玛曲高寒草甸生态系统碳水通量与水分利用效率特征研究

展开
  • 1. 中国科学院西北生态环境资源研究院 冰冻圈科学与冻土工程全国重点实验室,甘肃 兰州 730000
    2. 中国科学院青海湖综合观测研究站,青海 刚察 812300
    3. 中国科学院大学,北京 100049
    4. 中国气象局兰州干旱气象研究所,甘肃 兰州 730020

网络出版日期: 2025-05-20

基金资助

国家自然科学基金项目(4207509042275096

Study on the Characteristics of Carbon and Water Fluxes and Water Use Efficiency in the Alpine Meadow Ecosystem on Maqu

Expand
  • 1. Northwest Institute of Ecological Environment and ResourcesChinese Academy of Sciences/ Key Laboratory of
    Cryospheric Science and Frozen Soil Engineering
    Lanzhou 730000GansuChina
    2. Comprehensive Observation and Research Station for Qinghai LakeChinese Academy of SciencesGangcha 812300QinhaiChina
    3. University of Chinese Academy of ScienceBeijing 100049China
    4. Institute of Arid MeteorologyChina Meteorological AdministrationLanzhou 730000GansuChina

Online published: 2025-05-20

Supported by


摘要

研究青藏高原高寒草甸生态系统碳水通量及水分利用效率(WUE)特征对准确评估气候变化背景下高寒草地生态系统的碳收支、水循环及碳水耦合具有重要意义。本文利用 2012-2017年青藏高原东部中国科学院西北生态环境资源研究院若尔盖高原湿地生态系统研究站玛曲观测点高寒草甸下垫面的涡动相关系统的观测资料,分析了生长季碳水通量、WUE的变化特征,并结合多元逐步回归和结构方程模型两种统计方法,得到了生长季碳水通量和WUE变化的主要驱动因子。结果表明:(1)玛曲高寒草甸生态系统 6 年的年平均净生态系统碳交换(NEE)、生态系统呼吸(Re)和总初级生产力(GPP)分别为-109. 7798. 6908. 3 gC·m-2·a-1,整体呈碳汇;蒸散(ET6年年平均值为 446. 5 kg·m-2·a-1WUE 6年平均值为2. 0 gC·kg-1。(2)生长季NEEGPP日变化呈现明显的单峰型,在一日14:00(北京时,下同)左右达到峰值,Re全天变化较为平缓,夜晚略低于白天;ET日变化呈单峰型,月平均值和月累积值在7月达到最大;WUE日变化呈不对称的“U”型曲线,最小值出现在13:00-14:00WUE日值和日变化幅度在78月较大。(3)在生长季,多元逐步回归和结构方程模型均证实了温度在控制碳通量中的主导作用,以及辐射在控制ET中的主导作用,温度和太阳辐射是生长季WUE的主要影响因素。

本文引用格式

高叶荣, 李锁锁, 王少影, 潘永洁, 曾鼎文 . 玛曲高寒草甸生态系统碳水通量与水分利用效率特征研究[J]. 高原气象, 0 : 1 . DOI: 10.7522/j.issn.1000-0534.2025.00001

Abstract

Research on the characteristics of carbon and water fluxes and water use efficiencyWUEin the al‐ pine meadow ecosystem of the Qinghai-Xizang Plateau is of crucial significance for accurately assessing the car‐ bon balancewater cycleand carbon-water coupling of the alpine grassland ecosystem under the background of climate change. In this studybased on the observation data made using eddy correlation in the alpine meadow on the eastern Qinghai-Xizang Plateau from 2012 to 2017from the Maqu observation point of the Zoige Wet‐ land Ecosystem Research Station of the Northwest Institute of Eco-Environment and ResourcesChinese Academy of Scienceswe analyzed the changes in carbon and water fluxes and WUE during the growing season. By combining multiple stepwise regression and structural equation modelingwe explored the main driving factors of carbon and water fluxes and WUE during the growing season. The results indicate that:(1The average annual net ecosystem CO2 exchangeNEE),ecosystem respirationRe),and total gross primary productivity GPPof the Maqu alpine meadow ecosystem over 6 years were -109. 7798. 6and 908. 3 gC·m-2·a-1respectivelyshowing an overall carbon sinkthe annual average evapotranspirationETis 446. 5 kg·m-2·a-1 the 6-year average water use efficiencyWUEwas 2. 0 gC·kg-1.2The daily variations of NEE and GPP during the growing season showed a distinct unimodal patternpeaking around 14:00Beijing Timethe same as after),while Re showed a relatively flat diurnal patternlower slightly at night than during the daythe daily variation of ET exhibited a unimodal patternwith peak monthly and monthly accumulative values in JulyWUE dis‐ played an asymmetric "U" curve with the minimum value at 13:00-14:00showing significant daily and monthly variations in July and August.3During the growing seasonboth multiple stepwise regression and structural equation models confirmed the dominant role of temperature in controlling carbon fluxes and radiation in control‐ ling ET. Temperature and radiation were identified as the main influencing factors for WUE during the growing season.

文章导航

/