Soil Fertility Development Trends in Sloping Lands Under Different Habitats in Xinzhou of North China

The purpose of this paper was to study the impact of different land slope and different altitudes on soil fertility and desalination trends in soils of Xinzhou,north China.The results showed that:Lands with slope from 5° to 15° had the lowest contents of soil organic matter,available potassium and slowly available potassium,while that above 15°got the highest content.The contents of available nitrogen and available phosphorus decreased with increasing slope.Below altitude of 1 000m,lands with slope from 5°to 15°had the lowest contents of Fe,Zn,B,Mo and S,and that increased with increasing slope when the altitude above 1 000m,indicating that the soil erosion had the greatest in slope from 5°to 15°.Soil organic matter and total nitrogen content in sunny slope was less than that of shade slope,and the contents increased with the rising of gradient,soil pH showed the opposite trend.The interaction of slope direction and gradient affected the content of alkalinity nitrogen,available phosphorus and available potassium.Under different altitude,soil salinity and pH value were the lowest with slope from 5° to 15°.And salinity in soil of slope from 0 to 5° was the highest below altitude of 1 000m,significantly higher than that from 5° to 15°.Soil salinity content showed a deceasing trend with increasing altitude.The results also indicated that soil desalination effect enhanced with increasing altitude.