Evaluation Of The Planting Tobacco Soil Fertility And Study On The Tobacco Fertilizing Technologies In Xuan-en

The paper evaluated the fertility of the planting tobacco soil in Xuan-en through getting sample in extensive areas and studied the using technologies of nutrient elements chlorine and magnesium primarily by analysis, field inquiry and field experiment. Then we got these conclusions:1. Xuan-en has six kinds of soil, six sub-kinds, thirteen-soil category and thirteen soil sorts. Yellow-brown soil and yellow soil is the main tobacco-growing soil.2. it is more suitable for the planting tobacco soil to produce high quality tobacco leaves, but there are a few factors influencing the tobacco growth and quality in Xuan-en. (1) The quantity of total nitrogen and available nitrogen in soil is more, the nitrogen of soil supplied is higher and the ability of offering nitrogen is stronger. The characteristic of soil supplement on nitrogen is not compatible with the absorbing nutrition rule of tobacco growth, and this is one of the most important reasons why the high quantity of nicotine in tobacco leaves. (2) Although the quantity of total P and available P in most tobacco-planting areas is more higher, comparing with the results of the second soil investigation, the offering pHospHorus ability of the tobacco- planting soil is remaining lower. Especially during the first tobacco growing stage, the lower soil temperature and lower pHospHorus activation has become one of the factors restricting the tobacco growth. (3) The offering K ability of the planting tobacco soil is the same, comparing with the result of the second soil investigation, because a lot of K were used in the tobacco growth. In general, the offering K ability of planting tobacco soil is not high. (4) The pH in the tobacco-planting soil is lower; the tobacco- planting soil has the current to acidification. (5) The quantity of the water-soluble chlorine in the tobacco-planting soil (especially the soil derived from carbonates), the ratio of exchange Mg to CEC is less, bellow 5% normally. If the value of the Ca\Mg is higher, the tobacco will be lack of magnesium. (6) The tobacco-planting soil is lack of micronutrient elements, such as boron...