翅碱蓬高光谱植被指数对土壤化学性质的响应

Hyperspectral Vegetation Indices of Suaeda Salsa in Response to Changes of Soil Chemical Properties

植被覆盖区土壤化学性质遥感监测一直是一个难点,往往只能通过生物地球化学的方法,利用上覆植被信息间接地反映。该研究通过野外采样分析的17个翅碱蓬(Suaeda salsa)光谱数据和其下土壤样品的理化分析配对数据,探讨土壤化学性质与翅碱蓬高光谱植被指数间的关系。结果表明:上覆翅碱蓬高光谱植被指数与土壤有机质、全氮、速效钾之间均无显著相关,高光谱植被指数(NDNI)可用于初步反映土壤全磷的含量变化,NDVI705可用于初步反映土壤pH值的变化,而高光谱植被指数(MSI)可以很好地反映土壤盐分含量的变化。在此基础上,建立了土壤全盐量与19个高光谱植被指数的偏最小二乘回归模型,这为翅碱蓬覆盖区域土壤盐渍化遥感监测提供了一种方法。

It is difficult to monitor soil salinization at the regions covered by vegetation.In general,the above covered vegetation information was used to indirectly monitor the soil chemical properties on the basis of bio-geochemical method.In this paper,Suaeda salsa spectra and soil property data were gotten through measurement of seventeen paired-samples,which were used to study hyperspectral vegetation indices of Suaeda salsa in response to changes of soil chemical properties.The results showed that there were not significant relationship between hyperspectral vegetation indices and organic matter,total nitrogen and available potassium of soils,and NDNI and NDVI705 could be elementarily used to reflect total phosphorus and pH of soils respectively,and MSI could be used to monitor soil salt content very good.Finally the partial least squares regression model between soil salt content and the nineteen hyperspectral vegetation indices was made,which indicated that soil salt content was beneficial to Suaeda salsa growth,and MSI could be used as the index for monitoring soil salinization at the regions covered by vegetation.