盐生植物对重盐渍土脱盐效果

Desalination Effect of Halophytes in Heavily Salinized Soil of Karamay,Xinjiang,China

以新疆克拉玛依农业综合开发区新垦重盐渍土为研究对象,在滴灌条件下开展了盐生植物盐角草（Salicornia europaea）、盐地碱蓬（Suaeda salsa）和裸地（对照）处理的试验,通过测定植物地上生物量及植株和土壤中K＋、Na＋、Ca2＋、Mg2＋、Cl-和SO2-4含量及土壤总盐含量,评估种植盐生植物对重盐渍土盐分的影响。结果表明：灌溉条件下,盐角草和盐地碱蓬地上生物量分别为11 044.37kg·hm-2和19 119.26kg·hm-2,刈割后地上部分灰分盐分别为4 709.98kg·hm-2和5 184.96kg·hm-2;与种植期前相比,种植期后盐角草、盐地碱蓬和对照处理0~30cm土层总盐分别下降了55.62%、32.98%和20.79%,盐角草和盐地碱蓬处理下降幅度均高于对照,30~60cm土层盐角草和盐地碱蓬处理土壤总盐分别下降了21.82%和29.16%,而对照却上升了18.31%;盐角草和盐地碱蓬均对Na＋、Cl-和SO2-4具有较强的摄取能力,尤其是对Cl-表现出更强的选择吸收倾向;盐角草和盐地碱蓬SO2-4含量基本相当,但盐角草Na＋和Cl-含量分别是盐地碱蓬的2.33倍和2.22倍,盐角草对于Na＋和Cl-的强积聚特征使其更适于对氯化物盐渍土的改良。在盐渍荒漠新垦地种植盐生植物,土壤脱盐效果明显。

The effect of salt-resistant plants on improving heavily salinized soil and reducing salt content in the tillage layer was evaluated in the newly cultivated, saline land in the Karamay Agricultural Development Region, Xingjiang, China. Annual halophytes--Salicornia europaea and Suaeda salsa were grown under drip irrigation, and then above-ground plant biomass, content of K＋ , Na＋ , Ca2＋ , Mg2＋ , C1- and SO2~ , and total salt content in soil were determined. The results indicated that under irrigation conditions, biomass of S. europaea and S. salsa was 11 044.37 kg.hm 2 and 19 119.26 kg.hm 2 respectively, and ash-free salt content of above-ground plant parts was 4 709.98 kg. hm-2 and 5 184.96 kg. hm-2, respectively. After har- vest, total salt content in 0-30 cm soil layer of treatment of S. europgea, S. salsa and the bare land de- creased by 55.62%, 32.98% and 20.79%, respectively; and that in 30-60 cm soil layer of treatment of S. europaea, S. salsa decreased by 21.82% and 29.16% respectively, while the control increased by 18.31%. S. egropaea and S. salsa showed strong uptake capacity to Na＋, C1- and SO24- , especially for C1-. Although the content of SO2/4- in both plants was equal, the content of Na＋ and C1- in S. europaea was 2.33 times and 2.22 times that in S. salsa, respectively. The ability of S europaea to accumulate more Na＋ and CI- made it a better choice for reducing chloride salt in soil. Our study suggested that planting salt- resistant plants could have significant desalination effects on soil in newly cultivated land in a saline desert.