修复过程中盐渍化土壤的光谱特征分析（英文）

Spectral Characteristics of Salinized Soils during Microbial Remediation Processes

该研究跟踪山东东营盐渍化土壤（盐分主要以氯化钠为主）的微生物修复盆栽实验,分析研究修复过程中土壤理化性质的改良以及相应的光谱特征变化。基于对修复过程中不同阶段土壤盐分含量（SSC）和Na^＋,Cl^-等理化指标的化学分析及其同步的光谱测试,采用平均值降维方法,相关系数与决定系数相结合的方式,通过逐步缩小采样间隔,分析了土壤在微生物修复过程中盐分和盐分离子含量变化及其光谱响应的最佳波段和特征。结果表明,土壤在不同处理的微生物修复过程中,全波段平均光谱反射率与SSC的变化趋势和幅度几近一致,与Cl^-含量变化趋势和幅度完全一致。在光谱测试的全波段范围内,SSC及盐分离子含量与光谱反射率呈显著正相关,在近红外波段的反射率变化尤为显著。在此基础上,基于调整光谱采样间隔方法分析获得的盐分及其离子含量最佳光谱响应波段反射率,建立了土壤光谱反射率与盐分含量及其离子含量的关系模型。其中SSC的最佳响应波段1 370-1 445和1 447-1 608nm,Cl^-,Na^＋的最佳响应波段分别为1 336-1 461和1 471-1 561nm,建立的模型其R^2最高值达到了0.95,RMSEC,RMSEP最大值分别为1.076和0.591。不同处理的土壤微生物修复结果的显著性统计分析及其相应的光谱特征变化,充分显示了土壤盐分含量的光谱响应特征及其敏感性,对发展基于高光谱的土壤盐渍化快速分析诊断方法具有重要意义。

In this study,the spectral reflectance of saline soils,the associated soil salt content（SSC）and the concentrations of salt ions were measured and analysed by tracing the container microbial remediation experi-ments for saline soil （main salt is sodium chloride）of Dongying City,Shandong Province.The sensitive spec-tral reflectance bands of saline soils to SSC,Cl^- and Na^＋ in the process of microbial remediation were ana-lysed.The average dimension reduction of these bands was conducted by using a combination of correlation co-efficient and decision coefficient,and by gradually narrowing the sampling interval method.Results showed that the tendency and magnitude of the average spectral reflectance in all bands of saline soils during the total remediation processes were nearly consistent with SSC and with Cl^- coocentration,respectively.The degree of salinity of the soil,including SSC and salt ion concentrations,had a significant positive correlation with the spectral reflectance of all bands,particularly in the near-infrared band.The optimal spectral bands of SSC were 1 370 to 1 445 nm and 1 447 to 1 608 nm,whereas the optimal spectral bands of Cl^- and Na^＋ were 1 336 to 1 461 nm and 1 471 to 1 561 nm,respectively.The relationship model among SSC,soil salt ion concentrations （Cl^- and Na^＋ ）and soil spectral reflectance of the corresponding optimal spectral band was established.The largest R^2 of relationship model between SSC and the average reflectance of associated optimal band reached to 0.95,and RMSEC and RMSEP were 1.076 and 0.591,respectively.Significant statistical analysis of salt fac-tors and soil reflectance for different microbial remediation processes indicated that the spectral response char-acteristics and sensitivity of SSC to soil reflectance,which implied the feasibility of high spectrum test on soil microbial remediation monitoring,also provided the basis for quick nondestructive monitoring soil bioremedi-ation process by soil spectral reflectance.