水分和温度交互作用下城市景观水体湖滨带沉积物CO_(2)、CH_(4)和N_(2)O排放研究  

The Impact of soil Moisture and Temperature on GHGs Emission of Lakeshore Zone Sediments-A Case Study of Urban Landscape Water Body in Nanjing

作　　者：杨伊琳 张丹奕 刘艺轩 周旭东 余杰予 于志国 YANG Yi-lin;ZHANG Dan-yi;LIU Yi-xuan;ZHOU Xu-dong;YU Jie-yu;YU Zhi-guo(School of Hydrology and Water Resources,Nanjing University of Information Science and Technology,Nanjing 210044,Jiangsu Province,China;Key Laboratory of Hydrometeorological Disaster Mechanism and Warning of Ministry of Water Resources,Nanjing University of Information Science and Technology,Nanjing 210044,Jiangsu Province,China;Kunming Xi-Shan District Meteorological Bureau,Kunming 650228,Yunnan Province,China;School of Earth System Science,Tianjin university,Tianjin 300072,Tianjin,China;Eco-Environment Research Department,Nanjing Hydraulic Research Institute,Nanjing 210029,Jiangsu Province,China)

机构地区：[1]南京信息工程大学水文与水资源工程学院,江苏南京210044 [2]水利部水文气象灾害机理与预警重点实验室,江苏南京210044 [3]昆明市西山区气象局,云南昆明650228 [4]天津大学地球系统科学学院,天津300072 [5]南京水利科学研究院生态环境研究所,江苏南京210029

出　　处：《中国农村水利水电》2024年第4期111-121,140,共12页China Rural Water and Hydropower

基　　金：国家自然科学基金面上项目(41877337)。

摘　　要：为模拟极端天气条件下关键的环境因子对城市景观水体湖滨带温室气体(GHGs)排放的影响,本研究以GHGs高排放样地-南京星甸湿地公园为研究对象,采集湖滨带表层沉积物进行室内培养,探讨在不同水分和温度条件下沉积物GHGs累计排放量和理化性质的变化差异。研究发现:①长期高温会抑制土壤呼吸,30℃淹水处理组在培养前期的GHGs排放速率是培养后期的1.6~4.1倍,这是由于随着培养时间的增长环境内DOC含量和C/N下降,有限碳含量不足以维持现有微生物生存需求,大量微生物死亡,不利于GHGs的排放;②在适宜温度内,水分增加和温度升高都会促进城市景观水体湖滨带沉积物GHGs的排放,这是由于淹水和增温都有利于沉积物中的厌氧微生物的繁殖与代谢,加速了有机质(DOM)-类富里酸的分解,CO_(2)和CH_(4)作为微生物分解DOM的副产物也增加了排放总量,此外,增温有利于影响硝化-反硝化过程的生物酶的活性,N_(2)O的排放总量也有所增加。结果表明:未来应该高度关注不同环境条件下外源溶解性碳输入对景观水体温室气体排放的影响,为准确评估城市景观水体对全球碳排放的贡献并制定减排政策提供重要理论依据。This study is dedicated to a comprehensive exploration of the intricate relationship between environmental factors and greenhouse gases(GHGs)emissions within the lakeshore zone of urban landscape water bodies,particularly under extreme weather conditions.The cho⁃sen research site,Nanjing Xingdian Wetland Park,stands out for its significant GHGs emissions.The investigation involved the meticulous collection of surface sediments from the lakeshore zone and an in-depth analysis of variations in cumulative GHGs emissions and physico⁃chemical properties of sediments.This comprehensive examination took place under diverse water and temperature conditions in controlled indoor cultures.The findings of this study have unearthed compelling insights.①To begin with,prolonged elevated temperatures were ob⁃served to have an inhibitory effect on soil respiration.Specifically,during the pre-cultivation period,the 30°C flooding treatment group ex⁃hibited GHGs emission rates 1.6 to 4.1 times higher than those observed in the post-cultivation period.This substantial difference can be at⁃tributed to the gradual decrease in dissolved organic carbon(DOC)content and the carbon-to-nitrogen(C/N)ratio within the environment over the course of incubation.The diminishing carbon content proved inadequate to sustain the survival requirements of microbial popula⁃tions,resulting in a significant decline,which in turn,hindered the emission of GHGs.②Furthermore,under appropriate temperature con⁃ditions,both increased moisture and temperature will promote GHGs emissions from sediments in the lakeshore zone of urban landscape wa⁃ter bodies.The favorable conditions for the reproduction and metabolism of anaerobic microorganisms in sediments,such as flooding and tem⁃perature elevation,accelerated the decomposition of dissolved organic matter(DOM),resembling fulvic acid.Consequently,this process led to heightened emissions of carbon dioxide(CO_(2))and methane(CH_(4))as by-products of the microorganisms'decomposition of DOM.More�

关 键 词：全球变化 甲烷 氧化亚氮 二氧化碳 景观水体 

分 类 号：TV11[水利工程—水文学及水资源] X16[环境科学与工程—环境科学]