Spatial distribution characteristics of soil nutrients and fertility evaluation in tobacco-growing areas of south subtropics,Yunnan province
[Objective]The paper aimed to clarify the spatial distribution characteristics of soil nutrient content and storage and its fertility status in tobacco-growing area of south subtropics,Yunnan province.[Method]Taking 3033 tobacco planting soil samples from this region in 2019-2022 as the study object,the spatial changes and influencing factors of nutrients in the cultivated layer under different soils and geo-morphic types were analyzed,and the soil fertility level and spatial distribution in tobacco-growing area were quantified by the GIS and fuzzy comprehensive evaluation method.[Result]There were significant spatial differences in soil nutrient content and storage in tobacco-growing area in main climate types of south subtropics,Yunnan province.The nutrient contents in the topsoil of yellow-brown soil were better than of other soil types,and the nutrient contents in the dam area and the hilly area were significantly higher than those in the mountainous area.O-verall,the average contents of soil organic matter(SOM),total nitrogen(TN),available phosphorus(AP),available potassium(AK)and slow-acting potassium(SAK)were 29.68±18.99 g/kg,1.28±0.85 g/kg,30.90±32.03 mg/kg,178.38±138.18 mg/kg,and 406.78±467.52 mg/kg,respectively,and the average storages were 96.54±111.11,4.03±3.50,0.11±0.15,0.60±0.72,and 1.35±1.82 t/hm2,respectively.The areas with high nutrient storages were mainly distributed in counties such as Shiping,Jianshui,Kaiyuan,Gejiu in Honghe prefecture and Dehong prefecture.Longitude and latitude,altitude,topsoil thickness,effective soil layer thickness,content and storage of SOM,and soil bulk density were important factors that affected the spatial changes of soil nutrient content and storage.The overall content of SOM,TN,AP and AK in the soil was relatively high in tobacco-growing area in main climate types of south subtropics,with 72.0％ ,64.2％ ,73.2％ and 68.0％ of the sampling points with abundance and deficiency levels above the high level,respectively.The overall pH of the soil was acidic,with acidic soil accounting for 84.2％ .The fuzzy evaluation results showed that the proportion of soil fertility in the Ⅰ-Ⅴ level was 15.0％ ,31.0％ ,30.0％ ,21.0％ and 3.0％ ,respectively,showing a good overall trend.The low value areas of soil fertility were mainly concentrated in main climate types of south subtropics in Honghe prefecture,and the higher soil fertility areas were mainly concentrated in the north,west and southwest of the study area.[Conclusion]The proportion of soil fertility suitable for tobacco planting in the subtropical cli-mate region of Yunnan is moderate,and the overall soil fertility in the eastern part of the study area needs to be improved.It is also necessary to reduce the application of acidic fertilizers,adopt a reasonable combination of organic and inorganic fertilizers,and prevent soil erosion in farmland in the study area.
South subtropical climateTobacco-growing areaSoil nutrient contentSoil nutrient storageSoil fertility
万方数据
维普
