不同灌水处理对滨海盐碱地土壤阳离子组成及玉米干物质累积的影响

Effects of different irrigation treatments on cationic composition of soil and dry matter accumulation of maize in coastal saline-alkali area

采用田间试验对不同灌水处理灌水后玉米地(天津滨海盐碱地)0~60 cm土层土壤K^+/Na^+、Ca^2+/Na^+及玉米干物质累积量进行研究,共设计4个处理,分别为LI10(常规滴灌,灌水10 mm)、LI20(常规滴灌,灌水20 mm)、FI10(膜下滴灌,灌水10 mm)和FI20(膜下滴灌,灌水20 mm)。结果表明:灌水后不同灌水方式下灌水量较大的处理0~60 cm各土层K^+/Na^+均大于灌水量较小的处理,且均表现出0~20 cm土层K^+/Na^+较大,40~60 cm土层K^+/Na^+较小;相同灌水量下膜下滴灌处理0~60 cm各土层Ca^2+/Na^+均较大,灌水后不同灌水处理0~60 cm各土层Ca^2+/Na^+差异较小,变化范围为0.10~0.22;FI20处理0~20 cm土层K^+/Na^+和Ca^2+/Na^+大于其他处理,分别达到0.78和0.22;随着灌水次数的增多,LI20和FI10处理0~20 cm土层K^+/Na^+和Ca^2+/Na^+均逐渐增大,LI10处理则均逐渐减小;灌水后各处理之间0~60 cm各土层K^+/Na^+和Ca^2+/Na^+差异均达显著水平;全生育期干物质累积量与其对应的0~20 cm土层(K^+/Na^+)/Ca^2+二次拟合相关系数均达0.90以上,相同(K^+/Na^+)/Ca^2+下,FI20处理干物质累积量始终最大,LI10处理始终最小;(K^+/Na^+)/Ca^2+>1.72时,各处理干物质累积量均随(K^+/Na^+)/Ca^2+的增大而增大。

In order to investigate the effects of different irrigation treatments on the soil cation composition of the coastal saline-alkali land in Tianjin,a field experiment was carried out to investigate the variation of K^+/Na^+,Ca^2+/Na^+in the 0~60 cm soil and dry biomass accumulation in maize after irrigation.Four different treatments were designed,LI10(conventional drip irrigation,10 mm),LI20(conventional drip irrigation,20 mm),FI10(drip irrigation under mulch,10 mm),and FI20(drip irrigation under mulch,20 mm),respectively.The results showed that the K^+/Na^+in 0~60 cm soil layer with higher irrigation amount were higher than those with lower irrigation amount under different irrigation treatments.The K^+/Na^+in the 0~20 cm soil layer was greater,while the K^+/Na^+in the 40~60 cm soil layer was lower.The Ca^2+/Na^+ratio was higher in all soil layers of 0~60 cm under mulch drip irrigation with the same irrigation amount,while there was no significant difference among all soil layers of 0~60 cm under different irrigation treatments,with a range of 0.10~0.22.The ratios of K^+/Na^+and Ca^2+/Na^+in 0~20 cm soil layer treated with FI20 were much higher than those in other treatments,reaching 0.78 and 0.22,respectively.With increasing irrigation times,K^+/Na^+and Ca^2+/Na^+in 0~20 cm soil layer treated with LI20 and FI10 were gradually increased,while the treatment with LI10 gradually decreased.After irrigation,K^+/Na^+and Ca^2+/Na^+differences in 0~60 cm soil layers reached significant levels.The dry biomass accumulation in the whole growth period and the correlation coefficient of the 0~20 cm soil layer(K^+/Na^+)/Ca^2+secondary fitting were all above 0.90,under the same(K^+/Na^+)/Ca^2+condition,the dry matter accumulation in FI20 treatment always reached the maximum and that in LI10 treatment was always at the minimum.When(K^+/Na^+)/Ca^2+>1.72,the dry matter accumulation of each treatment increased with the increase in(K^+/Na^+)/Ca^2+.