基于多源空间数据的塔里木河下游湖泊变化研究

利用历史图件、地形图及遥感数据监测塔里木河下游诸多湖泊水域面积并分析近一百多年的变化情况。根据湖泊水域及其变化,该区湖泊在100多年内变化过程可以分为3个时间段：① 20世纪60年代以前,该区水文条件较好,19世纪末20世纪初湖泊总面积超过2000 km²;20世纪60-70年代至20世纪末,随着水利设施的陆续兴建,湖泊水域缩小,甚至某些湖泊彻底干涸;21世纪随着塔里木河流域综合治理与下游生态输水工程的实施,该区水文条件有所好转,干涸多年的一些湖泊重新形成水域,2013年湖泊水域总面积达760 km²。② 根据湖盆成因及水域变化把该区湖泊分为：河道西侧的风成湖,河道网之间及东侧的河成湖及河道末端的构造湖等三类。③ 初步总结风成湖演变过程,发现该区风成湖与河成湖在形状、深度、水质、形成时间等方面有较大差异。④ 近代人为因素对湖泊水域变化的影响高于自然因素。

Evolution of small lakes in lower reaches of Tarim Riverbased on multi-source spatial data

The study on environmental protection and ecological restoration in the lower reaches of the Tarim River has aroused widespread concern in the community and government at all levels. For those studies, the observation of the various forms of water resources is very important, because almost all natural processes and human activities are directly or indirectly restricted by lackage of water resources in the Tarim River Basin. In this research, the lakes in lower reaches of Tarim River were selected as an object, water body information was extracted from historical maps, topographic maps and satellite images, over the past century. Based on water body information and some other ancillary data, evolution of those lakes was analyzed, and the following results were summarized. (1) According to location, wate rbody and their change trends, evolution of the lakes could be divided to three time segments of the study period. Before the 1960s, hydrological conditions of the lower Tarim River were better than in recent 50 years, the number of the lakes was large, and most of the lakes were larger. For example, from the end of the 19th century to beginning of the 20th century, the total water body of the lakes were more than 2000 km². From the 1960s-1970s to the end of 20th century, along with the construction of water conservancy facilities, hydrological conditions in this region tended to be worse, water bodies were reduced or completely dried up in many lakes. In this century, as an one of important results of Ecological Water Transfusion Project, hydrological conditions were improved, some lakes were refilled with water, and they were dried up over the decades. For example, in 2013, the total water area of the lakes in this region reached 760 km². (2) The lakes of the lower Tarim River can be categorized into three main classes, in terms of types of lake basins. The lakes are distributed west of national highway and the right side of the mainstream is typical eolic (wind-formed) lakes; The lakes distributed on the east side of the mainstream and among the river network are riverine (fluvial) lakes; Tetima Lake can be identified as a tectonic lake. (3) Evolution of eolic lakes in this region has been summarized, and compared with riverine lakes in the same region. And we found that, there are great differences between eolic lakes and riverine lakes, in the aspects of shape, depth, water quality, formation time, etc. (4) In modern days, human factors exert more effects on the lake changes of this region than natural factors.