Aanalysis of Soil Characteristics at Different Altitudes of Basic Tobacco Field in Luoyang

The state of soil fertility in the basic tobacco fields of Luoyang at different altitudes were evaluated based on the analysis of 105 soil samples.The results showed that:pH of soil were between 5.5~7.6 above 300 m of atitude,which were suitable to produce high quality tobacco leaves;the content of soil organic matter decreased with the increasing of elevation and it was the highest under 300 m of atitude.The content of soil organic matter was low and it had not significant differences above 500 m of atitude;the content of nitrogen and phosphorus in soil had small changes with elevation and had not significant laws;the content of slowly available potassiun increased evidently with the increasing of altitude,and the available potassiun in soil were slightly higher than that of the upper limit of producing high quality tobacco;the boron was microelement in soil had small changes with elevation,which were in a medium low condition,and the available copper decreased with the increasing of elevation,which all belonged to the middle high level;the soil available manganese and iron increased with the altitude increasing,and their contents were richer;the soil available zinc increased with the increasing of elevation above 300 m;the contents of lead and cadmium had conformed to the standards 2 of soil environment quality at each altitude;the contents of water-soluble chlorine in soil which was suitable to tobacco growing were between 4.83~5.52 mg/kg,and there were little differences with changes of elevation.