摘 要 ：本文对松嫩平原盐碱化草地生长的5种耐盐牧草羊草(Aneurolepidium chinense)、星星草(Puccinelia tenuiflora)、虎尾草(Chloris virgata)、獐茅(Aeluropus littoralis var. sinensis)和碱蓬(Suaeda glauca)体内K+、Na+的积累与分布动态进行研究。结果表明，植物体内含量Na+μmol／克干重，碱蓬最高为5419—5668，其次是獐毛为225—326和星星草为177—216，虎尾草和羊草变化较大，分别为20—699和11—217。体内Na+含量受土壤中Na+水平的影响。Na+／K+以碱蓬最大为10.47—25.74。随着土壤盐含量(x1)、pH(x2)的增加，羊草和虎尾草体内Na+μmol／克干重(Y)积累动态符合公式：Y=Ym/[1+e(a+b1x1+b2x2)]，碱蓬、星星草獐毛符合公式Y=a+b1x1+b2x2。植物体内Na+的积累率依次为：虎尾章>羊草>星星草、獐毛和碱蓬。K+主要分布在代谢旺盛的幼嫩组织中。茎叶是Na+的主要积累部位。虎尾草各部位Na+的积累率均呈显著增大，同时K+均降低，碱蓬各部位K+积累率均随Na+积累而增大。
Abstract:The patterns of accumulation and distribution of K+ and Na+ in the tissues of Aneurolepidium chinense(Kitag), Puccinellia tenuiflora (Scribn. et Merr.), Chloris virgata (SW.), Aelirepus litoralis var. sinensis and Suaeda glauca (Bunge) in a saline grassland of Song-Nen Plain were discussed. The results showed that S. glauca had the highest Na+ concentration (5,491.0μmol Na/g dw), followed by A. litoralis and P. tenuiflora which had 225.85 and 177.7μmol Na/g. dw, respectively. The lowest levels were found in A. chinense and C. virgata which contained 20.2 and ll.31μmol Na/g. dw, respectively. The Na+ content of these species was correlated with the levels of Na+ in the soil. The Na/K ratio was highest in S. glauca (25.74) and lowest in C. virgata(0.028).The sodium accumulation (y=μmol Na/g dw) in A. chinense and C. virgata could be best described by an equation y=Ym/[-1+e(a+b1x1+b2x2)], where x1 is the soil salt content and x2 is the soil PH. In S. glauca, P. tenuiflora and A. litoralis, the Na+ accumulation was described by the equation y = a + b1x1 +b2x2. The Na+ accumulation rate, which was defined as the % increase in the Na+ concentration in the tissues of grass for every 0.1% increase in the soil salt content, followed the order of C. virgata>A. chinense>P. tenuiflora, A. Litoralis var. sinensis and S. glauca. The younger tissues, having a more active metabolism, were found to be the major sinks of accumulated Na+ with increasing soil salinity. The Na+ accumulation rate in C. virgata was markedly increased in different plant tissues, while K+ content decreased with the increase in the Na+ accumulation rate. However, in S. glauca the rate of K+ accumulation increased with the increased in the rate of Na+ accumulation.