近20年塔里木河干流生态环境变化遥感监测分析

针对塔里木河流域综合治理后生态环境的变化状况及植被的恢复状况等热点问题,基于遥感时空变化分析方法从土地利用、地表水体和植被覆盖度的时空变化方面分析了近20年来塔里木河干流生态环境的变化状况。结果表明:(1)塔里木河干流土地利用受到人类活动的影响显著,自2000年以来,塔里木河干流耕地面积增加显著,净增2 229 km~2,草地面积整体下降,萎缩3 157 km~2;(2)综合治理以来,下游河段2009—2018时段水体出现频率明显高于2000—2008时段,水体出现频率提高约15%;(3)2000年以来,塔里木河流域的植被覆盖度持续增加,特别是下游河段植被覆盖度增加明显,覆盖度增加18%。但中、上游流域的植被覆盖度的增加趋势主要贡献来源于耕地,中上游地区耕地的增加仍会对塔里木河流域的生态保护和恢复造成一定的影响。

Analysis on remote sensing monitoring of eco-environment variationof main stream basin of tarim river in recent 20 years

Aiming at the hotspot issues，i． e． the status of the eco-environment variation，the status of the vegetation restoration，etc． after the comprehensive improvement of Tarim Ｒiver Basin，the changing status of the eco-environment of the main stream basin of Tarim Ｒiver in recent 20 years is analyzed from the aspect of land-use，surface water and the vegetation coverage on the basis of the remote sensing． The results show that ( 1) the land-use within the main stream of Tarim Ｒiver is significantly influenced by the human activities，and the cultivated area is remarkably increased with the net increment of 2 229 km2 ，while the grassland area is generally decrease with the decrement of 3 157 km2 ; ( 2) after the comprehensive improvement，the occurring frequency of water body within the period of 2009—2018 in the lower river reach is obviously higher than that in the period of 2000—2008，for which the occurring frequency of water body is increased about 15%; ( 3) since 2000，the vegetation coverage within the main stream of Tarim Ｒiver Basin is continuously increased，especially the obvious increase of vegetation coverage in the lower reach with the increment of the coverage of 18%． However，the vegetation coverage increasing trends of the upper and the lower reaches are mainly contributed by cultivated land，while the increases of the cultivated land areas in the upper and the lower reaches are still to make certain influences on the protection and restoration of the main stream basin of Tarim Ｒiver．