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山地荒漠草原不同植物群落物种-多度关系分析 被引量:2
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作者 尚占环 姚爱兴 龙瑞军 《河北大学学报(自然科学版)》 CAS 北大核心 2005年第2期173-178,共6页
在群落样方调查的基础上,计算群落物种重要值,确定群落类型.对群落物种重要值采用分割线段模型(brokenstickmodel)、对数级数分布(Logseriesdistribution)、对数正态分布(Lognormaldistribution)、几何级数分布(Geometricseriesdistribu... 在群落样方调查的基础上,计算群落物种重要值,确定群落类型.对群落物种重要值采用分割线段模型(brokenstickmodel)、对数级数分布(Logseriesdistribution)、对数正态分布(Lognormaldistribution)、几何级数分布(Geometricseriesdistribution)等4个种-多度模型进行拟合.结果表明石质山坡(长芒草Sti pabungeana-冷蒿Artemisiafrigida)群落对数级数拟合结果更好,土质山坡群落(短花针茅Stipabrevifo ra-长芒草Stipabungeana)对数正态分布拟合更好,说明了2个群落结构是对2个样地环境特点与放牧干扰相互作用的响应.沙化草地(油蒿Artemisiaordosica-刺叶柄棘豆Oxytropisaciphlla)群落中油蒿处于极优势地位,占据整个群落的大多数生态空间.拟合检验表明该山地草地植被物种分布格局较符合随机生态位假说和生态位占领假说,严重的放牧干扰不仅降低了优势物种在群落中的优势程度,使次优势物种及其他物种也没能较好的发育,说明外部非生物环境对群落胁迫程度较大. 展开更多
关键词 干旱山地 荒漠草原 多样性 种-多度模型
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陕西洛河流域不同生境蝗虫的群落结构 被引量:9
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作者 刘慧 廉振民 +1 位作者 常罡 孔光耀 《昆虫知识》 CSCD 北大核心 2007年第2期214-218,共5页
应用种-多度分布模型、多样性指数、相似性分析、主成分(PCA)分析及多元逐步回归等方法比较了洛河流域不同生境的蝗虫群落结构。结果显示:洛河流域各生境的蝗虫分布基本上服从Preston对数正态分布,其中以森林拟合的最好。各多样性指数... 应用种-多度分布模型、多样性指数、相似性分析、主成分(PCA)分析及多元逐步回归等方法比较了洛河流域不同生境的蝗虫群落结构。结果显示:洛河流域各生境的蝗虫分布基本上服从Preston对数正态分布,其中以森林拟合的最好。各多样性指数的变化趋势均为森林>森林草原>河滩和农田>典型草原。在相似性分析中,典型草原、森林草原和森林这3种生境相似性很高,而河滩和农田则是完全不同的另一种生境。对各生境植被因素和蝗虫群落所进行的主成分分析,结果非常理想,两维主成分的累计方差贡献率分别达到了92.558%和78.566%。通过多元逐步回归发现,影响蝗虫种类和数量变化的植被因有草本植物高度多样性、树木盖度、豆科优势度、禾本科优势度和其他科优势度等。 展开更多
关键词 种-多度模型 相似性 主成分 多元逐步回归
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Species Abundance Distribution Patterns of a Toona ciliata Community in Xingdoushan Nature Reserve 被引量:4
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作者 WANG Yang ZHU Shengjie +3 位作者 LI Jie HE Xiuling JIANG Xiongbo ZHANG Min 《Journal of Resources and Ecology》 CSCD 2019年第5期494-503,共10页
With the goal of model fitting species abundance distribution patterns of the tree,shrub and herb layers of the natural Toona ciliata community in Xingdoushan Nature Reserve,Enshi Autonomous Prefecture,Hubei Province,... With the goal of model fitting species abundance distribution patterns of the tree,shrub and herb layers of the natural Toona ciliata community in Xingdoushan Nature Reserve,Enshi Autonomous Prefecture,Hubei Province,we used the data collected from the field survey and employed different ecological niche models.The models tested were the broken stick model(BSM),the overlapping niche model(ONM)and the niche preemption model(NPM),as well as three statistic models,the log-series distribution model(LSD),the log-normal distribution model(LND)and the Weibull distribution model(WDM).To determine the fitted model most suitable to each layer,the fitting effects were judged by criteria of the lowest value of Akaike Information Criterion(AIC),Chi-square and the K-S values with no significant difference(P>0.05)between the theoretical predictions and observed species abundance distribution values.The result showed:(1)The fitting suitability and goodness of fit of the tree,shrub and herb layers by using the three ecological niche models were ranked as:NPM>BSM>ONM.Of the three statistical models,by accepting the fitting results of the three layers,WDM was the best fitting model,followed by LND.By rejecting the fitting tests of the herb layer,LSD had the worst fitting effect.The goodness of the statistical models was ranked as:WDM>LND>LSD.In general,the statistical models had better fitting results than the ecological models.(2)T.ciliata was the dominant species of the tree layer.The species richness and diversity of the herb layer were much higher than those of either the tree layer or the shrub layer.The species richness and diversity of the shrub layer were slightly higher than those of the tree layer.The community evenness accorded to the following order:herb>shrub>tree.Considering the fitting results of the different layers,different ecological niche models or statistical models with optimal goodness of fit and ecological significance can be given priority to in studying the species abundance distribution patterns of T.ciliata communities. 展开更多
关键词 Toona ciliata community tree-shrub-herb layer niche model statistical model species abundance distribution pattern fitting model
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