USDA NASS Cropland Data Layer (CDL)

The USDA, NASS Cropland Data Layer (CDL) is a raster, geo-referenced, crop-specific land cover data layer with a ground resolution of 56 meters. The CDL is produced using satellite imagery from the Indian Remote Sensing RESOURCESAT-1 (IRS-P6) Advanced Wide Field Sensor (AWiFS) collected during the current growing season. Ancillary classification inputs include: the United States Geological Survey (USGS) National Elevation Dataset (NED), the USGS National Land Cover Dataset 2001 (NLCD 2001), and the National Aeronautics and Space Administration (NASA) Moderate Resolution Imaging Spectroradiometer (MODIS) 250 meter 16 day Normalized Difference Vegetation Index (NDVI) composites. Agricultural training and validation data are derived from the Farm Service Agency (FSA) Common Land Unit (CLU) Program. The NLCD 2001 is used as non-agricultural training and validation data. The strength and emphasis of the CDL is agricultural land cover. Please note that no farmer reported data are derivable from the Cropland Data Layer.

美国农业部（USDA）国家农业统计服务局（NASS）农田数据层（CDL）是一款栅格地理配准的作物专属土地覆盖数据集，地面分辨率为56米。该数据集依托当前生长季采集的印度遥感资源卫星一号（IRS-P6）先进宽视场传感器（AWiFS）所获取的卫星影像制作而成。其辅助分类输入数据包括：美国地质调查局（USGS）国家高程数据集（NED）、美国地质调查局2001年国家土地覆盖数据集（NLCD 2001），以及美国国家航空航天局（NASA）中分辨率成像光谱仪（MODIS）250米分辨率16天合成归一化差分植被指数（NDVI）组合产品。农业训练与验证数据源自美国农场服务局（FSA）公共土地单元（CLU）计划，NLCD 2001则被用作非农业训练与验证数据。CDL的核心优势与重点方向为农业土地覆盖分类。请注意，无法从农田数据层中获取农户上报的相关数据。