多时相MODIS影像的浙江省水稻种植面积信息提取方法研究

Mapping paddy rice planting area in Zhejiang Province using multi-temporal MODIS images

为准确获取水稻种植面积,以浙江省为研究区,利用8d合成MODIS陆地表面反射率数据的特点和水稻典型物候特征,选取水稻种植前的休耕期、秧苗移栽期、生长期和成熟期等多时像MODIS地表反射率影像数据,通过归一化植被指数、增强植被指数及利用对土壤湿度和植被水分含量较为敏感的短波红外波段计算得到的陆地表面水指数进行水稻种植面积信息获取,将提取结果同现状水田与MODIS影像共同提取的数据以及浙江省统计年鉴数据进行对比分析.结果表明,利用MODIS影像的8d合成地表反射率数据进行平原区域水稻种植面积提取,精度可达90%以上.因此,采用MODIS影像数据进行平原区域水稻遥感监测可以为政府决策部门提供信息服务.

Multi-temporal MODIS images were selected to acquiring paddy rice coverage exactly according to the different paddy rice growth stages, including the flooding and transplanting period, growing period, maturation period, and the fallow period after harvest. A mapping algorithm using time series of three vegetation indices （LSWI, EVI, and NDVI） derived from MODIS images to identify that initial period of flooding and transplanting in paddy rice field, based on the sensitivity of LSWI to the increased surface moisture during the period of flooding and rice transplanting. The algorithm was run to map paddy rice information in Zhejiang Province, using 8-day composite MODIS surface reflectance produces in 2001. The paddy rice data extracted were compared with land use map and MODIS images and Zhejiang statistical yearbook data. The results show that the preeisions of estimating paddy rice planting area with time series MODIS data exceeded 90% in the plain regions. Therefore, it could be applied to monitor paddy rice information at large spatial seales, and provide information services for the government departments.