JapanFlux2024 JP-Hrt Hiratsuka Rice Paddy

The seasonal flux dynamics of CH4 and CO2 in paddy fields in temperate Japan and tropical Thailand and the greenhouse gas balance obtained as the sum of CH4 and CO2 will be evaluated to investigate in detail the dynamics and mechanisms of CH4 emissions in paddy fields in tropical Thailand.
Field experiments were conducted during rice-cropping seasons in rice farm paddy fields in Hiratsuka, Kanagawa prefecture, Japan in 2013 and at Kamphaeng Saen campus, Kasetsart University in Nakhon Pathom Province, Thailand in 2014.
The turbulent fluxes of sensible heat, latent heat, CO2 were measured using the eddy covariance system.The CH4 were measured using the HREA(Hyperbolic relaxed eddy accumulation) method and Chamber method.The controlling factors for GHG dynamics and budgets were examined in both climate areas, and field experiments were conducted at around heading and flowering stages when CH4 emission is usually large.

本研究将对日本温带与泰国热带地区稻田的甲烷（CH4）、二氧化碳（CO2）季节通量动态，以及由CH4与CO2累加得到的温室气体收支进行评估，以详细解析泰国热带稻田的甲烷排放动态与排放机制。
田间试验分别于2013年水稻种植季在日本神奈川县平冢市的农田稻田，以及2014年水稻种植季在泰国佛统府农业大学甘烹盛校区的农田稻田开展。
研究采用涡度协方差系统测定显热、潜热与CO2的湍流通量；采用双曲线松弛涡度积累法（Hyperbolic relaxed eddy accumulation）与箱式法测定CH4通量。针对两个气候区的温室气体（Greenhouse Gas，GHG）动态与收支调控因子展开分析，并于甲烷排放通常较高的抽穗与扬花期前后开展田间试验。