基于NDVI指数的浑善达克沙地植被时空变化规律分析

Temporal and Spatial Variation Law of Hunshandake Sandy Land Vegetation Based on NDVI Index

为从宏观上认识沙地绿色植被在年、月时间尺度的变化规律,为防沙治沙工作提供理论依据,分析了浑善达克沙地1982—2006年共25年的植被指数数据。研究认为,浑善达克沙地植被生长期为每年的5月下旬至10月,其中7月下旬和整个8月绿色植被生长量达到峰值;1982—2006年的25年间,浑善达克沙地绿色植被覆盖度以每年0.1百分点的速率缓慢增长,其中沙地西部治沙成果显著,但沙地中东部,原本的中、高植被覆盖区,植被的衰退和显著衰退面积竟然高达总面积的27%。同样的防沙治沙工作,为何在浑善达克沙地的东、西部出现了截然相反的局面,这需要引起我们的反思和高度重视。

In order to understand the variation law of sandy green vegetation on time scale of month and year from the macro-view and provide a theoretical basis for desertification control,it analyzed 25-year vegetation index data of Hunshandake sandy land from 1982 to 2006. The research considers that a) the plant growing period of the sandy land is from late May to October each year,of which,the growth of green vegetation in late July and whole August reaches to the peak value and; b) during the 25 years from 1982 to 2006,the green vegetation coverage of the sandy land slowly increases by the annual rate of 0.1 percentage points,of which,the desertification control achievement of the west sandy land is remarkable,while in the central east of the sandy land where used to be medium and high vegetation coverage area,the declined and obviously declined areas of vegetation are even as high as 27% of the total area. For the same desertification control,why there is an opposite situation in the east and west of the sandy land. This should arouse us reconsideration and great attention.