摘要
粮食安全问题一直倍受世界各国关注,及时、准确地了解其他国家或地区的粮食生产状况,对于中国粮食贸易和粮食宏观调控,具有十分重要的意义。本文以美国冬小麦和玉米为研究对象,在分析各作物空间分布及生长季节的基础上,利用土地利用数据剔除非耕地信息,使提取的归一化植被指数(NDVI)客观地反映各作物的生长状况。以1998—2007年的SPOTVEGETATION旬最大值合成NDVI资料为数据源,研究了美国玉米和小麦生长季的旬NDVI与产量的关系,确定了不同月份的建模因子,分别建立了美国玉米和冬小麦不同月份的产量动态预报模型。通过对各模型估算产量与实际产量进行比较,各模型预报结果的相对误差大部分在3%以内,精度较高,说明建立的作物产量动态预报模型实用可行,能够投入产量预报业务应用。
Grain security is a key issue having been concerned with all over the world. To understand the crop growth status in other countries and regions timely and accurately is of significance for China＇ s grain trade and grain macro-control. In this paper, a case study was made on the corn and winter wheat production in USA. Based on the analysis of the spatial distribution and growth periods of the crops, the information of non-cultivated land was eliminated from land-use and land-cover data, making the extracted NDVI could objectively reflect the growth status of the crops. After analyzing the relations between actual crop yields and ten-day-composite NDVI in 1998-2007 based on the data from SPOT VEGETATION, the variables of dynamic yield estimation models for the crops were determined, and the models were established. The comparison of the crop yields estimated by the models and the actual crop yields showed that the relative errors of estimated yields were mostly within 3%, illustrating that the established dynamic crop yield estimation models had a high accuracy, being feasible and practicable.
出处
《生态学杂志》
CAS
CSCD
北大核心
2009年第10期2142-2146,共5页
Chinese Journal of Ecology
基金
国家科技部"十一五"科技支撑项目(2006BAD04B04)
中国气象局业务建设资助项目
