不同地下水埋深对龟裂碱土水盐迁移和油葵产量的影响研究

Research on the Influence of Different Groundwater Depth on Water-salt Migration and Oil Sunflower Yield in Takyric Solonetz Land

为探讨龟裂碱土不同地下水埋深对土壤水盐迁移的影响及其变化特征,对宁夏银北前进农场龟裂碱土试验区0.8、1.0、1.2、1.5、1.8和2.0 m共6种地下水埋深下的土壤含盐量、含水率、地下水矿化度进行了原位监测,结果表明:土壤全盐与地下水埋深呈指数关系,土壤全盐与地下水矿化度呈明显的线性正相关。土层0~100 cm土壤不同地下水埋深条件下土壤全盐和碱化度变化为0.8 m>1.0 m>1.5 m>1.8 m>2.0 m;1.5 m地下水埋深是土壤水盐变化的转折点,地下水埋深0.8~1.2 m下各土层的全盐和含水率均较高。地下水埋深1.5~1.8 m土壤水盐变化较小。地下水埋深0.8、1.0和1.2 m的田块油葵出苗率、成活率、株高、茎粗、盘径和产量显著低于地下水埋深1.5、1.8和2.0 m的田块油葵。油葵适宜在地下水埋深1.5~2.0 m生长,地下水埋深1.5、1.8和2.0 m的土壤含水率、全盐和碱化度以及油葵出苗率、成活率、株高、茎粗、盘径和产量之间无显著差异。结果为龟裂碱土改良水盐调控提供依据,以及对干旱地区的环境保护和农业灌溉的发展具有重要的科学价值。

In order to study the effect of different groundwater depth on soil water and salt transport and its changing characteristics in takyric solonetz soil,the salt content,water content and salinity of the soil under six groundwater depths of 0.8,1.0,1.2,1.5,1.8 and 2.0 m are monitored in takyric solonetz land at the farmland of Xidatan in Ningxia,China.The results show that there is an exponential relationship between soil total salt and groundwater depth,and there is a significant linear positive correlation between soil total salt and groundwater salinity.The change of total salinity and alkalinity is 0.8 m>1.0 m>1.5m>1.8m>2.0 m;1.5 m ground water depth is the turning point of soil water and salt change.The total salt and water content of each soil layer are higher at 0.8~1.2 m ground water depth.The variation of soil water and salt is the most serious in the soil with the groundwater depth of 1.5~1.8 m.Oil sunflower grows in 1.5~2.0 m depth of ground water suitably.The emergence rate,survival rate,plant height,stem diameter,diameter and yield of oil sunflower in 0.8,1.0 and 1.2 m of groundwater table are significantly lower than those in 1.5,1.8 and 2.0 m of groundwater table.There are no significant differences in soil water content,total salinity and alkalinity,emergence rate,survival rate,plant height,stem diameter,disc diameter and yield of oil sunflower at depths of 1.5,1.8 and 2.0 m.These results will provide a technical support for salt-water management of the takyric solonetz farmlands,and have an important scientific value for environmental protection and agricultural irrigation development in arid areas.