基于HJ小卫星影像的北京市冬小麦测产研究

粮食产量的估测对制定粮食政策和调整种植结构具有重要的意义。本研究以北京市为例,利用2013年4月30日、5月12日和5月29日三期冬小麦抽穗、灌浆时期的HJ小卫星NDVI数据,结合北京市实产地块数据建立了北京市冬小麦估产回归模型,并对北京市各区县和北京全市的冬小麦单产进行了估算。结果显示:分区县地块回归的北京市冬小麦主产区大兴、房山、通州和顺义的小麦单产分别为5148.96 kg/hm2、4849.30 kg/hm2、5350.64kg/hm2和5108.84 kg/hm2,P值分别为0.000、0.000、0.000和0.001;北京市全市的冬小麦单产为5049.24 kg/hm2,精度验证的结果显示实测单产和预测单产具有良好的对应关系,其R2=0.92,RE=2.18%,RMSE=154.61 kg/hm2。以上研究结果表明利用HJ小卫星的NDVI数据可以快速、准确的估算北京市及其各区县的冬小麦单产。

Estimation of winter wheat yield in Beijing based on HJ-1 images

The grain production estimates is crucial to food policy and cropping structure adjustment. In this paper, crop yield estimation models for winter wheat were built by using NDVI data derived from HJ-1 images and ground survey data in Beijing. The results show that predicted productivities of winter wheat in Daxing, Fangshan, Tongzhou and Shunyi, the main agricultural regions of Beijing, were 5148.96 kg/hm2, 4849.30 kg/hm2, 5350.64 kg/hm2 and 5108.84 kg/hm2 respectively. The winter wheat yield of Beijing was 5049.24 kg/hm2 in 2013. Results of accuracy assessment indicate that there is a very strongly correlation between ground survey data and predicted productity (R2=0.92, RMSE=154.61 kg/hm2, RE=2.18%), which suggests that NDVI from HJ-1 images could be used for estimating winter wheat yield in Beijing.