• Title/Summary/Keyword: linear quadratic control

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Environmental Controls on Net Ecosystem CO2 Exchange during a Rice Growing Season at a Rice-Barley Double Cropping Paddy Field in Gimje, Korea (김제 벼-보리 이모작 논에서 벼 재배기간 동안의 순생태계 CO2 교환량에 대한 환경요인 분석)

  • Shim, Kyo Moon;Min, Sung Hyun;Kim, Yong Seok;Jeong, Myung Pyo;Hwang, Hae;Kim, Seok Cheol;So, Kyu Ho
    • Journal of Climate Change Research
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    • v.5 no.1
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    • pp.71-81
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    • 2014
  • Using the Eddy Covariance technique, we analyzed seasonal variation in net ecosystem $CO_2$ exchange (NEE) and investigated the effects of environmental factors and aboveground biomass of rice on the $CO_2$ fluxes in a rice-barley double cropping paddy field of Gimje, Korea. Quality control and gap-filling were conducted before this investigation of the effects. The results have been showed that NEE, gross primary production (GPP), and ecosystem respiration (Re) during the rice growing period were -215.6, 763.9, and $548.3g\;C\;m^{-2}$, respectively. Relation between NEE and net radiation (Rn) could be described by a quadratic equation, and about 65 % of variation in NEE was explained by changes in Rn. On the other hand, an exponential function relating Re to soil temperature accounted for approximately 43 % of variation in Re under the flooded condition of paddy field. Aboveground biomass showed significant linear relationships with NEE ($r^2=0.93$), GPP ($r^2=0.96$), and Re ($r^2=0.95$), respectively.