[A-CG38] 北極域の科学

[ACG38-P09] 東シベリアカラマツ林における凍土の季節融解深の時空間変動

*小谷 亜由美¹、太田 岳史¹、檜山 哲哉²、中井 太郎²、飯島 慈裕³、マキシモフ トロフィム⁴ (1.名古屋大学　生命農学研究科、2. 名古屋大学 宇宙地球環境研究所、3.三重大学　生物資源学研究科、4.寒冷圏生物研究所（ロシア）)

キーワード：融解層、カラマツ、土壌水分

This study investigated temporal and spatial variability of seasonal thaw depth at larch-dominated forests in the middle part of the Lena basin, eastern Siberia. We compared temporal and spatial variability of thaw depth at two larch-dominated forests mixed with birch and willow, in the southern and middle parts of the Lena basin. Difference in precipitation both of rain and snow and soil properties such as soil texture relate to difference in seasonal thawing speed and soil water content of the two forests. Field measurements of thaw depth using handheld dynamic cone penetrometer were repeated in each site in June–July (first half of summer) and September (before soil freezing). Although averages of thaw depth observed in the same season was not differ, their spatial variability showed contrast in two sites. Thaw depth relates to vertical mean penetration resistance in summer, while it relates to upper canopy and floor plant coverage in autumn observation.