花期苹果树冠氮素营养状况的卫星遥感反演  

Satellite remote sensing retrieval of canopy nitrogen nutritional status of apple trees at blossom stage

作　　者：王凌[1] 赵庚星[1] 朱西存[1] 王瑞燕[1] 常春艳 

机构地区：[1]山东农业大学资源与环境学院/土肥资源高效利用国家工程实验室,山东泰安271018

出　　处：《应用生态学报》2013年第10期2863-2870,共8页Chinese Journal of Applied Ecology

基　　金：高校博士点基金项目(20103702110010);国家自然科学基金项目(41271369);山东省自主创新专项(2012CX90202);中国博士后基金项目(20110491616)资助

摘　　要：以山东栖霞为研究区，基于TM和ALOS影像获取花期苹果树的冠层反演反射率，结合实测反射率，构建并筛选氮素敏感光谱指数，以敏感光谱指数为自变量，建立氮素反演模型，利用精度最高模型进行空间反演．结果表明：光谱指数与氮素营养相关性为：冠层〉叶〉花，敏感指数构成以绿、红、近红外波段为主；反演模型精度为：支持向量机回归〉逐步回归〉丹变量回归；基于不同影像的反演结果近似，叶N含量均以3～4等（27～33g·kg-1）为主，冠N指标均以2～4等（TM：38～47g·kg-1；ALOS：32～41g·kg-1）为主；基于不同影像的空间布局亦类似，研究区北部和南部的营养水平高于中部，叶N和冠N高等级区域位于西北部的苏家店镇和松山街道、东北部的臧家庄镇和亭口镇、南部的蛇窝泊镇等，与苹果生产重点镇布局一致．此研究为果树营养状况的宏观数据获取提供了可行方法，也可为其他类似遥感反演提供借鉴．Taking Qixia City of Shandong, China as the study area, and based on the Landsat-5 TM and ALOS AVNIR-2 images, the canopy retrieval reflectance of apple trees at blossom stage was ac- quired. In combining with the measured reflectance of sample trees, the nitrogen-sensitive spectral indices were constructed and selected. By using the sensitive spectral indices as the independent variables, the nitrogen retrieval models were established, and the model with the best accuracy was used for spatial retrieve. The correlations between the spectral indices and the nitrogen nutritional status were in the order of canopy 〉 leaf 〉 flower. The sensitive indices were mainly composed of green, red, and near infrared bands. The accuracy of the retrieval models was in the order of sup- port vector regression 〉 multi-variable stepwise regression 〉 one-variable regression. The retrieval results based on different images were similar, and showed that the leaf nitrogen content was mainly of grades 3-4 （27-33 g ~ kg-1 ）, and the canopy nitrogen nutrient indices were mainly of grades 2-4 （TM： 38-47 g ~ kg-1; ALOS： 32-41 g ~ kg-~）. The spatial distribution of the retrieval nitro- gen nutritional status based on different images also showed the similar trend, i. e. , the nitrogen nu- tritional status was higher in the north and south than that in the middle part of the study area, and the areas with the high grades of leaf nitrogen and canopy nitrogen were mainly located in Sujiadian Town and Songshan subdistriet in the northwest, Zangjiazhuang Town and Tingkou Town in the northeast, and Shewopo Town in the south, which were consistent with the distribution of the key towns for apple production in Qixia City. This study provided a feasible method for the acquisition of nitrogen nutritional status of apple trees on macroscopic scale, and also, provided reference for oth- er similar remote sensing retrievals.

关 键 词：苹果树 花期 氮素营养 遥感反演 

分 类 号：S127[农业科学—农业基础科学] TP79[自动化与计算机技术—检测技术与自动化装置]