Although nation-wide assessments on the grassland soil carbon storage have been conducted in Japan, the uncertainty of the estimation accuracy remains with its local variability. In the present study, using geostatistical approach, we assessed the spatial variability and distribution pattern of organic carbon (OC) and estimated its total stock in the surface soils (0–5 cm) over Mt. Wakakusa grassland (30.2 ha) of Central Japan. The exploratory statistics indicated that the surface soils had 1.88 ± 0.28 kg C m⁻² of soil OC density on average (n = 147) with a moderate variability (CV = 18.8%), while the geostatistical analysis unveiled that its semivariogram was well fitted by a spherical model (R² = 0.93, RSS = 1.15E⁻⁰⁵) and had a strong spatial dependency (nugget–sill ratio = 0.31). Based on these results, we constructed an interpolated map and estimated total OC stock to 552 Mg C in the surface soil of Mt. Wakakusa grassland.

中文翻译：

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山地表碳储量的地统计学估计。日本若草草原

尽管日本已经在全国范围内对草地土壤碳储量进行了评估，但估算准确性的不确定性仍然取决于其局部差异。在本研究中，我们使用地统计学方法评估了有机碳（OC）的空间变异性和分布模式，并估计了Mt上表土（0-5 cm）中的总碳储量。日本中部的若草草原（30.2公顷）。勘探统计数据表明，表层土壤的平均土壤有机碳密度平均为1.88±0.28 kg C m ^-2（n  = 147），且具有中等变化性（CV = 18.8％），而地统计学分析表明，其半变异函数非常适合通过球形模型（R ²  = 0.93，RSS = 1.15E ^-05），并且具有很强的空间依赖性（金块与底梁之比= 0.31）。基于这些结果，我们构建了一个插值图，并估算了山地表土壤中的总OC存量为552 MgC。若草草原。