三峡库区马尾松林土壤铁、铝对有机碳的影响  

Effects of soil iron and aluminium on organic carbon in Pinus massoniana forests in the Three Gorges Reservoir area

作　　者：李一 林敦梅[1] 魏培 邹翠 赵洋 沈蓉 蔡肖凌 王尘辰 朱广宇 郭劲松[1] LI Yi;LIN Dun-mei;WEI Pei;ZOU Cui;ZHAO Yang;SHEN Rong;CAI Xiao-ling;WANG Chen-chen;ZHU Guang-yu;GUO Jin-song(Key Laboratory of Eco-Environment in Three Gorges Reservoir Area of Ministry of Education,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400044

出　　处：《中国环境科学》2024年第1期251-260,共10页China Environmental Science

基　　金：中国博士后科学基金资助项目(2020M683);长江上游生态环境问题基础性科学研究专项青年项目(02190052020066)。

摘　　要：为了解不同形态铁、铝矿物对土壤有机碳稳定的影响,以三峡库区典型土壤质地类型的马尾松林为研究对象,采用选择性溶解提取法测定晶质矿物(DH)、短程有序矿物(HH)和有机金属络合物(PP)中的铁、铝矿物及其结合有机碳的含量,并通过相关性分析和多元回归模型探讨了不同形态铁、铝矿物及其结合有机碳与土壤有机碳的相互关系.结果表明:不同形态铁、铝矿物含量分布为DH>PP>HH,且随土壤黏粒组分增加有明显的上升趋势.DH、PP和HH提取碳含量分别为(6.11±0.35)mg/g,(6.25±0.46)mg/g和(1.14±0.06)mg/g,分别占土壤有机碳的(32.06%±1.95%),(32.61%±2.33%)和(5.95%±0.33%).提取碳与金属物质的量比值(C:Fe+Al)表现为PP>DH≈HH,表明铁、铝矿物随结晶度的增加,与有机碳的结合方式从共沉淀和络合向吸附作用转变.提取碳含量与对应提取金属(Fe+Al)含量呈显著正相关(P<0.05),且提取铁、铝矿物是土壤有机碳变异性的第一解释变量(74.65%).总体而言,铁、铝矿物与有机碳的相互作用驱动了三峡库区马尾松林土壤有机碳的稳定累积,其中晶质铁、铝矿物和有机金属络合物起主导作用.To comprehensively understand the impact of various forms of iron(Fe)and aluminium(Al)minerals on soil organic carbon(SOC)stabilization,this study was conducted in the Pinus massoniana forest with typical soil textures in the Three Gorges Reservoir area.The contents of Fe and Al minerals in the crystalline minerals(DH),short-range order minerals(HH),and organo-metal complexes(PP),along with their associated organic carbon,were determined using a selective dissolution extraction method.The interrelationship between different forms of Fe,Al minerals,and their associated organic carbon with soil organic carbon was investigated through correlation analysis and multiple regression analysis.Key findings revealed:(1)varied Fe,Al mineral contents ranked DH>PP>HH,exhibiting a noticeable upward trend with increased clay content;(2)the organic carbon content extracted with DH,PP,and HH were(6.11±0.35)mg/g,(6.25±0.46)mg/g,and(1.14±0.06)mg/g,constituting approximately(32.06%±1.95%),(32.61%±2.33%),and(5.95%±0.33%)of SOC,respectively;(3)the carbon-to-metal(C:Fe+Al)molar ratio indicated PP>DH≈HH,suggesting a transition in the mineral-organic carbon interaction from co-precipitation and chelation toward adsorption with increased crystallinity;(4)extracted carbon content exhibited a positive correlation with the corresponding extracted metal(Fe+Al)(P<0.05),with Fe and Al minerals explaining 74.65%of the SOC variability as the primary explanatory variables.In summary,the interplay between organic carbon and Fe,Al minerals significantly influences SOC stabilization and storage in the soil of Pinus massoniana forests in the Three Gorges Reservoir area.Crystalline Fe,Al minerals,and organo-mineral complexes emerged as pivotal factors driving this phenomenon.

关 键 词：植被恢复 马尾松林 土壤 有机碳 铁、铝矿物 稳定机制 

分 类 号：X171[环境科学与工程—环境科学] S714.2[农业科学—林学]