Spatial Heterogeneity and Distribution Patterns of Soil Nutrients in Sloping Field of Swida wilsoniana Young Plantation

Spatial heterogeneity and distribution patterns of soil nutrients (0-20cm)in sloping field were studied by geostatistical method in a Swida wilsoniana young plantation in northern Fujian Province. The results showed that soil organic matter, readily oxidized organic carbon, hydrolyzed nitrogen, available phosphorus and available potassium in sloping field have a good spatial autocorrelation, the autocorrelation functions performed the same pattern of developing from positive to negative direction with inflection point from 35m to 66m. Spatial variability of different soil nutrients was great. The bestfitting model for readily oxidized organic carbon is exponential model, and gaussian model is optimal model for the other soil nutrients. The ratio of nugget/sill for soil organic matter was higher than 25%, showing a moderate spatial variability. The other 4 ratios of nugget/sill for the soil available nutrients were lower than 25%, and they had spatial autocorrelation of intensity, spatial variability of these soil available nutrients mainly caused by structural variation and less affected by random factors. The spatial distribution of SOM, ROC and AP had a relatively good continuity, followed by AN and AK had a poor spatial continuity with higher degree of fragmentation, a strong variation was formed on the small scale. In this study, spatial variability of soil nutrients in slope field was mainly related to slope position, microtopography and other environmental factors, additionally, the input of uneven logging residue and prescribed burning may also have a significant impact on spatial variability of soil nutrients.