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以塔里木河下游35团8连绿洲-荒漠交界处滴灌条件下的新生林地为研究对象,对滴灌结束24 h后不同滴头间距下的土壤盐分分布特征进行了分析,结果显示①水平方向上,在3 m滴头间距下出现盐峰是在75 cm点处的土壤剖面,这一剖面与60 cm点处的土壤剖面盐分在0.01水平上呈显著相关,随着距滴头距离的减小相关性递减;在1 m滴头间距下出现盐峰是在45 cm点处的土层,这一土层与各点处的土壤剖面盐分在0.01水平上呈显著相关;无论在3 m滴头间距下还是在1 m滴头间距下,45 cm点处的土壤剖面盐分分布较均匀,离滴头越近的土壤剖面盐分分布越不均匀。②垂直方向上,无论是在3 m滴头间距下还是在1 m滴头间距下,40~60 cm的土层是盐分聚集区。在3 m滴头间距下,40~60 cm的土层盐分与各土层间的相关系数均未达显著相关水平;在1 m滴头间距下,40~60 cm的土层盐分与其它各土层间均为负相关关系;无论是在3 m滴头间距下还是在1 m滴头间距下,中下层土壤盐分分布较均匀,而越接近表层的土壤盐分分布越不均匀,在2种滴头间距下,中下层土壤盐分变异系数都较小,表层土壤变异系数较大。③在研究区特殊的强蒸发力下,原本可到达底部土层的盐分在毛管作用下随着水分向上运动,最终导致了盐分聚集于50 cm深度处(3 m滴头间距)与65 cm深度处(1 m滴头间距)。
The distribution of soil salinity under different dripper spacing 24 h after the end of drip irrigation was studied using the new-born woodland under the condition of drip irrigation at the 8th-8th oasis-desert junction in the lower reaches of the Tarim River. The results showed that ① in the horizontal direction, The presence of a salt peak at a 3 m dripper spacing is a soil profile at 75 cm, which is significantly correlated with the soil profile salinity at the 60 cm point at the 0.01 level, with decreasing distance from the dripper The salt peak at 45 cm drip distance at 1 m dripper spacing was significantly correlated with the soil salinity at each point at the 0.01 level. No matter at 3 m dripper spacing Under the 1 m dripper spacing, the profile of soil salt at 45 cm is more evenly distributed and the closer the soil profile to the dripper, the more uneven the salinity distribution is. ② In the vertical direction, the soil layer of 40 ~ 60 cm is the salt concentration area under the 3 m dripper spacing or the 1 m dripper spacing. Under 3 m dripper spacing, the correlation coefficient between the salt content of 40-60 cm soil layer and each soil layer did not reach the significant correlation level. Under the 1 m dripper spacing, the soil salt content of 40-60 cm soil layer and other Soil layers are negatively correlated; under the 3 m drip spacing or 1 m dripper spacing, the soil salt distribution in the middle and lower layers is more uniform, and the closer the soil salt distribution in the surface layer is, Under the dripper spacing, the coefficient of variation of soil salinity in the middle and lower layers was smaller, and the coefficient of variation of surface soil was larger. (3) Under the special strong evaporation force in the study area, the salt which could reach the bottom soil layer moves upward along with water under the action of capillary tube, finally resulting in salt concentration at 50 cm depth (3 m dripper spacing) and 65 cm depth Department (1 m dripper spacing).