塔里木河干流荒漠河岸林的空间分布与生态保护

塔里木河流域荒漠河岸林具有重要的生态、经济和社会效益。论文以塔里木河干流的荒漠河岸林系统为研究对象,借助于卫星遥感、GIS等技术,结合实地调查,应用缓冲区梯度分析方法,对现有林地水平分布结构进行分析。结果表明:①塔里木河干流荒漠河岸林面积为58.42×10⁴ hm²,占研究区总面积的14.07%,自上而下5个河段的林地面积分别占总面积的2.94%、3.75%、3.95%、1.99%和1.44%,并且北岸河岸林面积较南岸明显多,南岸受沙漠化威胁,河岸林退化严重,水资源时空分配不均匀是荒漠河岸林分布特征的重要原因;②荒漠河岸林多沿河道地形分布,随离河道距离的增加呈波动下降趋势,河流对荒漠河岸林显然具有重要影响,径流主要起到补给地下水的作用,近河床区林地分布较集中,波动幅度小,在远离河床区林地易于退化,河流北岸影响范围为38.33~45.51 km,南岸为15.21~39.33 km;③塔里木河干流总体林地率不高,林地分布不均匀,荒漠河岸林形成以河道为中心的带状分布,分布范围达10~80 km,重要保护范围在0.8~12.3 km,恢复范围在2.2~24.5 km,重建范围在4.7~30.1 km。根据荒漠河岸林的分布特征和保护目标,对塔里木河干流用水作统一规划和协调是符合实际的生态治理措施。

Spatial Distribution Characteristics and Ecological Protection of the Desert Riparian Forest in the Mainstream of the Tarim River

Tarim River riparian forest is highly prized in the Tarim Basin for its great ecological, economic and social benefits. This paper, based on remote sensing images and GIS technology in combination with field survey and the methods of buffer analysis, studies the spatial distribution characteristics of the existing forest. The result shows that: 1) the area of desert riparian forest is 58.42×10⁴ hm²(14.07% of the total). The area of desert riparian forest from upper to lower reaches of the Tarim River accounted for 2.94%, 3.75%, 3.95%, 1.99% and 1.44%, respectively, the width and abundance of desert riparian forest of north bank is larger than that of south bank, where the uneven time and space distribution of water resources is the main cause for the desert riparian forest distribution characteristics. 2) Desert riparian forest is mostly distributed following the channel terrain and decreases with the distance further away from the bank. The runoff has obvious effect on the desert riparian forest recovery which is close to the Tarim River and has less effect on the desert riparian forest recovery which is farther away from the Tarim River. The sphere of influence of the river is 38.33-45.51 km on the north bank and 15.21-39.33 km on the south bank. 3) The rate of forest area in the basin is not high and shows an uneven distribution in the Tarim River. The desert riparian forest is in zonal distribution centering around the river with the distribution range of 10-80 km, the important protection range of 0.8-12.3 km, the recovery range of 2.2-24.5 km and the reconstruction range of 4.7-30.1 km. According to the distribution characteristics of the desert riparian forest and conservation goals, unified planning and coordination of water resources utilization is an effective ecological management measure suitable to local conditions.