陇中半干旱区覆膜玉米净碳交换及其影响因素  

Net Carbon Exchange of Film Mulched Maize and Its Influencing Factors in the Semi-arid Area of Central Gansu Province

作　　者：周琳琳 丁林凯 阚飞[1] 刘红娟 魏国孝[1] ZHOU Linlin;DING Linkai;KAN Fei;LIU Hongjuan;WEI Guoxiao(College of Earth and Environmental Sciences,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]兰州大学资源环境学院,兰州730000

出　　处：《灌溉排水学报》2020年第S01期7-12,共6页Journal of Irrigation and Drainage

基　　金：国家自然科学基金项目(41471023)

摘　　要：【目的】探讨陇中半干旱区覆膜玉米农田生态系统的净碳通量特征及其影响因子。【方法】以陇中半干旱区覆膜玉米农田生态系统为研究对象,基于2016年玉米生长季(5—9月)的涡度相关数据和气象数据,分析了不同生育期内覆膜玉米农田生态系统的净CO2通量(NEE)的变化特征及其与环境因子的相关关系。【结果】(1)陇中半干旱区覆膜玉米农田生态系统在不同生育期内日尺度NEE变化呈现"U"型变化曲线,峰值出现在12:00—13:00之间,且固碳能力表现为灌浆期>成熟期>拔节期>幼苗期。(2)覆膜玉米农田生态系统在月尺度上NEE的变化呈现出"U"变化型曲线,整个生长季期间,NEE总值为-1108.00 mg/(m2·d),平均值为-8.03 mg/(m2·d),最小值出现在8月1日,为-26.5mg/(m2·d)。(3)覆膜玉米生态系统NEE与光合有效辐射、气温和饱和水汽压差呈显著负相关关系,且相关性表现为光合有效辐射>气温>饱和水汽压差,NEE与土壤温度呈正相关关系,与土壤含水率相关性不显著。【结论】陇中半干旱区覆膜玉米NEE变化在日尺度与与月尺度上均呈现"U"型变化曲线,NEE与环境因子相关性为光合有效辐射>气温>饱和水汽压差>土壤温度>土壤含水量。【Objective】The carbon cycle of farmland ecosystem plays an important role in the global climate change.We explore the net carbon flux characteristics and its influencing factors of the film mulched Maize Farmland Ecosystem in the semi-arid area of central Gansu.【Method】The paper takes the film mulched maize Farmland Ecosystem in the semi-arid area of central Gansu as the research object,based on the vortex of the maize growing season(May 1,2016 to September 14,2016)The change characteristics of net CO2 flux(NEE)and the correlation between NEE and environmental factors in different growth periods were observed and analyzed.【Result】(1)In the semi-arid area of central Gansu Province,the change of NEE showed a"U"curve in different growth periods,the peak value appeared between 12:00—13:00,and the intensity of carbon fixation was in the filling stage>mature stage>jointing stage>seedling stage.(2)The change of NEE of the film mulched maize farmland ecosystem on a monthly scale shows a"U"change curve.During the whole growing season,the total value of NEE was-1108.00 mg/(m2·d),the average value was-8.03 mg/(m2·d),the minimum value was-26.5 mg/(m2·d)on August 1.(3)NEE was significantly correlated with par,air temperature and swdp,and correlated par>air temperature>swdp.NEE was positively correlated with soil temperature,but not significantly correlated with soil water content.【Conclusion】The NEE change of film mulched maize farmland ecosystem in the semi-arid area of central Gansu showed a"U"-shaped change curve on both the daily and monthly scales.The correlation between NEE and environmental factors is photosynthetically active radiation>temperature>saturated vapor pressure difference>soil temperature>soil moisture content.

关 键 词：农田生态系统 净碳通量 环境因子 

分 类 号：S513[农业科学—作物学]