追施氮肥对盐地碱蓬生长及其改良盐渍土效果研究

为了研究追施氮肥对盐地碱蓬生长及其对盐渍土改良的影响,通过田间小区试验研究了不同追施氮量(0~450 kg/hm²)对盐地碱蓬生长、离子累积以及盐渍土修复的影响。结果表明,追施氮肥能够提高盐地碱蓬茎秆、籽粒和叶片的生物量;在0～450 kg/hm²范围内,盐地碱蓬的各部分生物量均随着追施氮量呈直线增长的趋势。追施氮肥对盐地碱蓬茎秆、籽粒和叶片中的K⁺、Na⁺ 、Ca²⁺、Mg²⁺含量无显著影响,但不同器官不同离子含量之间存在较明显的差异。追施氮肥能够增加盐地碱蓬各部分对K、Na 、Ca、Mg的累积;450 kg/hm²施氮量的盐地碱蓬的各离子累积量均较不施氮显著增加。土壤表层的Na⁺、K⁺含量随着追施氮量增加而降低。总之,追施氮肥能够促进盐地碱蓬对盐渍土的生物修复,降低土壤中的Na⁺浓度及其危害。

Effect of nitrogen topdressing on the growth of Suaeda salsa and the improvement of saline soil

The effects of topdressing different nitrogen levels on the growth of Suaeda salsa and on the improvement of saline soil, were conducted in field experiments where growth, accumulative amounts of K⁺, Na⁺, Ca²⁺, and Mg²⁺ of S. salsa, as well as salinity concentrations in soils were assessed. The yields of grain, stem, leaf and biomass increased with N topdressing. At the rate of 450 kg/ha, the biomass of component factors in S. salsa presented a linear growth trend with the amount of N topdressing. With a further increase of nitrogen application, the concentrations of K⁺, Na⁺, Ca²⁺, and Mg²⁺ barely changed. The accumulative amounts of K⁺, Na⁺, Ca²⁺, and Mg²⁺ increased with N topdressing. The concentrations of K⁺ and Na⁺ in surface soils (0-10 cm) showed decreasing trends with N topdressing. N fertilisation could therefore stimulate S. salsa growth and strengthen the effectiveness of bioremediation of saline soil.