岷江上游近30年土地利用/覆被空间格局变化的图形信息分析

The Graphical Information Analysis of Spatial Pattern Change of Land Use/Cover during Lately 30 Years in Upper Reaches of Minjiang River

利用遥感的方法获取岷江上游1972～2 0 0 0年土地利用/覆被状况及其动态变化数据,从图形表达与分析的角度入手,运用地理图形信息理论,结合GIS空间分析方法,探讨岷江上游近30a的土地利用空间格局变化的图形特征及其描述方法。研究认为:土地利用/覆被动态变化的图形信息是全面研究土地利用/覆被变化的一个有机组成成分,可以从图形的角度对土地利用/覆被变化信息进行挖掘;由于岷江上游人类活动对土地的扰动增加和土地的破碎度增加,该区重要的覆被类型———林地持续遭到破坏,林地的边缘趋于复杂化,反映了人文驱动力(包括人口压力、社会经济活动、政策调控等)对土地利用/覆被变化在30a时间尺度内的重要影响。要恢复和重建岷江上游生态屏障功能,必须提高全民的环境保护意识以及制定和执行相应的政策、法规,加强资源和环境的保护和合理利用,恢复森林、草地生态系统,搞好退耕还林还草,加强天然林保护以及大面积有规划的植树造林,控制畜牧数量,改良天然草地,治理退化草地,控制水土流失。

Different land use pattern has its distinct graphical feature owing to different contributing mechanism condition, and spatial structure of land use lies in specific geological graph evolving by time series. This paper attempts to acquire land use/cover situation and its dynamic changing data from 1972 to 2000 in upper reaches of Minjiang River by the application of RS, and thus further explores the land use spatial pattern, changing graphics features and its descriptive method in this region in nearly 30 years from the angle of graph indication and analysis applying geological graph information theory in combination with spatial analysis of GIS. The research shows the graph information of land use/cover dynamic change is one essential component of a comprehensive study of land use/cover. The frequent human activities on lands, increasing broken lands, continuous destruction on the important cover-plant type-woodland, and the edges of forest tending complication all reflect the determining influence of human driving force including population pressure, social economic activities and policy operating on land use/cover change in lately 30 years. Therefore, in order to recover and rebuild the ecological defense, it is necessary to promote the public awareness of environmental protection and the making and executing of correspondent policies and laws, and to strengthen the protection and reasonable utilization of resources and environment with the focus put on restoring ecological system of woodland and grassland, withdraw from farmland, Intensifying forest protection as well as planting trees in a large scale, controlling livestock farming, improving natural grassland, managing deteriorate grassland and stopping up washed-away soil and water.