文献类型：期刊文献

英文题名：Nonlinear spectral mixture effects for photosynthetic/non-photosynthetic vegetation cover estimates of typical desert vegetation in western China

作者：Ji, Cuicui[1,2] Jia, Yonghong[1] Gao, Zhihai[3] Wei, Huaidong[4] Li, Xiaosong[2]

第一作者：Ji, Cuicui

通信作者：Li, XS[1]

机构：[1]Wuhan Univ, Sch Remote Sensing & Informat Engn, Wuhan, Hubei, Peoples R China;[2]Chinese Acad Sci, Key Lab Digital Earth Sci, Inst Remote Sensing & Digital Earth, Beijing, Peoples R China;[3]Chinese Acad Forestry, Inst Forest Resources Informat Tech, Beijing, Peoples R China;[4]Gansu Desert Control Res Inst, State Key Lab Desertificat & Aeolian Sand Disaste, Lanzhou, Gansu, Peoples R China

年份：2017

卷号：12

期号：12

外文期刊名：PLOS ONE

收录：;Scopus(收录号：2-s2.0-85038627042);WOS:【SCI-EXPANDED(收录号:WOS:000417905600026)】；

基金：The study was financially supported by National Key Research and Development Program (NO. 2016YFC0500806, http//program.most.gov.cn/), National Natural Science Foundation of China (No.1360204, http/www.nsfc.gov.cn/), National Natural Science Foundation of China (No. 41571421, http.//www.nsfc.gov.cn/).; The work was funded by National Key Research and Development Program (NO. 2016YFC0500806, http://program.most.gov.cn/),National Natural Science Foundation of China (No.1360204, http://program.nsfc.gov.cn/), National Natural Science Foundation of China (No. 41571421, http://program.nsfc.gov.cn/ ).

语种：英文

摘要：Desert vegetation plays significant roles in securing the ecological integrity of oasis ecosystems in western China. Timely monitoring of photosynthetic/non-photosynthetic desert vegetation cover is necessary to guide management practices on land desertification and research into the mechanisms driving vegetation recession. In this study, nonlinear spectral mixture effects for photosynthetic/non-photosynthetic vegetation cover estimates are investigated through comparing the performance of linear and nonlinear spectral mixture models with different endmembers applied to field spectral measurements of two types of typical desert vegetation, namely, Nitraria shrubs and Haloxylon. The main results were as follows. (1) The correct selection of endmembers is important for improving the accuracy of vegetation cover estimates, and in particular, shadow endmembers cannot be neglected. (2) For both the Nitraria shrubs and Haloxylon, the Kernel-based Nonlinear Spectral Mixture Model (KNSMM) with nonlinear parameters was the best unmixing model. In consideration of the computational complexity and accuracy requirements, the Linear Spectral Mixture Model (LSMM) could be adopted for Nitraria shrubs plots, but this will result in significant errors for the Haloxylon plots since the nonlinear spectral mixture effects were more obvious for this vegetation type. (3) The vegetation canopy structure (planophile or erectophile) determines the strength of the nonlinear spectral mixture effects. Therefore, no matter for Nitraria shrubs or Haloxylon, the non-linear spectral mixing effects between the photosynthetic / non-photosynthetic vegetation and the bare soil do exist, and its strength is dependent on the three-dimensional structure of the vegetation canopy. The choice of linear or nonlinear spectral mixture models is up to the consideration of computational complexity and the accuracy requirement.