Department of Agronomy, Universidad de Córdoba, 14071, Córdoba, Spain.
Council for Agricultural Research and Economics, Research Centre for Agriculture and Environment, via della Navicella 2-4, 00184, Rome, Italy.
J Environ Manage. 2024 May;358:120772. doi: 10.1016/j.jenvman.2024.120772. Epub 2024 Apr 11.
Increasing soil organic carbon (SOC) content is crucial for soil fertility, conservation, and combating climate-related issues by sequestering CO. While existing studies explore the total content of SOC, few of them investigate the factors that favor its sequestration and the impact of land use type and management. This research aims to study the spatial variation of the total content and the quality or maturity (in terms of aromaticity) of the humic acid (HA) fraction, along with the factors that enhance its formation and conservation for a longer time in the soil. In addition, the study tries to evaluate the performance of the Regression Kriging (RK) method in producing interpolation maps that describe the natural variation of the SOC and its quality with the aim of defining and preventing soil degradation. Finally, the study aims to evaluate the impact of the land use type and the importance of dense vegetation in the sequestration of the organic carbon (OC) in the soil. The analysis of the SOC was performed in northeast Algeria's semi-arid climate, examining content, quality, and chemical composition. Using geostatistical methods (RK), SOC is correlated with most related factors, producing detailed interpolation maps. The results showed that the SOC and its HA fraction (both its total content and its degree of transformation or maturity (measured in terms of aromaticity and structural condensation) are highly correlated to the topography of the area (P < 0.05). Results reveal variations in HAs' composition across land covers. Notably, areas subjected to burning exhibited a 21% increase in HA aromaticity compared to forested regions and a 29% increase relative to cultivated areas. The study highlights that soil cover has a substantial influence on the performance of SOC sequestration, the forested areas have a positive impact on the storage of SOC in the form of HA with a more complex chemical composition that suggests increased aromaticity and resilience. As a whole, the results indicate the potential of geostatistical methods to provide valuable information about the factors that influence the current status and evolution of SOC in the study area.
增加土壤有机碳（SOC）含量对于土壤肥力、保护和通过固存 CO2 来应对与气候相关的问题至关重要。虽然现有研究探讨了 SOC 的总含量，但很少有研究探讨有利于其固存的因素以及土地利用类型和管理的影响。本研究旨在研究总含量和腐殖酸（HA）部分的质量或成熟度（芳香度方面）的空间变化，以及增强其在土壤中更长时间形成和保存的因素。此外，该研究试图评估回归克里金（RK）方法在生成插值图方面的表现，这些插值图描述了 SOC 及其质量的自然变化，目的是定义和防止土壤退化。最后，该研究旨在评估土地利用类型和密集植被对土壤中有机碳（OC）固存的影响。SOC 的分析是在阿尔及利亚东北部的半干旱气候下进行的，检验了含量、质量和化学组成。使用地统计方法（RK），SOC 与大多数相关因素相关联，生成详细的插值图。结果表明，SOC 及其 HA 部分（总含量及其转化程度或成熟度（芳香度和结构缩合度衡量）与该地区的地形高度相关（P<0.05）。结果揭示了 HA 组成在不同土地覆盖物之间的变化。值得注意的是，与森林地区相比，燃烧区的 HA 芳香度增加了 21%，与耕地相比，HA 芳香度增加了 29%。该研究强调，土壤覆盖对 SOC 固存性能有重大影响，森林地区对以 HA 形式储存 SOC 具有积极影响，其具有更复杂的化学组成，表明芳香度和弹性增加。总的来说，结果表明地统计方法有潜力提供有关影响研究区域 SOC 现状和演变的因素的有价值信息。
