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991.
In agricultural landscapes, studies that identify factors driving species richness and occupancy are important because they can guide farmers to use conservation practices that minimize species loss. In this context, anurans are threatened by habitat loss because they depend on the characteristics of both local water bodies and adjacent landscapes. We used a model selection approach to evaluate the influence of local and landscape variables in determining anuran species richness and occurrence in 40 freshwater bodies in a heavily deforested region of semideciduous Atlantic Forest in southeastern Brazil. Our aim was to develop recommendations for conservation of anuran communities in rural areas. Pond hydroperiod and area were the most important variables for explaining anuran species richness and occupancy, with greatest species richness being found in water bodies with intermediate hydroperiod and area. Other important variables that reflected individual species occupancies were the number of vegetation types and pond isolation. In addition, recent studies evidenced that water bodies near forest fragments have higher anuran abundance or diversity. In conclusion, we suggest the maintenance of semi-permanent ponds, isolated from large rivers or reservoirs and near forest fragments, as an effective strategy to conserve anuran fauna in agricultural landscapes of southeastern Brazil. Brazilian government requires the maintenance of forests as legal reserve in each farm, and farmers need to maintain ponds as drinking water for cattle or crop irrigation. For this reason, the guidelines suggested in the present study can be easily adopted, without additional costs to rural productivity. 相似文献
992.
María M. Martorell Hipólito F. Pajot Pablo M. Ahme Lucía I.C. de Figueroa 《环境科学学报(英文版)》2017,29(3):78-87
Azo dyes are extensively used in textile dyeing and other industries. Effluents of dying industries are specially colored and could cause severe damage to the environment. The anaerobic treatment of textile dying effluents is nowadays the preferred option, but it could generate carcinogenic aromatic amines. Recently, yeasts have become a promising alternative, combining unicellular growth with oxidative mechanisms. This work reports the characterization of the first methylotrophic yeast with dye decolorizing ability, Candida boidinii MM 4035 and some insights into its decoloration mechanism. The analysis of two selected media revealed a possible two stages mechanism of Reactive Black 5 decoloration. In glucose poor media, decoloration is incomplete and only the first stage proceeds, leading to the accumulation of a purple compound. In media with higher glucose concentrations, the yeast is able to decolorize totally an initial concentration of 200 mg/L. The entire process is co-metabolic, being largely dependent on glucose concentration but being able to proceed with several nitrogen sources. Manganese dependent peroxidase but not laccase activity could be detected during decoloration. Aromatic amines do not accumulate in culture media, supporting an oxidative decoloration mechanism of unknown ecophysiological relevance. 相似文献
993.
Johannes G. Leskens Christian Kehl Tim Tutenel Timothy Kol Gerwin de Haan Guus Stelling Elmar Eisemann 《Mitigation and Adaptation Strategies for Global Change》2017,22(2):307-324
Developing strategies to mitigate or to adapt to the threats of floods is an important topic in the context of climate changes. Many of the world’s cities are endangered due to rising ocean levels and changing precipitation patterns. It is therefore crucial to develop analytical tools that allow us to evaluate the threats of floods and to investigate the influence of mitigation and adaptation measures, such as stronger dikes, adaptive spatial planning, and flood disaster plans. Up until the present, analytical tools have only been accessible to domain experts, as the involved simulation processes are complex and rely on computational and data-intensive models. Outputs of these analytical tools are presented to practitioners (i.e., policy analysts and political decision-makers) on maps or in graphical user interfaces. In practice, this output is only used in limited measure because practitioners often have different information requirements or do not trust the direct outcome. Nonetheless, literature indicates that a closer collaboration between domain experts and practitioners can ensure that the information requirements of practitioners are better aligned with the opportunities and limitations of analytical tools. The objective of our work is to present a step forward in the effort to make analytical tools in flood management accessible for practitioners to support this collaboration between domain experts and practitioners. Our system allows the user to interactively control the simulation process (addition of water sources or influence of rainfall), while a realistic visualization allows the user to mentally map the results onto the real world. We have developed several novel algorithms to present and interact with flood data. We explain the technologies, discuss their necessity alongside test cases, and introduce a user study to analyze the reactions of practitioners to our system. We conclude that, despite the complexity of flood simulation models and the size of the involved data sets, our system is accessible for practitioners of flood management so that they can carry out flood simulations together with domain experts in interactive work sessions. Therefore, this work has the potential to significantly change the decision-making process and may become an important asset in choosing sustainable flood mitigations and adaptation strategies. 相似文献
994.
Aim
Injuries in adolescence are an important public health problem and a major cause of morbidity and mortality in this age group. This study aimed to determine the behaviour profile associated to risk of injury and the differences between genders, region and ethnic origin.Methods
A cross-sectional study design of a nationally representative sample of 1581 adolescents of the Portuguese Health Behaviour in School-Aged Children study.Results
An occurrence of one injury-related event in the previous year was reported by 21.4% of the respondents and 5.9% referred having more than one injury-related event. Boys reported higher frequency of those events when compared to girls, and non-Portuguese subjects referred higher frequency of events. Scoring higher in violence-related behaviour and psychosomatic complaints was associated to higher chances of referring more than one injury-related event.Conclusion
Gender, social background and behaviour profile are factors that seem to influence the risk of injuries. This information should guide those involved in the planning of injuries prevention programs in youth. 相似文献995.
Introduction
This study describes a method for reducing the number of variables frequently considered in modeling the severity of traffic accidents. The method's efficiency is assessed by constructing Bayesian networks (BN).Method
It is based on a two stage selection process. Several variable selection algorithms, commonly used in data mining, are applied in order to select subsets of variables. BNs are built using the selected subsets and their performance is compared with the original BN (with all the variables) using five indicators. The BNs that improve the indicators’ values are further analyzed for identifying the most significant variables (accident type, age, atmospheric factors, gender, lighting, number of injured, and occupant involved). A new BN is built using these variables, where the results of the indicators indicate, in most of the cases, a statistically significant improvement with respect to the original BN.Conclusions
It is possible to reduce the number of variables used to model traffic accidents injury severity through BNs without reducing the performance of the model.Impact on Industry
The study provides the safety analysts a methodology that could be used to minimize the number of variables used in order to determine efficiently the injury severity of traffic accidents without reducing the performance of the model. 相似文献996.
Cabruca is an agroforest of cacao trees shaded by native forest trees. It is the predominant vegetation type throughout eastern part
of the range of the golden-headed lion tamarins, Leontopithecus chrysomelas, an endangered primate endemic to Atlantic Forest. Understanding how lion tamarins use this agroforest is a conservation
priority. To address this question, we documented the diet, home range size, group sizes and composition, density, number
of litters and body condition of lion tamarins living in cabruca, and other habitats. Jackfruit, Artocarpus heterophyllus, was the most used species used by lion tamarins in cabruca and was widely available and used throughout the year. In cabruca, home range size was the smallest (22–28 ha) and density of lion tamarins was the highest (1.7 ind/ha) reported for the species.
Group size averaged 7.4 individuals and was not significantly different among the vegetation types. In cabruca, groups produced one or two litters a year, and all litters were twins. Adult males in cabruca were significantly heavier than males in primary forest. Our study is the first to demonstrate that breeding groups of golden-headed
lion tamarins can survive and reproduce entirely within cabruca agroforest. Jackfruit proved to be a keystone resource for lion tamarins in cabruca, and bromeliads were important as an animal prey foraging microhabitat. In cases where cabruca contains concentrated resources, such as jackfruit and bromeliads, lion tamarins may not only survive and reproduce but may
fare better than in other forest types, at least for body condition and reproduction. 相似文献
997.
Matías Feijoo Enrique P. Lessa Rocío Loizaga de Castro Enrique A. Crespo 《Marine Biology》2011,158(8):1857-1867
Several major breeding areas have been defined for the South American sea lion (Otaria flavescens) along the Atlantic Ocean including the Uruguayan and Patagonian coasts. Together with a documented and severe reduction
in population sizes caused by commercial hunting in the last century, these areas show opposite population trends. While Patagonian
populations are recovering since hunting ceased, Uruguayan populations are declining. In this context, population genetic
structure and genetic diversity were studied for the first time with both nuclear (microsatellites) and mitochondrial (control
region) markers together. Alternative scenarios were found for both markers. While mitochondrial marker showed geographically
structured populations, the nuclear loci showed a lack of geographical structure. These opposite patterns in genetic structure
could be explained by female phylopatry and high male dispersion. The reduction in population size caused by commercial hunting
did not leave a detectable footprint of bottleneck at the genetic level. 相似文献
998.
Dadvand P Basagaña X Figueras F Amoly E Tobias A de Nazelle A Querol X Sunyer J Nieuwenhuijsen MJ 《Journal of environmental monitoring : JEM》2011,13(11):3222-3228
Desert dust is one of the natural contributors to atmospheric particulate matter worldwide. Although particulate pollution has been shown to adversely affect pregnancy, the available evidence on the impact of dust episodes on pregnancy is very scarce. The aim of this study was to evaluate the impact of Saharan dust episodes on pregnancy complications (preeclampsia and bacteriuria) and outcomes (birth weight and gestational age at delivery). This study was based on a cohort of births (N = 3565) that occurred in a major university hospital in Barcelona during 2003-2005. To determine Saharan dust episodes, we developed a two-stage approach based on meteorological evidence of the presence of Saharan dust cloud over the region and unusually high levels of particulate levels on the ground while taking account of traffic sources. The associations between the number of Saharan dust episodes during whole pregnancy as well as each pregnancy trimester and pregnancy complications and outcomes were analysed. There were 152 days (out of 838 days) with Saharan dust cloud over the region from which 45 days were determined as episodic days. We did not observe any statistically significant harmful effect of Saharan dust episodes on our included pregnancy complications and outcomes. However, we observed a small but statistically significant increase in gestational age at delivery in association with the number of episodic days during the third trimester and whole pregnancy (0.8 and 0.5 days respectively). Our findings were not suggestive for any adverse effect of Saharan dust episodes on our included pregnancy complications and outcomes. 相似文献
999.
Pourcelot L Boulet B Le Corre C de Vismes Ott A Cagnat X Loyen J Fayolle C Van Hecke W Martinez B Petit J Kaltenmeier R Gieré R 《Journal of environmental monitoring : JEM》2011,13(5):1327-1336
Cypress needles collected at the edge of the Malvési uranium facility (SW France) exhibit enhanced activities of actinides and some decay products (uranium, americium, plutonium, (230)Th, (226)Ra) compared to a remote site. These enhanced activities resulted from the release of U via smokestacks and passive release from former artificial ponds located inside the nuclear site. Enhanced activities are also observed in selected produce (wheat, lettuce, fruits) sampled from the edge of the site. However, excess actinides measured in wheat grains in 2007 are inconsistent with the activities and the uranium ratio measured in the soils. This result suggests that the studied annual crops were contaminated mainly through the short-term release of airborne actinides, and that other transfer pathways, such as, uptake through the roots or adhesion of soil particles, were negligible. 相似文献
1000.
Bravo AG Bouchet S Amouroux D Poté J Dominik J 《Journal of environmental monitoring : JEM》2011,13(4):974-982
In Lake Geneva, Switzerland, the most Hg-contaminated sediments have been found in the Vidy Bay where high Hg contents largely exceeds the background levels of Lake Geneva sediments. This contamination has been attributed to the discharge of a waste water treatment plant (WWTP). Total Hg (THg) and monomethylmercury (MMHg) were determined in bulk sediment and in three different grain size fractions (i: clay and silt, ii: fine-coarse sand, iii: and very coarse sand and gravel) collected close to the outlet pipe of a WWTP in order to verify whether the standardized procedures of sediment treatment is adequate for this setting and, by extension, for similar contaminated sites. THg was homogeneously distributed in the different grain size fractions and was correlated to organic matter content (R(2) = 0.6). MMHg was homogeneously distributed in the two finer grain fractions (Φ < 0.063 mm; 0.063 mm < Φ <1 mm). The results of this study suggested that the analysis of the bulk sediment seems to be more appropriate for the assessment of the content and spatial distribution of Hg in freshwater sediments contaminated by WWTPs. 相似文献