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PFU微型生物群落水质鉴别及群落参数变化模式的研究 被引量:13
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作者 陈建 沈韫芬 《环境科学学报》 CAS CSCD 北大核心 2000年第2期156-161,共6页
基于PFU微型生物群落参数调查数据,对湖北省汉江两条污染带11个站点和湖南常德市水系15个站点所属水质组别进行了综合分析研究.所得典型鉴别函数能够对水质组别作出有效的鉴别,分类函数对站点的水质组别分类正确率达到96%;群落参数对化... 基于PFU微型生物群落参数调查数据,对湖北省汉江两条污染带11个站点和湖南常德市水系15个站点所属水质组别进行了综合分析研究.所得典型鉴别函数能够对水质组别作出有效的鉴别,分类函数对站点的水质组别分类正确率达到96%;群落参数对化学综合污染指数(P)的响应不呈简单的线性关系,群落参数的变化存在一定模式.提出了“转折区”(turninginterval)概念.水质由洁净到严重污染的变化过程中,在转折区内,微型生物群落的5个参数与P的相关性将发生根本性改变:D和Seq与P由正相关转变为负相关,T90%由负相关转变为正相关,HI和G相关性的显著程度发生改变.本研究显示,这个转折区存在于水质污染区段. 展开更多
关键词 微型生物群落 PFU 水质监测 群落参数变化 模式
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Community responses to extreme climatic conditions 被引量:2
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作者 Frederic JIGUET Lluis BROTONS Vincent DEVICTOR 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第3期406-413,共8页
Species assemblages and natural communities are increasingly impacted by changes in the frequency and severity of extreme climatic events. Here we propose a brief overview of expected and demonstrated direct and indir... Species assemblages and natural communities are increasingly impacted by changes in the frequency and severity of extreme climatic events. Here we propose a brief overview of expected and demonstrated direct and indirect impacts of extreme events on animal communities. We show that differential impacts on basic biological parameters of individual species can lead to strong changes in community composition and structure with the potential to considerably modify the functional traits of the community. Sudden disequilibria have even been shown to induce irreversible shifts in marine ecosystems, while cascade effects on various taxonomic groups have been highlighted in Mediterranean forests. Indirect effects of extreme climatic events are expected when event-induced habitat changes (e.g. soil stability, vegetation composition, water flows altered by droughts, floods or hurricanes) have differential consequences on species assembled within the communities. Moreover, in increasing the amplitude of trophic mismatches, extreme events are likely to turn many systems into ecological traps under climate change. Finally, we propose a focus on the potential impacts of an extreme heat wave on local assemblages as an empirical case study, analysing monitoring data on breeding birds collected in France. In this example, we show that despite specific populations were differently affected by local temperature anomalies, communities seem to be unaffected by a sudden heat wave. These results suggest that communities are tracking climate change at the highest possible rate [Current Zoology 57 (3): 406-413, 2011]. 展开更多
关键词 Bird community Climate change DROUGHT Heat wave HURRICANE
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