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Nadson R. Simões Maria Alice Mendes Colares Fábio A. Lansac‐Tôha Claudia C. Bonecker 《Austral ecology》2013,38(8):952-958
This study examined two models that are most frequently used to describe the relationship between species richness and productivity (SPR): monotonic positive and hump‐shaped models. We assessed zooplankton community diversity in response to algal productivity. The relationship between net primary productivity (NPP) and rarefied species richness was examined by fitting the data to two models and comparing them using the Akaike information criterion (AICc). Macrophyte banks with the highest net primary productivity had the highest zooplankton abundance. Our results pointed to a hump‐shaped model as the best fit to describe the relationship between zooplankton species richness and primary productivity (ΔAICc > 4). Thus, the diversity was lower at the extremes of productivity and higher at intermediate levels of productivity. We suggest that this relationship might occur because when the resource supply rates are low, environmental conditions are stressful, whereas a high availability of resources enhances competitive exclusion. Two observations supported this statement: (i) the total abundance of the community positively correlated with NPP (P < 0.05), indicating that less productive sites had few consumers and the raised productivity tended to favour the total abundance; (ii) NPP was negatively correlated with evenness (P < 0.05), indicating that productivity increased the dominance of certain species in the communities. Therefore, we challenged two of the models most frequently used to explain SPR, and discuss some mechanisms underlying a hump‐shaped SPR. 相似文献
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Multi-locus variable-number tandem repeat analysis differentiated 297 Salmonella enterica serovar Typhi blood culture isolates from Makassar in 76 genotypes and a single unique S. Typhi genotype was isolated from the cholecystectomy specimens of four patients with cholelithiasis. The high diversity in S. Typhi genotypes circulating in Makassar indicates that the number of carriers could be very large, which may complicate disease prevention and control. 相似文献
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de Souza Dilailson Arajo Kraus Cleber Nunes Burliga Ana Luiza de Melo Srgio Couceiro Sheyla Dias-Silva Karina Simes Nadson Ressye Braga Tony Bonnet Marie Paule da Motta Marques David 《Limnology》2022,23(2):275-286
Limnology - The Amazon floodplains are complex systems influenced by the annual hydrological regime with an effect on the structuring of physical, chemical and biological processes. Thus, we... 相似文献
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Sans résumé
Avec planches I et II 相似文献
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Simões Nadson R. Braghin Louizi S. M. Duré Gustavo A. V. Santos Josiane S. Sonoda Sérgio L. Bonecker Cláudia C. 《Hydrobiologia》2020,847(18):3845-3856
Hydrobiologia - Disturbances caused by both natural and anthropogenic forces can drive changes in alpha and beta taxonomic diversity and be accompanied by losses or gains in freshwater ecosystem... 相似文献