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血气仪器的新的里程碑
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作者 王佳棣 《中国医疗器械杂志》 CAS 2002年第5期351-351,共1页
由美国Nova Biomedical公司推出的StatProfile(R)PHOx血气/血氧仪标志了当今血气仪器制造技术发展中的一个新的里程碑。它采用的高新技术比血气仪历史上的任何其它分析仪都更多、更新,其主要特性有以下几点:
关键词 STAT profile(r)PHOx 血气分析 质量控制 血气仪器
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Old coppice versus high forest:the impact of beech forest management on plant species diversity in central Apennines(italy) 被引量:2
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作者 Andrea Scolastri Laura Cancellieri +1 位作者 Marco Iocchi Maurizio Cutini 《Journal of Plant Ecology》 SCIE CSCD 2017年第2期271-280,共10页
Aims Silvicultural management plays a major role in shaping understory diversity through its action on stand structure.in many parts of Europe,recent socioeconomic changes have led to the progressive abandonment of co... Aims Silvicultural management plays a major role in shaping understory diversity through its action on stand structure.in many parts of Europe,recent socioeconomic changes have led to the progressive abandonment of coppicing in favor of high forest(HF)management.in order to examine how this change impacts understory species,we compared old coppice-with-standards and HF stands in terms of structural features and understory richness and composition,also taking into account the diagnostic species pool of the habitat.Since the management systems for coppices and HFs differ in cutting regime,we expect that they would cause different changes in floristic composition and richness.Methods The study area was the Montagne della Duchessa massif,in central italy.Structural differences and floristic richness were compared,and the diagnostic species diversity was analyzed using rarefaction curves and Rényi diversity profiles.Differences in understory com-position were analyzed through indicator species analysis.Important Findings Our results showed that,though the old coppices have a slightly higher number of understory species in general,the HF stands have greater mean species richness in both understory and diagnostic species,the latter being more evenly distributed inside the com-munity.These finding were related to the cut regime,which favor a constant canopy cover over time and thus the maintenance of more stable microclimatic conditions,promoting the higher abundance and evenness of shade-tolerant and vernal species.Conversely,the dense canopy of the old coppice appears to affect the understory richness by reducing the presence of light-demanding species,but still without a complete recolonization of the shade-tolerant spe-cies.Overall,our findings provide the first insights supporting that,in a Mediterranean montane context,old coppice conversion to HF could over time improve the species diversity in these habitats and help maintain good conservation status of the typical mature beech forests. 展开更多
关键词 diagnostic species habitat directive 92/43 EEC Mediterranean beech forests rarefaction curves rényi diversity profiles SILVICULTUrE understory diversity understory richness
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