基于RS和GIS技术的京郊西北地区土地利用变化的景观过程响应

应用遥感与地理信息系统技术,对3期TM影像(19891、996、2005)进行解译判读,获取北京西北地区的土地利用数据.同时应用土地利用时空演变模型、土地利用动态度模型和景观生态学方法,从景观格局的角度定量分析1989—2005年间区域景观过程对土地利用变化的响应.结果表明:近16年来耕地、沙荒地和未利用地的面积明显减少,而城市及建筑用地和林地的面积在连续增加;各景观组分间的转移过程频繁,其中耕地斑块向城市及建筑用地斑块的转移数量最大,沙荒地向林地的转变最为明显;1989—1996年间的综合土地利用动态变化率较1996—2005年间的大,变化集中表现在西北城郊过渡区域;各景观类型的平均斑块形状趋于简单,景观多样性、均匀度指数和破碎度指数呈现增加趋势,而优势度指数在逐渐减小;城市及建筑用地的不断扩张,林地景观平均斑块面积持续减小,并呈现破碎化,是土地利用变化的景观生态过程响应.要实现区域土地资源的可持续发展和景观生态功能的良性发挥,须注重土地利用格局优化,维护景观生态过程与格局的连续性.

Landscape processing response analysis on the land use change in northwest of Beijing based on RS and GIS technologies.

Land use change has been affecting the function and structure of landscape ecological system directly or indirectly,and it influences the landscape processing in the surface of the earth.In this paper,based on the technologies of remote sensing(RS) and geographical information system(GIS),the authors studied three TM images(thematic mapper) of 1989,1996 and 2005 and obtained land use data in northwestern region of Beijing.Then the spatial and temporal evolution models of land use and landscape dynamics model and landscape ecological method were used to analyze the impacts and responses of landscape processing on land use change from 1989 to 2005. The results indicated that the areas of arable land,sandy badlands and unutilized land decreased obviously,while those of forestland increased,urban and built-up land expanded dramatically in recent sixteen years.There was a significant shifting from sandy badlands to forestland,water body changed slightly and the fastest changed area was urban fringe.The temporal and spatial variation characteristics of land use types showed that the comprehensive dynamic change rate from 1996 to 2005 was obviously smaller than that from 1989 to 1996,and changes mainly concentrated in rural-urban fringe.The main landscape types were arable land and forestland in the field region,but the dynamics and the processing of landscape of these two types were different.The patch shape was dispersed and simplified,and the indices of landscape diversity,evenness and fragmentation tended to increase while the dominance index decreased gradually.So it is essential to intensify the spatial relationships among landscape elements and to maintain the continuity of landscape ecological process and pattern in the course of city expansion.