基于InVEST模型的长江中游经济带生境质量的时空分异特征及其地形梯度效应

Study on the Spatio-Temporal Patterns of Habitat Quality and Its Terrain Gradient Effects of the Middle of the Yangtze River Economic Belt Based on InVEST Model

基于DEM与1995、2005、2015年土地利用数据,通过InVEST模型、GIS空间分析方法评估长江中游经济带生境质量的时空分异特征,并采用回归分析、地形位指数研究生境质量的地形梯度效应。结果表明:(1)长江中游经济带生境质量空间分布差异较大,整体上水平较高。高质量生境主要分布于山地丘陵区及水域,低质量生境分布于农业城市区;(2)1995~2015年,境内高质量生境存在向低质量退化的趋势,平均生境质量略有下降;(3)生境质量变化水平呈现"北部及东部提升-中部及南部下降"的空间格局,江汉平原和江西省东部地区的生境质量有所提升,生境质量下降区域主要位于中部重要城市连接成的环形带上;(4)生境质量存在显著的地形梯度效应,随着地形位提升,高等级生境质量的县级单元数量逐渐增加,平均生境质量相应提升。1995~2015年,1等地形位的生境质量提升,其余等级地形位的生境质量表现为下降趋势。研究结果有助于揭示长江中游经济带生境质量的时空变化过程,可为长江中游经济带生物多样性保护和土地利用规划提供理论支持。

Based on Digital Elevation Model(DEM)and land use data of 1995,2005 and 2015, this paper revealed spatio-temporal patterns and terrain gradient effects of habitat quality in the middle of the Yangtze River Economic Belt by InVEST Model,GIS spatial analysis,terrain index and regression analysis method. The results showed that:(1)The spatial distribution of habitat quality in the middle of the Yangtze River Economic Belt was quite different,and the overall level was relatively high. High-quality habitats were primarily in mountainous hilly areas and waters,while low-quality habitats were mainly distributed in agricultural and urban areas.(2)From 1995 to 2015,the high-quality habitats tended to deteriorate to low quality,with the average habitat quality decreasing slightly.(3)The level of habitat quality change showed a spatial pattern of "northern and eastern improvement-central and southern decline". The habitat quality in Jianghan Plain and the eastern Jiangxi Province had improved,and the areas of habitat quality decline were mainly located in the ring belt connected by the central important cities.(4)Significant topographic gradient effect existed in habitat quality. With the elevation of topography,the number of county-level units of high level habitat quality gradually increased. And the average habitat quality correspondingly increased. From 1995 to 2015,the habitat quality of the 1 st terrain improved,while the habitat quality of the others was declining. The results are conducive to revealing the spatio-temporal changes of habitat quality in the middle of the Yangtze River Economic Belt,and they can also provide theoretical support for biodiversity conservation and land use planning in the middle of the Yangtze River Economic Belt.