西双版纳热带雨林土壤N_(2)O和CO_(2)排放对氮添加的响应  

Response of Soil N_(2)O and CO_(2) Emissions to Nitrogen Addition in Xishuangbanna Tropical Rain Forest

作　　者：洪思思 巩合德[1] 朱秀雯 宋清海[2,3] 张一平[2,3] 周文君[2,3,4] 张孝良 沙丽清 HONG Sisi;GONG Hede;ZHU Xiuwen;SONG Qinghai;ZHANG Yiping;ZHOU Wenjun;ZHANG Xiaoliang;SHA Liqing(School of Geography and Ecotourism,Southwest Forestry University,Kunming Yunnan 650224,P.R.China;CAS Key Laboratory of Tropical Forest Ecology,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,MenglaXishuangbanna 666303,P.R.China;Center for Plant Ecology,Core Botanical Gardens,Chinese Academy of Sciences,Mengla Xishuangbanna 666303,P.R.China;University of Chinese Academy of Sciences,Beijing 100049,P.R.China;Yunnan University,Kunming Yunnan 650091,P.R.China;Institutional Center for Shared Technologies and Facilities of Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Mengla Xishuangbanna 666303,P.R.China)

机构地区：[1]西南林业大学地理与生态旅游学院,云南昆明650224 [2]中国科学院西双版纳热带植物园热带森林生态学重点实验室,云南勐腊666303 [3]中国科学院核心植物园植物生态中心,云南勐腊666303 [4]中国科学院大学,北京100049 [5]云南大学,云南昆明650091 [6]中国科学院西双版纳热带植物园公共技术中心,云南勐腊666303

出　　处：《西部林业科学》2023年第3期118-127,共10页Journal of West China Forestry Science

基　　金：国家自然科学基金项目(42073080、31870467);云南省中青年学术和技术带头人后备人才项目(202205AC160045);云南省自然科学基金项目(2019IB018);云南省第四批博士后定向培养项目,中国科学院“一三五”专项(2017XTBG-F01、2017XTBG-T01);中国科学院战略性先导科技专项(XDA05020302)。

摘　　要：为探明未经干扰的热带雨林土壤N_(2)O与CO_(2)排放对氮沉降的响应,以西双版纳热带雨林为研究对象,设置了对照(CK)和氮添加处理(N),在持续16个月的连续观测期内,利用静态箱-气相色谱法连续观测土壤N_(2)O与CO_(2)通量,同步测定土壤含水量、土壤5 cm温度、土壤铵态氮与硝态氮含量,模拟氮沉降对未经干扰过的热带雨林土壤的N_(2)O与CO_(2)排放的影响。结果显示:与CK处理相比,N处理使西双版纳热带雨林土壤N_(2)O累积排放量增加24.06%,CO_(2)累积排放量增加10.98%;氮添加带来的增排效应主要集中在氮添加后4个月的显著响应期内,后续非显著响应期内N_(2)O与CO_(2)的增排效应并不显著(t=0.98,P>0.05);在全观测期中,土壤含水量、土壤5 cm温度与土壤N_(2)O、CO_(2)排放通量显著正相关(P<0.05),但是显著响应期内只有CK处理的土壤CO_(2)排放与土壤5 cm温度显著相关(P<0.05),其余均无显著相关关系(P>0.05);氮添加带来的热带雨林土壤N_(2)O和CO_(2)的增温潜势(GWP)相当于该生态系统的碳汇能力的103%和104%。研究结果表明,一次氮添加增加了未经干扰的热带雨林土壤的N_(2)O与CO_(2)排放,并改变了土壤碳氮排放与环境因子的关系,对区域气候变化形成正反馈效应。In order to explore the response of soil N_(2)O and CO_(2) emissions to nitrogen deposition in undisturbed tropical rain forest,this study took Xishuangbanna tropical rain forest as the research object,and set control(CK)and nitrogen addition treatment(N).During the continuous observation period lasting 16 months,static opaque chamber and gas chromatography was used to continuously observe soil N_(2)O and CO_(2) fluxes.Soil moisture content,soil temperature at 5 cm were detected synchronously,and contents of soil ammonium nitrogen and nitrate nitrogen contents were measured synchronously to simulate the effect of nitrogen deposition on the N_(2)O and CO_(2) emissions of undisturbed tropical rainforest soil.The results are following:Compared with CK treatment,N treatment increased soil N_(2)O emission by 24.06%and CO_(2) emission by 10.98%in Xishuangbanna tropical rain forest.The increase and emission effects of nitrogen addition were mainly concentrated in the significant response period of 4 months after nitrogen addition,while the increase and emission effects of N_(2)O and CO_(2) were not significant in the non-significant response period(t=0.98,P>0.05).In the whole observation period,soil water content and soil temperature at 5 cm were significantly positively correlated with soil N_(2)O and CO_(2) emission flux(P<0.05),but in the significant response period,only soil CO_(2) emission under CK treatment was significantly correlated with soil temperature at 5 cm(P<0.05),and the rest were not significantly correlated(P>0.05).The warming potential(GWP)of soil N_(2)O and CO_(2) in tropical rain forest caused by nitrogen addition is equivalent to 103%and 104%of the carbon sink capacity of the ecosystem.The results showed that one time single nitrogen addition increased the soil N_(2)O and CO_(2) emissions in undisturbed tropical rainforest soil,and changed the relationship between soil carbon and nitrogen flux emissions and environmental factors,and feedbacked to regional climate change positively.

关 键 词：氮添加 CO_(2)通量 N_(2)O通量 热带雨林土壤 GWP Q_(10) 

分 类 号：S714[农业科学—林学]