伊犁绢蒿种群扩增与土壤养分的关系

Relationships between Seriphidium transiliense Population Diffusion and Soil Nutrition

对退化伊犁绢蒿种群生长的植被种类组成,伊犁绢蒿幼苗的数量特征、群落着生的土壤养分条件进行分析,阐明退化伊犁绢蒿种群扩散特征及其土壤养分的关系。结果表明,伊犁绢蒿的重要值随着退化梯度的增强而减小,角果藜、叉毛蓬和扁蓄逐渐成为退化草地的优势植物。伊犁绢蒿母株存在"肥岛"效应,即其土壤有机质、碱解氮、有效磷含量高于一年生群落,伊犁绢蒿幼苗在其周围1m左右密集生长,其土壤养分含量普遍高于一年生植物群落,表现出与一年生植物群落竞争土壤养分,以提高幼苗的存活率,有利于伊犁绢蒿种群的扩增。

In order to ill ust ra te the rela tionships bet ween Seri phidium tran silien se population diffusion and soil nutrient, the vegetation species composition, quantity characteristics of S. tran silien se seedling and soil nutrient of cornrn uni ties insertion were analyzed in the degraded S. tran silien se population. The results showed that the important value of S. tran silien se decreased with degradation increases. In turn Ceratocarpus arenarius .Petrosi mon ia sibirica and Polygon um auicuiare had gradually become the dominant plants of degraded grassland. There were effects of ＂fertile island＂ in S. tran siiien se ,that is, the content of its soil organic rnat tervavaila hle nitrogen,alklaine-hydrolyzale nitrogen were higher than that of annual communities. Surrounding mother plant about 1 tn , seedlings densely grew, its soil nutrient content was generally higher than that of annual communities, which showed it competed soil nutrient with annual communities for improving the survival rate and S. tran si lien se population diffusion.