The spatial distribution and impact factors of soil properties on the five southern islands of Miaodao Archipelago in China

Soil is considered as the foundation of island ecosystem and of has great significances for maintaining the ecosystem vitality. Soil properties on islands were influenced by various factors due to the unique natural environmental conditions and increasing human activities. The five southern islands of Miaodao Archipelago were used as the study area, on the basis of field investigation and remote sensing method, the spatial distribution and impact factors of soil properties were analyzed in sampling plot and island scales. The results indicated that:The mean values of moisture content, pH, salinity, organic matter, total carbon, total nitrogen, available phosphorus and available potassium were 18.98%, 6.53, 0.088%, 20.75 g/kg, 15.05 g/kg, 1.23 g/kg, 3.83 mg/kg and 85.87 mg/kg, respectively. Distinct spatial heterogeneities exited between different islands and within islands. In sampling plot scale, land cover types and vegetation growth conditions were the main factors influencing soil properties; terrain factors affected soil via influencing land cover types; distances to the shore had little effects on the spatial distribution of soil properties. In island scale, the soil properties were insensitive to the impact factors on the whole.