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31.
Joël Meunier Susana Figueiredo Pinto Reto Burri Alexandre Roulin 《Behavioral ecology and sociobiology》2011,65(4):559-567
Although melanin is the most common pigment in animal integuments, the adaptive function of variation in melanin-based coloration
remains poorly understood. The individual fitness returns associated with melanin pigments can be variable across species
as these pigments can have physical and biological protective properties and genes involved in melanogenesis may vary in the
intensity of pleiotropic effects. Moreover, dark and pale coloration can also enhance camouflage in alternative habitats and
melanin-based coloration can be involved in social interactions. We investigated whether darker or paler individuals achieve
a higher fitness in birds, a taxon wherein associations between melanin-based coloration and fitness parameters have been
studied in a large number of species. A meta-analysis showed that the degree of melanin-based coloration was not significantly
associated with laying date, clutch size, brood size, and survival across 26 species. Similar results were found when restricting
the analyses to non-sexually dimorphic birds, colour polymorphic and monomorphic species, in passerines and non-passerines
and in species for which inter-individual variation in melanism is due to colour intensity. However, eumelanic coloration
was positively associated with clutch and brood size in sexually dimorphic species and those that vary in the size of black
patches, respectively. Given that greater extent of melanin-based coloration was positively associated with reproductive parameters
and survival in some species but negatively in other species, we conclude that in birds the sign and magnitude of selection
exerted on melanin-based coloration is species- or trait-specific. 相似文献
32.
Philip M. Fearnside Adriano M. R. Figueiredo Sandra C. M. Bonjour 《Environment, Development and Sustainability》2013,15(2):325-338
This paper explores China’s role in deforestation in Latin America. Brazil’s Amazon region contains vast natural resources including land, timber, minerals and hydroelectric potential. China’s strong economy and large demands relative to domestic supplies of these resources mean that China has become Brazil’s largest trading partner, primarily for natural resources. The paper examines how China influences deforestation in Brazilian Amazonia in a variety of ways, including through the direct influence of Chinese enterprises through land purchases and other mechanisms. This paper finds that the rapid rise in exports of soy and beef products to China are two of the major drivers of Amazonian deforestation in Brazil. The paper further argues that Chinese purchases of agricultural and forest land and Chinese imports of commodities such as timber and aluminum also cause environmental impacts in Amazonia. Chinese financing and investment in Amazonian infrastructure such as railways and mineral processing facilities have additional impacts. 相似文献
33.
Bustamante Mercedes M. C. Silva José Salomão Scariot Aldicir Sampaio Alexandre Bonesso Vieira Daniel Luis Mascia Garcia Edenise Sano Edson Fernandes Geraldo Wilson Durigan Giselda Roitman Iris Figueiredo Isabel Rodrigues Ricardo Ribeiro Pillar Valério D. de Oliveira Alba Orli Malhado Ana Claudia Alencar Ane Vendramini Annelise Padovezi Aurélio Carrascosa Helena Freitas Joberto Siqueira José Alves Shimbo Julia Generoso Leonel Graça Tabarelli Marcelo Biderman Rachel de Paiva Salomão Rafael Valle Raul Junior Brienza Nobre Carlos 《Mitigation and Adaptation Strategies for Global Change》2020,25(4):735-736
Mitigation and Adaptation Strategies for Global Change - The original version of the article unfortunately contained an error. 相似文献
34.
Joana Figueiredo Gil Penha-Lopes Justin Anto Luís Narciso Junda Lin 《Marine Biology》2008,154(2):287-294
The present work is a comprehensive study of reproduction and embryonic development of Armases cinereum. Ovigerous A. cinereum (Bosc, 1802) females from Sebastian Inlet, Florida (9.88–19.4 mm CW) lay 2,000–12,000 eggs per brood, depending on their
CW (mm): fecundity = 24.662 CW1.9432. A. cinereum displayed significant brood loss through development (ca. 500 eggs per brood) independently from their CW (no senescence).
However, since smaller females lay fewer eggs than larger ones, the percentage of eggs lost during embryonic development is
greater in smaller females. The number of eggs carried on a later stage of development (potential fertility = 5.5593 CW2.4417) is a more accurate estimate of the reproductive output and subsequent recruitment. Egg volume increased during development
(64%, 0.025–0.041 mm3 or 0.36–0.43 mm of diameter, N = 270) and was strongly correlated with egg water content increase (19.21%, r = 0.89). Lipids, particularly fatty acids, seem to be the major energy source for embryonic development, decreasing 56.31
and 37.08% (respectively) during embryonic development; both are negatively correlated with egg volume (r = −0.90). The utilization of fatty acids through the different developmental stages of A. cinereum is presented. The most consumed fatty acids are the monounsatured (43.33 μg mg−1 dw), followed by the saturated (29.91 μg mg−1 dw) and polyunsaturated (24.03 μg mg−1). Palmitic (16:0) and linoleic (18:2n-6) acids are preferentially consumed (19.5 and 17.9 μg mg−1 dw, respectively). The high proportion of essential polyunsaturated fatty acids of C18 and C20 reflects the consumption of primary producers such as mangrove leaves. EPA/DHA ratio (2.85–3.84) and low DHA content indicated
that this species appears in a medium-low level of the trophic chain. The low ratio of 18:1n-7/18:1n-9 and high percentage of 18:1n-9 (marker of carnivory) may be a sign of the consumption of juvenile invertebrates. The high
percentage of odd-numbered FA indicated the occurrence of detritivores/scavenger behaviours. The fatty acid composition of
the eggs reflects adult feeding ecology (omnivorous) and habitat. 相似文献
35.
Marcela Prado Silva Ana Paula dos Santos Batista Sueli Ivone Borrely Vanessa Honda Ogihara Silva Antonio Carlos Silva Costa Teixeira 《Environmental science and pollution research international》2014,21(21):12135-12142
Photochemical advanced oxidation processes have been considered for the treatment of water and wastewater containing the herbicide atrazine (ATZ), a possible human carcinogen and endocrine disruptor. In this study, we investigated the effects of the photon emission rate and initial concentration on ATZ photolysis at 254 nm, an issue not usually detailed in literature. Moreover, the role of reactive oxygen species (ROS) is discussed. Photon emission rates in the range 0.87?×?1018–3.6?×?1018 photons L?1 s?1 and [ATZ]0?=?5 and 20 mg L?1 were used. The results showed more than 65 % of ATZ removal after 30 min. ATZ photolysis followed apparent first-order kinetics with k values and percent removals decreasing with increasing herbicide initial concentration. A fivefold linear increase in specific degradation rate constants with photon emission rate was observed. Also, regardless the presence of persistent degradation products, toxicity was efficiently removed after 60-min exposure to UV radiation. Experiments confirmed a noticeable contribution of singlet oxygen and radical species to atrazine degradation during photolysis. These results may help understand the behavior of atrazine in different UV-driven photochemical degradation treatment processes. 相似文献
36.
Markert B Wuenschmann S Fraenzle S Graciana Figueiredo AM Ribeiro AP Wang M 《Environmental pollution (Barking, Essex : 1987)》2011,159(8-9):1991-1995
After considering the particular problems of atmospheric pollution in megacities, i.e. agglomerations larger than 5 mio. inhabitants, with urbanization of World's population going on steadily, possibilities of active biomonitoring by means of green plants are discussed. Based on specific definitions of active and passive bioindication the chances of monitoring heavy metals in Sao Paulo megacity were demonstrated (first results published before). This is to show that there is need for increased use of bioindication to tackle the particular problems of megacities concerning environmental "health", the data to be processed according to the Multi-Markered-Bioindication-Concept (MMBC). Comparison to other work shows this approach to be reasonable. 相似文献
37.
Emmanoel V. Silva-Filho Vinicius T. Kütter Thiago S. Figueiredo Emmanuel Tessier Carlos E. Rezende Daniel C. Teixeira Carlos A. Silva Olivier F. X. Donard 《Environmental monitoring and assessment》2014,186(12):8141-8150
Mercury (Hg) is considered a global pollutant, and the scientific community has shown great concern about its toxicity as it may affect the biota of entire systems, through bioaccumulation and bioamplification processes of its organic form, methylmercury (MeHg), along food web. However, few research studies deal with bioaccumulation of Hg from marine primary producers and the first-order consumers. So, this study aims to determine Hg distribution and concentration levels in phytoplankton and zooplankton in the Cabo Frio Bay, Brazil, a site influenced by coastal upwelling. The results from Hg speciation analyses show that inorganic mercury Hg(II) was the predominant specie in plankton from this bay. The annual Hg species distribution in plankton shown mean concentration of 2.00?±?1.28 ng Hg(II)?g?1 and 0.15?±?0.08 ng MeHg g?1 wet weight (phytoplankton) and 2.5?±?2.03 ng Hg(II)?g?1 and 0.25?±?0.09 ng MeHg g?1 wet weight (zooplankton). Therefore, upwelling zones should be considered in the Hg biogeochemical cycle models as a process that enhances Hg(II) bioaccumulation in plankton, raising its bioavailability and shelf deposition. 相似文献
38.
A. P. Ribeiro A. M. G. Figueiredo J. E. S. Sarkis M. A. Hortellani B. Markert 《Environmental monitoring and assessment》2012,184(12):7373-7382
Over the last years, investigations on the increase of platinum (Pt), palladium (Pd), and rhodium (Rh) levels in urban environments of big cities all over the world - especially to catalytic converters emissions - have been grown up enormously. S?o Paulo City is the 6th largest megacity in the world having about 20 million inhabitants and an ever increasing seven million motor vehicle fleet. In spite of this, there has never been an investigation regarding Pt, Pd, and Rh levels in the city. In the present study, Pt, Pd, and Rh concentrations were determined in soils adjacent to seven main high-density traffic avenues in the metropolitan region of S?o Paulo City. Inductively coupled plasma mass spectrometry was employed - after ultrasound-assisted aqua regia leaching - as analytical technigue. The results showed concentration levels up to 378?ng?g?1 for Pd, 208?ng?g?1 for Pt, and 0.2 to 45?ng?g?1 for Rh. These levels are much higher than those considered for the geochemical background of soils, indicating a catalytic converter source. Due to the different Pt/Pd/Rh ratio in Brazilian automobile catalytic converters, lower levels of Pt/Pd ratios compared with other similar studies were observed. The obtained results are the first data for monitoring Pt, Pd, and Rh pollution in S?o Paulo City soils. 相似文献
39.
40.
Celso de Sousa Figueiredo Gomes 《Environmental geochemistry and health》2018,40(5):1739-1765
The use of clay by humans for medicinal and wellness purposes is most probably as old as mankind. Within minerals, due to its ubiquitous occurrence in nature and easy availability, clay was the first to be used and is still used worldwide. Healing clays have been traditionally used by man for therapeutic, nutritional and skin care purposes, but they could impart some important health and skin care risks. For instance, clay particles could adsorb and make available for elimination or excretion any potential toxic elements or toxins being ingested or produced, but they could adsorb and make available for incorporation, through ingestion or through dermal absorption, toxic elements, e.g. heavy metals. Edible clays, a particular case of healing clays, have been traditionally used by man for nutritional and therapeutic purposes. Geophagy, the deliberate soil eating, earth eating, clay eating and pica (medical condition or eating disorder shown by individuals addicted to eat earth substances), has been observed in all parts of the world since antiquity, reflecting cultural practice, religious belief and physiological needs, be they nutritional (dietary supplementation) or as a remedy for disease. This paper pretends to review historical data, basic concepts and functions, as well as benefits and risks of the use of healing clays, in general, for therapeutic and cosmetic purposes, and of edible clays, in particular, for therapeutic purposes. 相似文献