贵州喀斯特山区典型土壤氧化铁特征及其与土壤类型分异关系  

Characteristics of Iron Oxides and their Relationship with Soil Types in the Karst Mountainous Areas of Guizhou

作　　者：刘玉晶 陆晓辉[1] 罗丹 张巧灵 尹梅红 蒋佳敏 段兴林 LIU Yu-jing;LU Xiao-hui;LUO Dan;ZHANG Qiao-ling;YIN Mei-hong;JIANG Jia-min;DUAN Xing-lin(State Key Laboratory Incubation Base for Karst Mountain Ecology Environment of Guizhou Provence,College of geography and Environmental Sciences,Guizhou Normal University,Guiyang 550025,China)

机构地区：[1]贵州师范大学地理与环境科学学院/贵州省喀斯特山地生态环境国家重点实验室培育基地,贵州贵阳550025

出　　处：《土壤通报》2021年第3期505-514,共10页Chinese Journal of Soil Science

基　　金：国家自然科学基金项目(41867001、41261058);贵州师范大学学术新苗培养及创新探索专项项目(黔科合平台人才[2018]5769-23);贵州师范大学博士科研项目(GZNUD[2017]7号)资助。

摘　　要：以贵州省喀斯特山区30个典型土壤剖面为研究对象,采集土样,测定不同形态的氧化铁含量、计算相应的风化度指标,通过分析不同形态氧化铁含量、风化度指标与土壤类型分异的关系,探讨了氧化铁特征对喀斯特山区典型土壤类型分异的指示作用。结果表明:游离氧化铁是区内土壤氧化铁的主要存在形态(26.62~75.99 g kg^(-1));绝大部分土壤的铁活化度<30%,游离度≥50%,游离氧化铁≥30 g kg^(-1),均处于中期脱硅富铝化阶段;土壤络合态氧化铁及络合度具有较强的空间异质性。按中国土壤发生学分类土壤(亚类)的氧化铁特征,各石灰土亚类不同形态氧化铁含量及其风化度指标(除非晶质氧化铁和络合度外)均存在显著性差异(P<0.05);随着晶质态氧化铁含量及游离度、晶化度增加和活化度减少,土壤风化程度逐渐增加,土壤类型有由棕色石灰土到黄色石灰土再到红色石灰土的演化趋势。按中国土壤系统分类土壤(土纲、土类)的氧化铁特征,各土纲、土类不同形态氧化铁含量及其风化度指标(除晶化度外)均有较大差异;随着晶质态氧化铁含量及游离度、晶胶率增加和活化度减少,土壤风化发育程度逐渐加深,存在由淋溶土土纲向富铁土土纲转变、由钙质湿润淋溶土土类到铁质湿润淋溶土土类的演变趋势。Taking 30 typical soil profiles in the karst mountainous areas of Guizhou as the research object,this paper collected soil samples,measured the contents of different forms of iron oxide,calculated the corresponding weathering index,analyzed the relationship between the contents of different forms of iron oxide,weathering index and the differentiation of soil types,and discussed the indicative effect of iron oxide characteristics on the differentiation of typical soil types in the karst mountainous areas.The results showed that free iron oxide was its main form in the soil(26.62-75.99 g kg^(-1)).Most of the soil samples had the iron activity degree<30%,free degree≥50%,and free iron oxide≥30 g kg^(-1) in the middle stage of desilication and aluminum enrichment.The complex iron oxide and complexation degree of soil showed a strong spatial heterogeneity.There were significant differences(P<0.05)in iron oxide form and weathering index(except crystalline iron oxide and degree of complexation)among different types of Calcareous soil based on the Chinese soil genesis classification.With the increase of crystalline iron oxide,crystallized degree and free degree,the activity degree was decreased,and the weathering degree of soil was increased gradually.The evolution of soil types was from Brown Lime soil to Yellow Lime soil and then to Red Lime soil.In the Chinese soil taxonomy(soil order,soil group),the iron oxide forms and weathering index(except crystallinity)were quite different among soil classes,subgroups and groups.With the increase of crystalline iron oxide,free degree and crystal gel rate,the activity degree was decreased,and the weathering degree of soil was gradually deepened.There was an evolution trend of soil class from leaching soil to iron rich soil and from calcareous soil to iron wet leaching soil.

关 键 词：氧化铁 石灰土 系统分类 发生分类 

分 类 号：S155.1[农业科学—土壤学]