Song Xiao-Ning, Ma Jian-Wei, Li Xiao-Tao, Leng Pei, Zhou Fang-Cheng, Li Shuang
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
Remote Sensing Technology Application Center, China Institute of Water Resources and Hydropower Research, Beijing 100048, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2013 Oct;33(10):2833-7.
Vegetation canopy water content (VCWC) has widespread utility in agriculture, ecology and hydrology. Based on the PROSAIL model, a novel model for quantitative inversion of vegetation canopy water content using Hyperion hyperspectral data was explored. Firstly, characteristics of vegetation canopy reflection were investigated with the PROSAIL radiative transfer model, and it was showed that the first derivative at the right slope (980 - 1 070 nm) of the 970 nm water absorption feature (D98-1 070) was closely related to VCWC, and determination coefficient reached to 0.96. Then, bands 983, 993, 1 003, 1 013, 1 023, 1 033, 1 043, 1 053 and 1 063 nm of Hyperion data were selected to calculate D980-1 070, and VCWC was estimated using the proposed method. Finally, the retrieval result was verified using field measured data in Yingke oasis of the Heihe basin. It indicated that the mean relative error was 12.5%, RMSE was within 0.1 kg x m(-2) and the proposed model was practical and reliable. This study provides a more efficient way for obtaining VCWC of large area.
植被冠层含水量(VCWC)在农业、生态学和水文学领域有着广泛的应用。基于PROSAIL模型,探索了一种利用Hyperion高光谱数据定量反演植被冠层含水量的新模型。首先,利用PROSAIL辐射传输模型研究了植被冠层反射特征,结果表明,970nm水吸收特征(D98 - 1070)右斜率(980 - 1070nm)处的一阶导数与VCWC密切相关,决定系数达到0.96。然后,选取Hyperion数据的983、993、1003、1013、1023、1033、1043、1053和1063nm波段来计算D980 - 1070,并采用所提方法估算VCWC。最后,利用黑河流域英科绿洲的实测数据对反演结果进行验证。结果表明,平均相对误差为12.5%,均方根误差在0.1kg·m⁻²以内,所提模型实用可靠。该研究为大面积获取VCWC提供了一种更有效的方法。