济宁市植被覆盖度时空格局演变分析

Analysis on spatiotemporal pattern evolution of vegetation coverage in Jining City

文中为研究2000~2019年济宁市植被生态环境时空格局变化状况,研究以MODIS-NDVI为数据源,利用GIS与RS技术,对其不同时期植被覆盖度计算,并引入多种动态变化模型对其时空格局演变状况进行定量分析。结果表明:(1)济宁市植被覆盖整体表现出明显垂直分布的空间变化特征,具体呈现为由北向南植被覆盖度有逐渐降低的变化趋势,同时各等级植被覆盖度区域在空间分布上也表现出明显的差异;(2)研究将区域植被覆盖度分为低覆盖、中低覆盖、中覆盖、中高覆盖和高覆盖5个等级,各等级间面积比例差异明显,面积比例为中高覆盖>中覆盖>高覆盖>中低覆盖>低覆盖;(3)变化幅度和单一动态度变化表明,近20年内该地区中高覆盖区面积有部分减少,而其他区域面积均为增加状态,并且低植被覆盖区增加的幅度和速度均最明显;(4)趋势分析则表征出整个时段内,区域植被整体发展状态较差;(5)质心模型显示,经过20年的变化,区域植被整体向东北迁移0.98km,可见研究区北部植被保护效果较南部更为明显。

In order to study the spatiotemporal pattern change of the vegetation eco-environment in Jining City from 2000 to 2019, MODIS-NDVI was used as the data source, GIS and RS technology were used to calculate the vegetation coverage in different periods, and a variety of the dynamic change models were introduced to analyze quantitatively the spatiotemporal pattern evolution. Results showed that:(1)The overall vegetation coverage showed the obvious vertical distribution of the spatial change characteristics in Jining City, specifically showed the decreasing trend from north to south, and the spatial distribution of each grade of the vegetation coverage area also showed the obvious differences;(2)The regional vegetation coverages were divided into the low coverage, the medium and low coverage, the medium coverage, the medium and high coverage and the high coverage, and there were the significant differences in the area ratio of each grade, the area ratio was medium and high coverage>medium coverage>high coverage>medium and low coverage>low coverage;(3)The change range and the single dynamic degree showed that the area of middle and high coverage areas in this area had decreased, while the acreages of other areas had increased in recent 20 years, and the increase range and speed of the low vegetation coverage areas were the most obvious;(4)Trend analysis showed that the overall development status of the regional vegetation were poor in the whole period;(5)The centroid model showed that the overall regional vegetation moved to the northeast by 0.98 km after 20 years of change, which showed that the effect of the vegetation protection in the north of the study area was more obvious than that in the south.