Suchergebnisse

International audience ; Dynamic change of vegetation has become a very sensitive problem in China due to climate variability and human's disturbances in the Yellow river basin. Dynamic simulation and forecast of vegetation are regarded as an effective measure to decision support for local government. This paper presents a new method to support the local government's effort in ecological protection. In integrates cellular automata (CA) -artificial neural network (ANN) model with Geographical information system (GIS) and remote sensing. The proposed method includes three major steps: (1) to extract control factors; (2) to integrate CA and ANN models; (3) to simulate the selected area using CA-ANN model. The results indicted that the integrated approach can rapidly find condition of future vegetation cover that satisfy requirement of local relative department. It has demonstrated that the proposed method can provide valuable decision support for local government. the result indicts that NDVI of the vegetation has an increasing trend and characteristics of distribution concentration trend, but the change rate is become lower from the year 2007 to 2014 compared with the changes from the year 2000 to 2007.

International audience ; Excessive water is used by farm field in Tarim river basin, it is very important to deep study on the relation between area of farm field and natural vegetation in recent 50 years. Collecting and processing various decades of remote sensing data, and got area of farm field, grass, forest, town and non-serviceable field. These results indict that: Because of the high flow period between 1950 and 1972, a part of grassland converts forest. From 1972 to 1990, because of increase of farm field, limited water isn't enough to grassland and forest, and a fraction of forest area converts grassland again. With rapid increase of area of farm field, more water need from the river and underground, which causes water level depression, and natural ecology becomes deteriorative from 1990 to 2000. Comprehensive analysis indicts that agriculture control implemented by government is necessary to recovery of ecology, or farm field also would be lost eventually with destruction of natural ecology.