放牧对滇西北高原纳帕海沼泽化草甸湿地土壤氮转化的影响  

Effects of grazing on nitrogen transformation in swamp meadow wetland soils in Napahai of Northwest Yunnan

作　　者：王雪[1] 郭雪莲[1] 郑荣波 王山峰[1] 刘双圆 田伟 WANG Xue;GUO Xuelian;ZHENG Rongbo;WANG Shanfeng;LIU Shuangyuan;TIAN Wei(National Plateau Wetland Research Center, Southwest Forestry University, Kunming 650224, China;Faculty of Chemical Engineering, Southwest Forestry University, Kunming 650224, China;Napa Lake Wetland Management Bureau in Shangri-La City, Diqing 674400, China)

机构地区：[1]西南林业大学国家高原湿地研究中心,昆明650224 [2]西南林业大学化学工程学院,昆明650224 [3]云南香格里拉市纳帕海湿地管理局,迪庆674400

出　　处：《生态学报》2018年第7期2308-2314,共7页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(41563008;41001332);云南纳帕海国际重要湿地2015年生态效益补偿试点项目

摘　　要：选择位于滇西北高原纳帕海国际重要湿地内的典型沼泽化草甸湿地为研究对象,采用原位土柱室内控制实验法研究了放牧干扰(猪翻拱扰动和牲畜践踏)对沼泽化草甸湿地土壤氮转化的影响。研究结果表明,放牧活动显著提高了沼泽化草甸湿地表层土壤的容重和pH值,降低了土壤含水率、TOC、TN和NH_4^+-N含量,而对NO_3^--N含量影响不显著。放牧干扰下沼泽化草甸湿地土壤的矿化速率和硝化速率均表现为猪翻拱扰动样地(ZG)>牲畜践踏样地(JT)>对照样地(CK);表现为ZG>JT>CK。放牧干扰促进了沼泽化草甸湿地土壤的矿化和硝化作用,猪的翻拱活动比牲畜践踏活动对土壤氮矿化和硝化作用的促进作用更显著。放牧干扰下沼泽化草甸湿地土壤的反硝化速率表现为ZG>CK>JT,猪的翻拱活动促进了土壤N_2O气体的排放,而牲畜践踏活动抑制了土壤N_2O气体的排放。相关性分析表明,受放牧干扰的沼泽化草甸湿地土壤的矿化和硝化速率均与土壤容重、pH呈显著正相关,与土壤含水率、NH_4^+-N、TOC、TN含量呈显著负相关;反硝化速率与TOC含量呈显著负相关。In this study, the typical swamp meadow wetland in Napahai, a Wetland of International Importance, in Northwest Yunnan was selected as the research site. Nitrogen transformations in swamp meadow wetland soils under the influence of grazing disturbance were measured and analyzed using in situ column interior control experiment methods. The results showed that the soil bulk density and pH were increased, and the soil moisture content, total organic carbon content, total nitrogen content, and NH4^＋-N content were decreased in surface soils with grazing disturbance. The mineralization and nitrification rates of swamp meadow wetland soils with the influence of grazing disturbance showed a significant decrease：pig arch 〉 cattle-trampled 〉 control. Both pig arch and cattle-trampled sites enhanced the mineralization and nitrification rates. Denitrification rates of swamp meadow wetland soils with the influence of grazing disturbance showed a significant decrease：pig arch 〉 control 〉 cattle-trampled （P 〈 0.05）. Pig arch sites promoted N2O release but cattle-trampled sites inhibited N2O release. In contrast, both the mineralization and nitrification rates of swamp meadow wetland soils with the grazing disturbance had a significant positive correlation with soil bulk density and pH, and a significant negative correlation with soil moisture content, NH4^＋-N content, TOC, and TN. Denitrification rate had a significant negative correlation with TOC.

关 键 词：纳帕海 放牧干扰 矿化作用 硝化作用 反硝化作用 

分 类 号：S812.2[农业科学—草业科学]