| Topsoils (plough layer) developed from different parent materials under tobacco-rice rotation system in two land consolidation areas in Jinchengshi and Tangtianshi Towns of Shaoyang County were collected, and contents of soil available calcium (Ca), magnesium (Mg), sulfur (S),iron(Fe), manganese(Mn), copper(Cu), zinc(Zn), boron(B) and molybdenum(Mo) were analyzed. Results showed that1?the soil available Ca and S were relatively abundant, while the soil available Mg was relatively lower. The CV value of available S was in high level. Compared with Jinchengshi, soils in Tangtianshi had higher contents of soil available Ca and Mg, and lower available S. Soils developed from different parent materials had similar content of available Mg, which ranged from 81.5 to 88.2 mg/kg. But soils developed from limestone had the highest content of available Ca with an average value of 2260.3 mg/kg. Soils developed from Quaternary red clay had the highest content of available S (105.0 mg/kg). Land consolidation decreased the content of soil available Ca, and increased soil available Mg and S.2?the soil available Fe and Mn were abundant which has more than 80% of the samples was in high and higher level. Available Zn average contant at 1.0 mg/kg or less and more than 70% of the samples was lack of Zn. Available B was relatively lower because of about 40% of the samples was in critical level and more than 50% of the samples was in low and lower level. Compared with Jinchengshi, soils in Tangtianshi had higher contents of soil available Fe, Cu, Zn and Mo. Soils developed from Quaternary red clay had the lowest content of available Cu, Soils developed from river sediment had the lowest content of available B and Mo, Soils developed from limestone had the lowest content of available Fe, Mn and Zn. Land consolidation decreased the content of soil available Fe, Cu and Zn and increased the content of soil available Mn, B and Mo and also increased the CV value of available Fe, Cu and B.3?In the experimental field was applied to 153.75 kg/hm2 Mg fertilizer, it can make the flue-cured tobacco production increased by 3.4%; tobacco leaf content of TN, nicotine, chlorine and reducing sugar were suitable, content of TK more than 2%, low total sugar content, by applied Ca and Mg could promoted the synthesis of total sugar, ratio of good coordination between the total sugar and nicotion, B fertilizer on K absorption of tobacco have a regulatory role, applied Cu, Mn, B fertilizer could improved the combustion of tobacco; Content soil organic matter and pH of the positive relationship between medium-minor nutrient.4?In the experimental field was applied to 225-450 kg/hm2 slaked lime or 375 kg/hm2 MgCO3 could caused the flue-cured tobacco production increased; In all treatments, tobacco leaf content of TN, nicotine, chlorine and total sugar were suitable, higher K content of the whole in an appropriate range, when applied to the amount of Ca was higher than 675 kg/hm2, tobacco will inhibit the absorption of sugar and total synthesis of chlorine, applied Mg content of less than 75 kg/hm2, will reduce the synthesis of total sugar, and with reduce the amount of Ca and Mg fertilizer, tobacco for TN, TK uptake and nicotine, reducing sugar synthesis has a certain role in promoting, Ca and Mg fertilizer can be applied on tobacco intrinsic chemical composition of each tends to be more coordination; Applied Ca and Mg fertilizer can improve in tobacco planting soils acidic environment, maintain soil exchangeable base was in the appropriate range.Therefore, it is necessary to largely increase Mg, Zn and B fertilizer, and appropriately increase Ca, Zn, Mn and B fertilizer, appropriated to add S fertilizer. In the test area proposed to strengthen the administration of the organic matter, K fertilizer reduce investment. |
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