基于遥感技术的地表水源地植被覆盖度的动态变化

植被覆盖及其动态变化可以有效地反映出区域环境变化特征,监测植被变化在评价区域生态环境质量中是不可缺少的一部分。数据源采用Landsat遥感影像,在运用归一化植被指数及像元二分模型的基础上,提取出2002、2009、2018年珲春老龙口水库地表水源地植被覆盖度,并进行动态变化分析。结果表明:2002—2018年珲春老龙口水库地表水源地区平均植被覆盖度值呈先减少后增加的趋势,2009—2018年,该研究区植被覆盖度处于相对良好的状态,中高度植被覆盖区与高度植被覆盖区占总面积的比重达到86.99%。从空间上来看,地表水源地的东北部分植被覆盖度较高,由东向西呈降低趋势。高植被覆盖区变化明显,近20年内增加了1 818.80 km~2。政府政策、生态恢复工程、人类活动等是影响珲春老龙口水库地表水源地植被覆盖度的主要因素。

Dynamic Change of Vegetation Coverage of Surface Water Source Based on Remote Sensing Technology

Vegetation cover and its dynamic changes could effectively reflect the characteristics of regional environmental changes. Monitoring vegetation changes was an indispensable part of evaluating the ecological environment quality of the region. The data source of this paper adopts Landsat remote sensing image, based on the normalize difference vegetation index and dimidiate pixel model to calculate the vegetation coverage of the surface water source field of the Laolongkou Reservoir in Hunchun in 2002, 2009 and 2018, and carry out the analysis of dynamic change. The results show that the average vegetation coverage value of the surface water source area of Laolongkou Reservoir in Hunchun from 2002 to 2018 increased after decreasing, the overall vegetation coverage in this area was relatively good between 2009 and 2018, with the medium height and high-vegetation coverage areas accounting for 86.99% of the total area. In terms of space, the vegetation coverage in the northeast of the surface water source is high, and it decreased from east to west. The high vegetation coverage area has changed significantly, with an increase of 1818.80km2 in the past 20 years. Government policies, ecological restoration projects, and human activities are the main factors affecting the vegetation coverage of surface water sources of the Laolongkou Reservoir in Hunchun.