生态建设工程对鄱阳湖区域土地利用/覆被变化的影响

生态建设工程可在很大程度上快速改变区域土地利用/覆被格局。本文以鄱阳湖区域三个典型村落为研究对象,利用遥感手段和实地调研获取研究区生态建设工程实施前(2000年)、后(2013年)土地利用信息,在此基础上,结合农户问卷调查,从土地利用程度综合指数(L_j)、土地利用重要性指数(C_i)、林草植被覆盖度(I)指数等方面,分析土地利用变化特征。结果表明:总体上,生态工程建设实施后,鄱阳湖典型村落土地利用程度均呈下降趋势,林草植被覆盖度呈上升趋势。这对于改善鄱阳湖区域生态环境质量具有重要的意义。不同生态建设工程对鄱阳湖区域典型村落土地利用变化影响差异明显。其中,退田还湖工程引起的土地利用变化的重要性指数相对较高,对综合土地利用程度和林草植被覆盖度影响最大;“一大四小”工程引起的土地利用变化的重要性指数也相对较高。单一的“一大四小”工程对土地利用程度和林草植被覆被度的影响较小,但“一大四小”工程与退田还湖工程重合部分使土地利用程度下降,林草植被覆盖度提升。退耕还林工程引起的土地利用变化的重要性指数相对较低,其对土地利用程度和林草植被覆盖度影响较大。

Effect of ecological construction projects on land use/cover changes in the Poyang Lake area

Ecological construction projects can quickly change land use and cover (LUC)to a large extent. This paper took three typical villages in Poyang Lake area as our research objects and used high-resolution remote sensing images for land use and cover field study. We shaped the village LUC map for the years 2000 and 2013,before and after ecological construction projects. Based on this information and household questionnaires we analyzed land use/cover change (LUCC)in the three typical villages via LUCC indexes,such as land use degree Index,LUCC importance Index,and the forest and grass cover rate index. Our results shows that from 2000-2013 under a context of ecological construction projects and farmland abandonment,the land use degree decreased and the forest and grass cover rate increased. Different types of ecological projects had different impacts on LUCC. The LUCC importance index caused by returning farmland to lake is relatively high,and this project had a big influence on land use degree index and the forest and grass cover rate index. The LUCC importance index caused by the One Big Target and Four Little Target project is also high; the single One Big Target and Four Little Target project had little impact on land use degree and forest and grass cover rate. However,the combination of this project and returning farmland to lake made the land use degree decrease and forest and grass cover rate increase. The LUCC importance index caused by retuning farmland to forest is relative low,but it had a big influence on land use degree decline and the forest and grass cover rate.