几种一年生盐生植物的吸盐能力

【目的】土壤盐渍化在新疆发生面积多,分布广,利用盐生植物对盐分的超富集能力,选育生物量大且体内盐分浓度高的品种,可有效改良盐碱地。本试验比较了几种主要盐生植物的吸收离子类型和盐分积累量,为科学合理利用盐生植物进行盐碱地改良提供科学依据。【方法】选取一年生盐角草(Salicornia europaea)、盐地碱蓬(Suaeda salsa)、高碱蓬(Suaeda altissima)和野榆钱菠菜(Atripex aucheri Moq.)为材料进行人工种植,试验地土壤为壤土和砂壤土,耕层土壤盐分均值为10.23 g/kg,p H为8.36,属于中度盐化土壤。采用完全随机排列设计,在生育早期、中期和末期采样测定植物地上、地下部分干物质量和K+、Na+、Ca2+、Mg2+、Cl-、SO2-4浓度。【结果】生育末期四种盐生植物地上生物量均占整株生物量的89%以上,高碱蓬(23302 kg/hm2)蓬野榆钱菠菜(20379 kg/hm2)盐地碱蓬(18670 kg/hm2)盐角草(9096 kg/hm2)。盐分总浓度盐角草(215 g/kg)盐地碱蓬(152 g/kg)高碱蓬(137 g/kg)野榆钱菠菜(103 g/kg)。不同植物离子含量不同,K+浓度以高碱蓬中最高,Na+、Cl-、SO2-4在盐角草中最高,Ca2+、Mg2+浓度在盐地碱蓬中最高;4种盐生植物对Na+、Cl-、SO2-4的吸收能力极强,按阴离子类型划分盐角草属于SO2-4-Cl-型盐生植物,盐地碱蓬、高碱蓬、野榆钱菠菜属于Cl--SO2-4型盐生植物;盐分积累量为高碱蓬(3499 kg/hm2)盐地碱蓬(3061 kg/hm2)蓬野榆钱菠菜(2180 kg/hm2)盐角草(2080 kg/hm2)。【结论】盐生植物对土壤的改良效果主要以生育末期刈割时单位面积从土壤中吸收的盐分总量来衡量,这取决于此时地上部分生物量与植株体内盐分浓度的大小。植物会根据其生长需求选择吸收土壤中矿物质元素,盐角草对的Na+、Cl-的吸收能力强于盐地碱蓬、高碱蓬和野榆钱菠菜,尤其对Cl-表现出极强的选择吸收能力。

Salt absorption capacities of several annul halophytes

【Objectives】 Soil salinization happens in large area in Xinjiang, China. Cultivation of halophytes is one of the main remediation ways of the salty soils. The study on their capabilities to absorb salt and ions will provide base for choosing correct halophytes in Xinjigan.【Methods】 A field experiment was conducted in saline-alkali soil, and annual halophytes Salicornia europaea,Suaeda salsa, Suaeda altissima and Atripex aucheri Moq. were planted. The soils are loam and sandy, in which the average total salt content are 10.23 g/kg, pH 8.36, belonging to middle salinization. The contents of K⁺, Na⁺, Ca²⁺, Mg²⁺, Cl^- and SO^2-₄ and total salt in above and under ground parts were measured in early, mid and late growth of the halophytes. 【Results】 The above-ground biomass of the four halophytes in the late growth period is in the order of Suaeda altissima(23302 kg/ha)＞Atripex aucheri Moq.(20379 kg/ha)＞Suaeda salsa(18670 kg/ha)＞Salicornia europaea(9096 kg/ha), averaged more than 89% of the total dry matter. The order for salt content is Salicornia europaea(215 g/kg)＞Suaeda salsa(152 g/kg)＞Suaeda altissima(137 g/kg)＞Atripex aucheri Moq.(103 g/kg). K⁺ content of Suaeda altissima, Na⁺,Cl^-,SO^2-₄ contents of Salicornia europaea as well as the Ca²⁺,Mg²⁺ contents of Suaeda salsa are the highest. All the four types of halophytes have a strong absorptive capacity for Na⁺、Cl^-、SO^2-₄.Salicornia europaea belongs toSO^2-₄- Cl^- type halophytes and Suaeda salsa, Suaeda altissima, Atripex aucheri Moq. are Cl^-- SO^2-₄ type halophytes, according to anion type. The order of salt accumulation is Suaeda altissima(3499 kg/ha)＞Suaeda salsa(3061 kg/ha)＞Atripex aucheri Moq.(2180 kg/ha)＞Salicornia europaea(2080 kg/ha). 【Conclusions】The halophyte’s capability on improving saline soil mainly depends on the accumulated amount of salts and the total biomass of the plant. Among the halophytes tested, Salicornia europaea showed the highest uptake capacity to Na⁺、Cl^- than the other three ones.