宁夏旱区枸杞/覆盖作物种植体系对土壤活性有机碳库的影响  

Effects of cropping system of Lycium barbarum L.and cover crops on soil labile organic carbon pool in an arid region of Ningxia

作　　者：李文慧 陈浩楠 南雄雄 林妍敏 王芳[1,2,3] LI Wenhui;CHEN Haonan;NAN Xiongxiong;LIN Yanmin;WANG Fang(School of Geography and Planning,Ningxia University,Yinchuan 750021,China;China-Arab Joint International Research Laboratory for Featured Resources and Environmental Governance in Arid Regions,Yinchuan 750021,China;National Key Laboratory of Efficient Production of Forest Resources,Yinchuan 750004,China)

机构地区：[1]宁夏大学地理科学与规划学院,银川750021 [2]教育部中阿旱区特色资源与环境治理国际合作联合实验室,银川750021 [3]林木资源高效生产全国重点实验室,银川750004

出　　处：《生态学杂志》2024年第5期1324-1332,共9页Chinese Journal of Ecology

基　　金：宁夏自然科学基金项目(2022AAC03024);国家自然科学基金项目(42067022,41761066);研究生课程思政示范课建设项目(KCSZ202203)资助。

摘　　要：为探究种植覆盖作物和施用有机肥对宁夏旱区枸杞园土壤活性有机碳库的影响,通过田间定位试验,设置枸杞单作+不施有机肥(S_(0))、枸杞单作+中量有机肥(2 kg·株^(-1),S_(1))、枸杞单作+高量有机肥(4 kg·株^(-1),S_(2))、枸杞/肥田萝卜复合种植+不施有机肥(M_(0))、枸杞/肥田萝卜复合种植+中量有机肥(2 kg·株^(-1),M_(1))和枸杞/肥田萝卜复合种植+高量有机肥(4 kg·株^(-1),M_(2))6个处理,分析土壤有机碳活性组分含量、土壤碳库管理指数及其与其他理化因子的关系,并通过结构方程模型揭示驱动碳库管理指数变化的主要因素。结果表明:与传统枸杞单作相比,枸杞/肥田萝卜复合种植0~20 cm土层土壤易氧化有机碳、水溶性有机碳含量和微生物生物量碳显著提高了55.3%、25.2%和79.0%,同时碳库活度、碳库活度指数和碳库管理指数也显著提高了18.4%、26.8%和18.4%(P<0.05)。而20~40 cm土层土壤有机碳组分及碳库管理指数变化均不显著。与未施用有机肥处理相比,中量有机肥处理0~20 cm土层S1和M1处理的碳库活度和碳库活度指数显著提高,高量有机肥处理仅M2处理的碳库活度、碳库活度指数和碳库管理指数显著提高61.9%、59.4%和64.9%(P<0.05)。而20~40 cm土层S_(1)和S_(2)处理的碳库指数显著降低,M_(1)和M_(2)处理的有机碳组分和碳库管理指数变化均不显著。结构方程模型显示:有机碳、易氧化有机碳、水溶性有机碳、全氮含量和微生物生物量碳共同解释了碳库管理指数98%的变化。综上所述,宁夏旱区枸杞/覆盖作物复合种植模式能有效提升土壤活性有机碳含量,在减少有机肥施用量的情况下仍能达到土壤培肥的目的。This study aimed to understand the effects of cover cropping and organic fertilization on soil labile organic carbon pool in Goji(Lycium barbarum L.)fields in an arid region of Ningxia.There were six treatments,including L.barbarum monocropping+no fertilization(S_(0)),L.barbarum monocropping+medium-level organic fertilization(2 kg·plant^(-1),S_(1)),L.barbarum monocropping+high-level organic fertilization(4 kg·plant^(-1),S_(2)),L.barbarum/radish(Raphanus sativus L.)intercropping+no fertilization(M_(0)),L.barbarum/R.sativus intercropping+medium-level organic fertilization(2 kg·plant^(-1),M_(1)),and L.barbarum/R.sativus intercropping+high-level organic fertilization(4 kg·plant^(-1),M_(2)).We measured the contents of soil labile organic carbon fractions,carbon pool management index,and analyzed the relationships between carbon pool management index and other physicochemical factors.The main factors driving variation in carbon pool management index were identified by structural equation model.The results showed that compared with the traditional L.barbarum monocropping,L.barbarum/R.sativus intercropping increased readily oxidizable organic carbon content,dissolved organic carbon content,and microbial biomass carbon(by 55.3%,25.2%,and 79.0%,respectively),as well as in carbon lability,carbon lability index,and carbon pool management index(by 18.4%,26.8%,and 18.4%,respectively)in the 0-20 cm soil layer(P<0.05).There were no significant changes in the contents of organic carbon fractions and carbon pool management index in the 20-40 cm soil layer.Compared with no organic fertilization,carbon lability and carbon lability index of 0-20 cm soil layer significantly increased in the S_(1) and M_(1) treatments with medium-level organic fertilization.Under high-level organic fertilization,the carbon lability,carbon lability index,and carbon pool management index of 0-20 cm soil layer significantly increased in the M_(2) treatment only,by 61.9%,59.4%,and 64.9%,respectively(P<0.05).In the 20-40 cm soil layer,the carbon pool in

关 键 词：覆盖作物 有机碳组分 活性碳库 碳库管理指数 结构方程模型 

分 类 号：S153.6[农业科学—土壤学]