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题名	塔里木河下游生态输水过程中指被变化的遥感研究
作者	段含明
学位类别	硕士
答辩日期	2008
授予单位	中国科学院．新疆生态与地理研究所
导师	艾里西尔·库尔班，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 Vegetation Change by Remote Sensing During Ecological Water Transfusion in the Lower Reaches of Tarim River
中文摘要	由荒漠河岸林构成的塔里木河下游绿色走廊，自20世纪中期以来逐渐衰败。1972年大西海子水库建成，其下游河道断流，加剧了绿色走廊的缩减，分布于塔里木河两岸的塔克拉玛干和库鲁克两大沙漠有合拢之势。为挽救沿岸植被，恢复受损生态系统，抑制沙漠化，中国政府批准投资107亿元人民币对塔里木河进行综合治理；并于2000 年开始实施由大西海子水库向断流30年的塔里木河下游河道输水的应急输水工程。截至2007年年底，先后共完成了九次生态输水，使沿河地下水位得到了抬升，并沿岸植被发生了相应变化。 本研究以2000年开始实施的生态输水为背景，选取垂直输水主河道中心线，向两岸12km范围作为研究靶区，利用多时相遥感数据，研究了塔里木河下游两岸自然植被对生态输水的响应过程和变化趋势。 1．利用2000~2005年逐年的CBERS/CCD数据，采用时间轨迹分析法，研究了土地覆被在植被与非植被之间的变化过程和趋势。首先根据各年的SAVI直，进行了植被和非植被类型的分类，从而建立了6年的植被/非植被类型序列图；根据6年的序列图，构建了每一个像元6年的变化轨迹；并根据变化过程特征和变化趋势把变化轨迹归纳为恒定非植被、恒定植被、转变为植被、转变为非植被、非稳定变化等5种变化类型；分析了5种变化类型的空间分布特征。 2．采集了9个典型断面的MODIS植被指数时间序列数据，并根据植被指数的年内和年际变化特征，结合地面调查，分析了各断面植被状况的变化趋势。 3．遥感数据分析结果，与生态输水及监测资料和地面调查资料相结合，分析了植被变化的过程、趋势、发生变化区域的植被结构与生态输水量、输水时间和输水方式的关系。并对生态输水方案的优化提出了建议。 论文的主要结论如下： (1) 生态输水过程中，植被面积逐年扩大，植被长势逐年好转。2005年比2000年净增植被面积150.27 km2。植被面积的最高值出现在2004年，最低值出现在2001年。表明生态输水对植被面积的增加和长势的好转起到了重要的作用。 (2) 各年植被面积与其前一年的生态输水累积量呈显著正相关。前者随后者的增加而增加；同时植被面积的增加对生态输水的响应有一年的滞后期。 (3) 在生态输水过程中，转变为植被与转变为非植被两种变化趋势并存。 转变为植被的变化类型占优势。表明生态输水已经起到了维持现有植被面积的作用。转变为植被的优势地位与植被面积逐渐扩大趋势相吻合。 (4) 转变为植被的像元主要是在2004、2005年才表现为植被像元，这在河水漫溢、滞留区域最为明显。这种变化主要与生态输水后以芦苇为主的草本植被恢复和衰败的红柳灌丛复苏有关，表明河水漫溢有助于局部草本植物和灌木植被的面状恢复。乔木林（胡杨林）在面积上没有明显的增加，但是郁闭度和长势得到了明显的改善。 根据以上结论，主要提出了以下建议：持续进行生态输水；并在输水方案的制定过程中，在确保恒定植被的前提下，优先考虑扩大和保护转变为植被的区域，并尽可能的争取将非稳定变化区域转变为稳定地植被，促进植被面积的进一步扩大。The ‘Green Corridor’ ebbed constantly from 1950s；Construction of the Daxihaizi Reservoir in 1972 disrupted much of the stream-?ow in the Tarim River, resulted in large decrease of vegetation area. The Taklamakan and the Kuruk deserts like to get together if the decreasing trends of vegetation area couldn’t be stopped. So, an emergency project conveying water to the lower reaches of Tarim River was implemented from 2000. The ecological water transfusion had carried out for 9 times from 2000 to 2007. The ground water conditions have changed obvious along the dried-up watercourse; accordingly, the riparian vegetation shows improvement to a certain degree. This research is based on the ecological water transfusion, and the region within the distance of 12km from the river was selected as the research region. We used multi-Temporal remote sensing data to reveal the change processes and trends of natural vegetation responding to ecological water transfusion. 1. The change processes and trends of land cover converting between vegetation and non-vegetation were revealed, based on temporal trajectory analysis using multi-temporal CBERS/CCD images from 2000 to 2005. At first, the land cover was classified into two classes: vegetation and non-vegetation according to the threshold of SAVI. Then the change trajectory of every pixel was constructed through image calculation between previous classification maps. Based on the change trends, all trajectories were characterized into five trends groups: stable non-vegetation, stable vegetation, change into vegetation, change into non-vegetation and unstable change class. The change trajectories express the change processes of pixels, and reveal the expansion or reduction of the regional vegetation. 2. We collected the time serial data of MODIS indexes of 9 representative sections along with the watercourse. Through analyzing intra-and inter-annual change processes of vegetation indexes, the change trend of vegetation cover condition in every section was assessed. 3. Integrating the results of remote sensing analysis with datum of ground surveys and water transfusion, we tried to discover the plants components of different change classes, and the relation between vegetation change and water transfusion. The main conclusions we got are listed as following: （1） During ecological water transfusion, the overall vegetation areas increase continually and the vegetation condition improved at the same time. The net increment is 150.27km2 from 2000 to 2005. The minimum of vegetation area is of 2001; and the maximum one is of 2004. It means that water transfusion accelerated the vegetation improvement. （2） There is a significant correlation between vegetation area of every year and the accumulative total of transfused water in the last year. The farmer increased according as the latter’s increase, and there was one year delay of vegetation area expansion. （3） The two trends of ‘change into vegetation’ and ‘change into non-vegetation’, which are mutual boycott, exist at the same time. The preponderant one decide the main change direction. Between 2000 and 2005, ‘change into vegetation’ is preponderant; and the basic aim to maintain the existing vegetation has carried out. （4） The pixels which trends are ‘change into vegetation’ converted to vegetation mainly in 2004 and 2005. These cases are particular obvious in some cluster regions, where water flooded and temporary lakes cloud form between water transfusions. In these regions, the grasses re-grow obviously. It indicates that water flooding cloud accelerate the Partial restoration. According to above conclusions, the main suggestions are listed as follows: Ecological water transfusion should be implemented without stoppage in the future; at the same time, it is prior to protect and extend the trends of ‘change into vegetation’ based on ensuring the stability of ‘stable vegetation’；In addition, it should be covert to stable vegetation for the ‘unstable change’ as possible as we can.
语种	中文
学科主题	在农业、林业上的应用
公开日期	2010-11-12
页码	共73页
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/8120]
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	段含明. 塔里木河下游生态输水过程中指被变化的遥感研究[D]. 中国科学院．新疆生态与地理研究所. 2008.

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