摘要
臭氧(O_(3))浓度升高危害小麦生长,现有研究尚不清楚推广新的小麦品种能否减缓O_(3)对籽粒产量、农田蒸散和水分利用效率的负面效应,且研究O_(3)浓度升高对麦田水分利用效率的影响对农业用水管理具有重要意义。该研究利用完全开放式O_(3)浓度升高平台(O_(3)-FACE),通过连续观测农田小气候特征,结合能量平衡法分析O_(3)浓度升高对麦田水热通量、小麦籽粒产量和田间水分利用效率的影响。结果表明:O_(3)浓度升高显著降低了开花后第32天小麦旗叶的叶绿素含量,降低了乳熟–成熟期的麦田潜热通量平均值和正午峰值,但影响幅度较小。O_(3)浓度升高对麦田平均水热通量及其分配无显著影响,也未影响籽粒产量、产量组成和田间水分利用效率。不同于10年前江淮地区主推的扬辐麦2号、烟农19和嘉兴002等品种,当前推广的农麦88表现出极强的O_(3)抗性。在O_(3)浓度不断升高背景下,种植农麦88有助于减缓O_(3)浓度升高对田间蒸散和水分利用效率的影响。
Tropospheric ozone(O_(3))has often formed in the emission of volatile organic compounds and nitrogen oxides from human activities.The elevated O_(3)concentration can seriously reduce the photosynthetic rate of wheat in the late grain-filling stage.The resulting loss of wheat yield can then threaten the food security and the carbon-water cycle of farmland ecosystems.Particularly,there is a closely coupled relationship between grain yield and field water use of wheat.Taking the Nongmai 88 variety as the research object,this study aims to investigate the impacts of elevated O_(3)on farmland water and heat flux in the wheat field.The response of wheat field transpiration to elevated O_(3)concentrations was also determined using free air ozone concentration enrichment system(O_(3)-FACE)simulation.The field microclimate was continuously monitored on AA(ambient air)and E-O_(3)(1.5×ambient O_(3)concentration)in O_(3)-FACE.There was a great variation in the water and heat flux at different stages of wheat growth under elevated O_(3),according to the residual energy balance.The results show that latent heat flux was an important energy consumption item of wheat farmland ecosystem,accounting for 61.65%(AA)and 63.77%(E-O_(3))of energy expenditure,respectively.Sensible heat flux and soil heat flux accounted for 24.50%(AA),21.07%(E-O_(3))and 13.95%(AA),15.20%(E-O_(3)),respectively.In terms of diurnal variation,net radiation,soil heat flux,both sensible and latent heat flux shared the"n"type unimodal trends,reaching the maximum at noon.The net radiation increased gradually during the wheat growing season.Whereas,the latent heat flux showed a trend of first increasing and then decreasing.The sensible heat flux was opposite to the latent one,indicating the trend of first decreasing and then increasing.The latent heat flux decreased in the senescent leaf,while the sensible heat flux increased rapidly.There was no significant effect of elevated O_(3)on the net radiation,soil heat flux,sensible and latent heat flux,as well as their energy distribution from the wheat jointing to the milk maturity stage.The elevated O_(3)also accelerated the senescence of wheat leaf in the period from milk ripening to ripening,leading to a reduction in the chlorophyll content.There was a great decrease in the mean and peak value of latent heat flux and evapotranspiration.However,the elevated O_(3)had no significant effect on evapotranspiration,grain yield and water use efficiency.As such,excellent O_(3)resistance was achieved to cultivate this variety under the elevated O_(3),especially for the high grain yield and water use efficiency in the wheat field.This finding can provide new evidence to evaluate the water and heat flux of winter wheat farmland,in order to simulate the farmland water use and grain yield under elevated O_(3)and variety replacement.
作者
徐诗韵
徐彦森
张宇杰
冯兆忠
XU Shiyun;XU Yansen;ZHANG Yujie;FENG Zhaozhong(Collaborative Innovation Center for Meteorological Disaster Forecasting,Early Warning and Evaluation,Nanjing University of Information Science and Technology,Nanjing 210044,China;Jiangsu Provincial Key Laboratory of Agricultural Meteorology,Nanjing University of Information Science and Technology,Nanjing 210044,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2024年第8期116-124,共9页
Transactions of the Chinese Society of Agricultural Engineering
基金
江苏省自然科学基金项目(BK20220448)
国家自然科学基金项目(42207123,42130714)
江苏省高校面上基金项目(22KJB180019)。
关键词
臭氧
水热通量
产量
蒸散发
冠层温度
小麦
ozone
water and heat flux
yield
evapotranspiration
canopy temperature
wheat
作者简介
徐诗韵,研究方向为环境变化下的农田水热通量。Email:xsy_mail@126.com;通信作者:徐彦森,博士,研究方向为臭氧污染的生态效应。Email:yansenxu@nuist.edu.cn。
