The populations of the exotic plant species Spartina alterniflora competed with native plant species Phragmites australis in the intertidal habitats of Dongtan wetland, Chongming, Shanghai. The spatial and temporal characteristics of non-structural carbohydrates ( NSC) contents of different parts of P. australis and S. alternijlora plants were studied. The results showed that NSC contents of P. australis are almost always higher than those of S. alterniflora at every growth stage, every tidal level and every part of plants. The NSC contents in both species increase with the decrease of tidal levels, especially for S. alterniflora, which might be helpful to improve their salt tolerance. NSC contents in both species increase from the early growth stage to rapid growth stage and to the end of growth stage. NSC contents in leaves are higher than those in stems and roots in both species. Total NSC contents in S. alterniflora are lower than those in P. australis, but the proportions of NSC contents in underground parts of P. australis are lower than those in S. alterniflora. NSC contents of S. alterniflora at the stem base are less than those of P. australis, implying that the growth of roots and rhizomes, resistance ability to disturbance and basal tillering ability for S. alterniflora may be stronger than those of P. australis. The proportions of NSC contents in underground parts of both species decrease with the increase of tidal levels, showing the change trend from NSC content dominance in underground parts to aboveground parts in two species.%在上海崇明东滩湿地,外来植物互花米草种群和本土植物芦苇种群在潮间带生境形成竞争态势.文中对2种植物体内各部分的非结构性贮藏碳水化合物(NSC)质量分数的时空变化特征进行了研究,结果表明:在各生长发育时期、各个潮位生境以及植株各部位,几乎总是芦苇体内的NSC质量分数多于互花米草,且随着潮间带高程的降低,芦苇和互花米草都表现出体内的NSC质量分数增加的趋势,尤其以互花米草更为明显,这可能有助于提高它们的耐盐能力.从生长初期到生长中期再到生长后期,芦苇与互花米草植株体内NSC总质量分数依次递增；芦苇与互花米草各部位中所含NSC质量分数由大到小的顺序为叶片、茎、根；互花米草体内的NSC总质量分数低于芦苇,但互花米草地下部分NSC质量分数所占比例大于芦苇,互花米草地上部分茎基部的NSC质量分数所占比例小于芦苇,表明互花米草的根和地下根茎的生长能力、耐干扰性及基部分蘖能力可能要强于芦苇.随着潮间带高程的升高,芦苇和互花米草地下部分NSC质量分数所占比例均有下降趋势,且植物体内NSC质量分数从地下部分占优势逐渐变为地上部分占优势.
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