基于遥感技术的人工速生林二氧化碳吸收量估测

选择宁夏中卫市中冶·美利纸业集团的林纸一体化人工速生杨基地作为研究对象,以CBERS/CCD影像和同步实测样地数据为基础,利用相关分析方法筛选出相关系数分别为0.939和0.936的NDVI和RVI两个变量,构建了基于NDVI、RVI及NDVI和RVI的3个人工速生林地叶面积遥感回归估测模型,R2分别为0.882、0.877和0.885,并通过相关检验,估算出研究区不同林龄速生杨林地的叶面积。结合样地的实测净光合速率（PN,Net Photosynthetic Rate,μmol·m-2·s-1）,推算出不同林龄的速生杨单位叶面积的年二氧化碳净吸收量,最终估算出整个研究区的年固定碳（CO2）的净增量分别为326 648.66、315 688.73和322 509.04 t。通过与常规方法测得结果的比较,表明遥感结合地面实测数据估算林木固碳是可行的;从建立模型的R2值分析,根据不同植被指数建立的多元模型的精度要优于单一植被指数建立的一元模型;根据估测结果,随着林龄的增长,林木的固碳能力不断提高,但受不同生境的影响,增长速度存在空间差异。

Carbon sequestration of artificial FAST-growing forest of poplar based on RS technology

The base of poplar forest and paper integration of Zhongye Meili Paper Industry group in Zhongwei city was taken as a case study,in terms of the CBERS/CCD image and synchronous plot data,as well as the method of correlation analysis screen out two variables NDVI and RVI.The correlation coefficients（R2） between leaf area and NDVI and RVI were 0.939 and 0.936,respectively.Three regressive models were developed based on NDVI,RVI,NDVI and RVI,respectively.The R2 of three models were 0.882,0.877 and 0.885,respectively.All the models passed the correlation examination.The leaf areas of fast-growing forest according to the different stand age in the target plot were estimated.And then,estimated the unit leaf area’s amount of CO2annually stored with the PN（Net Photosynthetic Rate,μmol·m-2·s-1） of field measurement.Finally,estimated the amount of CO2 annually stored of the target plot is 326 648.66,315 688.73 and 322 509.04 t,respectively.