摘要
冻融是高纬度、高海拔及部分温带地区普遍存在的一种自然现象。冻融可以显著改变冻融交替期土壤二氧化碳(CO_(2))排放通量。为全面了解不同陆地生态系统在冻融期CO_(2)的排放规律,本研究利用文献调研方法对1990—2020年同行发表的37篇相关文献进行Meta分析,系统分析冻结温度和循环次数对农田、森林、湿地和草原4种生态系统土壤CO_(2)排放的影响。结果显示:野外实地条件下,与未冻融处理相比,弱冻结条件下农田、森林和草原土壤CO_(2)排放量分别增加了44.2%、25.5%和56.0%,而湿地生态系统土壤CO_(2)排放量降低了10.1%,中冻结和强冻结对4种生态系统的土壤CO_(2)排放速率均呈抑制作用;室内模拟条件下,除草原生态系统在中冻结外,不同冻融强度对4种生态系统土壤CO_(2)排放量均有促进作用,平均增幅46.3%~272.5%。土壤CO_(2)排放峰值出现在冻融作用初期,之后随着冻融交替次数的增加,土壤CO_(2)排放速率逐渐降低至稳定水平。本分析结果有助于更好地了解不同生态系统土壤CO_(2)排放对冻融的响应,为今后深入开展相关研究工作奠定基础。
Freeze-thaw is a natural phenomenon at high elevation and high latitude,as well as some temperate regions.Many studies have shown that soil carbon dioxide(CO_(2))emission flux is strongly influenced by freeze-thaw,indicating that soil CO_(2)emission during freeze-thaw period is non-negligible in annual CO_(2)emission.To better understanding the variations of CO_(2)emission among terrestrial ecosystems during the freeze-thaw period,the effects of freezing temperature and freeze-thaw cycles on farmland,forest,wetland and grassland ecosystems were analyzed by collecting data from 37 papers published from 1990 to 2020.Compared to non-freeze-thaw treatment in the field condition,soil CO_(2)emission under weak freeze-thaw treatment on farmland,forest,and grassland were increased by 44.2%,25.5%and 56.0%,respectively,and was decreased by 10.1%in wetlands;while soil CO_(2)emissions of four types of ecosystems under medium and strong freeze-thaw conditions were inhibited.In the laboratory condition,soil CO_(2)emissions of the four ecosystems were promoted,with an average increase of 46.3%-272.5%under different freeze-thaw intensities,except for grassland ecosystem under the medium freeze-thaw condition.The peak value of soil CO_(2)emission appeared at the early stage of freeze-thaw.After that,soil CO_(2)emission rate gradually decreased to a stable level with increasing frequency of freeze-thaw cycles.This study helps to better understand the responses of soil CO_(2)emissions from different ecosystems to freeze-thaw conditions and lays a foundation for further research.
作者
王旭
李斐
赵世翔
WANG Xu;LI Fei;ZHAO Shi-xiang(College of Grassland,Resources and Environment,Inner Mongolia Agricultural University,Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resources,Hohhot 010018,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2022年第10期1932-1939,共8页
Chinese Journal of Ecology
基金
国家自然科学基金项目(4190071187)
内蒙古自治区自然科学基金项目(2019BS04005)资助。
关键词
冻融
碳排放
二氧化碳
生态系统
荟萃分析
freeze-thaw
carbon emission
carbon dioxide
ecosystem
meta-analysis
