Grassland productivity

Productivity, understood as tons per hectare of dry biomass of regional grassland pastures. Estimated from an empirical model between biomass field measurements and the seasonal integral of the NDVI curve.生产力被定义为区域草原牧场干生物质的公顷产量（单位：吨/公顷）。该指标基于生物量野外实测数据与归一化差值植被指数（Normalized Difference Vegetation Index，NDVI）曲线季节积分值之间的经验模型估算得到。