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11.
B. S. Sant’Anna D. M. Santos M. R. R. Marchi F. J. Zara A. Turra 《Environmental science and pollution research international》2014,21(10):6516-6524
Butyltin (BT) contamination was evaluated in hermit crabs from 25 estuaries and in sediments from 13 of these estuaries along about 2,000 km of the Brazilian coast. BT contamination in hermit crabs ranged from 2.22 to 1,746 ng Sn g-1 of DBT and 1.32 to 318 ng Sn g-1 of TBT. In sediment samples, the concentration also varied widely, from 25 to 1,304 ng Sn g-1 of MBT, from 7 to 158 ng Sn g-1 of DBT, and from 8 to 565 ng Sn g-1 of TBT. BTs are still being found in surface sediments and biota of the estuaries after the international and Brazilian bans, showing heterogeneous distribution among and within estuaries. Although hermit crabs were previously tested as an indicator of recent BT contamination, the results indicate the presence of contamination, probably from resuspension of BTs from deeper water of the estuary. Figure
Contamination of the environment and biota continues after the ban 相似文献
12.
Karim D. Kalache Bianca Masturzo Agostino Pierro Donald Peebles Lyn S. Chitty 《黑龙江环境通报》2001,21(4):308-310
Sonographic demonstration of normal tracheal diameter and breathing-related lung fluid flow at 30 weeks' gestation in a fetus with a giant neck mass confirmed patent airways, thus avoiding an EXIT procedure. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
13.
Bianca Unglaub Jasmin Ruch Marie E. Herberstein Jutta M. Schneider 《Behavioral ecology and sociobiology》2013,67(5):785-794
A reduced predation risk is considered to be a major adaptive advantage of sociality. While most studies are concerned with non-predatory prey species, group-living predators are likely to face similar threats from higher-order predators. We studied the relationship between group size and predation risk in the subsocial crab spider Diaea ergandros by testing predictions from theoretical models including attack abatement as well as the formation of protective retreats. In a field survey, we found predatory clubionid spiders in 35 % of the D. ergandros nests and as predicted, nest size did not correlate with predator presence. In a subsequent laboratory experiment, we observed survival probability, nest construction activity and feeding behaviour including weight development between groups of different sizes as well as in the absence or presence of a predator. Large groups had an advantage in terms of survival and growth compared to smaller groups or single individuals. They also built significantly larger nests than smaller groups, supporting the idea of protective retreat formation being an adaptive benefit to group living. Even though clubionids did attack D. ergandros, they did not significantly affect overall mortality of D. ergandros. The feeding experiment showed that spiders fed on a larger proportion of flies in the presence of a predator. However, these groups gained significantly less weight compared to the control groups, indicating that the potential predators not only act as predators but also as food competitors, constituting a twofold cost for D. ergandros. 相似文献
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Jake Morris Elizabeth O'Brien Bianca Ambrose-Oji Anna Lawrence Claudia Carter Andrew Peace 《Local Environment》2013,18(4):375-396
This paper presents results from research that identified and analysed barriers to accessing British woodlands and forests. This paper aims to contribute to an understanding of access and accessibility and to inform the design of policy and management interventions to encourage increased access by under-represented social groups. A brief review of policy and academic literature places the issue of inclusive woodland and forest access in the context of contemporary debates surrounding public health, well-being, diversity and the perceived role of public green space. There follows an analysis of quantitative and qualitative research findings, informing the presentation of a working typology of barriers. The typology is structured around the access needs of various social groups, allowing an analysis of the social distribution of barriers. The findings indicate the deep-seated psychological, emotional and socio-cultural nature of some barriers and highlight the need for carefully designed interventions that may lie outside the conventional remit of woodland management. This paper will be of particular interest to decision-makers and practitioners and to those involved in the design and delivery of policies, programmes and projects aimed at encouraging inclusive use of woodlands, forests and other types of green space. 相似文献
16.
Daniela Bueno Sudatti Mutue Toyota Fujii Silvana Vianna Rodrigues Alexander Turra Renato Crespo Pereira 《Marine Biology》2011,158(7):1439-1446
Laurencia dendroidea shows high inter- and intrapopulation variability in the amount of the sesquiterpene elatol, caused by genetic variation
as well as environmental factors. To test the independent effect of physical and nutritional conditions, the growth and the
levels of elatol in L. dendroidea clones were evaluated under different conditions of temperature, salinity, irradiance, and culture medium in the laboratory.
Growth of L. dendroidea was clearly affected by all these factors, but elatol levels were influenced only by temperature and salinity. Better conditions
for growth did not produce a similar effect on elatol production in L. dendroidea, contradicting the carbon/nutrient balance and growth/differentiation balance models. On the contrary, severe conditions
of temperature and salinity promoted a decrease in elatol levels, as predicted by the environmental stress model. Our results
using clones indicated that abiotic factors clearly take part in fostering chemical variations observed in natural populations,
in addition to genetic factors, and can promote differential susceptibility of plant specimens to natural enemies. 相似文献
17.
Christian Turra Carlos Eduardo de Freitas Vian Flávia Angeli Guisi Nielsen Priscilla Silva Santos Luis Fernando de Freitas Penteado 《Journal of Agricultural and Environmental Ethics》2014,27(4):663-679
This study aims to characterize the different types of certification in the Brazilian citriculture as well as analyze the major changes in the market. The paper also has the objective to discuss how social and environmental factors influence the demand for food certifications and the sustainability and ethics aspects in the field. Therefore, a literature review on the subject was carried out as well as a qualitative research using interviews with certifiers, governmental institutions, farmers, cooperatives and producer associations. The certification is becoming mandatory for those working in foreign markets and for those working nationally; it can be a competitive differential. The organic certification in citriculture shows the highest number of growers. Companies with large areas of citrus and the orange juice processing industry are adhering to this certification in order to maintain themselves competitive in the market. There is an enormous potential of Brazilian citriculture certification, because the certified area is still less than 6 % of the total area. Certification reduces the asymmetry of information and consists of an important step towards sustainability although incapable of solely guaranteeing it. 相似文献
18.
Paola Bianca Camisani 《Sustainability Science》2018,13(3):693-707
By analyzing 26 cases in the EJ Atlas for Sri Lanka, their causes, the impacts, the social actors involved, the forms of mobilization, and the main outcomes of the conflicts, this article examines in what ways activities aiming at economic growth produce socio-environmental conflicts. Such activities increase the social metabolism causing changes that translate into environmental, social, and health impacts which due to inequality of power are unequally distributed. As a result, those who are negatively impacted sometimes mobilize claiming environmental justice. The mining of construction materials to support the boom in the building sector and the expansion of intensive plantations into ‘extraction frontiers’ in new territories, cause deforestation, biodiversity loss, and hurt the local communities. Tourism and industries and new infrastructures are causing displacement, pollution, land degradation, and water shortage, affecting communities of farmers and fishermen that mobilize against the adverse impacts. Those with power to appropriate the natural resources are mostly the state together with international finance institutions and international actors who are able to implement the construction of infrastructures, plantations, and mass tourism. Mobilizations are mostly geared to the protection of livelihoods threatened by loss of access to land, pollution, deforestation, diseases, water scarcity, and new uncertain risks. The protection of the environment demanded by the mobilized groups in Sri Lanka does not aim just to protect nature itself but belongs to a wider movement of an “environmentalism of the poor”. 相似文献
19.
Mendes Bruna de Oliveira Rabelo Letícia Martins e Silva Bianca Costa de Souza Joyce Moreira da Silva Castro André Luis da Silva Anderson Rodrigo de Lima Rodrigues Aline Sueli Malafaia Guilherme 《Environmental science and pollution research international》2017,24(23):19234-19248
Environmental Science and Pollution Research - The current study has assessed whether the oral and/or dermal exposure of C57Bl/6 J mice to tannery effluent (a complex pollutant consisting of... 相似文献
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Cauê Bonucci Moreira Ricardo Vieira Rodrigues Luis Alberto Romano Emeline Pereira Gusmão Bianca Hartwig Seyffert Luís André Sampaio Kleber Campos Miranda-Filho 《Environmental science and pollution research international》2014,21(8):5565-5574
Petroleum hydrocarbons are considered one of the main organic chemicals found in water bodies. In the present study, the median lethal concentration (LC50) was estimated for mullet Mugil liza after acute exposure to petroleum water-soluble fraction (PWSF). Furthermore, histopathological studies and micronuclei frequency were also performed in order to observe deleterious effects of medium-term exposition to PWSF. Mullets (25?±?2.3 g) were exposed to chronic concentrations (1.7, 3.5 and 7 % of PWSF), plus the control group, for 14 and 7 days of clearance time. Throughout the experimental period (1, 4, 14 and 21 days), blood samples were collected for analysis of micronucleus (MN) and liver and gills for histopathological study. For these procedures, seven fish were sampled per concentration tested. The LC50-96 h was estimated at 37.5 % of the PWSF. The time required for MN induction was 96 h of exposure. The time of clearance was sufficient to achieve a MN frequency similar to that of the control group. Histopathological studies showed severe changes in the gill and liver tissues. The most relevant histopathology in the gills was telangiectasia. Hepatic histopathology such as cholestasis, dilated sinusoids and inflammatory infiltrates were commonly described. The MN test and histological study effectively detected damages caused by medium-term exposition to the PWSF, and despite the toxicity, a few days without exposure can minimize PWSF genotoxicity in juveniles of M. liza. 相似文献