黄河口不同恢复阶段湿地土壤N_2O产生过程对氮输入的响应  

Effects of exogenous nitrogen on N_2O production processes in wetland soils of different restoration phases in the Yellow River estuary

作　　者：孙志高[1] 孙文广[2] 

机构地区：[1]福建师范大学地理研究所/湿润亚热带生态地理过程教育部重点实验室,福州350007 [2]路易斯安那州立大学植物、环境与土壤科学系,巴图鲁日70803

出　　处：《应用生态学报》2016年第4期1135-1144,共10页Chinese Journal of Applied Ecology

基　　金：国家自然基金面上项目(41371104,41171424);福建省“闽江学者奖励计划”项目和福建省高等学校“新世纪优秀人才计划”项目资助~~

摘　　要：以黄河口生态恢复前后未恢复区(R_0)、2007年恢复区(R_(2007))和2002年恢复区(R_(2002))的芦苇湿地为研究对象,研究了不同形态氮输入对湿地土壤N_2O产生过程的影响与贡献.结果表明:硝态氮(NO_3^--N)输入对恢复区湿地土壤N_2O总产生量的影响远远大于铵态氮(NH_4^+-N),但两者均抑制了R_0土壤的N_2O总产生量.尽管NO_3^--N输入对R_(2002)表层土壤N_2O总产生量的影响明显大于R_(2007),但二者的N_2O产生量均随氮输入量的增加而增加.恢复区湿地土壤的反硝化作用和硝化细菌反硝化作用受NO_3^--N输入的影响明显,而R_0土壤产生N_2O的生物过程受其影响并不显著.尽管NH_4^+-N输入对湿地土壤N_2O的总产生量影响不大,但其输入整体促进了R_0土壤的硝化细菌反硝化作用、R_(2007)土壤的硝化作用和R_(2002)土壤的非生物作用.比较而言,NO_3^--N输入对R_0、R_(2007)和R_(2002)湿地土壤N_2O产生的非生物作用主要表现为抑制,NH_4^+-N输入则整体提高了R_0和R_(2002)湿地土壤非生物作用的N_2O产生量,这与不同形态氮输入对土壤p H的调节作用密切相关.研究发现,NO_3^--N输入大大增加了湿地土壤的N_2O总产生量,改变了原有湿地土壤生物作用和非生物作用的贡献模式,故生态恢复工程导致的营养盐输入(NO_3^--N)应受到特别关注.The effects of exogenous nitrogen on N_2O production processes in the soils of un-restoration wetland（ R_0）,restoration wetland since 2007（ R_（2007）） and restoration wetland since 2002（ R_（2002）） of the Yellow River estuary were studied,and the contributions of different processes in N_2O production were determined.Results showed that the N_2O production of restoration wetland soils（ R_（2002） and R_（2007）） with NO_3^--N addition was much higher than that with NH_4^＋-N addition,but both NH_4^＋-N and NO_3^--N additions demonstrated inhibition on the N_2O production of soils in R_0.Although the effect of NO_3^--N addition on the total N_2O production of topsoil in R_（2002） was significantly higher than those in R_（2007）,the values in R_（2002） and R_（2007）were greatly increased with increasing NO_3^--N addition.The denitrification and nitrifier denitrification processes in restoration wetland soils（ R_（2002） and R_（2007）） were greatly affected by NO_3^--N addition,but no significant influence on the non-biological processes of soil in R_0 was observed.Although NH_4^＋-N addition did not produce significant effects on the total N_2O production of wetland soils,the nitrifier denitrification process in R_0 soil,the nitrification process in R_（2007） soil and the non-biological process in R_（2002） soil were generally stimulated.In R_0 and R_（2002）soils,the N_2O produced by non-biological processes was generally eleva-ted with NH_4^＋-N addition,while with NO_3^--N addition,the non-biological processes generating N_2O in R_0,R_（2002） and R_（2007）soils were generally inhibited,which was closely correlated with the regulation of soil p H caused by the import of exogenous nitrogen.This study found that the enrichment of NO_3^--N greatly enhanced the total N_2O production of wetland soils and significantly altered the original contribution patterns of biological and non-biological processes to N_2O production.Thus,special attention should be

关 键 词：恢复湿地 N2O 硝化-反硝化作用 氮输入 黄河口 

分 类 号：S154.1[农业科学—土壤学]