Evaluation Of Soil Nutrient Status Of Tobacco Growingarea In Qianjiang Of Chongqing

Tobacco is an important economic crop in our country.Chongqing is one of the main producing areas of tobacco in our country.Its distribution area mainly includes the Wuling Mountain and the Three Gorges Reservoir area.Qianjiang is located in the hinterland of Wuling Mountain.It is one of the main producing areas of flue-cured tobacco in Chongqing.In 2012,the tobacco-growing soil in Qianjiang was investigated and sampled and analyzed.The pH,organic matter,nitrogen,phosphorus and potassium nutrients,The content of nutrient elements clarified the soil fertility status of tobacco-growing soil,and obtained the spatial distribution map of soil nutrients by using GIS technology.By comparing the soil nutrient status of tobacco-growing soil in Qianjiang 10 years ago,we understood the nutrient changes of tobacco-growing soil.Tobacco soil improvement and tobacco scientific fertilization provide data support.the result shows:(1)The soil acidification of tobacco planting in Qianjiang is serious and urgently needs improvement.It is recommended that the soil with pH<5 should be improved with lime,and the soil with pH<5.5 should be improved with dolomite powder or alkaline materials.(2)The average soil organic matter is 24.2 g/kg,and 57.0% of the soil organic matter is in the suitable range;the total soil nitrogen and alkali-hydrolyzable nitrogen in this area are more suitable;the soil samples suitable for the total phosphorus range account for 55.6%,and the overall level On the low side;34% of the available phosphorus content is within the appropriate range;24.4% of the soils with available potassium below 150 mg/kg,with an average of 234 mg/kg,individual available potassium content is extremely high.Therefore,in the fertilization management of the corresponding regions,phosphorus and potassium should be controlled,while controlling the application of nitrogen fertilizer is still the focus of future work.(3)The analysis results of medium nutrient elements show that the content of exchangeable calcium and magnesium in this area is low,and more than 55% are extremely low and low.The content of effective sulfur is relatively abundant,and the ratio of effective sulfur higher than 50 mg/kg exceeds 50%.Therefore,in this part of the soil,the application of sulfur-containing fertilizers should be appropriately reduced,and calcium and magnesium fertilizers should be increased.(4)The analysis results of micronutrient elements show that the tobacco-growing soil in Qianjiang has the characteristics of high sulfur,high iron,high manganese,high zinc,high copper,low chlorine,and low boron.The fertilization management requires appropriate supplement of chlorine and also requires approval Improve the effectiveness of pH to reduce copper,zinc,iron,and manganese,increase the application of boron fertilizers,and apply molybdenum fertilizers with reference to the soil molybdenum content.