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51.
Bacterial diversity and function in the Baltic Sea with an emphasis on cyanobacteria 总被引:1,自引:0,他引:1
Sivonen K Halinen K Sihvonen LM Koskenniemi K Sinkko H Rantasärkkä K Moisander PH Lyra C 《Ambio》2007,36(2-3):180-185
In this article we summarize the current knowledge of Baltic Sea cyanobacteria, focusing on diversity, toxicity, and nitrogen fixation in the filamentous heterocystous taxa. We also review the recent results of our microbial diversity studies in planktonic and benthic habitats in the Baltic Sea. Based on molecular analyses, we have improved the understanding of cyanobacterial population structure by assessing genetic diversity within species that are morphologically inseparable. Moreover, we have studied microbial functions such as toxin production and nitrogen fixation in situ under different environmental conditions. Phosphorus limitation of bloom-forming, nitrogen-fixing cyanobacteria was clearly verified, emphasizing the importance of continuous efforts to reduce this element in the Baltic Sea. We have designed a rapid and reliable detection method for the toxic cyanobacterium Nodularia spumigena, which can be used to study bloom formation of this important toxin producer. 相似文献
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John G. Ewen Leila Walker Stefano Canessa Jim J. Groombridge 《Conservation biology》2015,29(2):341-349
Supplementary feeding is often a knee‐jerk reaction to population declines, and its application is not critically evaluated, leading to polarized views among managers on its usefulness. Here, we advocate a more strategic approach to supplementary feeding so that the choice to use it is clearly justified over, or in combination with, other management actions and the predicted consequences are then critically assessed following implementation. We propose combining methods from a set of specialist disciplines that will allow critical evaluation of the need, benefit, and risks of food supplementation. Through the use of nutritional ecology, population ecology, and structured decision making, conservation managers can make better choices about what and how to feed by estimating consequences on population recovery across a range of possible actions. This structured approach also informs targeted monitoring and more clearly allows supplementary feeding to be integrated in recovery plans and reduces the risk of inefficient decisions. In New Zealand, managers of the endangered Hihi (Notiomystis cincta) often rely on supplementary feeding to support reintroduced populations. On Kapiti island the reintroduced Hihi population has responded well to food supplementation, but the logistics of providing an increasing demand recently outstretched management capacity. To decide whether and how the feeding regime should be revised, managers used a structured decision making approach informed by population responses to alternative feeding regimes. The decision was made to reduce the spatial distribution of feeders and invest saved time in increasing volume of food delivered into a smaller core area. The approach used allowed a transparent and defendable management decision in regard to supplementary feeding, reflecting the multiple objectives of managers and their priorities. 相似文献
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López Gabriela Riviello Martinez Leila Marina Freyre Laura Freire María Cecilia Vladimirsky Sara Rabossi Alejandro Cisterna Daniel Marcelo 《Food and environmental virology》2021,13(1):64-73
Food and Environmental Virology - Cosaviruses (CoSV) and Saffold cardiovirus (SAFV) are novel members of the Picornaviridae family. The Matanza-Riachuelo river basin covers a total area of 2200 km2... 相似文献
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Leila Asadollahi Hossein Salehizadeh Ning Yan 《Journal of Polymers and the Environment》2016,24(2):119-128
In this research, a biosurfactant-producing bacterium with capability of asphaltene degradation was isolated from oil-contaminated soil samples, and identified as Bacillus cereus. This strain produced an effective biosurfactant in the presence of molasses and the surface tension was reduced to the level of 36.4 mN/m after 48 h under optimum conditions. The optimum values of carbon-to-nitrogen ratio (C:N), pH, and temperature for biosurfactant production were determined as 30:1, 7.3 and 29 °C, respectively, using response surface methodology. The maximum emulsification activity in the culture broth was 53 % after 48 h using kerosene at 25 °C. The goodness of fit of four growth kinetic models including Tessier, Contois, Logistic and Westerhoff was compared for the bacterial growth and molasses utilization of B. cereus in 5-L batch bioreactor during 120 h. Conducted kinetic study showed that biosurfactant production had a good fit with the Contois growth kinetic model (R2 = 0.962) and the maximum specific growth rate (µ max ), saturation constant (K s ) and the yield of biomass per substrate (Y x/s ) were determined to be 0.145 h?1, 1.83 g/L and 0.428 g/g, respectively. The asphaltene biodegradation in flask was evaluated by FTIR analysis and quantified by a spectrophotometer. This bacterium was able to degrade up to 40 % of asphaltene as a sole carbon and energy source after 60 days at 28 °C. The resulting surface tension of 30.2 mN/m with the critical micelle concentration of 23.4 mg/L indicated good efficiency of the biosurfactant. 相似文献
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Neckel Alcindo Korcelski Cleiton Silva Luis F. O. Kujawa Henrique Aniceto Bodah Brian William Figueiredo Adriano Marcos Rodrigues Maculan Larcio Stolfo Gonalves Affonso Celso Bodah Eliane Thaines Moro Leila Dal 《Environment, Development and Sustainability》2022,24(9):10728-10751
Environment, Development and Sustainability - The increasing mortality of COVID-19 can aggravate soil contamination by metals, harmful to the health of the population, requiring new projects for... 相似文献
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Journal of Polymers and the Environment - In this study, we produced a novel chemical cross-linked Guar gum/Poly(methylvinylether-alt-maleicacid) (GG/PMVE-MA) hydrogels with various blending weight... 相似文献
59.
Shabahang Zahra Nouri Leila Nafchi Abdorreza Mohammadi 《Journal of Polymers and the Environment》2022,30(9):3985-3998
Journal of Polymers and the Environment - The aim of this work was to preparation of edible films based on whey protein isolate/pectin (WPIP) that containing betanin pigments (BP) and copper (I)... 相似文献
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Mohebian Zahra Tajmohammadi Issa Yavari Maroufi Leila Ramezani Soghra Ghorbani Marjan 《Journal of Polymers and the Environment》2022,30(3):867-877
Journal of Polymers and the Environment - Newly, the usage of nanofibers (NFs) as wound dressings with the aim of their rapid healing and prevention of bacterial infection has been considered by... 相似文献