Land Use And Coverage Change In The Middle Reaches Of Heihe River Basin And Mechanism Research

Based on the summer and autumn Landsat TM/ETM data of the middle reaches of Heihe River Basin, the thesis has obtained the data of the land use and cover changes in the three periods by compounding artificial color by 4,3,2 bands standard mode and adopting human-computer interaction visual interpretation estimation. The results illustrate that in the former 10 years or in the latter 5 years, both the land use and coverage changes have the same tendency, but their variations are quite different. Resident-land and cropland area are raising greatly, especially in the latter 5 years the raising rate is much faster than that of the former 10 years.Usoing Ordinary Kriging algorithms to interpolate the spatial distribution of temperature, wind speed, relative humidity, sunlight time and precipitation in the research areas. On this condition, the thesis gets the mean value of seven county of research area in 1995 and 2005 respectively.By processing meteorologic observation datas and statisticing economic datas, the thesis puts land use and coverage type area change of research region to spatial correlation analysis with physical driving factors and article driving factors separately. The analysis indicates that relative humidity and sunlight time are important driving factors in physical driving forces, while GDP and net income of farmers are important driving forces in article driving forces about land use and coverage changes of the research region.Through analyzing two phases of research region land use and coverage driving forces(1990-2000,2000-2005), the thesis gets the conclusion that the physical driving forces play a more important role in the former ten years while the article driving forces are dominant factors in the latter five years.