补播对高寒草甸生产力和植物多样性的影响

摘要

为了解补播对高寒草甸退化草地恢复过程中群落生产力、功能群结构和物种多样性方面的影响,于2010年5月以位于青藏高原东段的玛曲高寒草甸为研究对象,进行了补播试验.结果表明,补播显著提高地上生物量,同时物种数和丰富度指数Margalef也有显著增加,其中补播处理地上生物量是不补播处理的1.31～1.44倍.补播后莎草类和禾草类地上生物量都呈增长趋势,补播后禾草类地上生物量显著提高,其中最高是不补播的2.7倍,杂类草在群落中所占比例显著降低.适量补播既可以使草地的经济价值得以提高,同时也有利于高寒退化草地的恢复和生态系统的稳定.%The effects of reseeding on community productivity,the structure of functional groups and on plant diversity have been carried out since May 2010 in a reseeding experiment on Maqu degraded alpine meadow in the east of the Tibetan Plateau.After reseeding,the productivity,species richness and the richness index of Margalef significantly increased.Comparing the treatment without reseeding to that with reseeding,the productivity increased 31%-44%.The productivity of gramineae and sedge increased along with an increased quantity of reseeding,especially with sedges in which productivity was 2.7 times that in the treatment without reseeding.The proportion of forbs in the community was greatly reduced in response to the reseeding.In conclusion,proper reseeding could raise the utility value of alpine meadows but in the meantime it is better to recover degraded grassland and maintain the stability of the ecosystem.