塔里木河下游新生林地滴灌下土壤盐分分布特征研究

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)。

Characteristics of Soil Salt Distribution under Different Distance of Irrigation Emitter in Young-aged Forest in the Lower Reaches of Tarim River

This paper takes young-aged forest of the transitional zone of oasis-desert as an example,which located company 8 mission 35 regiment in the lower reaches of Tarim River.We analyzed the charateristics of soil salt distribution under different distance of irrigation emitter,24 hours after irrigation.The results show that: ① In a horizontal direction,for 3 m distance of irrigation emitter,the section of high salt concentration appear in the soil profile at the point of 75 cm whose salt concentrations correlated significantly positively to that of 60 cm point,with the decrease of distance from irrigation emitter,the relationship is reduced;for 1 m distance of irrigation emitter,the section of high salt concentration appear in the soil profile of 45 cm point whose salt concentrations correlated significantly positively to any other soil profile.Under both the 3 m and the 1 m distance of irrigation emitter,the salt distribution of soil profile of 45 cm point is uniformly,the coefficient of variation were 24%、28% respectively.And in the soil layer which is closed to irrigation emitter,the soil salt distributed uniformly,the coefficient of variation were 68%、68% respectively.② In a vertical direction,the soil layer of 40～60 cm is the salt collective zone either at a distance of 3 m irrigation emitter or at a distance of 1 m irrigation emitter.Under the distance of 3 m irrigation emitter,the relationship between the salinity of the soil layer of 40～60 cm has prominent negative correlation with other soil layers.Soil salinity in the middle and lower layer distributed uniformly,and distributed unevenly when close to upper soil layer,under the two kinds of distance of irrigation emitter,coefficient of variation of soil salinity of middle and lower layer were all small(≤11.28%),and of the upper surface layer were large(≥60.4%).③ Under the action of a particular huge evaporativity,the soil salt could have come to the bottom focused at the 50 cm depths(for the distance of 3 m) and the 65 cm depth(for the distance of 1 m).