泾河沿岸景观格局梯度变化及驱动力分析  

Gradient variations in landscape pattern along the Jinghe River and their driving forces

作　　者：毕晓丽[1] 周睿 刘丽娟[1] 洪军[1] 王兮之[1] 王辉[1] 索安宁[1] 葛剑平[1] 

机构地区：[1]北京师范大学生命科学学院,北京100875

出　　处：《生态学报》2005年第5期1041-1047,i006,共8页Acta Ecologica Sinica

基　　金：国家"973"计划资助项目 (G2 0 0 0 0 4680 2 ) ;国家"973"计划资助项目 (2 0 0 2 CB1115 0 7) ;高等学校博士学科点专项科研基金资助项目(2 0 0 0 0 0 2 716) ;国家自然科学基金资助项目 (3 0 2 70 2 5 4)~~

摘　　要：以MODIS影像数据为基础,利用Fragstats为工具,对泾河主干沿岸做10 km缓冲区(Buffer) ,从景观水平和类型水平上,分析河岸带景观格局的梯度变化,同时对产生这种梯度变化的驱动力进行分析。结果表明泾河自上游而下,景观水平上的景观指数有3种不同的变化类型:(1)上升型(2 )下降型(3)无明显趋势,表现出斑块数量、丰富度、连接度的递增,形状指数、分维数和斑块大小的递减;类型水平上以农田、草地和农草交错类为主,这3种类型的景观指数表现突出,具有明显的峰值。景观格局的梯度变化受到温度、降水、土壤等影响,同时,人为干扰也是不可忽视的重要因素,经济发展,人口增加使景观类型及其分布格局发生巨大的变化。景观格局的数量化对生态系统评估、监测起重要的作用。Jinghe river is originated at the Liupan Mountains of Shannxi province in Northwest China, and is one of the secondary tributaries of the Yellow River. The Jinghe River basin is located on the Loess Plateau which is notorious for its widespread problem of soil degradation and wind erosion. The native ecosystems of the Jinghe River basin exhibit gradient changes from the upper ranges to the lower ranges, and all are rather vulnerable to human disturbances because of their fragile environment. The goals of this study are two-fold: (1) to quantify the gradient variations in land use and land cover pattern along the main channel of the Jinghe River using landscape metrics, and (2) to explore the driving forces that may have caused the gradient changes in this riverine landscape. Based on MODIS remote sensing data for the year of 2002, we identified nine land use and land cover types using unsupervised classification techniques, and georeferenced them with global position system (GPS) points. The most dominant land use and land cover types are farmlands and grasslands. Forests, although rare, are also found in this region. To analyze the riverine landscape pattern, we created a buffer zone along the main channel of the Jinghe River with a buffer width of 10 km. The land use map and the river buffer map were overlaid, and the analysis was conducted with a moving window (10×15 km) starting from the upper edge of the river buffer area downward. A selected group of landscape metrics was used to quantify the changing pattern of land use and land cover in the study region. All of the analyses were performed using a geographic information system (GIS) and the landscape pattern analysis software, FRAGSTATS. Our results showed that the landscape metrics exhibited three different kinds of variations at the landscape scale: (1) increasing, (2) decreasing, and (3) no consistent trend. In particular, patch number, patch richness, and patch connectivity all increased from the upstream to the downstream of the Jinghe R

关 键 词：河岸景观 缓冲区 梯度分析 景观指数 泾河 

分 类 号：P901[天文地球—自然地理学]