摘要
塔里木河下游地区是我国西部干旱区生态环境问题比较突出的区域。本文主要从地表水(湖泊、河流和湿地)、地下水、地表植被覆盖的角度,基于多源遥感和长时间序列数据,监测和分析生态输水前后区域环境变化和生态响应。首先,采用基于知识迁移的专题图斑更新技术,实现了1990、1995、2000、2005、2010和2015年区域湿地遥感制图和植被覆盖度等生态因子指标提取;然后,以2000年为基准(生态输水起始年),结合地下水位观测数据,对比分析了人工生态输水前后区域生态环境动态变化过程。结果显示:①生态输水前(1990-2000年),塔河下游的生态环境持续恶化,流域范围内一半以上的沼泽湿地消失、河道干涸,地下水位下降,区域植被覆盖大幅度下降;②生态输水后(2000-2017年),区域生态环境明显好转,改变了下游河道长期断流状态,区域地下水位明显抬升,地表水域(湖泊和沼泽)面积呈现"V"型逆转增加,区域植被覆盖区和覆盖度均呈现显著增加趋势,曾经一度干涸的塔河尾闾台特玛湖水域面积2017年8月达到147.87 km2。以上研究结果综合表明人工生态输水工程对塔河下游生态环境拯救和治理发挥了重要作用,遏制了生态输水前塔河下游生态环境继续恶化局面,流域生态环境正在逐步恢复。
The lower reaches of the Tarim River is a region with fragile ecology and significant environmental problems in an arid area of Western China. The local ecological environment has experienced tremendous degradation over the decades, due to water resource deficits from human activities and climate change. In the year 2000, the Tarim River Basin Administration Bureau (TBAB) initiated the Ecological Water Conveyanee Project (EWCP) in an attempt to restore the downstream ecosystem. By the end of 2017, 18 water delivery projects had been completed, totaling 6.3 billion m\ Understanding the effect of water delivery on the ecological environment in the lower reaches of the Tarim River is of environmental importance. This paper monitors and analyses regional environmental changes and ecological responses before and after water conveyance from surface water (lakes, rivers and wetlands), groundwater and vegetation cover, using multi-source remote sensing and long- term series data. Wetland information and updated maps were produced using thematic map plaque knowledge transfer technology. Regional wetlands mapping and area change statistics were then completed for the years 1990, 1995, 2000, 2005, 2010 and 2015. Finally, regional wetland and vegetation change characteristics were analyzed pre- EWCP period (before 2000) and post- EWCP (after 2000). Results indicate that:(1) Pre-EWCP period (1990-2000), the regional ecological environment in the lower reaches of the Tarim River continued to deteriorate (almost half of the swamp wetlands in the basin disappeared and the regional vegetation coverage decreased significantly).(2) Post- EWCP period (2000- 2017), the regional ecological wetlands of the basin. In addition, the areas containing medium and sparse vegetation coverage had a significant increasing trend, and the ecological environment of wetland was gradually restored. Furthennore, the long-term dry and shut?ofT state of the downstream river channcl has been changed. In particular, the Tail Lake (Taitema Lake) gradually regained its vitality after 30 years of becoming dry (area reached 147.87 km2 in Aug. 2017). This research showed that the EWCP played a key role in the rescue and control of the ecological environment in the lower reaches of the Tarim River and hence, the regional ecological environment is gradually recovering. These findings are critical for cnvironmental effect assessments by the EWCP and future ecological restoration effort in the lower reaches of the Tarim River. They may also provide useful technical support and decision- making references for ecological engineering construction and performance evaluation.
作者
朱长明
李均力
沈占锋
沈谦
ZHU Changming;LI Junli;SHEN Zhanfeng;SHEN Qian(Department of Geography and Environment, Jiangsu Normal University, Xuzhou 221116, China;Institute of Xinjiang ecologyand geography , Chinese Academy of Sciences, Urimuq 830011, China;Institute of Remote Sensing and Digital Earth, ChineseAcademy of Sciences, Beijing 100101, China;University of Chinese Academy of Sciences, Beijing 100049, China)
出处
《地球信息科学学报》
CSCD
北大核心
2019年第3期437-444,共8页
Journal of Geo-information Science
基金
国家重点研发计划项目(2017YFB0504204)
国家自然科学基金项目(41671034,41201460,U1178302).
关键词
塔里木河下游
生态环境
遥感
生态调水
动态监测
lower reaches of the Tarim River
ecological environment
remote sensing
ecological water conveyance
dynamic monitoring
