半自然草地は重要な土壌炭素貯留庫：温帯草地ハビタット類型間の表層土壌炭素蓄積量の環境要因

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:土壌炭素推計においてハビタット類型・管理・水文を分離することの重要性を示す実証データとして有用。

🏢実務担当者:自然資本・生物多様性開示やサプライチェーン上の農地由来排出を検討する際、草地管理と土壌炭素の関係を理解する材料になる。

🏛政策担当者:Natura 2000草地の保全と炭素貯留を両立させる土地利用政策設計の根拠として参照できる。

ABSTRACT Aims Semi‐natural grasslands have been part of European landscapes for millennia, and their persistence and high biodiversity depend on continued low‐intensity management. However, carbon assessments often aggregate semi‐natural and cultivated grasslands despite their contrasting land‐use histories, management and soil conditions. We quantified soil organic carbon (SOC) stocks across semi‐natural and cultivated grassland habitat types in northeastern Europe and identified environmental variables associated with variation in SOC stocks. Location Estonia, northeastern Europe. Methods We measured SOC stocks in the topsoil (0–10 cm) at 227 sites representing 12 semi‐natural grassland habitat types occurring in Estonia that are listed in Annex I of the EU Habitats Directive, together with dry and wet cultivated grasslands. Linear regression models were used to assess associations between topsoil SOC stocks and vegetation structure, management, soil characteristics and climatic variables. Results SOC stocks in the upper 10 cm of soil ranged among grassland types from 21.7 ± 8.3 to 50.3 ± 14.3 t C/ha (mean ± SD). Dry cultivated grasslands had the lowest SOC stocks and significantly lower values than most semi‐natural grassland types. Wet cultivated grasslands on drained, peat‐influenced hydromorphic soils had intermediate SOC stocks. Among semi‐natural grassland types, calcareous alvar grasslands had the highest SOC stocks, whereas mesic grasslands had the lowest. Annual precipitation and precipitation seasonality were negatively associated with SOC stocks, while moss cover and Normalised Difference Vegetation Index (NDVI) were positively associated with SOC stocks. In grasslands on alluvial and coastal soils, grazed sites had higher SOC stocks than unmanaged sites. Conclusions Topsoil SOC stocks varied markedly among Natura 2000 semi‐natural grassland habitat types and between cultivated grassland types, reflecting the combined influence of soil characteristics, climate, vegetation structure and management. These findings highlight semi‐natural grasslands as important long‐term carbon reservoirs. Land‐use policies should account for habitat type and soil hydrology and prioritise the protection of carbon‐rich semi‐natural grasslands.

• openalex https://doi.org/10.1111/avsc.70091first seen 2026-10-18 04:51:43