大型江心岛景观格局和地表特征参量时空变化及响应——以广阳岛为例

Spatial and Temporal Variation and Response of Landscape Pattern and Land Surface Characteristic Parameters in Large River Island——Taking Guangyang Island as an example

地表特征参量是生态环境质量的重要表征指标,景观格局是地表特征参量变化的重要驱动力。以2002年、2010年、2018年三期Landsat TM/Landsat 8 OLI遥感影像为基础数据源,借助3S技术和景观格局指数相关模型、NDVI模型、地表温度模型以及土壤湿度模型对广阳岛景观格局和地表特征参量的时空演变特征进行分析,并挖掘分析地表参量对景观格局的响应关系。结果表明:(1)研究区景观格局变化较大,各类景观的空间异质性明显,耕地是岛屿主要景观基质;(2)景观破碎度呈现上升趋势,景观整体趋于不稳定;(3)归一化植被覆盖指数和地表温度均呈现先升后降趋势,后期表现出两级分化现象;(4)土壤湿度呈现先稳定后剧降趋势;(5)地表特征参量对景观格局响应明显,特别是地表温度和土壤湿度,人为干预使得区域生态效益下降。本研究为优化流域生态安全格局,合理规划管理土地资源提供科学参考。

The surface characteristic parameter is an important indicator of the quality of ecological environment, and the landscape pattern is an important driving force for the change of the surface characteristic parameter. Based on the Landsat TM/Landsat 8 OLI remote sensing images in 2002, 2010 and 2018, we analyzed the temporal and spatial evolution characteristics of landscape pattern and surface characteristic parameters of Guangyang Island by using 3 S technology, landscape pattern index correlation model, NDVI model, surface temperature model and soil moisture model, and excavated and analyzed the response relationship between surface parameters and landscape pattern. The results show that:(1) the landscape pattern of the study area changed greatly, and the spatial heterogeneity of various landscapes was obvious, and cultivated land was the main landscape matrix of the island;(2) the landscape fragmentation showed an increasing trend, and the landscape overall tended to be unstable;(3) the vegetation coverage and surface temperature showed a trend of first rising and then falling, and later showed two-stage differentiation;(4) the soil moisture showed a trend of first stabilizing and then dramatic;(5) the response of land surface characteristic parameters to landscape pattern was obvious, and human intervention made regional ecological benefits decline. This study can provide a scientific reference for optimizing the ecological security pattern of river basin and reasonably planning and managing land resources.