[A-CG30] 陸域生態系における水・炭素・窒素などの循環に関する研究

[ACG30-17] 熱帯泥炭林に適用するための陸域生態系モデルにおける土壌サブモデルの改良

*平田 竜一¹、伊藤 昭彦¹、平野 高司²、三枝 信子¹ (1.国立環境研究所、2.北海道大学大学院農学研究院)

キーワード：炭素収支, 地下水位, 中央カリマンタン

We applied conventional model (Vegetation Integrative Simulator for Trace Gases; VISIT) to tropical peat forest data obtained from Palangkaraya (PDF) site in Kalimantan but it cannot simulate carbon balance accurately. Especially, ecosystem respiration (RE) showed opposite seasonal variation with observed RE because of misunderstanding of soil respiration process. Soil respiration process in conventional ecosystem model is controlled by only soil temperature and soil water content. In contrast, CO2 release from peat is regulated by not only these components but also water table. Soil respiration data obtained from PDF site shows that the response of soil respiration to wetness is also different from that in conventional model. In order to improve the response of soil respiration, we modify soil submodel of the model. Ground water level is simulated by tank model. We modify soil respiration function using the relationship between ground water level and soil respiration.