柑橘园覆盖光叶苕子促进土壤颗粒有机碳净积累  

Smooth-Vetch Cover Promotes the Net Accumulation of Soil Particulate Organic Carbon of Citrus Orchards

作　　者：张佳佳 肖文发[1,2,3] 雷蕾 杨鑫 胡建文[1] 杨洪炳 廖倚凌 曾立雄 Zhang Jiajia;Xiao Wenfa;Lei Lei;Yang Xin;Hu Jianwen;Yang Hongbing;Liao Yiling;Zeng Lixiong(Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Institute of Forest Ecology,Environment and Nature Conservation,CAF Beijing 100091;Co-Innovation Center for Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing 210037;Three Gorges Reservoir National Forest Ecosystem Observation and Research Station,Zigui 443600)

机构地区：[1]中国林业科学研究院森林生态环境与自然保护研究所国家林业和草原局森林生态环境重点实验室,北京100091 [2]南京林业大学南方现代林业协同创新中心,南京210037 [3]湖北秭归三峡库区森林生态系统国家定位观测研究站,秭归443600

出　　处：《林业科学》2025年第2期74-84,共11页Scientia Silvae Sinicae

基　　金：国家自然基金重点项目(32130074);中央级公益性科研院所基本科研业务费专项资金项目(CAFYBB2022XD001)。

摘　　要：【目的】明确在绿肥生长和自然腐解阶段,柑橘树根际和非根际土壤有机碳组分变化及其主要影响因素,以期更好地理解绿肥覆盖对果园土壤碳组分的作用机制,为推广果园绿肥覆盖措施提供科学依据。【方法】以光叶苕子覆盖的柑橘园为研究对象,以清耕处理为对照,在光叶苕子生长和自然腐解季节,探索柑橘根际和非根际土颗粒有机碳(包含游离态颗粒有机碳和闭蓄态颗粒有机碳)及矿物结合有机碳的分布,并分析土壤有机碳组分变化与植物特征(柑橘细根碳氮磷含量、苕子地上和细根年碳氮磷输入量)和土壤因子(游离态颗粒有机氮、闭蓄态颗粒有机氮、矿物结合有机氮、全氮、全磷、黏粒含量及胞外酶活性)的关系。【结果】与清耕对比,在苕子生长和腐解季节,绿肥覆盖均显著(P<0.05)增加了根际土(34.13%、56.01%)和非根际土的闭蓄态颗粒有机碳含量(33.02%和64.23%);均显著(P<0.05)降低了根际土(-12.56%、-19.72%)和非根际土的矿物结合有机碳含量(-13.10%、-20.67%)。游离态颗粒有机碳含量在苕子生长季节的非根际土显著增加(78.77%,P<0.05),而根际土降低(-8.48%,P<0.05),但在苕子腐解季节相反,表现为非根际土降低(-18.66%,P<0.05)、根际土增加(18.62%,P<0.05)。冗余分析表明,在光叶苕子覆盖下的柑橘园,土壤的游离态颗粒有机碳和闭蓄态颗粒有机碳含量与苕子细根的年碳氮输入量、土壤闭蓄态颗粒有机氮含量、全氮含量及黏粒含量显著(P<0.05)正相关,土壤矿物结合有机氮含量与矿物结合有机碳含量显著(P<0.05)正相关。方差分析表明,光叶苕子覆盖提高了植物与土壤因子对土壤有机碳组分的共同作用(从18.3%增加到33.9%)。层次分割进一步确定,矿物结合有机氮是降低土壤矿物结合有机碳含量的主要因素,闭蓄态颗粒有机氮、苕子细根的年碳氮输入量、土壤黏粒含量是影响土壤游离态颗�【Objective】This study aims to clarify the changes in soil organic carbon components and the main influencing factors in both the rhizosphere and non-rhizosphere soils of citrus trees during the growth and natural decomposition seasons of green manure.The goal is to gain a better understanding of the mechanisms by which green manure cover affects soil carbon components in orchards,providing scientific evidence to support the promotion of green manure practices in orchard management.【Method】Citrus orchards with and without smooth vetch cover(clean tillage treatment)were selected to measure the distribution of the particulate organic carbon,including free particulate organic carbon and occluded particulate organic carbon,as well as mineral-associated organic carbon in the rhizosphere and non-rhizosphere soils during the growth and decomposition seasons of the vetch.And the relationship between soil organic carbon components and plant characteristics(including the carbon,nitrogen,and phosphorus content of citrus fine roots,as well as annual carbon,nitrogen,and phosphorus input by vetch aboveground and fine root)and edaphic variables(free particulate organic nitrogen,occluded particulate organic nitrogen,mineral-associated organic nitrogen,total nitrogen,total phosphorus,clay content,and extracellular enzyme activity)were also analyzed.【Result】Compared to clear tillage,vetch cover significantly increased(P<0.05)the occluded particulate organic carbon content in both rhizosphere(34.13%and 56.01%,respectively)and non-rhizosphere soils(33.02%and 64.23%,respectively)during the vetch growth and decomposition seasons.However,vetch cover also significantly decreased(P<0.05)mineral-associated organic carbon content in both rhizosphere(−12.56%and−19.72%,respectively)and non-rhizosphere soils(−13.10%and−20.67%,respectively)during the both seasons.During vetch growth season,free particulate organic carbon content was significantly increased(P<0.05)in non-rhizosphere soils(78.77%)but decreased in rhizosphere s

关 键 词：三峡库区 光叶苕子覆盖 生长季节 自然腐解季节 土壤有机碳组分 

分 类 号：S154.1[农业科学—土壤学] S551.2[农业科学—农业基础科学]