切根与肥力调控对退化羊草草甸草原植被改良效果研究

Study on the Effects of Root Cutting and Fertilizer Regulation on Vegetation Improvement in Degraded Leymus chinensis Meadow Steppe

采用不同改良技术(切根、切根+不同浓度化肥、切根+不同浓度有机肥)对内蒙古呼伦贝尔退化羊草草甸草原植物群落物种组成、数量特征和物种多样性进行研究,结果表明:切根+高浓度施肥处理可以显著提高羊草重要值,其中切根+高浓度施化肥处理羊草重要值最高。试验初期,切根+中高浓度施化肥处理和切根+低浓度施有机肥处理可显著提高群落高度,而试验第三年可以显著提高群落盖度和密度。试验第三年,切根+高浓度施化肥处理组群落生物量显著最高。切根和切根+施肥处理对物种多样性指数提高效果不显著。综上所述,羊草草甸草原割草场改良过程中,在切根的基础上同时施肥,能够有效提高群落建群种羊草的重要值,其中切根+高浓度施化肥处理有助于提高群落生产力。

This experiment mainly studied the effects of improved techniques(root cutting,root cutting+different concentrations of chemical fertilizer,root cutting+different concentrations of organic fertilizer)on species composition,quantitative characteristics and species diversity of plant communities in degraded Leymus chinensis meadow steppe in Hulunbuir,Inner Mongolia.The results showed that root cutting,and high concentration of fertilizer treatments could significantly increase the important value of Leymus chinensis,in which root cutting+high concentration of chemical fertilizer treatment had the highest value.In the early stage of the experiment,root cutting+medium/high concentration chemical fertilizer and root cutting+low concentration organic fertilizer could significantly improve the plant community height.Above treatments also significantly improve the plant community coverage and density in the third year of the experiment.The treatment of root cutting+high concentration chemical fertilizer had the highest plant community biomass in the third year of the experiment.Root cutting and root cutting+fertilization treatment had no significant effect on the improvement of species diversity index.In conclusion,during the improvement of Leymus chinensis meadow steppe,the combination of root cutting,and fertilization can effectively improve the important value of Leymus chinensis as constructive species,in which root cutting+high concentration of chemical fertilizer treatment was more helpful to improve the plant community productivity.