芦苇叶片含水量的光谱响应特征分析  

Analysis on Spectrum Feature for Water Content of Phragmites Reed Leaf

作　　者：侯艳军[1] 董琳琳 Hou Yanjun;Dong Linlin(Department of Geography,Xinzhou Teachers University,Xinzhou,Shanxi 034000,China)

机构地区：[1]忻州师范学院地理系,山西忻州034000

出　　处：《激光与光电子学进展》2021年第3期342-349,共8页Laser & Optoelectronics Progress

基　　金：国家自然科学基金(41661057);山西省高等学校科技创新项目(2020L0548);忻州师范学院五台山文化研究项目(201701);忻州市科技局应用基础研究项目(20190105-3)。

摘　　要：对艾比湖湿地自然保护区的芦苇叶片进行了采样、含水量测定,利用FieldSpec3便携式光谱仪现场进行了芦苇叶片的光谱测量,并对芦苇叶片原始光谱进行了平滑处理、导数变换,分析在不同微分窗口尺度下芦苇叶片一阶导数对含水量变化的响应特征,同时提取特征参数表征芦苇叶片含水量。研究表明:当w=1~15时,一阶光谱曲线噪声难以有效降低,致使光谱曲线的轮廓不易辨别,叶片含水量变化引起的光谱响应特征不易判断。当w=16~30时,微分窗口尺度的增大较好地消除了芦苇叶片一阶导数光谱值中的噪声,芦苇叶片一阶导数光谱与含水量之间的相关系数在1460~1500 nm波段与1374~1534 nm波段相比,相关系数波动小,标准差小,表现较稳定,1460~1500 nm波段一阶导数光谱对含水量的响应呈现比较一致、显著的特征;将1460~1500 nm波段内一阶导数光谱值的平均值作为特征参数,在微分窗口尺度1~30下,该特征参数与其他窗口尺度相比,更适合指示芦苇叶片含水量变化,为干旱区湿地芦苇水分遥感监测中采用短波红外反射光谱分析技术定量检验芦苇叶片水分提供新的途径。The reed leaves in Ebinur Lake Wetland Nature Reserve were sampled and water content was measured.The spectrum of reed leaves was measured by FieldSpec3 portable spectrometer.The original spectrum of reed leaves was smoothed and derivative transformation was carried out.The response characteristics of the first derivative of reed leaves to water content change under different differential window scales were analyzed,and the characteristics were extracted.The water content of reed leaves was characterized by characteristic parameters.The results show that when w=1-15,the noise of the first-order spectral curve is difficult to be effectively reduced,which makes the contour of the spectral curve difficult to distinguish,and the spectral response characteristics caused by the change of leaf water content are not easy to judge.When w=16-30,the first derivative spectrum noise obtained can be effectively removed.Compared to the correlation coefficient between the first derivative spectrum of phragmites reed leaves and the water content in the 1374-1534 nm band,the correlation coefficient in 1460-1500 nm band demonstrates small fluctuations,small standard deviations,and stable performance,the response feature between the whole first derivative spectrum within 1460 nm and 1500 nm,and water content variation has more consistency and significantly response.Take the average value of the first derivative spectral value in the 1460-1500 nm band as the characteristic parameter.Under the differential range of 1-30,compare the characteristic parameter with other differential ranges,it is more suitable to indicate the change of reed leaf water content,which provides a new way for quantitative detection of reed leaf moisture by short-wave infrared reflectance spectroscopy in remote sensing monitoring of reed water in arid area.

关 键 词：光谱学 短波红外 芦苇叶片含水量 一阶导数光谱 特征参数 

分 类 号：S151.9[农业科学—土壤学]