高强度农业种植区不同景观池塘氧化亚氮排放特征  

Nitrous Oxide Emissions from Ponds in Typical Agricultural Catchment with Intensive Agricultural Activity

作　　者：张欣悦 肖启涛 谢晖 刘臻婧 邱银国 罗菊花[2] 徐向华[1] 段洪涛[2] ZHANG Xin-yue;XIAO Qi-tao;XIE Hui;LIU Zhen-jing;QIU Yin-guo;LUO Ju-hua;XU Xiang-hua;DUAN Hong-tao(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD),Nanjing University of Information Science&Technology,Nanjing 210044,China;Key Laboratory of Watershed Geographic Sciences,Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences,Nanjing 210008,China;Hunan Climate Center,Changsha 410118,China)

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心,南京210044 [2]中国科学院南京地理与湖泊研究所流域地理学重点实验室,南京210008 [3]湖南省气候中心,长沙410118

出　　处：《环境科学》2024年第4期2385-2393,共9页Environmental Science

基　　金：江苏省碳达峰碳中和科技创新专项(BK20220018);国家自然科学基金项目(42271114);中国科学院青年创新促进会会员项目(2023329)。

摘　　要：农业流域水体氮循环过程与农业活动有着十分紧密联系,会随着农业活动的持续进行而成为大气N_(2)O的重要排放源.小型池塘具有灌溉、蓄水和纳污等多种功能,是农业种植区和农村景观的重要组成部分.以巢湖北岸典型农业流域烔炀河流域为研究对象,选取3种不同类型(村塘、农塘和水塘),共计6个池塘,于2020年9月至2021年9月连续采样观测,探究了农业流域不同景观池塘N_(2)O排放特征及其影响因素.结果表明,用于生活污水承纳的村塘N_(2)O排放最高,其次为用于农业灌溉的农塘,其N_(2)O排放通量分别为流域自然水塘排放量[(1.33±2.50)μmol·(m^(2)·d)^(-1)]的8倍和4倍.连续观测表明不同景观池塘N_(2)O排放表现出明显的时间变化特征,但其N_(2)O排放时间变化的调控因子有所不同.其中,村塘与农塘N_(2)O排放主要受氮负荷和降雨影响,而远离村庄农田的水塘N_(2)O排放变化主要受水温驱动.烔炀河流域池塘是大气N_(2)O显著排放源,年均N_(2)O排放通量为(5.73±10.61)μmol·(m^(2)·d)^(-1),农业氮负荷输入是其N_(2)O高排放的主要原因,明晰池塘用途和类型对估算农业流域小型水体N_(2)O排放十分重要.The nitrogen cycle of water bodies in agricultural watersheds is closely related to the farmland ecosystem,which will become a significant emission source of atmospheric N_(2)O with increasing agricultural activity.Ponds are an important component of agricultural catchment due to their functions as water storage,domestic sewage receiving,and irrigation.In this study,Tongyang River Catchment,a typical agricultural catchment on the northern part of Chaohu Lake,was selected as the research object.Three different types of landscape ponds(sewage pond,irrigation pond,and storage pond)with a total number of six ponds were selected to investigate the N_(2)O emissions based on continuous field sampling from September 2020 to September 2021.The results showed that the highest N_(2)O emission flux occurred in sewage ponds,followed by the irrigation pond,and the N_(2)O emissions fluxes in the sewage pond and irrigation pond were eight times and four times higher than that in storage ponds[(1.33±2.50)µmol·(m^(2)·d)^(−1)],respectively.Continuous observation showed that N_(2)O emissions in different landscape ponds showed obvious temporal variation,but the factors influencing the N_(2)O emissions varied among ponds.The N_(2)O emissions from sewage ponds and irrigation pond were mainly affected by nitrogen load and precipitation,whereas N_(2)O emissions from ponds away from villages and farms were mainly affected by water temperature.In summary,the ponds acted as significant emission sources of atmospheric N_(2)O emissions,with an annual mean N_(2)O emissions flux of(5.73±10.61)µmol·(m^(2)·d)^(−1).Large exogenous nitrogen load input from the catchment contributed to significant N_(2)O emissions.Clarifying the use and type of ponds is important for estimating N_(2)O emissions from small-scale water bodies in agricultural watersheds.

关 键 词：农业活动 池塘水体 N_(2)O排放 时空变化 影响因素 

分 类 号：X16[环境科学与工程—环境科学]