Study On Landscape Spatial Pattern And Effects On Eco-environment In Liujia Watershed Based On GIS

This text is based on the figures and pictures in 1976 and 2004 in the investigation area, collaborating with the field investigation, categorized system of the landscape elements which is based on the vegetation dominant species was established, the landscape elements in liujia watershed Pingshun county was categorized into six primary classification and eleven second classification. Supported by GIS software Arc View3.2 and Spatial analyst, the landscape elements pattern charts in the area was protracted ,and the database was established. The reasonable landscape pattern index was chosen . The spatial distribution, landscape spatial pattern, landscape heterogeneity, interaction relationship among the different landscape elements, the dynamic changes were analyzed, landscape elements categorizing drawing was overlapped. The transformation matrix of the different periods was computed, the process of the dynamic changes of land use was analyzed,. The ecological environment of the watershed was evaluated by ecological environment quality indices .The result shows: the complexity of the landscape elements has a trend to decrease. The landscape heterogeneity of the watershed decreased, the relationship among the landscape was closer than ever. After the transformation of nearly 30 years, The landscape elements which is dominant in 1976 and 2004 changes. The main landscape elements was waste slopes which is natural landscape in 1976,while in 2004 manual forestland dominates which is artificial landscape, the vegetation coverage is more than 70%; The regional environment quality rise from 0.2523 in 1976 to 0.6690 in 2004.The fossa waste slopes and watershed began to disappear, and the manual forestland grass slope with a proper coverage and open forests began to appear. The quality of ecological environment changes greatly. The other landscape type which changes into manual forestland contributes lot to the regional environment quality,. The main driving factor which lead to the changes of regional environment is disturbance. The disturbance changes natural landscapes with a low quality into manual landscapes with a high quality. During the course ,the spatial distribution become more and more reasonable. The research offer the scientific proof for the forest ecological construction, optimization of agriculture forest ecosystem structure regional plan regional environment construction regional ecological safety and developing strategy.