Benslama Abderraouf, Benbrahim Fouzi, Rym-Gadoum Lydia, Gómez-Lucas Ignacio, Mordan-Vidal Manuel Miguel, Navarro-Pedreño Jose, Bech-Borrás Jaume
Laboratory of Valuation and Conservation of Arid Ecosystems (LVCEA), Department of Biology, Faculty of Sciences Natural and Life, Earth and Universe Sciences, University of Ghardaïa, BP455, 47000, Bounoura, Ghardaïa, Algeria.
Department of Agrochemistry and Environment, University Miguel Hernández of Elche, 03202, Elche, Spain.
Environ Geochem Health. 2024 Jul 17;46(9):330. doi: 10.1007/s10653-024-02036-w.
This study aims to assess the amount of organic carbon stored in soils, as it is an intention of knowing the sustainable soil management, by using two common methods for determining soil organic matter (SOM), namely oxidation with acidified wet dichromate (Walkley-Black method-WB) and loss on ignition (LOI). The study was carried with soil samples collected from a depth of 0 to 30 cm in the Saharan arid region of Ghardaïa (Algeria), with different land uses: agricultural, forest and pastoral. The results obtained from the LOI and WB methods were subjected to statistical analysis, and the relations between both methods were tested to investigate their relationship. The mean percentage of SOM values were 1.86, 2.42, 1.54 by using LOI, but, lower values of 0.34, 0.33, 0.36 were determined by using WB method, for agricultural, forest and pastoral soils respectively. A weak linear relationship between the two analytical procedures was obtained (R of 0.19 and 0.13 for agricultural and forest soils), while a medium relationship (R = 0.65) was found for pastoral soils when using linear adjustment. However, the opposite behaviour was found when we use the logarithmic adjustment. The study outcomes indicated discrepancies in the measurements of SOM values between the two methods, been higher those estimated with LOI. Finally, in order to identify the best methodology to measure soil organic matter in arid soils, more research is required in these extreme arid regions as they are a gap in world soil organic matter maps.
本研究旨在评估土壤中有机碳的储存量，因为了解可持续土壤管理的目的之一是通过使用两种常见的测定土壤有机质（SOM）的方法，即酸化湿重铬酸钾氧化法（沃克利 - 布莱克法 - WB）和烧失量法（LOI）。该研究采用了从阿尔及利亚加尔达亚撒哈拉干旱地区0至30厘米深度采集的土壤样本，这些土壤具有不同的土地利用方式：农业用地、林地和牧场。对LOI法和WB法获得的结果进行了统计分析，并测试了两种方法之间的关系以研究它们的相关性。使用LOI法时，农业、森林和牧场土壤的SOM值平均百分比分别为1.86、2.42、1.54，但使用WB法测定的值较低，分别为0.34、0.33、0.36。两种分析方法之间获得了较弱的线性关系（农业和森林土壤的R分别为0.19和0.13），而在牧场土壤中使用线性调整时发现了中等关系（R = 0.65）。然而，当我们使用对数调整时发现了相反的情况。研究结果表明，两种方法在SOM值测量上存在差异，LOI法估计的值更高。最后，为了确定在干旱土壤中测量土壤有机质的最佳方法，在这些极端干旱地区需要进行更多研究，因为它们在世界土壤有机质地图中存在空白。
