科尔沁沙地草甸草场退化的原因与植物多样性变化  

Degradation and diversity changes of meadow grassland in Keerqin Sandy Land

作　　者：曹成有[1] 蒋德明[2] 朱丽辉[3] 南寅镐[2] 

机构地区：[1]东北大学理学院,辽宁沈阳110004 [2]中国科学院沈阳应用生态研究所,辽宁沈阳110016 [3]辽宁林业职业技术学院,辽宁沈阳110101

出　　处：《草业学报》2006年第3期18-26,共9页Acta Prataculturae Sinica

基　　金：国家"十五"科技攻关项目"科尔沁沙地植被重建与调控技术研究与示范"(2005BA517A08);辽宁省科学技术基金(20031013)资助

摘　　要：对科尔沁沙地典型草甸植被主要群落的优势种群在22年间的消长和物种多样性的变化进行了研究,分析了造成草场退化的主要原因。结果表明,科尔沁沙地草甸植被已出现了严重退化现象,物种多样性和均匀度下降,生态优势度上升。牧草产量和质量显著下降,优良牧草数量减少,适口性较差和有毒有害植物增加。造成草甸草场退化的主要原因有气候的暖干化、生境干旱化、土壤盐渍化和过度放牧,其中过度放牧是造成草甸植被退化的直接原因。分析了过度放牧对群落组成、生物量、物种多样性以及对建群种根茎中营养物质含量的影响等。The dynamic characteristics of species composition and species diversity of meadow grassland in Keerqin Sandy Land in the last 20 years were studied. The results showed that the meadow vegetation in Keerqin Sandy Land has seriously degraded. Species diversity and evenness of community has decreased and ecological dominance increased. The quality and production of herbaceous plants in general has declined.The quantity and dominance of fine herbaceous species decreased while that of poor quality and of poisonous grass species increased. The reasons for this grassland degradation included.warming and drying of the local climate, habitat drying, soil salinization and over grazing. Over grazing was the main and direct reason for degradation of the meadow vegetation. The influence of over grazing on species composition, biomass, diversity and nutrient content in of the main communities were also analyzed.

关 键 词：草甸植被 退化 退化原因 植物多样性 科尔沁沙地 

分 类 号：S812[农业科学—草业科学]