3D soil void space lacunarity as an index of degradation after land use change

ABSTRACT. In this work, lacunarity analysis is performed on soil pores segmented by the pure voxel extraction method from soil tomography images. The conversion of forest to sugarcane plantation was found to result in higher sugarcane soil pore lacunarity than that of native forest soil, while the porosity was found to be lower. More precisely, this study shows that native forest has more porous soil with a more uniform spatial distribution of pores, while sugarcane soil has lower porosity and a more heterogeneous pore distribution. Moreover, validation through multivariate statistics demonstrates that lacunarity can be considered a relevant index of clustering and can explain the variability among soils under different land use systems. While porosity by itself represents a fundamental concept for quantification of the impact of land use change, the current findings demonstrate that the spatial distribution of pores also plays an important role and that pore lacunarity can be adopted as a complementary tool in studies directed at quantifying the effect of human intervention on soils.

摘要。本研究针对土壤断层扫描图像中经纯体素提取法分割得到的土壤孔隙开展间隙度（lacunarity）分析。研究发现，林地转为甘蔗种植园后，其土壤孔隙间隙度高于原生林土壤，而孔隙度则更低。具体而言，本研究表明原生林土壤孔隙更为发育，且孔隙空间分布更为均匀；甘蔗种植园土壤则孔隙度更低，孔隙分布也更为不均一。此外，通过多元统计分析验证可知，间隙度可被视为表征孔隙聚集特征的有效指标，能够解释不同土地利用系统下土壤间的差异。尽管孔隙度本身是量化土地利用变化影响的核心概念，但本研究结果显示，孔隙的空间分布同样发挥着重要作用，且孔隙间隙度可作为补充工具，应用于量化人类活动对土壤影响的相关研究中。