日本地球惑星科学連合2022年大会

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[J] ポスター発表

セッション記号 A (大気水圏科学) » A-CG 大気海洋・環境科学複合領域・一般

[A-CG39] 陸域生態系の物質循環

2022年6月3日(金) 11:00 〜 13:00 オンラインポスターZoom会場 (12) (Ch.12)

コンビーナ:加藤 知道(北海道大学農学研究院)、コンビーナ:市井 和仁(千葉大学)、伊勢 武史(京都大学フィールド科学教育研究センター)、コンビーナ:寺本 宗正(鳥取大学乾燥地研究センター)、座長:加藤 知道(北海道大学農学研究院)

11:00 〜 13:00

[ACG39-P01] 中国地方の森林土壌におけるメタン吸収速度の空間変動要因

*寺本 宗正1、梁 乃申2、孫 力飛2、近藤 俊明3、小嵐 淳4、安藤 麻里子4、高木 正博5、山中 典和1、平野 高司6、高木 健太郎6、石田 祐宣7、市井 和仁8、高橋 善幸2、ホ ルチャ1 (1.鳥取大学、2.国立環境研究所、3.国際農林水産業研究センター、4.日本原子力研究開発機構、5.宮崎大学、6.北海道大学、7.弘前大学、8.千葉大学)

キーワード:メタン、チャンバー、土壌水分、空間変動、火山灰土壌

Forest soil is an important sink of atmospheric methane (CH4) in natural terrestrial ecosystems. However, there is still large uncertainty for the spatial variation of CH4 uptake rate in forest soils. In this study, we conducted field measurements for soil CH4 flux and environmental parameters in forests in Western Honshu to examine the dominant factors for spatial variation of soil CH4 uptake rate.

Measurements were conducted in late November in 2021 in five forest sites (a Japanese cedar forest site, a deciduous broad-leaved forest site, a beech forest site, a mixed forest site, and a red pine forest site) in research forests that belong to Tottori University. PVC collars (30 cm inner diameter, 4 cm depth, n = 15 to 20) were set in measurement points in each forest site one day before measurement. In those measurement points, we measured CH4 flux using a portable automated chamber measurement system consisting of two cylindrical aluminum chambers (30 cm in diameter, 30 cm tall) and a control box. At the same time, soil temperature and soil moisture at the depth of 0-5 cm were also measured near each measurement point.

There were significant negative relationships between soil moisture and soil CH4 uptake rate in the beech forest site and the red pine forest site. On the other hand, there was no significant relationship between soil moisture and soil CH4 uptake rate in the Japanese cedar forest site, the deciduous broad-leaved forest site, and the mixed forest site. From those results, it was suggested that heterogeneity of surface soil moisture can partly explain the spatial variation of soil CH4 uptake rate in some forest ecosystems, but we also need to consider other soil physicochemical and biological parameters for a better explanation for the variation.