【作者】 朱振华；

【导师】 汪季； 董建林；

【作者基本信息】 内蒙古农业大学 ， 水土保持与荒漠化防治， 2008， 硕士

【摘要】 通过对乌审旗毛乌素沙地不同飞播年限的植被和土壤进行实地调查,并结合4期的遥感影像图,分别从时间、空间序列分析了飞播后植被群落景观格局的动态变化、植被的演替过程和土壤理化性质的变化。研究结果如下:(1)从4期遥感影像图来看,不同时期景观要素的类型和面积大小各不相同,而景观要素类型的不同则反映出在不同演替阶段的植被特征。本文采用平均斑块面积、景观分离度和斑块伸长指数这三项景观指数来分析不同时期植物群落的动态变化,并运用归一化植被指数NDVI评价4期影像中植被的覆盖度,并由此得出了沙地从流动状态到半固定和固定状态的转变。(2)毛乌素沙地飞播植物群落的演替过程可分为3个阶段。第一阶段为先锋阶段,植被表现为籽蒿+羊柴群落;第二阶段为过渡阶段,植被表现为羊柴+油蒿群落;第三阶段植被表现为羊柴群落。人为干扰在一定程度上决定着羊柴群落的演替,合理放牧和经营管理可使羊柴群落处于相对稳定的阶段。(3)飞播以后植物群落自身引起的群落环境的改变主要表现在地表0-10cm深度内土壤粉粒含量、有机质含量、全氮含量和全磷含量的增加,而沙地土壤的这些理化性质的变化又正是群落进展演替的动力。(4)从植物群落变量和土壤的理化性质之间的相关性来看,羊柴盖度和土壤的有机质含量、全氮含量呈正相关(p<0.05)。更多还原

【Abstract】 Through the field suvery of vegetation and soil different years aerial seeding in Mu Us sandy Land, and in conjunction with four remote sensing images, analysis vegetative landscape pattern change from time series, the succession of vegetation and Physical and chemical characteristics of sandy soil from space sequence analyse. The main results are as follows:1. From four remote sensing images, the areas and types of landscape elements are different with the different times, different types of landscape elements reflect different stages of vegetation succession, and from the average plaque area, the landscape isolation and elongation index to reflect the landscape at different times of dynamic change plant communities, and using Normalized Difference Vegetation Index rating vegetation coverage in four images, and obtained that from the flow of sand to the state of semi-fixed and fixed in the process of change.2. Succession of the aerial seeding vegetation in the Mu Us Sandy Land can be divided into three stages, the first stage is the pioneering stage (Form Artimisia sphaerocephala+Hedysarum leave),The second is the transitional stage (Form H. leave+A. ordosicaor),the third stage is the stable stage (Form H. leave).human disturbance determine the community succession on certain degree. Reasonable grazing and management can make H. leave community stable. 3. Studies show that the community environment changes after aerial seeding in Mu Us Sandy Land mainly infulent the increase of content of soil silt particle,organic matter,total nitrogen and total phosphorus in 0-10cm depth.All these changes are that the power of the vegetation community succession.4. From the correlation coefficients between the soil content and vegetation community variances, H. leave community and content of soil organic matter and total nitrogen were significant positive correlation (p<0.05).更多还原