华东沿海稻麦轮作区生态系统能量闭合度和CO_(2)通量特征研究  

Characteristics of ecosystem energy closure and CO_(2) flux in a rice-wheat rotation area along the coast of East China

作　　者：徐敏 徐敬争 刘文菁[3] 徐萌 徐经纬[4] 高苹 罗晓春 XU Min;XU Jingzheng;LIU Wenjing;XU Meng;XU Jingwei;GAO Ping;LUO Xiaochun(Climate Center of Jiangsu Province,Nanjing 210008,China;Aerospace New Weather Technology Co.,Ltd,Wuxi 214028,China;Jiangsu Meteorological Bureau,Nanjing 210008,China;Key Laboratory of Meteorological Disaster,Ministry of Education/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science&Technology,Nanjing 210044,China;Jiangsu Meteorological Service Center,Nanjing 210008,China)

机构地区：[1]江苏省气候中心,南京210008 [2]航天新气象科技有限公司,无锡214028 [3]江苏省气象局,南京210008 [4]南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心,南京210044 [5]江苏省气象服务中心,南京210008

出　　处：《中国生态农业学报（中英文）》2022年第3期367-379,共13页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(42075118);科技助力经济2020重点专项(KJZLJJ202010);国家重点研发计划项目(2019YFD1002201)资助。

摘　　要：为科学评估华东沿海水稻-小麦轮作(简称“稻麦轮作”)农田生态系统能量通量变化特征和固碳能力,基于2019—2020年涡度相关系统观测的稻麦轮作全生育期通量数据,经质量控制,研究分析了太阳净辐射(R_(n))、潜热通量(LE)、显热通量(H)、土壤热通量(G)、CO_(2)通量(F_(C))多时间尺度变化特征和稻麦轮作系统固碳量及其环境影响因子。结果表明:有效能量和湍流通量能量平衡比率为0.80,能量闭合度较高,说明通量观测数据可靠。月均LE和R_(n)年内变化总体均呈“倒U型”,两者变化基本同步,峰值主要在5—8月,谷值主要在1—2月、11—12月。H和G的波动幅度明显小于LE和R_(n)。日内逐小时F_(C)呈“U型”单峰二次曲线,总体为白天吸收CO_(2)、夜间排放CO_(2),CO_(2)日吸收峰值主要出现在10:00—12:30;逐日F_(C)和逐月F_(C)在年内总体呈“W型”变化特征,全年碳排放时段主要集中在1月、6月、11—12月,其余均为碳吸收,吸收峰值分别在冬小麦拔节孕穗期(3—4月)和水稻拔节孕穗期(8月)。2019年和2020年的2—5月冬小麦生长期的固碳量分别为387.4 g(C)·m^(-2)和382.2 g(C)·m^(-2),7—10月水稻生长期的固碳量分别为678.2 g(C)·m^(-2)和599.7 g(C)·m^(-2);白天,若气温升高,冬小麦和水稻的CO_(2)吸收能力会随之增强,但当饱和水汽压差高于1.7 kPa时,会降低这种吸收趋势,夜间主要是受气温影响。由此可见,沿海稻麦轮作农田生态系统碳吸收能力有着明显的日变化和季节变化,全年尺度上是碳汇,且为强固碳区。To scientifically evaluate the variation characteristics of energy flux and the carbon sequestration capacity of a winter wheat and one-season rice rotation farmland ecosystem on the coast of East China,we collected flux observations in winter wheat and one-season rice rotation farmland from a vorticity field observation experiment throughout the growth period from 2019 to 2020.We used the flux data processing software of American LI-COR Company to control the data quality and obtained a set of 30 min data sequences.After quality control,carbon sequestration of rice and wheat and its environmental impact factors and multi-time scale variation characteristics of solar net radiation(R_(n)),latent heat flux(LE),sensible heat flux(H),soil heat flux(G),and CO_(2) flux(F_(C)) were studied and analyzed using energy balance and statistical methods.The results showed that the energy balance ratio of the effective energy and turbulent flux was 0.80,which indicated a high energy closure and reliable flux observations.The variations in monthly LE and R_(n) over the year showed an“inverted U”distribution,and these two variations were synchronous.The peak value mainly occurred from May to August,and the valley value mainly appeared from January to February and November to December.The fluctuation magnitudes of H and G were significantly lower than those of LE and R_(n).Hourly FC during the day presented a“U-shaped”single peak quadratic curve,thereby indicating that CO_(2) was generally absorbed during the day and discharged at night.The daily absorption peak of CO_(2) mainly occurred during 10:00-12:30.Daily and monthly FC generally showed“W-type”variation characteristics throughout the year.The annual carbon emission periods were mainly concentrated in January,June,November,and December,whereas the rest of the year was classified as a carbon absorption period.The absorption peaks were at the jointing and booting stages of winter wheat(March to April)and rice(August).The carbon sequestration during the growth perio

关 键 词：稻麦轮作 涡度相关 能量平衡 CO_(2)通量 固碳量 

分 类 号：S161.9[农业科学—农业气象学]