Research On The Change And Recoverary Of Ecological Environment In Qinghai Lake In The Last 15 Years Of 20th Century

Qinghai Lake is located in northeast area of Tibet Plateau, with 2.97 thousand square kilometers of river basin and 4265.3 square kilometers of lake area, which is the largest inland salty lake nationwide and the second largest worldwide. A lot of research job has been done on it because of its unique geographic position and the existence of gigantic Qinghai Lake. The great lake along with its grassland and plants not only controls and adjusts the ecological environment of the lake area but forms a natural screen against the spread of desert from west toward east. It is also an essential water area that guarantees the ecological security of northeast area of Tibet Plateau.In recent century, owing to the influence of weather together with other natural elements, water level has been going down year by year that leads to a series of problems such as deterioration of ecological environment of lake area, which to some extent influenced the source of river, Chaidamu Basin, east of Qilian Mountain as well as ecological environment, agriculture and poultry of Huangshui Valley in east Qinghai province.The thesis begins with primary knowledge of Qinghai Lake with its river basin and research materials from related satellite remote-sensor, and it mainly analyses the historical evolution of Qinghai Lake and data from satellite remote-sensor on areas undergoing relatively great change. It explores into the developing tendency and causes of the tendency, pointing out that the warm and dry weather is the essential reason that leads to the decrease of water input, descending of water level and deterioration of ecological environment in recent century. It adds that human activities make the situation all the more serious. Although the tendency of wet weather in the last decade of 20th century has relieved the problem and a few ecological projects have been launched, the deterioration of ecological environment has made no evident progress.To deal with these problems, a series of measures are put forward in the thesis, namely strengthening management of water resource, enlarging water reserve and planting, speeding up the replacement of farmland with woods and grassland, undertaking comprehensive management cooperating with conservation of soil and water, building ecological oasis, and improving ecological environment of QinghaiLake. It also suggests building dynamic watch-survey system so as to have overall understanding of the effectiveness of the measures taken.