Universidade Federal de Viçosa, Departamento de Solos, Av. PH Rolfs, s/n, Campus Universitário, 36570-000 Viçosa, MG, Brazil.
Universidade Federal do Rio Grande do Norte, Departamento de Geografia, Centro de Ensino Superior do Seridó, Rua Joaquim Gregório, s/n, Penedo, 59300-000 Caicó, RN, Brazil.
An Acad Bras Cienc. 2022 Feb 11;94(suppl 1):e20210625. doi: 10.1590/0001-3765202120210625. eCollection 2022.
Sulfurization is a pedogenic process that involves pyrite oxidation and strong soil acidification, accounting for the formation of acid sulfate soils. In Antarctica, acid sulfate soils are related to specific parent materials, such as sulfide-bearing andesites in Maritime Antarctica and pyritized sedimentary rocks in James Ross Archipelago. The hypothesis is that the acid sulfate soils of these regions vary according with a climate gradient. The reviewing of current data showed that the acid sulfate soils of warmer and wetter Maritime Antarctica have a greater weathering degree, higher acidity, leaching, phosphorus adsorption capacity, structural development, and well-crystallized iron oxides and kaolinite formation. On the other hand, the sulfurization at the drier region of James Ross Archipelago is counterbalanced by the semiaridity, resulting in lower acidity and higher base contents combined with little morphological and mineralogical evolution besides presence of weatherable minerals in the clay fraction. The sulfurization process interplays with other pedogenic processes, such as the phosphatization in Maritime Antarctica and salinization in James Ross Archipelago. Higher temperatures and soil moisture enhance the pedogenesis, showing that even the Antarctic sulfate soils, which originated from specific parent materials, have their development and characteristics controlled by a clear climatic gradient.
硫化作用是一种成土过程，涉及黄铁矿氧化和土壤强烈酸化，是形成酸性硫酸盐土壤的原因。在南极洲，酸性硫酸盐土壤与特定的母质有关，如马里亚纳南极洲的含硫化物安山岩和詹姆斯·罗斯岛群的含黄铁矿的沉积岩。假设这些地区的酸性硫酸盐土壤随气候梯度而变化。对现有数据的审查表明，温暖湿润的马里亚纳南极洲的酸性硫酸盐土壤具有更高的风化程度、更高的酸度、淋溶、磷吸附能力、结构发育以及结晶良好的氧化铁和高岭石的形成。另一方面，詹姆斯·罗斯岛群干燥地区的硫化作用被半干旱所抵消，导致酸度较低，碱含量较高，除了粘粒部分存在可风化的矿物外，形态和矿物演化也较少。硫化作用过程与其他成土过程相互作用，如马里亚纳南极洲的磷石化作用和詹姆斯·罗斯岛群的盐化作用。较高的温度和土壤湿度促进了成土作用，表明即使是源自特定母质的南极硫酸盐土壤，其发育和特征也受到明显气候梯度的控制。
