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题名	塔里木河下游植物群落物种多样性变化研究
作者	张宏锋
学位类别	硕士
答辩日期	2004
授予单位	中国科学院．中国科学院新疆生态与地理研究所．环境科学．
导师	陈亚宁，中国科学院新疆生态与地理研究所
关键词	塔里木河下游
其他题名	Study on the changes of species diversity of plant in lower reaches of Tarim River
中文摘要	塔里木河上游水土资源的大强度开发利用，致使塔里木河下游的大西海子水库以下320km河道断流30年。由于地表失去径流补给，地下水位大幅度下降，植被生长退化，生态系统受损。根据植被样地资料和地下水埋深观测资料，本文分析了塔里木河下游地下水位变化与物种多样性特征。在2000年实施塔里木河下游生态输水以前，塔里木河下游上段的英苏地区，地下水埋深达sm以下，下段依干不及麻地区下降到IOm以下。植被覆盖度由上段至下段呈明显降低趋势。塔里木河下游各断面的群落分布具有以下特征：（1）英苏和阿布达勒断面的群落类型为胡杨＋怪柳群落。在该群落的种类组成中，乔木主要是胡杨，灌木主要有多枝怪柳、刚毛怪柳、黑刺、铃铛刺，草本植物有甘草，罗布麻，骆驼刺、芦苇，另外还有数量较少的花花柴与猪毛菜。其中，胡杨与怪柳植物是该群落的优势种。从群落的垂直结构来看，可划分为乔木层、灌木层、草本层三个结构层次，但在不同断面，各层次在群落整体中的相对密度、相对盖度各不相同。而从群落的水平结构来看，群落内植株间生长稀疏，草本植物分布多呈碎片状，沿河道向下在种类、数量上呈减少、衰败态势。（2）喀尔达依，阿拉干、依干不及麻断面的群落类型为胡杨＋怪柳群落，群落的种类组成主要为胡杨与怪柳，还伴生有黑刺、少量铃铛刺。由于地下水埋深较深，草本植物稀少，除偶见深根系的骆驼刺外，几乎无其它草本植物，且植被多呈衰败状态，植被类型以荒漠化怪柳灌丛、怪柳灌丛、荒摸化胡杨林为主。在群落的水平结构上，整个群落呈现出复合性的分布特征，即以胡杨，胡杨+柽柳和怪柳三种类型组成形式，呈复合性分布。（3）依干不及麻和考干断面的群落类型为单一怪柳群落，该地区地下水位更低，植被严重退化，植被类型为荒摸化怪柳灌丛以及裸露的流动沙丘。（4）考干以下至台特玛湖已成了湖积盐土平原，地表植被无几。在对塔里木河下游断流河道实施4次生态输水后，河道两岸地下水位有一定幅度抬升。衰败的胡杨，怪柳群落呈现恢复态势脸临近河岸的低洼地带，生长出猪毛菜、河西芭、叉枝鸦葱等一些浅根系植物，而且长势很茂盛。从几次生态输水的效果来看，在河水发生漫溢的地段，草本植物种类增多，呈现出与远离河道地区截然不同的景观。根据塔里木河下游物种多样性与地下水埋深之间的灰色关联分析：在塔里木河下游，物种多样性与地下水埋深变化关系密切，shannon-Weiner指数、Simpson指数、Margalef指数、Menhinick指数、JSW指数和Jsi指数与地下水埋深之间的灰色综合关联度都在0.70以上，其中物种多样性指数SimPson指数与地下水埋深变化的灰色综合关联度最高，为0.866。其关联度数值体现了地下水埋深对物种多样性变化的主导性。改善塔里木河下游生态环境最根本途径就是提高该地区的地表植被覆盖度，从而遏止生态环境的恶化。从目前输水结果来看，现在实施的沿塔里木河原河道的线性输水，只能使那些根系较深的胡杨、柽柳等乔木和灌木达到复壮和生长，这对于增加地表植被覆盖度没有太显著的意义，也无法起到防风固沙的作用。比较有效的方式是通过一定的人工措施，有目的地实施面上输水，通过对种子库的激发，达到增加该地区物种种类，从而获得较大的生态效应。The intensive exploitation and utilization of water resources in upper researches of Tarim River led to cutting off of river from the Daxihaizi Reservoir to the Taitema Nor for 30 years. Without the supply of surface runoff, the groundwater table decreased continuously and vegetation degenerated. Based on the data of stationed plant plots and groundwater table in five sections in the lower reaches of the Tarim River, the character of groundwater table changes and species diversity are analyzed. Before the water conveyances to the lower researches, the depth of groundwater was below 8 meters at Yinsu section, below 10 meters at Yiganbujima section. The coverage decreased obviously from upper section to lower section. The distribution features of plant communities in sections of the lower researches of Tarim River are as follow: The community type of Yinsu section and Abudali section is Populus euphratica and Tamarix community. In the constitution of this community, arbor layer is composed of Populus euphratica; shrubbery layer is composed of Tamarix ramosissima, T. hispida, Lycium ruthenicum and Halimodendron halodendron; herbage layer is composed of Glycyrrhiza inflata, Apocynum venetum, Alhagi sparsifolia, Phragmites communis and a litter of Karelinia caspica and Salsola sp. Populus euphratica and Tamarix sp are dominant species among this community. At the angle of vertical structure of community, this community can be divided into arbor layer, shrubbery layer and herbage layer, but relative density and relative coverage of each layer among the whole community are different with each other. At the angle of horizontal structure of community, the distribution of plants is sparse and the distribution of herbage plants takes on fragmentation; the kinds and number of species decrease along from upper to lower at the lower researches of Tarim River. The community type of Kardayi section, Alagan section and Yiganbujima section is Populus euphratica and Tamarix community. This community is composed of Populu euphratica, Tamarix accompanied with Lycium ruthenicum and a little of Halimodendron halodendron. Because the depth of groundwater table too deep to be absorbed by the herbage with shallow root system, there hardly exist herbage except Alhagi sparsifolia with deep root system. Most plants take on degradation. The types of vegetation are mainly desert Tamarix scrub, Tamarix scrub and desert Populus euphratica forest. At the angle of horizontal structure of community, the whole community takes on compound distribution, i.e., the three types of Populus euphratica forest, Populus euphratica forest and Tamarix scrub and Tamarix scrub are combined together. The community type of Tiganbujima section and Kaogan section is sample Tamarix community. Here Vegetation is more degraded than the other regions for the deeper depth of groundwater table in this region. The vegetation types are desert Tamarix scrub and naked unstable dunes. The area from below Kaogan to Taitema Nor has become depositional saline plain, there is little vegetation here. After conducting ecological water conveyances to the lower researches for 4 times, the groundwater table near riverbed rises to some extent. The degraded Populus euphratica community and Tamarix community take on rehabilitation. At some washes near river, Salsola sp, Hexinia polydichotoma and Scorzonera sp grow and blossom. According to investigation of water conveyances of 4 times, the kinds of herbage species increase at the places where water has overflown, which take on a different landscape from the region away from river. According to the grey relationship matrix analysis between species diversity and depth of groundwater, there is- close relationship between species diversity and change of depth of groundwater in the lower reaches of the Tarim River: The integrated grey relation degrees between species diversity index including the Shannon-Weiner index, Simpson index, Margalef index, Menhinick index, JSW index and Jsi index are all above 0.70. The integrated grey relation degrees between Simpson index and groundwater level is highest among the species diversity index, which value is 0.866. The values of integrated grey relationship degrees between species diversity and change of groundwater level indicate that groundwater level is the dominant factor in the environmental factors which influenc the change of specie diversity. The ultimate avenue of ameliorating the ecological environment of the lower reaches of Tarim River is to increase the coverage of vegetation so as to prevent the environment from deterioration. In view of the result of water conveyances that are conducted along the old riverway in the lower reaches of Tarim River, which is a linear way of water conveyance, can only save Populus euphratica and Tamarix having deep root system. This way of water conveyances has not much significant effect on increasing vegetation coverage and fixing of sand. The efficient way of water conveyances is conducting transverse surface flooding to waken seed bank, which can increase the kinds of species and vegetation coverage for rehabilitating of ecological degraded region.
语种	中文
学科主题	生物多样性
公开日期	2010-11-12
页码	共48页
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/8384]
专题	新疆生态与地理研究所_中国科学院新疆生态与地理研究所(2010年以前数据)
推荐引用方式 GB/T 7714	张宏锋　. 塔里木河下游植物群落物种多样性变化研究[D]. 中国科学院．中国科学院新疆生态与地理研究所．环境科学．. 2004.

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