Soil organic carbon (SOC) stocks at national level were estimated to provide more accurate estimates on SOC for the Lithuanian GHG inventory. The SOC stocks in the forest floor, grassland litter, and in mineral or organic topsoil (0–30 cm) of forest land, grasslands, and croplands were estimated. The assessment was based on forest floor and peat topsoil mass, mineral topsoil bulk density, and carbon concentration in 754 permanent observation plots on 9 × 9 km grid of the National Forest Inventory in Lithuania. The SOC stocks were obtained for eight WRB Reference Soil Groups to provide the estimates for land use, land-use change, and forestry reporting. The SOC stocks in the forest floor, topsoil of mineral, and peat layers were identified for soils under different land uses. The mean SOC concentrations in the 0–10 and 10–30 cm topsoil of most soil groups, especially fertile forest soils (Cambisols, Luvisols +Retisols) were higher for forest land and grasslands, and lower for croplands. The total averaged SOC stock in the forest floor in mineral and organic soils was 6.97 t ha⁻¹, whereas in the litter of grasslands it was 0.54 t ha⁻¹. The averaged SOC stock in topsoil varied from 56 t ha⁻¹ (Arenosols) to 118 t ha⁻¹ (Cambisols) in mineral forest soils and was 150 t ha⁻¹ (Histosols) in organic forest soils. The total averaged SOC stock in mineral topsoil of forest land, grassland, and cropland was 80, 74, and 72 t ha⁻¹, respectively.

中文翻译：

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立陶宛矿物和有机土壤中有机碳储量的评估

估算了国家层面的土壤有机碳 (SOC) 储量，以便为立陶宛温室气体清单提供更准确的 SOC 估算值。估算了林地、草地凋落物以及林地、草地和农田的矿物或有机表土（0-30 cm）中的 SOC 储量。评估基于立陶宛国家森林清单 9 × 9 公里网格上的 754 个永久观测样地中的森林地面和泥炭表土质量、矿物表土容重和碳浓度。获得了 8 个 WRB 参考土壤组的 SOC 储量，以提供土地利用、土地利用变化和林业报告的估计值。为不同土地利用下的土壤确定了森林地表、矿物表土和泥炭层中的 SOC 储量。大多数土壤组的 0-10 和 10-30 cm 表层土壤中的平均 SOC 浓度，尤其是肥沃的森林土壤（Cambisols、Luvisols + Retisols），林地和草地较高，农田较低。矿质和有机土壤中森林地面的 SOC 总平均储量为 6.97 吨·公顷^-1，而在草地凋落物中为 0.54 t ha ^-1。表层土壤的平均 SOC 储量在矿物森林土壤中从 56 t ha ^-1 （Arenosols ）到 118 t ha ^-1 （Cambisols）不等，在有机森林土壤中为 150 t ha ^{-1 （Histosols）。}林地、草地和农田矿物表层土壤的总平均有机碳储量分别为 80、74 和 72 t ha ^-1。