摘要
通过对江西省吉安县不同有机质含量土壤的光谱曲线吸收特征进行分析,得到不同有机质含量土壤的光谱曲线特征响应波段,建立了县级尺度基于有机质响应波段的定量估算模型。结果表明,红壤和水稻土土壤光谱曲线特征具有明显差异,560-710 nm为吉安县土壤有机质含量的特征吸收波段;基于特征吸收波段范围的吸收面积（s）的对数和有机质含量的相关性为0.86,拟合方程为y=-20.91 ln（s）-27.26,决定系数为0.74,经不同类型土壤的有机质数据检验,预测的决定系数（R2）、均方根误差（RMSE）和预测相对分析误差（RPD）分别为0.75、0.61和1.88;包络线去除和反射率的倒数的对数处理建立的偏最小二乘回归（PLSR）模型预测效果最佳,预测决定系数均达0.83以上,相对偏差均为2.4以上,基于特征吸收波段560-710 nm建立的模型能定量估算红壤地区有机质含量,为土壤有机质估测提供参考。
The objectives of the study were to analyze spectral characteristics of red soils different in SOM（ soil organic matter） content in Ji＇an,Jiangxi,for establishment of county-scale SOM quantitative estimation models based on SOM reflectance bands,it was found that red soil and paddy soil differed sharply in soil spectral characteristic. The wave range of 560 ～ 710 nm was the spectral absorption band specific of SOM in the soils of Ji＇an county. Correlation coefficient of the log of the absorption area in the range of characteristic absorption bands with soil SOM was 0. 86,fitting equation was y =- 20. 91 ln（ s）- 27. 26,and determination coefficient was 0. 74. After calibration with the data of SOM in various types of soils,the determination coefficients for prediction（ R2）,the root mean square error（ RMSE） and the relative error analysis（ RPD） was found to be 0. 75,0. 61 and 1. 88,respectively. The partial least squares regression（ PLSR）model,established on continuum removal and logarithm processing of reciprocal of the reflectance,was the highest in estimation accuracy,with prediction determination coefficient R2 being over 0. 83,RMSE less than 5. 00 and RPD more than2. 4. These findings indicate the model based on specific absorption bands 560 ～ 710 nm can be used to quantitatively estimate soil SOM in red soil regions.
出处
《土壤学报》
CAS
CSCD
北大核心
2014年第5期1003-1010,共8页
Acta Pedologica Sinica
基金
国家自然科学基金项目(41361049)
土壤与农业可持续发展国家重点实验室开放基金项目(0812201202)
江西省自然科学基金项目(20122BAB204012)资助
作者简介
方少文（1964-），男，博士研究生，主要从事土壤遥感信息和水土保持的研究。E—mail：jac1030@163．com
通讯作者，E—mail：zhaoxm889@126．com
