东北草原区C3、C4植物的生态分布及其适应盐碱环境的生理特性

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.

Ecological distribution and physiological adaptation to saline-alkali environment of C3 and C4 plants in Northeastern China prairie area

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 pHvalue were analyzed. Afurther 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 of 17 famities. 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.