【摘要】 用５种实验方法对东北草原区２３３种植物光合类型进行鉴定，并对其相对分布 随纬度变化关系及其与土壤含盐量和ＰＨ值的关系进行分析．在此基础上对几种典型Ｃ３、 Ｃ４牧草适应于盐碱环境的生理特点进行深入研究结果表明，在所鉴定的２３３种植物中， Ｃ３植物有 １４４种，隶属于 ２８科 ９４属，Ｃ４植物有 ８９种；隶属于 １７科 ５５属，在高纬度地区 Ｃ３植物表现出更高的生长优势，在纬度较低和盐碱化区域，Ｃ４植物分布具相对优势．尤其 在盐碱化程度较重的地区，Ｃ４植物成为明显的优势种，分布上的差别决定于它们对环境 适应机制上的差异Ｃ３植物对盐碱环境适应机制主要通过积累脯氨酸等有机溶质进行渗 透调节，而Ｃ４植物主要通过液泡中离子区域化积累作用进行调节，并且与Ｃ３植物相比对 盐碱环境具更强的适应能力．更多还原

【Abstract】 In this article, the photosynthetic types of 233 plant species in Northeastern China prairie area were indentified, and the relationships of their relative distribution with latitude, soil salt content and soil pH value were analyzed. A further study of physiological adaptation of several typical C3 and C4 grasses to saline-alkali environment was conducted. The result shows that among the identified 233 species, 144 species are C3 plants, belonging to 94 genera of 28 families. and 89 species are C4 plants, belonging to 55 genera o[ 17 [amities. At high latitude districts, C3 plants show a higher growth dominance. but al low latitude and saline-alkali districts, C4 plants show a relatively dominant distribution, and especially in severely saline-alkali districts, C4 plants become evidently dominant species. Tile difference of plant distribution depends on its adaptation mechanism to the saline-alkali environment: C3 plants conduct a penetrative regulation through their accumulation of proline and other organic solutes, and C4 plants do this through the accumulation of intra-vocuole ions. Compared with C3 plants, C4 plants show a better adapting capability to tile saline-alkali environment.更多还原