Soil Spatial Dependence in Three Arctic Ecosystems

Abstract

We examined the spatial variability of 13 soil physicochemical attributes and their correlation with soil gravimetric moisture content (θg) in 279 soil samples collected from three high arctic ecosystems. The observed correlations between θg and pH, NH4, NO3, total organic C, dissolved organic C, and dissolved organic N contents in the Arctic are considerably higher than temperate agricultural and tropical grassland soils, which suggests that θg plays a critical role in arctic soil ecosystems. We found that, despite the climatic extremities, arctic soil attributes are spatially well structured and their spatial dependency is consistent within and between the studied ecosystems. The range of spatial dependency, however, is considerably smaller, which can be ascribed to the environmental extremities and other periglacial features. Based on the results, we recommend that, to obtain independent samples, the minimum distance between samples should be 10 m in Haplorthels or Haploturbels and 45 m in Histels.