基于SPOT VGT/NDVI的陕西省关中地区冬小麦遥感估产

冬小麦是关中地区的主要粮食作物之一。对冬小麦产量估算的研究可使国家有关部门及时掌握粮食生产状况,对国家制定粮食政策和经济计划,及时进行宏观调控有着重要的意义。以陕西省关中地区为研究区域,利用1999—2007年的SPOT VGT/NDVI遥感数据对冬小麦产量进行预测。首先,选取冬小麦关键生长期内0.2—0.8范围内的旬NDVI数据,利用最大值合成法合成后的月NDVI数据建立与冬小麦产量之间的关系;其次,使用相关分析方法筛选出冬小麦关键期内与产量相关性较好的月份和旬,分别建立这些月份、旬与冬小麦产量之间的回归关系模型,最后对模型进行精度验证。结果显示,NDVI与产量之间有很好的相关性,其中4月上旬的相关性最好,其相关系数R2为0.605,即利用4月份上旬的数据预测冬小麦产量最好。在预测产量与实际产量对比的基础上,得出估产的相对误差为-5.2%—-7.9%,表明估产精度良好,可运用于冬小麦的实际估产。

Estimation of Winter Wheat Yield in Guanzhong Area of Shanxi Province Using SPOT VGT/NDVI

Winter wheat was one of the major food crops in Guanzhong area of Shanxi Province.In this study,SPOT VGT/NDVI data,which obtained from 1999 to 2007,were used to estimate the winter wheat yield in Guanzhong area of Shanxi Province.First,monthly NDVI data was generated based on ten days NDVI data(value was 0.2 to 0.8) during February to May by the maximum synthesis method.Then the relationships was established between monthly NDVI and winter wheat yield,ten days NDVI and winter wheat yield respectively.At last,the model which had the best correlation coefficient was selected,and its accuracy was verified.In the result,correlation coefficients were high between NDVI and winter wheat yield,and the best was in early April(R2=0.605).Using this model to estimate winter wheat yield,the relative error was-5.2%—-7.9% between actual production and forecast production.Through this study,it showed that winter wheat yield estimation accuracy was good,and SPOT VGT/NDVI could be used in estimating winter wheat yield.