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                      |  SCI论文目录 |  
                    
                     
                      |  围栏封育对轻牧与重牧金露梅灌丛的影响 |   
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                      | 出 版 社:草地学报  第12卷 第2期 |   
                      | 发表时间:2004年 6月 |   
                      | 台  站:
                        海北高寒草甸生态系统定位研究站 |   
                      | 作  者:周华坤, 周 立, 赵新全, 周彦艳, 刘 伟, 严作良 |   
                      | 点 击 率:5999 |   
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                      | 关 键 字:关键词:草原学;生态;封育;轻牧;重牧;金露梅灌丛 |   
                      | 摘  要:摘要:连续5年的封育对轻牧与重牧区金露梅灌丛产生了影响。结果表明:封育后轻牧与重牧区的丰富度指数、多样性指数和均匀度指数都有所下降;总盖度、枯草盖度和上下层株高增加,绿草盖度减少,群落内主要植物种群特征发生相应变化,轻牧区金露梅灌丛的莎草类、杂草类和金露梅的地上生物量减少,而枯草、禾草的生物量增加,其中枯草生物量增加显著(P<0.05),优良牧草比例由0.72下降为0.62;在重牧区金露梅灌丛的枯草、禾草及莎草生物量增加显著(P<0.05),金露梅的生物量增加不显著(P>0.05),而杂草生物量减少显著(P<0.05),优良牧草比例由0.48上升为0.59;围栏封育后轻牧区金露梅灌丛的草场质量指数明显下降,重牧区草场质量指数明显上升。 |   
                      | 关 键 字(英文):Keywords:Grasslandscience;Ecology;Fencing;Lightlygrazing;Heavilygrazing;Potentillafruticosashrub |   
                      | 摘  要(英文):Abstract:Afive-successive-yearfencingofthelightlyandheavilygrazingPotentillafruticosashrublandshasdecreasedtheirspeciesrichness,plantdiversityandevenness.Thetotalcoverage,deadmaterialscoverage,andheightoftopandbottomlayersoftheplantcommunitieshaveallincreased,whiletheliveshootcoveragehasdecreased.Fencinghasalsoaffectedthecharacteristicsofthetwoplots'plantpupulations.Inthelightlygraz-ingplot,theabove-groundbiomassofsedges,forbs,andP.fruticosahavedwindled,whereasthebiomassofdeadmaterialsandgrasseshaveexpanded,withthebiomassofdeadmaterialsincreasingmarkedly(P<0.05).Theproportionofpalatableherbagesdroppedfrom0.72to0.62.Intheheavilygrazingplot,thebiomassofdeadmaterials,grassesandsedgeshaveincreasednoticeably(P<0.05),thebiomassofP.fruticosadidnotex-pandedmuch(P>0.05),whilethatofforbsdwindledmarkedly(P<0.05).Theproportionofpalatableherbagesrosefrom0.48to0.59.Consequently,fencingimpairsthequalityoflightlygrazingP.fruticosashrub-land,andimprovesthequalityofheavilygrazingP.fruticosashrubland. |   
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