SO2污染环境下水稻导数光谱与生理生化指标的相关性研究

THE CORRELATION BETWEEN DERIVATIVE SPECTRA AND SOME BIOPHYSICAL-BIOCHEMICAL INDICES OF RICE UNDER SO_2 POLLUTION

通过田间开顶式小区熏气试验,研究在SO2急性伤害条件下水稻冠层导数光谱与叶片含硫量、叶液pH值以及叶绿素含量的相关性。分别选择分蘖期和抽穗期显著相关的波段(分蘖期:689 nm、584 nm、570 nm;抽穗期:689 nm、584 nm、585 nm)建立预测叶片含硫量、叶液pH值及叶绿素含量的回归模型,并分别用拔节期和灌浆期相应导数光谱反射率检验模型预测精度。结果表明,由分蘖期建立的回归模型估测拔节期叶液pH值及叶绿素含量与实测值之间相关系数分别为0.884和0.630;由抽穗期建立的回归模型估测灌浆期的叶片含硫量及叶绿素含量与实测值之间相关系数分别为0.659和0.768,均通过显著检验。

Field experiments were conducted in a split plot with three rice varieties. Rice samples were exposed to sulfur dioxides of different concentrations inside a fumigation chamber. After the measurement of visible and near infrared radiance of the canopies of rice, leaves of rice canopy were sampled to analyze pH of extracted leaf fluid and chlorophyll concentration and sulfur content of rice leaves. The correlation between these biophysical - biochemical indices and the first derivative spectral reflectance shows that the first derivative spectral characteristics which are significantly correlated with sulfur content, pH and cholorophyll concentration can be selected to estimate the biophysical -biochemical indices with regression models using 689nm, 584nm and 570nm at the tiller stage, and using 689nm, 584nm and 585nm at the heading stage respectively. The first derivative spectral reflectance of 689nm, 584nm and 570nm at the jointing stage, and 689nm, 584nm and 585nm at the filling stage can be used to test the accuracy of regression models. The correlation coefficients between measured values of the jointing stage and estimated values of the tiller stage for estimating models are 0. 498 （ sulfur content）, 0.884 （pH） and 0. 630 （ chlorophyll concentration） respectively. In addition, the correlation coefficients between measured values of heading stage and estimated values of filling staeg were 0. 659 （ sulfur content）, 0.768 （ chlorophyll concentration） and 0.50 （pH） respectively.