四川会东植烟土壤盐分离子评价

Evaluation on salt ions of tobacco-growing soil in Huidong County of Sichuan Province

采集四川省凉山州会东县的103个植烟土壤样品,测定了0~20 cm土壤的盐分离子质量浓度,系统分析了不同海拔及茬口对植烟土壤盐分离子质量分数的影响。结果表明,采样区植烟土壤均为非盐渍化土,含盐量为0.12~0.70 g·kg^(-1),平均含盐量为0.26 g·kg^(-1),为中等强度变异。土壤中各盐分离子与总含盐量之间的相关性表现为HCO_(3)^(-)和K^(+)达显著性正相关(P<0.05),SO_4^(2-)呈极显著性正相关(P<0.01)。不同海拔植烟土壤中阴离子主要以HCO_(3)^(-)和SO_4^(2-)为主,其中SO_4^(2-)占比较大;阳离子则主要以K^(+)和Ca^(2+)为主。不同茬口种植方式下植烟土壤盐分离子的结果表明,通过前茬作物种植能有效降低植烟土壤中Cl^(-)的质量分数,增加HCO_(3)^(-)的占比频率,同时提升土壤中K^(+),Na^(+)和Ca^(2+)的质量分数。综合来看,本研究区域中植烟土壤未达盐渍化水平,但土壤中的SO_4^(2-)和HCO_(3)^(-)质量分数过高,可能会破坏植烟土壤中阴阳离子平衡,从而抑制烤烟生长,降低烟叶品质。因此,该地区在植烟土壤改良时应关注SO_4^(2-)和HCO_(3)^(-)质量分数的变化。

In this study,103 soil samples were collected from Huidong County,Liangshan prefecture,Sichuan Province.The contents of salt and salt ions in 0-20 cm soil were determined.The effects of different altitudes and crop rotation on salt content and salt ions content of tobacco-growing soil were systematically analyzed.The results showed that the tobacco-growing soils of the sampling area were all non-salinization soil,with the salt content of 0.12~0.70 g·kg^(-1) and the average salt content of 0.26 g·kg^(-1),which was a medium intensity variation.The correlation between each salt ion and total salt content in soil showed a significant positive correlation between total salt content and HCO_(3)^(-) or K^(+)(P<0.05),and an extremely significant positive correlation between total salt content and SO_4^(2-)(P<0.01).The HCO_(3)^(-) and SO_4^(2-) were the main anions at different altitudes in tobacco-growing soil,where SO_4^(2-) accounted for the larger proportion,while K^(+)and Ca2^(+)were the main cations.Different stubble planting methods also have effect on salt ions in tobacco-growing soil.The previous crop planting can effectively reduce the content of Cl^(-)in tobacco-growing soil,increase the proportion frequency of HCO_(3)^(-),and meanwhile increase the mass concentrations of K^(+),Na^(+)and Ca2^(+)in soil.Generally speaking,this area did not reach the salinization level in tobacco-growing soil,but the mass concentrations of SO_4^(2-) and HCO_(3)^(-) were too high in the soil,which may destroy the balance of cation and anion in soil,and thus may inhibit the growth of flue-cured tobacco and reduce the quality of tobacco.Therefore,we should pay attention to the changes of SO_4^(2-) and HCO_(3)^(-) mass concentrations in the process of tobaccogrowing soil improvement.