重庆市万州植烟区土壤养分现状及施肥区划

Evaluation of Soil Nutrient Abundance and Deficiency in Wanzhou Tobacco-Growing Area of Chongqing

万州烟田土壤养分空间变异较大,且缺乏系统研究,制约了万州烟业的发展.为了全面掌握万州区烟田土壤养分现状,2021年选取该区5个乡镇中具有代表性的种植单元土样进行分析,得出该区土壤养分现状,并进行施肥区划及提出相应的施肥方案.结果表明,万州植烟区土壤pH平均值为5.32,75%的土壤呈酸性,酸化较为严重.万州植烟区土壤有机质、碱解氮、有效磷、速效钾、交换性钙和交换性镁适宜的比例分别为30.4%,52.7%,27.6%,25.9%,32.1%和38.7%,从当前烟田土壤养分情况看,土壤有机质较为丰富,碱解氮供应能力良好,有效磷总体适中,速效钾整体偏高.万州植烟区土壤有效铁、有效锰较高,有效锌大多处于适宜范围,土壤有效铜、有效硼、有效钼和水溶性氯缺乏,且各元素空间分布不均.万州植烟区土壤pH值影响土壤交换性钙、镁,进而显著影响土壤阳离子交换量.重庆市万州植烟区应采取“降酸、增碳氮、调磷、减钾、补微”的措施,以土壤养分测定结果为依据,根据施肥区划图,在施肥过程中结合具体区域与地块,科学合理地提出各区域的施肥管理方案,为万州区烤烟产业持续发展提供科学参考方案.

The spatial variation of soil nutrients in Wanzhou tobacco fields is large,and the lack of systematic research restricts the development of Wanzhou tobacco industry.In order to fully grasp the current situation of soil nutrients in tobacco fields in Wanzhou District,in 2021,representative soil samples of planting units in 5 townships in the district were selected for analysis.The current situation of soil nutrients in the district was obtained,and fertilization divisions were carried out and corresponding fertilization plans were proposed.The results showed that the average soil pH in Wanzhou tobacco-growing area was 5.32,and 75%of the soil was acidic,and the soil acidification was serious.The suitable proportions of soil organic matter,alkali-hydrolyzed nitrogen,available phosphorus,available potassium,exchangeable calcium and exchangeable magnesium in Wanzhou tobacco planting area were 30.4%,52.7%,27.6%,25.9%,32.1%and 38.7%,respectively.In terms of soil nutrients,the soil organic matter is relatively rich,the supply capacity of alkaline hydrolyzable nitrogen is good,the available phosphorus is generally moderate,and the available potassium is generally high.Soil available iron and manganese in Wanzhou tobacco planting area are high,and the effective zinc is in the suitable range with a high percentage soil available copper,available boron,available molybdenum and water-soluble chlorine are deficient.The spatial distribution of each element is uneven.Soil pH in Wanzhou tobacco-growing area affects soil exchangeable calcium and magnesium,which in turn significantly affects soil cation exchange capacity.Therefore,the Wanzhou tobacco planting area of Chongqing City should take the measures of“reducing acid,increasing carbon and nitrogen,adjusting phosphorus,reducing potassium,and supplementing micronutrients”.Based on the results of soil nutrient determination,according to the fertilization zoning map,the fertilization process should be based on the specific areas and plots to put forward scientific and reasonable fertilization scheme of each region.This study provided a scientific reference plan for the sustainable development of the flue-cured tobacco industry in Wanzhou District.