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1.
Mar Pollut Bull ; 164: 111984, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33517088

RESUMO

In August 2019, a major oil spill hit nine Brazilian coastal states, affecting marine ecosystems and fishing communities. In this study, we assess the immediate social and economic impacts of this oil spill on fishing communities of the northeast coast. We conducted semi-structured interviews and focal meetings with 381 fishers and shellfish gatherers to understand the perceived socioeconomic impacts on different types of fishing. We also obtained information on fish consumption after the oil spill, which we compared with data prior to the oil spill from the same communities. Sales decreased by more than 50% for all types of fishing, strongly impacting local income generation. These communities, which are already social-ecologically vulnerable, have had their subsistence, food security and cultural maintenance strongly compromised. We argue that there is a clear need for coordinated state interventions to mitigation the impacts, considering it's environmental, social, economic, human health and political dimensions.


Assuntos
Poluição por Petróleo , Animais , Brasil , Ecossistema , Pesqueiros , Humanos , Alimentos Marinhos
2.
Sci Total Environ ; 705: 135717, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31838428

RESUMO

The semi-arid region of Northeast Brazil (NEB) experiences severe droughts during El Niño Southern Oscillation (ENSO) years, with major impacts on the dynamics of the native vegetation (Caatinga). However, the effect of these droughts on carbon cycling is not well understood. Here, a numerical model is used to investigate the influence of variations in Pacific and Atlantic sea surface temperatures (SST) on drought and carbon dynamics of the Caatinga during past ENSO events. We demonstrate that precipitation reductions in the Caatinga have a strong influence on vegetation dynamics, with net primary production (NPP) remaining low throughout the droughts. Furthermore, the Caatinga acts as a carbon sink, even in years of severe drought. However, net ecosystem exchange (NEE) is lower in years of low NPP rates, resulting in long periods with limited ecosystem activity. The SST patterns indicate that extreme vegetation changes in the Caatinga are associated with the combination of ENSO events and North Atlantic SST warming.


Assuntos
El Niño Oscilação Sul , Florestas , Brasil , Oceano Pacífico
3.
Anim Sci J ; 84(4): 289-95, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23590501

RESUMO

The objective of this study was to evaluate the influence of inbreeding depression on traits of buffaloes from Brazil. Specifically, the traits studied were body weight at 205 and 365 days of age, average daily gain from birth to 205 days (ADG_205), average daily gain between 205 and 365 days (ADG205_365) in Mediterranean buffaloes, and milk yield, lactation length, age of first calving and calving intervals in Murrah buffaloes. Inbreeding effects on the traits were determined by fitting four regression models (linear, quadratic, exponential and Michaelis-Menten) about the errors generated by the animal model. The linear model was only significant (P < 0.05) for growth traits (exception of ADG205_365). The exponential and Michaelis-Menten models were significant (P < 0.01) for all the studied traits while the quadratic model was not significant (P > 0.05) for any of the traits. Weight at 205 and 365 days of age decreased 0.25 kg and 0.39 kg per 1% of increase in inbreeding, respectively. The inbred animals (F = 0.25) produced less milk than non-inbred individuals: 50.4 kg of milk. Moreover, calving interval increased 0.164 days per 1% of increase in inbreeding. Interestingly, inbreeding had a positive effect on age at first calving and lactation length, decreasing age of first calving and increasing lactation length.


Assuntos
Búfalos/crescimento & desenvolvimento , Búfalos/genética , Endogamia , Reprodução/genética , Aumento de Peso/fisiologia , Animais , Peso Corporal , Brasil , Feminino , Lactação/genética , Modelos Estatísticos , Gravidez , Aumento de Peso/genética
4.
Trop Anim Health Prod ; 44(8): 1891-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22535150

RESUMO

The objective of this study was to use pedigree analysis to evaluate the population structure and genetic variability in the Murrah dairy breed of water buffalo (Bubalus bubalis) in Brazil. Pedigree analysis was performed on 5,061 animals born between 1972 and 2002. The effective number of founders (fe) was 60, representing 6.32 % of the potential number of founders. The effective number of ancestors (fa) was 36 and the genetic contribution of the 17 most influent ancestors explained 50 % of the genetic variability in the population. The ratio fe/fa (effective number of founders/effective number of ancestors), which expresses the effect of population bottlenecks, was 1.66. Completeness level for the whole pedigree was 76.8, 49.2, 27.7, and 12.8 % for, respectively, the first, second, third, and fourth known parental generations. The average inbreeding values for the whole analyzed pedigree and for inbreed animals were, respectively, 1.28 and 7.64 %. The average relatedness coefficient between individuals of the population was estimated to be 2.05 %-the highest individual coefficient was 10.31 %. The actual inbreeding and average relatedness coefficient are probably higher than estimated due to low levels of pedigree completeness. Moreover, the inbreeding coefficient increased with the addition of each generation to the pedigree, indicating that incomplete pedigrees tend to underestimate the level of inbreeding. Introduction of new sires with the lowest possible average relatedness coefficient and the use of appropriate mating strategies are recommended to keep inbreeding at acceptable levels and increase the genetic variability in this economically important species, which has relatively low numbers compared to other commercial cattle breeds. The inclusion of additional parameters, such as effective number of founders, effective number of ancestors, and fe/fa ratio, provides better resolution as compared to the inclusion of inbreeding coefficient and may help breeders and farmers adopt better precautionary measures against inbreeding depression and other deleterious genetic effects.


Assuntos
Búfalos/genética , Variação Genética , Endogamia , Linhagem , Animais , Brasil , Indústria de Laticínios , Feminino , Efeito Fundador , Masculino , Densidade Demográfica , Dinâmica Populacional
6.
Ciênc. rural ; 40(6): 1385-1391, jun. 2010. tab, ilus
Artigo em Inglês | LILACS | ID: lil-554629

RESUMO

This paper provides an evaluation of the population structure, phenotype and genetic trends of registered Gyr herd cattle in northeast Brazil. The study provides important baseline information for the management, conservation and potential population expansion of this economically and culturally important cattle breed. Pedigree data were analyzed for individuals born between 1964 and 2006. Body weight values were adjusted to 205 and 365 days of age for animals born between 1978 and 2006. Phenotypic change of zebu Gyr in northeast Brazil is solely due to environmental improvement. However, there is potential for artificial selection for weight gain in young cattle. Effective population size decreased during the 1990s and the average inbreeding coefficient increased during the studied period. An increase of the effective population size of Gyr in northeast Brazil is strongly recommended, along with an increase in the management of the mating process to prevent inbreeding and to maintain the genetic variability of the breed.


Com o intuito de fornecer subsídios para programas de conservação, seleção e expansão da raça Gir no Nordeste do Brasil, objetivou-se avaliar o histórico do rebanho Gir registrado no nordeste brasileiro, com base na sua estrutura populacional e no progresso genético e fenotípico de características de desenvolvimento ponderal. Foram utilizadas informações de pedigree de animais nascidos no período de 1964 a 2006 e dados dos pesos ajustados aos 205 e 365 dias de idade de bovinos nascidos de 1978 a 2006. O progresso genético para a raça no Nordeste foi ocasionado exclusivamente pelo melhoramento ambiental. O tamanho efetivo da população reduziu a partir da década de 90, e o coeficiente de endogamia médio aumentou durante o período estudado. É imprescindível que o tamanho efetivo da raça Gir do nordeste seja ampliado e que haja maior controle de acasalamentos entre indivíduos aparentados, para prevenção da endogamia e conservação da variabilidade genética e viabilidade da raça.

7.
Acta amaz ; 40(2): 319-324, 2010. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: lil-555556

RESUMO

The Amazon rainforest stretches across more than six million square kilometers and nine countries. Of the original forest area it is thought that 18 per cent has been cleared, mainly for farming purposes. In Brazil, the main drivers of deforestation are beef ranching and soya production that together occupy more than 75 per cent of newly deforested land. The situation in the Amazon illustrates a fundamental dilemma facing environmentalists around the world: how to reconcile economic development with biodiversity conservation. In this paper the representation of this dilemma in the British and Brazilian news media is assessed. The results indicate that there were far more articles referring to deforestation in the Brazilian press (816 Brazilian to 29 UK) but that many of these make no mention of what factors are responsible for deforestation. The patterns of representation of the proximate (direct) causes of Amazonian deforestation were very similar in the two countries, with soya and beef cattle ranching commanding the most press attention. The ultimate (indirect) causes of deforestation, however, are treated very differently, with the Brazilian media seemingly far more aware of the role of economic development needs than the UK press. Interestingly, the role of international demand for soya, beef, and forest products in driving deforestation was highlighted primarily in the UK press. These findings are critically discussed in the context of media influence on public understandings of Amazonian deforestation.


A floresta Amazônica abrange mais de 6 milhões de km² e engloba 9 países. Acredita-se que 18% da superficie florestal já tenha sido desmatada principalmente para usos agropecuários. No Brasil, a pecuária e a produção de soja encabeçam as causas do desmatamento, sendo estes responsáveis por 75% das terras desmatadas. A situação da Amazônia ilustra o principal dilema que enfrentam os ambientalistas em todo o mundo: como permitir um desenvolvimento econômico que mantenha a biodiversidade. Este estudo examina a representação deste dilema na mídia britânica e brasileira. Foram encontrados 816 artigos nos jornais brasileiros e apenas 29 nos jornais britânicos. No entanto, a grande maioria dos artigos não discutem as causas do desmatamento. A representação das causas diretas do desmatamento é extremamente similar nos dois países sendo soja e pecuária os principais fatores apontados pela mídia. Entretanto, os fatores secundários são tratados diferentemente, sendo que a mídia brasileira mostra como principal fator a necessidade de desenvolvimento econômico. Por outro lado, o papel da demanda internacional da soja, carne e produtos florestais como causas do desmatamento foi bastante discutida na mídia inglesa. Os resultados destas representações em relação a influência que a mídia exerce no entendimento do desmatamento da Amazônia são discutidos.


Assuntos
Ecossistema Amazônico , Conservação dos Recursos Naturais/estatística & dados numéricos , Indicadores de Desenvolvimento , Internacionalidade , Mídias Sociais , Brasil , Reino Unido
8.
Acta amaz ; 35(2): 231-238, abr.-jun. 2005. mapas, tab, graf
Artigo em Inglês | LILACS | ID: lil-413338

RESUMO

A mais severa seca nos trópicos da América do Sul durante o século 20 ocorreu em 1926. Este ano extremo de El Niño é documentado nos níveis de observações do rio (Negro) em Manaus, nos registros anuais de precipitação e anedoticamente. A anomalia anual de precipitação é um dipolo leste-oeste sobre os trópicos da América do Sul, com seca a oeste sobre a bacia Amazônica cuja a descarga é documentada em Manaus, e um residuo para o leste incluindo a região nordeste do Brasil. Especulações sobre a função dos aerosóis na agravação da seca são discutidos.


Assuntos
Precipitação Atmosférica , Secas
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