葡萄叶片叶绿素含量高光谱估测模型研究
2018-10-22牛鲁燕张晓艳郑纪业孔庆富王风云
牛鲁燕 张晓艳 郑纪业 孔庆富 王风云
摘要:针对传统方法测定叶绿素含量存在的不足,采用高光谱技术建立了快速、准确、无损估测葡萄叶片叶绿素含量的方法。以采自泰安万吉山基地的葡萄叶片的高光谱反射率和SPAD值为数据源,在分析SPAD值与原始光谱反射率、原始光谱反射率一阶导数、高光谱特征变量间相关性的基础上,筛选敏感波段,建立了基于高光谱反射率的葡萄叶片叶绿素含量估测模型,即SPAD=59.352+44836.313R′601,其中R′601为601 nm波段原始光谱反射率一阶导数。
关键词:葡萄;叶绿素;高光谱;光谱特征
中图分类号:S123文献标识号:A文章编号:1001-4942(2018)07-0152-04
Abstract In view of the shortage of traditional monitoring methods for chlorophyll content, the hyperspectral technology was used to estimate the chlorophyll content in grape leaves rapidly, accurately and nondestructively. With the hyperspectral reflectance and SPAD value of grape leaves collected from the Wanjishan Base in Taian as data, the correlation between the SPAD value and the original spectral reflectance, spectral reflectance derivative and high spectral value were analyzed, and then the sensitive bands were screened out. Based on these, we established the estimation model of chlorophyll content in grape as SPAD=59.352+44836.313R′601, in which, R′601 was the spectral reflectance derivative of 601 nm brand.
Keywords Grape; Chlorophyll; Hyperspectral; Spectral features
葉绿素含量在指示植物营养胁迫、光合作用能力和生长状况等方面具有重要作用。传统的叶绿素含量测定一般采用破坏性的分光光度法,不仅繁琐、费时,而且野外条件下样本的保存及运输都存在困难。SPAD-502型叶绿素仪可以无损地即时测量植物叶片的叶绿素相对含量(SPAD值),使用简单、方便,且SPAD值与叶片的实际叶绿素含量显著正相关[1],可以很好地表征植物叶片的叶绿素变化趋势,但该方法只能逐点对单个叶片进行测量,测定结果受叶片大小、厚薄影响较大,需取多次测定结果的平均值作为最终测定结果,工作量大[2]。
高光谱遥感是一种快速、无损的监测技术,可在不破坏植物组织结构的前提下,实现对作物生长季营养状况的监测[3,4]。目前国内学者对高光谱遥感技术在作物生长监测方面的研究多集中在水稻[5]、玉米[6,7]、小麦……
