Quantitative Classification and Ordination of the Subalpine Meadows in Luyashan Mountain

The subalpine meadows in Luyashan Mountain are one of the typical meadows in north China and play an important role in water and soil conservation,eco-tourism resource exploitation and bio-diversity protection and so on.The meadows in west Luyashan Mountain were classified and ranked by TWINSPAN and DCA into 13 associations that were located at different altitudes above sea level.The results of the classification and ordination better reflected the relationship of plant associations with environmental gradients that was verified in the twodimension ordination diagram by DCA.The axes of the ordination by DCA displayed the gradient changes of the altitude above sea level,soil moisture and slope aspects as well as that the altitude above sea level,water and thermal conditions and landforms are the major ecological factors to exert influence on plant associations.