發(fā)布時間：2018-03-10 08:49

  本文選題：土壤有機(jī)質(zhì)　切入點：高光譜　出處：《光譜學(xué)與光譜分析》2017年11期 　論文類型：期刊論文

【摘要】：隨著近地高光譜遙感技術(shù)的發(fā)展,為快速、有效、非破壞性地獲取土壤有機(jī)質(zhì)(SOM)信息提供了可能。土壤高光譜波段數(shù)據(jù)眾多,光譜數(shù)據(jù)變量之間存在較為嚴(yán)重的多重共線性,影響模型復(fù)雜結(jié)構(gòu),而構(gòu)建歸一化光譜指數(shù)(NDSI)可以有效去除冗余信息變量,放大光譜特征信息。以江漢平原公安縣為研究區(qū),采集56份耕層土樣,在室內(nèi)獲取土壤光譜數(shù)據(jù),采用"重鉻酸鉀-外加熱法"測定SOM含量,對實測土壤光譜數(shù)據(jù)(Raw)進(jìn)行倒數(shù)之對數(shù)(LR)、一階微分(FDR)和連續(xù)統(tǒng)去除(CR)三種變換,計算四種變換的NDSI數(shù)值,分析SOM與NDSI的二維相關(guān)性,并對一維、二維相關(guān)系數(shù)進(jìn)行全波段范圍內(nèi)的p=0.001水平上顯著性檢驗,提取敏感波段和敏感光譜指數(shù),結(jié)合偏最小二乘回歸(PLSR)建立SOM的估算模型,探討二維光譜指數(shù)用于建模的可行性。研究表明,二維相關(guān)系數(shù)相比一維相關(guān)系數(shù)有不同程度的提升,以LR最為顯著,相關(guān)系數(shù)數(shù)值提升約0.26;基于二維相關(guān)性分析提取的敏感光譜指數(shù)的PLSR建模效果整體優(yōu)于一維相關(guān)性分析提取的敏感波段,其中,NDSILR-PLSR模型的穩(wěn)健性最優(yōu),驗證集R2為0.82,模型驗證RPD值為2.46,模型穩(wěn)定可靠,可以滿足SOM的精確監(jiān)測需要,適合推廣到區(qū)域范圍內(nèi)低分辨率的航空航天遙感(如ASTER,Landsat TM等),應(yīng)用潛力較大。
[Abstract]:With the development of near-ground hyperspectral remote sensing technology, it is possible to obtain soil organic matter SOM information quickly, effectively and nondestructive. The complex structure of the model is affected, and the normalized spectral index (NDSI) can be used to remove redundant information variables and enlarge spectral characteristic information effectively. Taking Gongan County in Jianghan Plain as the study area, 56 soil samples were collected and soil spectral data were obtained indoors. The SOM content was determined by "potassium dichromate plus calorimetry". The reciprocal logarithmic LRN, first-order differential SOM and continuum removal NDSI were used to calculate the NDSI values of the four transformations, and the two-dimensional correlation between SOM and NDSI was analyzed. The correlation coefficients of one and two dimensions were tested at the level of pn0. 001 in the whole band range. The sensitive band and sensitive spectral index were extracted, and the estimation model of SOM was established by combining with partial least squares regression. The feasibility of using two-dimensional spectral index in modeling is discussed. The results show that the two-dimensional correlation coefficient has different degrees of improvement compared with one-dimensional correlation coefficient, LR is the most significant. The correlation coefficient was increased by 0.26, and the PLSR model based on two-dimensional correlation analysis was better than that of one-dimensional correlation analysis, in which the robustness of NDSILR-PLSR model was optimal. The verification set R2 is 0.82and the model verification RPD value is 2.46. the model is stable and reliable, which can meet the needs of accurate monitoring of SOM. It is suitable for the application of low-resolution aerospace remote sensing (such as ASTER-Landsat TM, etc.) in the regional range, and has great application potential.
【作者單位】： 華中師范大學(xué)地理過程分析與模擬湖北省重點實驗室;華中師范大學(xué)城市與環(huán)境科學(xué)學(xué)院;
【基金】：國家自然科學(xué)基金項目(41401232,41271534) 中央高校基本科研業(yè)務(wù)費專項資金項目(CCNU15A05006,CCNU15A05004)資助
【分類號】：S153.621;TP79
，

本文編號：1592613