氮肥对盐角草生长及矿质灰分累积的影响

Effects of N fertilization on growth,mineral ash absorption and accumulation of Salicornia europaea L.

在新疆南疆重盐化土壤上采用田间试验方法及完全随机区组设计,研究了不同氮肥施用水平(0、75、150和225 kg/hm2)对盐角草生长以及矿质灰分吸收累积的影响。结果表明,施用氮肥能显著提高盐角草的地上部各部分生物量、根系干重、种子产量及总灰分累积量,其中施用225 kg/hm2氮肥时,盐角草每年可从土壤中带走8 435.1 kg/hm2矿质灰分,为不施氮肥的4.28倍,而且地上部生物量、根系干重、种子产量也分别比未施氮肥处理高4.02、4.72和2.84倍,施肥效果均达显著水平;施用氮肥可显著提高盐角草同化枝和种子中的氮含量,但对茎秆氮含量无显著影响,对盐角草磷含量的影响因器官不同而有所差异;施用氮肥可以在一定程度上提高盐角草茎秆、同化枝以及全株的矿质灰分含量,对增强盐角草的耐盐能力有益。总体来看,氮肥的合理施用对于促进盐角草的生长,吸盐能力的提高效果显著,加强氮素养分管理在应用盐角草改良盐碱地过程中有着重要的作用。

Research was carried out in the hope of restoring the saline land rapidly and effectively through improving halophytes＇biomass and performance by applying nitrogen fertilizer in saline areas.Effects of various levels of nitrogen fertilization（0,75,150 and 225 kg/hm2） on growth,mineral ash absorption and accumulation of Salicornia europaea L.were studied through complete randomized block design under the saline field condition in Xinjiang.The results indicated that the aerial biomass,the root dry weight,the seed yield and the mineral ash cumulant increased significantly with increasing N levels.Among different nitrogen treatments,the highest ash cumulant absorbed by Salicornia europaea L.was N3（225 kg/hm2）,with 8 435.06 kg/hm2 being the figure recorded,which was 4.28 times of CK.Meanwhile,N3（225 kg/hm2） also claimed the highest aerial biomass,root dry weight and seed yield which were 4.02,4.72 and 2.84 times of CK,respectively.Furthermore,compared with CK,applying nitrogen can improve nitrogen concentration in shoot and seed of Salicornia europaea significantly when nitrogen level was up to 225 kg/hm2,however,no significant difference in nitrogen concentration in stem and phosphorus concentration in all the three plant organs listed above were noted among different nitrogen levels.The effect of nitrogen on phosphorus concentration in Salicornia europaea is varying which mainly depends on the specific part.Although mineral ash concentration in assimilation shoot and stem were increased to some extent by nitrogen application,yet the difference was not significant.The results suggest that under the saline land condition,nitrogen can significantly promote Salicornia europaea＇s growth and mineral ash absorption and,as a result,strengthening nitrogen management is very important in the process of saline land restoration by planting Salicornia europaea.