Temporal Changes Of Fertility And Spatial Distribution Of Heavy Metals Of Soils In Shengzhou

Status of soil fertility and heavy metal content in Shengzhou City were analyzed through a field survey conducted in 2014. Temporal changes of soil fertility were compared with previous soil surveys(year 2004 and the second National Soil Survey), so that to optimize soil fertility management. Spatial distribution analysis of soil heavy metals was carried out to elucidate the pollution factors. The main results were achieved:1. Results of soil survey in 2014 showed that the soils are acidic overall, being average p H 5.69. The average soil organic matter(SOM) content was 37.05 g/kg. Soil total nitrogen(N) content was 1.89 g/kg. Average soil available phosphorus(P) was 18.0 mg/kg. The average soil available potassium(K) was 102.2 mg/kg. Overall, since the second Soil Survey, soil organic matter content has increased but the distribution of reginal patterns has not changed much. The spatial variation of soil available P and K varied greatly in space, and situation of P and K deficiency was not improved. The soil available K was even decreased.2. Soil heavy metal analysis results revealed that contents of most of the soil heavy metals were within safe range, but in the whole survey area there existed spatial variation, There was a clear aggregation and discrete distribution of heavy metal content in the whole space sample points.3. Correlation analysis showed that lead(Pb) and cadmium(Cd) and selenium(Se) were strongly correlated, which was greatly affected by soil physical and chemical properties such as soil p H and organic matter content. The correlations between total nitrogen, available phosphorus, potassium and heavy metals were not significant.