当地牧民的生产生活产生重要影响。因此,本文对柳湾林植物区系、群落分布格局及其动态变化几方面进行了分析,研究结果如下：1.柳湾林共采集到34科98属132种植物,其中生活型以多年生为主,水分生态类型以中生为主,区系成分温带成分占比例最高。2.柳湾林群落分布格局呈明显的带状分布,并且水分和土壤机械组成是影响柳湾林群落分布格局的主要影响因素。随着水位的下降,草本群落多样性指数、地上生物量和土壤有机质含量均呈下降的趋势。3.从1986年到2007年研究区的柳湾林面积减少了421.57km2,其中,192.57km2的柳湾林转化为盐碱化低地。这是研究区气候变化和人类活动共同作用的结果,1986年到2007年之间研究区年平均气温呈升高的趋势,而生长季的降暑量呈下降的趋势,柳湾林得不到充足的降水补给；柳湾林周围因农田开垦或林业种植而改变柳湾林水文条件,最终导致柳湾林生境干旱化。更多还原

【Abstract】 Liu Wanlin, an unique landscape of Mu Us desert, is mainly distributed in lowland and the edge of bottomland. There are Salix chcilophila,Hippophoe rhamnoides, Salix psammophila and undergrowth herb which constitute vegetation types.Meanwhile, Liu Wanlin bears a function of maintaining biodiversity, wind prevention and sand-fixation, regulation climatic and providing natural products and so on. But,in the past few decades, the area of Liu Wanlin reduced which exerts an important influence on the ecological environment and the living and production of Nomads. So the author of the thesis studies on flora, distribution pattern and dynamic change of Liu Wanlin. The result are as follows:1. There are 34 families 98 genera 132 species, the most important life style is perennial plant,moistrur ecotype is mesophyte and temperate plant.2. It is temperate clear zonal distributing and moisture and mechanical composition is the important factor for Distribution pattern of Liu Wanlin With the water level falling, herb community diversity index, aboveground biomass and soil organic matter content will show a downward trend. 3. From 1986 to 2007, the Liu Wanlin study area was reduced by 421.57km2. In this study area,192.57 km2 of Liu Wanlin transfered into saline lowlands. This is caused by the climate change and human activities. From 1986 to 2007, the average temperature in the study area showed an increasing trend, while the growing season’s downward in summer showed a reducing trend.There is no enough rainfall in Liu Wanlin.Consequently, reclaiming farmland and planting around Liu Wanlin changed its hydrological conditions, resulting in habitat drought in Liu Wanlin.KEYWORD:Mu Us;Liu Wanlin;Dynamic changes更多还原