基于卫星遥感技术的赣江尾闾河势演变分析

Satellite remote sensing-based analysis on river regime evolution of tail-section of Ganjiang River

赣江尾闾地区是包括南昌市在内的江西省经济发展的核心区域,赣江作为江西省内第一大河,其尾闾地区河势变化对其周边地区的经济、防洪、环境等有着巨大的影响。运用卫星遥感技术,对1991—2010年赣江尾闾地区赣江的河道进行了河势演变的研究分析,得出了以下结论:(1)研究区域水域面积1991年约为121 km^2、2001年约为111 km^2、2010年约为132 km^2,经历了先减小后增加的变化过程。(2)历年来尾闾地区的变化主要集中在赣江主干、西支、北支,主干变化最为显著,而南支相对最为稳定。(3)主干的变化主要表现为河道扩张、江心洲面积大幅减小或者消失,其中在南昌市附近河道变化最为明显。推测这些变化主要是由人为影响包括有关工程建设、河砂开采等引起。(4)西支变化较为复杂,其上游段主要表现为河道展宽、水域面积变大,而下游段河道有所束窄;北支历年来均表现为河道束窄、江心洲面积明显增大;中支有所变化,但并不明显。

As the area of the tail-section of Ganjiang River（ the first large river in Jiangxi Province） is the core area including Nanchang City for the economic development of Jiangxi Province,and then the river regime variation of its tail-section area has a great influence on the economy,flood control,environment,etc. of its surrounding regions. The river regime evolution of the channel of Ganjiang River from 1991 to 2010 within its tail-section area is studied and analyzed herein with the satellite remote sensing technology; from which it is concluded that（ 1） the water area in the study area experiences a changing process of decreasing at first and then increasing,i. e. about 121 km^2 in 1991,about 111 km^2 in 2001 and about 132 km^2 in 2010.（ 2） the variations over the years in the tail-section area of Ganjiang River are mainly concentrated on its main stream,west branch and north branch,especially the variation of the main stream is most significant,and relatively,the variation of the south branch is most stable.（ 3） the variation of the main stream of Ganjiang River is represented as the expansion of the river channel and the areas of the central shoals are largely reduced or disappeared,especially the variations of the channel near Nanchang City are most significant; for which it is supposed that the variations are mainly caused by human impacts including engineering constructions,sand mining,etc.（ 4） the variation of the west branch of Ganjiang River is more complicated,i. e. its upstream section is mainly represented as the expansion of the river channel along with the enlargement of water area,while the downstream channel is contracted in some extent. The channel of the north branch of the river is represented as the contraction of the river channel over the years and the area of its central shoals are significantly enlarged as well,while the mid-branch of the river is varied in some extent,but it is not so significant.