运用实测高光谱数据对梭梭同化枝叶绿素的估算

Estimating Leaf Chlorophyll Content of Assimilating shoots of Haloxylon ammodendron with the Measured Hyperspectral Remote Sensing Data

叶绿素是植物光合作用过程中最重要的色素,与植被的光能利用及转化效率密切相关。以荒漠生态系统建群种梭梭(Haloxylon ammodendron)为研究对象,通过收集64种叶绿素光谱指数,对这些指数在梭梭同化枝叶绿素面积质量反演的适用性进行评价,利用实测光谱数据对梭梭同化枝叶绿素进行相关性分析。结果表明:64种光谱指数在梭梭同化枝叶绿素反演的精度很低;对梭梭同化枝叶绿素面积质量解释性较好的光谱指数有R600/R1630、R600-R1605、(R600-R1630)/(R600+R1630)、D1815-D1290、D1210/D1290、(D1210-D1290)/(D1210+D1290);极端的干旱气候及长期的水分胁迫导致梭梭同化枝叶绿素的光谱响应特征具有独特性。

Chlorophyll is the most important pigment in the photosynthetic process of vegetation, which is closely related to the light energy utilization and conversion efficiency. Chlorophyll is the representation of the plant nutrition, and could be used as the indictor of plant stress and interference from external environment factors. The rapid and nondestructive acquisition of leaf chlorophyll is a one of the important topics in the vegetation remote sensing research. Through the correlation between the 64 published spectral indices and the assimilating shoots chlorophyll of Haloxylon ammodendron, the published spectral indices were not suitable for estimating the chlorophyll of H. ammodendron. The following indices, R600/R1630,(R600-R1605),(R600-R1630)/(R600+R1630),(D1815-D1290), D1210/D1290,(D1210-D1290)/(D1210+D1290), have good relationship with the assimilating shoots chlorophyll of H. ammodendron. Extreme drought climate and long-term water stress lead to the unique spectral response characteristics of chlorophyll.