3种野生地被植物对践踏胁迫的生理生态响应特征

不同强度践踏胁迫下，对3种野生地被植物主要生理生态响应特征进行了研究，结果表明：重度践踏胁迫下匍枝委陵菜的盖度、生物量下降幅度最大，和对照相比分别下降46.58%和43.53%。重度践踏胁迫下车前的纤维素含量最高，比对照增加43.31%。中度践踏胁迫下紫花地丁丙二醛含量积累最少，比对照升高28.57%。紫花地丁叶绿素含量对践踏胁迫响应敏感，轻度践踏可使叶绿素含量提高45.21%（p< 0.05），重度践踏使匍枝委陵菜和紫花地丁的叶绿素含量分别下降了21.59%和29.37%。践踏胁迫使3种野生地被植物的群体净光合速率下降。综合分析结果为车前最耐践踏，紫花地丁次之，匍枝委陵菜最不耐践踏。

Physiological and Ecological Responses of 3 Wild Groundcover Plants to Traffic Stress

Physiological and ecological characteristics of 3 wild groundcover plants were studied under different traffic stress. The results indicated that the coverage and aboveground biomass of Potentilla flagellaris Willd ex Sehleeht decreased fastest under severe traffic stress, 46.58% and 43.53% lower than control respectively. Cellulose content of Plantago asiatica L. was the highest under severe traffic stress, 43.31% higher than control. MDA of Viola philippica Makin. was the least under medium traffic stress, 28.57% higher than control. Chlorophyll content of V. philippica Makin. was most sensitive to traffic stress, 45.21%(p<0.05) higher than control under light traffic stress and 29.37% lower than control under severe traffic stress. Net photosynthesis rate of three wild groundcover plants under severe traffic stress decreased significantly. Based on comprehensive analysis of physiological and ecological indices, it could be concluded that traffic tolerance among the three wild groundcover plants was in the descending order of P. asiatica L.>V. philippica Makin.>P. flagellaris Willd ex Sehleeht.