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传统湖泊面积制图一般选取一年中某一天的湖泊状态代表某段时间的湖泊面积状况,无法反映湖泊面积的变化信息.利用中等分辨率成像光谱仪(MODIS)8天500 m分辨率的合成数据,通过样本自动选取与支持向量机(SVM)水体识别相结合,获得了中国2000~2010年629个主要湖泊每8天的湖水分布范围.比较2000年湖泊制图结果与同期30 m分辨率湿地解译湖泊分布图,发现MODIS湖泊水体制图具有较高的精度(生产者精度91.06%,用户精度89.81%).基于该多时相数据库分析了629个湖泊的面积变化、波动性、淹没程度以及丰水期.中国主要湖泊总面积呈增加趋势,主要来自青藏高原湖泊面积扩张.2000~2010年最大面积大于1000 km2的湖泊有12个,其中6个在萎缩.鄱阳湖萎缩速率最大,为54.76 km2a 1,洞庭湖萎缩速率为25.08 km2a 1.青藏高原、新疆北部、内蒙古东北部和东北地区湖泊面积波动性小,长江中下游、内蒙古南部、新疆中部湖泊波动性大.青藏高原、新疆北部、黑龙江、吉林湖泊淹没强度增加,而新疆中部、西藏南部、内蒙古南部、四川、长江中下游湖泊淹没强度减少.湖泊面积的高时间频率制图是从通用地表覆盖制图向高频率专一地表覆盖类型制图的尝试,对湖泊水文研究将是一种重要的数据补充,同时基于更准确的湖泊水淹等动态地表覆盖状况,将有可能开发更准确的新一代陆面过程模式,从而提高模式模拟效果.
Traditional lake area charting usually selects the lake status of a certain day of the year to represent the lake area status for a period of time and can not reflect the change of the area of the lake.Using the synthetic data of the resolution of 500 m with 8-day MODIS, Through the automatic selection of samples and support vector machine (SVM) water body recognition, we obtained the lake water distribution range of 629 main lakes in China every 8 days from 2000 to 2010. Comparing the results of lake mapping in 2000 with the interpretations of wetland of 30 m in the same period According to the multi-temporal database, the area change, volatility, inundation degree and abundance of 629 lakes were analyzed, and the results showed that the water quality of MODIS lakes showed a high accuracy (91.06% accuracy and 89.81% accuracy) The total area of main lakes in China showed an increasing trend, mainly due to the expansion of lakes in the Qinghai-Xizang Plateau. Twelve lakes with a maximum area of more than 1000 km2 in 2000-2010, of which 6 were atrophy, had the largest shrinkage rate of 54.76 km2 a , The atrophy rate of Dongting Lake is 25.08 km2a. 1. The fluctuation of lakes area in the Qinghai-Tibet Plateau, northern Xinjiang, northeastern Inner Mongolia and northeast China is small. In the middle and lower reaches of the Yangtze River, In southern Mongolia and central Xinjiang, the lakes fluctuated greatly, and the inundation intensity of lakes in the central Tibet, southern Tibet, southern Inner Mongolia, Sichuan and the middle and lower reaches of the Yangtze River decreased in the Tibetan Plateau, northern Xinjiang, Heilongjiang and Jilin lakes, and the high temporal frequency Cartography is an attempt to map high-frequency-specific surface coverage types from universal surface coverage mapping to an important data complement to lake hydrology and based on more accurate dynamic surface coverage conditions such as lake flooding it will be possible to develop A more accurate new generation of land surface process model, thereby enhancing the model simulation results.