摘要
【目的】土壤是植物生长所需的必要因子,岩溶区高浓度的土壤Ca含量则影响着当地植物的生长发育。研究基于高光谱反演技术为岩溶区土壤Ca含量的快速测量提供参考。【方法】利用广西典型喀斯特区土壤为研究对象,开展土壤反射率光谱与室内理化分析同步测量。在土壤原始光谱反射率的基础上,进一步对土壤光谱进行一阶导数和包络线去除处理,并利用光谱指数法和主成分回归分析法进行土壤Ca的反演研究。【结果】岩溶区土壤钙含量与土壤光谱之间具有非常高的相关性,在600 nm和2300 nm附近出现较高的峰值,且经过一阶导数和包络线去除处理后的土壤光谱反演效果要明显优于原始光谱。其中,一阶导数处理的指数模型RSI(607 nm,2370 nm)的R2达到0.67,均方根误差为26.34,反演效果最好;包络线去除处理的NDSI(599 nm,601 nm)的R2为0.57,均方根误差为18.24;原始光谱的NDSI(603 nm,604 nm)的R2为0.57,均方根误差为27.94。主成分回归分析的R2为0.57,均方根误差11.92,也具备较好的反演能力。【结论】指数反演中RSI指数具有波段指示意义明确,反演精度高等优点,而主成分回归分析的精度高,分析快,但无法筛选敏感波段。该研究结果证明了高光谱手段反演岩溶区土壤Ca含量的可行性,并为快速获取岩溶区土壤Ca含量的相关研究提供了指导意义。
[Objective]Soil is a necessary factor for plant growth,and high concentration of soil Ca in karst area affects the growth and development of local plants.This study based on hyperspectral inversion technology provides a reference for rapid measurement of soil Ca content in karst area.[Method]In this study,reflectance spectra and indoor physical and chemical analysis of the soil in the typical karst areas in Guangxi were measured simultaneously.On the basis of the original spectral reflectance of soil,the first derivative and envelope of soil spectrum were further removed,and the inversion of soil Ca was studied by spectral index and principal component regression analysis.[Result]There is a very high correlation between soil calcium content and soil spectrum in karst area.There are high peaks near 600 nm and 2300 nm,and the inversion effect of soil spectrum after the first derivative and envelope removal is obviously better than the original spectrum.Among them,RSI(607 nm,2370 nm)R2 is 0.67,RMSE is 26.34;NDSI(599 nm,601 nm)R2 is 0.57,RMSE is 18.24;NDSI(603nm,604nm)R2 is 0.57,RMSE is 27.94.The R2 of principal component regression analysis is 0.57,and RMSE is 11.92.[Conclusion]RSI index has the advantages of clear band indication and high inversion accuracy in index processing;principal component regression analysis has the advantages of high accuracy and fast analysis,but it is unable to screen sensitive bands.The results show that the method of hyperspectral inversion of soil Ca content in karst area is feasible,it also provides guidance for rapid acquisition of Ca content in karst soil.
作者
倪隆康
何文
顾大形
NI Long-kang;HE Wen;GU Da-xing(College of Horticulture and Gardening,Yangtze University,Jingzhou,Hubei 434025,China;Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain,Guangxi Institute of Botany,Chinese Academy of Sciences,Guilin,Guangxi Zhuang Autonomous Region 541006,China)
出处
《江西农业大学学报》
CAS
CSCD
北大核心
2020年第1期203-212,共10页
Acta Agriculturae Universitatis Jiangxiensis
基金
广西喀斯特植物保育与恢复生态学重点实验室项目(17-259-23,18-A-02-01,19-050-6)
国家自然科学基金项目(41401211,41830648)
广西植物研究所基本业务费项目(桂植业18015，桂植业18005)
广西科技重大专项(桂科AA17204087-9-1)~~
关键词
喀斯特
高光谱反演
光谱指数
土壤钙含量
karst area
hyperspectral inversion
spectral index
soil calcium content
