不同地下水埋深条件下胡杨叶片光谱特征分析  

Spectral features of the Populus euphraticaleaves under different groundwater depth

作　　者：林海军[1] 李霞[1] 牛婷[1] 赵钊[1,2] 

机构地区：[1]新疆农业大学草业与环境科学学院,乌鲁木齐830052 [2]西安市环境保护科学研究院,西安710061

出　　处：《干旱区资源与环境》2013年第11期80-85,共6页Journal of Arid Land Resources and Environment

基　　金：国家自然科学基金(40961027;30460010);新疆草地资源与生态实验室共同资助

摘　　要：用HR-768型光谱仪,实地测定塔里木河下游不同地下水埋深条件下胡杨叶片高光谱数据及其含水率。结果表明:胡杨叶片含水率随地下水埋深下降而降低,但其实测光谱曲线对地下水埋深梯度变化并无明显的响应规律。用ENVI软件去除实测光谱数据包络线后,得出1455nm附近胡杨叶片归一化光谱曲线对地下水埋深梯度变化具有明显的响应规律。采用相关系数法分析所测光谱与含水率的关系,结果表明:1466～1646nm波段是胡杨叶片光谱对水分响应的敏感波段。以1466～1646 nm波段胡杨叶片光谱水分吸收深度和实测含水率构建胡杨含水率估测模型:Y=7.309X1474-5.77X1482-0.629(R2=0.954),模型预测值与实测值的相对误差在1.02%～2.73%之间,平均相对误差为1.59%,模型精度较高。这一研究将为使用高光谱数据进行胡杨生境监测与反演提供依据。HR-768 field-portable spectrora diameter was applied to measure the hyper-spectral data of the leaves of Populus euphratica growing in the stands with different groundwater depths and water contents.The water content of P.euphratica’s leaves decreased with depth of groundwater descending.There was almost no effect of spectral curve to the change of groundwater depth.When the continuum of spectral curves were removed by ENVI.P.euphratic’s spectral curves were obviously related to the change of groundwater depth nearby the band 1455 nm.The relationship between the water content of the samples and the reflectance spectrum have analyzed by using correlation coefficient method.The result showed that the band 1466～1646 nm was the most hypersensitive band.According to the water absorption deepth in the bands of 1466～1646 nm to establish the linear model： Y= 7.309X1474-5.77X1482-0.629（R2=0.954） which was used to forecast the water content of P.euphratica.The relative errors were 1.02%～2.73%.The result showed that an average relative error predicted by the model was 1.59%.The model has high precision.The research provided evidence for the monitoring of Populus euphratica and inversion by using remote sensing data.

关 键 词：地下水埋深 高光谱 相关分析 胡杨 塔里木河下游 

分 类 号：Q945.17[生物学—植物学]