贵州中部山区植烟土壤有机质含量与海拔和成土母质之间的关系

土壤有机质含量影响着烤烟的产量和品质,与成土母质类型关系密切。本文在贵州中部山区7个烤烟主产县共采集了42个典型烟田耕层多点混合农化样品和来自剖面的165个发生层样品。对土壤有机质含量分析结果表明,贵州中部山区植烟土壤有机质含量的平均值为27.7 g/kg,变幅为24.3~31.6 g/kg,变异系数为9.48%,土壤有机质含量总体处于全国第二次土壤普查肥力评价标准中的三级水平(20~30 g/kg),总体处于植烟适宜水平;贵州中部山区植烟土壤有机质含量与海拔高度呈极显著正相关关系;沟谷堆积物母质发育的土壤有机质含量显著高于第四纪红土和岩类风化残积-坡积物母质发育的土壤;在剖面垂直分布上,土壤有机质含量均表现出较强的表聚性,表现出较明显的从上往下依次递减的规律,不同成土母质发育形成的土壤在相同土层上有机质含量由高到低依次是沟谷堆积物第四纪红土岩类风化残积-坡积物。

Relationship Between SOM Contents of Tobacco Fields and Elevation and Parent Materials in Central Region of Guizhou Province

SOM content affects the yield and quality of flue-cured tobacco. SOM content could be influenced by the soil parent material. 42 surface soil samples and 165 soil profile samples were collected and analyzed from 7 main flue-cured tobacco planting counties in the central region of Guizhou Province. The results showed that SOM content ranged from 24.3g/kg to 31.6g/kg, with a mean of 27.7g/kg and variation coefficient of 9.48%, SOM content was within the 3rd grade in the fertility standard of the 2nd National Soil Survey, suitable for flue-cured tobacco planting. Correlative analysis showed that SOM content was extremely significantly positively correlated with the altitude. The SOM content of soil developed from gully debris was significantly higher than those developed from quaternary red clay and carbonate residual-slope wash. In profile vertical direction, SOM content showed strong surface-aggregation and decreased fast with soil depth. The SOM content of same horizon which formed from different parent material was in an order of gully debris > quaternary red clay > carbonate residue-slope wash.