不同水氮条件下水稻冠层反射光谱与叶片水势关系的研究

Relationship Between Canopy Reflectance and Leaf Water Potential in Rice UnderDifferent Soil Water and Nitrogen Conditions

研究了不同水氮处理对水稻叶片水势及冠层光谱的影响,确立了叶片水势与冠层反射光谱的相关关系。结果表明,水稻叶水势随土壤含水量的升高而升高;在相同干旱胁迫下,低氮处理的叶水势高于高氮处理的叶水势。研究发现,比值指数与归一化指数的比值与水稻叶片水势、相对含水率呈良好的线性相关,从而获得了一种地面遥感监测水稻全生育期叶片水势的定量方法。

The investigation was conducted to study the relationship between canopy reflectance characteristics and leaf water potential in rice under different water and nitrogen levels. The results showed that the rice leaf water potential increased with the enhancement of soil water content. Under the same soil drought status, leaf water potential under high nitrogen level was lower than that under low nitrogen level. The ratio of RVI and NDVI was linearly related to leaf water potential and leaf relative water content, and thus can be used to monitor leaf water status over growth period of rice.