生态科学2023，Vol.42Issue(6)：33-43,11.DOI:10.14108/j.cnki.1008-8873.2023.06.004
一次热浪事件对祁连山海晏草甸草原CO2通量的影响过程
Effects of a heat wave event on CO2 fluxes in Haiyan meadow grassland in Qilian Mountains
摘要
Abstract
The"heat wave"events caused by global climate change have a significant impact on the carbon cycle of alpine grassland.Heat wave,as a typical extreme climate event,directly affects plant growth and respiration,but also indirectly affects soil respiration,and then leads to changes in ecosystem respiration and CO2 flux in the"constant flux"layer.What is the effect of heat wave on CO2 flux in grassland ecosystem of Qinghai-Tibet Plateau?Taking the alpine meadow grassland in the northeast corner of the Qinghai-Tibet Plateau as the research object and the vorticity correlation system as the observation method,combined with continuously observed CO2 flux and micrometeorological data,in this study,we studied the effects of a long"hot day"heat wave event(from July 25 to August 2,2015)on net ecosystem carbon exchange(NEE),ecosystem respiratory(Re)and total primary productivity of the ecosystem(GPP)during 2010-2019.It turned out that heat wave can bring brief periods of heat and drought,the heat wave period(25 July to 2 August)compared to the pre-heat wave period(17 July to 24 July),the daily maximum temperature(Tamax),daily mean temperature(Ta),daily minimum temperature(Tamin),daily range(ADT),5 cm soil temperature(Ts)and vapor press deficit(VPD)increased by 42%,64%,146%,23%,46%and 35%,respectively.The precipitation(PPT)in the late phase of the heat wave(from August 3 to 10)was 77%lower than that in the pre-heat wave period.When the heat wave was over,air and soil temperatures won't immediately return to their pre-heat state,Tamax,Ta,Tamin and Ts were increased by 5%,22%,142%and 12%in the late phase of heat wave,respectively.In this heat wave event,hourly and daily CO2 flux in the early and late stage of the heat wave decreased significantly compared with the heat wave period,and hourly net CO2 absorption in the early and late stage of the heat wave decreased by 20.3%and 37.6%,respectively,compared with the heat wave period;hourly Re decreased by 16.8%and 13.8%,respectively;the hourly GPP decreased by 17.6%and 21.7%respectively.The daily net CO2 absorption decreased by 20.5%and 37.8%,the daily Re decreased by 16.7%and 13.6%,and the daily GPP decreased by 17.4%and 21.7%,respectively,compared with the heat wave period.关键词
草甸草原/热浪/CO2通量/涡度相关系统Key words
meadow grassland/heat wave/CO2 flux/vorticity correlation system分类
天文与地球科学引用本文复制引用
马文婧,李英年,张法伟,韩琳..一次热浪事件对祁连山海晏草甸草原CO2通量的影响过程[J].生态科学,2023,42(6):33-43,11.基金项目
国家自然科学基金项目(41877547) （41877547）
国家重点研发计划项目(2016YFC0501802) （2016YFC0501802）
科技部基础资源调查专项(2019FY101300) （2019FY101300）
