重金属污染水稻的冠层反射光谱特征研究

利用野外光谱仪获取矿区农田重金属污染水稻的冠层反射光谱，通过曲线模拟和统计分析提取了与水稻冠层叶片重金属含量变化极显著相关的光谱敏感波段(Pb, 460 nm;Zn, 560 nm;Cu, 660 nm;As, 1 100 nm)、归一化植被指数(Pb, NDVI_{(510, 810)};Zn, NDVI_{(510, 870)};Cu, NDVI_{(660, 870)};As, NDVI_{(510, 810)})和“红边”位置等水稻冠层反射光谱特征。表明水稻重金属污染可以被地面遥感传感器快速检测，其浓度变化与所提取的光谱特征之间存在极显著相关，归一化植被指数与“红边”位置对光谱信息的表达要优于敏感波段。归一化植被指数以及“红边”位置可以作为水稻重金属污染遥感监测模型的光谱特征参数选择参考。同时，文章提出了利用遥感技术监测水稻重金属污染的“光谱临界值”概念, 并计算出研究中各重金属对应的“光谱临界值”。

Study on Canopy Spectral Characteristics of Paddy Polluted by Heavy Metals

Because of frequent mining,heavy metals are brought into environment like soils,water and atmosphere,resulting heavy metal contamination in the agricultural region beside mines.Heavy metals contamination causes vegetation stress like destruction of chloroplast structure,chlorophyll content decrease,blunt photosynthesis,etc.Spectral responses to changes in chlorophyll content and photosynthesis make it possible that remote sensing is applied in monitoring heavy metals stress on paddy plants.Field spectroradi...