不同围垦年限滨海垦区盐渍土碳库及团聚体稳定性变化特征  

Characteristics of changes in carbon pools and aggregate stability of coastal reclaimed saline-alkali soil

作　　者：路迅 勾泽清 王涛 董天望 朱倩倩 左希爱 徐璐 李建国 Lu Xun;Gou Zeqing;Wang Tao;Dong Tianwang;Zhu Qianqian;Zuo Xiai;Xu Lu;Li Jianguo(School of Geography,Geomatics and Planning,Jiangsu Normal University,Xuzhou,Jiangsu 221116,China)

机构地区：[1]江苏师范大学地理测绘与城乡规划学院,江苏徐州221116

出　　处：《水土保持研究》2025年第2期111-121,139,共12页Research of Soil and Water Conservation

基　　金：国家自然科学基金(42271287,42371053);江苏省碳达峰与碳中和技术创新专项资金(BE2023855);江苏师范大学研究生科研与实践创新计划项目(2024XKT0148)。

摘　　要：[目的]探究滨海盐渍土随着围垦年限增加变化特征,为滨海盐渍土治理提供理论依据。[方法]选取江苏省盐城市大丰区不同围垦时期田地,以围垦0 a(Y_(1))、20 a左右(Y_(2))、40 a左右(Y_(3))、60 a左右(Y_(4))、100 a左右(Y5)下滨海表层(0—20 cm)、亚表层(20—40 cm)盐渍土中各有机碳组分、碳库指标、团聚体稳定性指标为研究对象,研究了其随不同围垦时期变化特征及影响因素。[结果](1)表层土壤中各活性有机碳组分及亚表层土壤HLOC(高活性有机碳)、LOC(活性有机碳)基本呈现先增加后降低趋势,拐点在Y_(4)处,其中亚表层土壤中MLOC(中活性有机碳)未随围垦年限增加而出现显著性变化,LLOC(低活性有机碳)呈现先增加后稳定趋势,拐点在Y_(3)处。(2)随着围垦年限增加,表层土壤R_(0.25)(>0.25 mm团聚体含量)、GWD(几何平均直径)与亚表层土壤MWD(平均重量直径)呈现先上升后降低趋势,表层土壤MWD呈现先上升后稳定趋势,拐点均在Y_(4)处;亚表层土壤R_(0.25),GWD呈现下降—增加—下降趋势,拐点分别在Y_(2),Y_(4)处。(3)相关性分析表明,表层土壤中,RY(围垦年限)对团聚体稳定性指标均起到重要促进作用,除NO_(3)^(-)和Ca^(2+)外其他离子,EC(电导率),SAR(钠吸附比),UW(容重),pH值均对团聚体稳定性起到重要阻碍作用;亚表层土壤中,UW,除NO_(3)^(-)和Ca^(2+)外其他离子,EC,SAR是破坏团聚体稳定性的主要因素。(4)除亚表层土壤中A(碳库活度),AI(碳库活度指数),团聚体稳定性指标是促进表层和亚表层土壤碳库增加的主要影响因素,除NO_(3)^(-)和Ca^(2+)外其他离子,EC,UW是阻碍碳库增加主要影响因素。[结论]围垦活动降低了土滨海盐渍土表层和亚表层壤盐分离子含量,提高了大团聚体含量、团聚体稳定性、不同活性有机碳组分含量、碳库相关指标,但大于60 a围垦需注意土地退化。[Objective]The aims of this study are to explore the characteristics of changes in coastal saline soil with increasing years of reclamation,and to provide theoretical basis for the treatment of coastal saline soil.[Methods]Field plots in different reclamation periods in Dafeng District,Yancheng City,Jiangsu Province were selected.Organic carbon components,carbon pool indicators,and aggregate stability indicators in coastal surface(0—20 cm)and sub-surface(20—40 cm)saline soils reclaimed for 0 years(Y_(1)),around 20 years(Y_(2)),around 40 years(Y_(3)),around 60 years(Y_(4)),and around 100 years(Y 5)were investigated to explore their characteristics and influencing factors under different reclamation periods.[Results](1)Various active organic carbon components in the surface soil and HLOC(highly labile organic carbon)in the subsoil generally showed an increasing and then decreasing trend,with a turning point at Y_(4).Among them,in the subsoil,MLOC(moderately labile organic carbon)did not show significant changes with increasing reclamation years,while LLOC(low labile organic carbon)showed an increasing and then stable trend,with a turning point at Y_(3).(2)With the increase in reclamation years,the surface soil R_(0.25)(>0.25 mm aggregate content)and GWD(geometric mean diameter),as well as the subsurface soil MWD(mean weight diameter),exhibited a trend of first rising and then declining,with a turning point at Y_(4).The surface soil MWD showed a trend of rising initially and then stabilizing,with its turning point also at Y_(4).The subsurface soil R_(0.25) and GWD showed a decrease-increase-decrease trend,with turning points at Y_(2) and Y_(4),respectively.(3)Correlation analysis showed that in the surface soil,RY(reclamation years)played an important promoting role in aggregate stability indicators,while other ions except NO_(3)^(-) and Ca^(2+),EC(electrical conductivity),SAR(sodium adsorption ratio),UW(bulk density),and pH value played important hindering roles in aggregate stability.In the subsoil,UW,other io

关 键 词：滨海盐渍土 围垦年限 团聚体 碳库 

分 类 号：S151.9[农业科学—土壤学] S156[农业科学—农业基础科学]