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1.
J Environ Manage ; 287: 112314, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33740747

RESUMO

Globally, community-based initiatives are effective in protecting ecosystems and the species within them. In this paper, we analyze the emergence and large-scale expansion of a community-based environmental protection system (the Voluntary Environmental Agents Program - VEA Program) in the Brazilian Amazon and identify factors that have determined its success since its inception, 25 years ago. Collective actions to protect the environment in the region have been undertaken by local people for at least 40 years, before their legal regulation in 2001 by the federal government of Brazil, and by the Amazonas state in 2007. The system is based on territorial surveillance and monitoring, and on guidelines for the better use of the territory and its natural resources. Between 1995 and 2020, the VEA Program expanded into the two protected areas where it was first implemented reaching approximately 9 thousand km2 of area protected by the system. The number of people participating also grew in this period by around 2050%, as did the participation of women, which grew by 5600%. The system was replicated in 37 protected areas in central Amazonia, and currently covers almost 200 thousand km2 of Amazon rainforest. From our analyses we unveil four main factors that may have allowed the VEA Program to expand and flourish: (a) the communities' previous demand for an effective control system, (b) its legal formalization and regulation, (c) the support from external institutions, and (d) the consolidation of community-based management programs to fund actions. These factors shall be further investigated as to confirm their critical role in the success of the VEA Program. We demonstrate that this community-based environmental protection system has established itself as a legitimate form of social control, and as a mechanism of socio-environmental governance in the areas in which it operates. By allowing more effective protection of territories, it generates consensus amongst users for the adequate management of natural resources, especially in contexts where government's actions are absent or inefficient. We claim that this system can be replicated in various parts of the world.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Brasil , Política Ambiental , Feminino , Humanos
2.
J Anim Ecol ; 78(6): 1163-71, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19627393

RESUMO

1. River system dynamics results in ecological heterogeneities that play a central role in maintaining biodiversity in riverine regions. In central Amazonia, large expanses of forest are seasonally flooded by nutrient-rich water (várzea forests) or by nutrient-poor water (igapó forests). Inundation patterns and the nutrient load of floodwaters are perhaps the most important abiotic factors determining spatial ecological variations in lowland Amazonia, and so they are expected to strongly influence the structuring of animal communities. 2. We examined how inundation patterns and water-nutrient load influence the structure of neotropical assemblages of bats, one of the most diverse vertebrate groups in tropical forests. Bat assemblages were sampled with mist nets in central Brazilian Amazonia, across a mosaic of várzea, igapó, and non-flooding nutrient-poor terra firme forests in the low- and high-water seasons. 3. An ordination analysis clearly separated the assemblages of the three forest types, demonstrating the structural relevance of both flooding and floodwater-nutrient load. Flooded forests had lower species richness because of the absence or rarity of species that make roosts out of leaves of understorey plants, and of those that feed on fruits of shrubs. Gleaning insectivores, also partly dependent on the understorey, were less abundant in flooded forests, but aerial insectivores more abundant, presumably because they benefited from a less cluttered foraging environment. These differences suggest that flooding affects bat assemblages mostly because it reduces the availability of niches associated with understorey vegetation, which tends to be sparser in flooded forests. 4. Nutrient-rich várzea forests had a bat biomass twice that of nutrient-poor igapó and unflooded forests. This difference was not only mostly due to a greater overall abundance of bats, but also attributable to a disproportionate higher abundance of large-bodied bat species. 5. We concluded that both flooding and floodwater-nutrient load are very important in the structuring of lowland Amazonian bat assemblages, with inundation mostly constraining the species composition of the assemblages, and water-nutrient load mostly influencing the abundance of species. The distinctiveness of bat assemblages associated with flooding emphasizes the need to preserve inundated forests, which are under particular pressure in Amazonia.


Assuntos
Quirópteros/classificação , Quirópteros/fisiologia , Ecossistema , Inundações , Animais , Biomassa , Brasil , Dinâmica Populacional , Estações do Ano
3.
Primates ; 59(4): 395-404, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29525834

RESUMO

Integration between ecology and biogeography provides insights into how niche specialization affects the geographical distribution of species. Given that rivers are not effective barriers to dispersal in three parapatric species of squirrel monkeys (Saimiri vanzolinii, S. cassiquiarensis and S. macrodon) inhabiting floodplain forests of Central Amazonia, we tested whether forest structure and tree diversity may explain species differences in niche specialization and spatial segregation. We sampled 6617 trees of 326 species in three habitats (high várzea, low várzea and chavascal) used by three Saimiri species, and estimated tree species richness in each of them. For each tree, we measured variables known to influence habitat use in primates, such as crown area and presence of lianas, epiphytes and hemi-epiphytes. We used ANOVA to compare these variables and performed multivariate analyses (NMDS, ANOSIM and SIMPER) to evaluate dissimilarities in forest structure among each habitat inhabited by the three Saimiri species. We identified differences in the tree species richness, crown area and presence of lianas, epiphytes and hemi-epiphytes between the three habitats for all Saimiri species. NMDS demonstrated that areas of high and low várzeas occupied by S. vanzolinii were clearly separated from the other species. We also found that different plant species contributed to dissimilarity among Saimiri ranges. Our findings support the hypothesis that tree community structure may promote niche specialization and spatial segregation among primates. We discuss how these patterns could have been favored by historical changes in forest flood patterns, the evolutionary history of Saimiri spp., and past competition.


Assuntos
Distribuição Animal , Ecossistema , Florestas , Saimiri/fisiologia , Animais , Brasil , Simpatria , Árvores/fisiologia
4.
Biota Neotrop. (Online, Ed. ingl.) ; 21(4): e20211207, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1345406

RESUMO

Abstract: The present study reviews the records of occurrences of fish species found in the Mamirauá Sustainable Development Reserve (MSDR). The reserve is located in a large section of the middle Solimões River basin, in its interflow with Japurá River. For the elaboration of the list of fish species occurring in Mamirauá Reserve, we used a database of different studies on fish communities carried out in the area over the last three decades, in addition to the material deposited in the ichthyological collections of three scientific institutions, the National Institute for Amazon Research - INPA, the Mamirauá Sustainable Development Institute - IDSM and the Science and Technology Museum of the Catholic University of Rio Grande do Sul - PUCRS. The ichthyofauna of the MSDR is composed of 541 species, encompassing 45 families and 15 orders. These correspond to 20% of all valid species known for the entire Amazonia so far. As observed in other studies in the Neotropical Region, the more represented orders were Siluriformes (209 species) and Characiformes (185 species), followed by the Gymnotiformes (78 species). The results presented here demonstrate a considerable increase (86%) in the knowledge about the fish diversity found in Mamirauá Reserve, in relation to its first list of fish species, published in the 90's. This increase reflects not only the growth in number of studies on fish diversity in the area, with new surveys, but also the continuous taxonomic work on the collections, and descriptions of twenty-eight new species, with one hundred and ten type series. Further surveys are expected to take place in the Northwestern, more isolated areas of the Reserve, and will allow the identification of new occurrences, and may even unveil new fish species yet to be described to Science..


Resumo: Este estudo apresenta uma revisão dos registros de ocorrências das espécies de peixes encontradas na Reserva de Desenvolvimento Sustentável Mamirauá (RDSM), ampla área localizada na bacia do Médio Solimões, em seu interflúvio com o Rio Japurá. Para a elaboração da lista de peixes que ocorrem na Reserva Mamirauá foram utilizados os bancos de dados de diferentes estudos sobre comunidades de peixes realizados na área ao longo das últimas décadas, além de informações referentes ao material tombado nas coleções ictiológicas de três instituições científicas, o Instituto Nacional de Pesquisas da Amazônia- INPA,o Instituto de Desenvolvimento Sustentável Mamirauá - IDSM e o Museu de Ciências e Tecnologia da Pontifícia Universidade Católica do Rio Grande do Sul - PUCRS. A ictiofauna da RDSM é composta por 541 espécies, incluindo 45 famílias e 15 ordens. Estes valores correspondem a cerca de 20% de todas espécies válidas conhecidas para toda a Amazônia até o momento. Assim como em outros estudos na região Neotropical as ordens que apresentaram as maiores riquezas foram siluriformes (209 espécies) e Characiformes (185 espécies), seguidas de Gymnotiformes (78 espécies). Os resultados apresentados neste trabalho demonstram um aumento considerável (86%) no conhecimento sobre a diversidade de peixes encontrados na Reserva Mamirauá, em relação à primeira lista de peixes da RDSM, publicada na década de 1990. Este aumento reflete não apenas o crescimento no número de estudos sobre a diversidade de peixes na área, com a ocorrência de novos levantamentos, como também a intensificação dos trabalhos taxonômicos de classificação e descrição de vinte oito novas espécies com cento e dez séries tipos. Novos levantamentos deverão ocorrer nas áreas mais isoladas da Reserva, na sua porção noroeste. Estas atividades permitirão a identificação de novas ocorrências, e podem até revelar espécies novas a serem descritas..

5.
Primates ; 55(2): 199-206, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24193509

RESUMO

The white bald uakari (Cacajao calvus calvus) is among the least studied of the Amazonian primates and is found exclusively in remote areas of the central Amazon. The geographic distribution of this subspecies is still uncertain, and information on current threats and its conservation status is sparse. In this paper, we identify new locations of occurrence and propose range expansion of the Cacajao calvus calvus. Between 2008 and 2010, six field expeditions were undertaken in the middle Solimões region to search for the subspecies and to conduct interviews with local residents regarding its presence. The presence of the white bald uakari was confirmed in the lower courses of the Juruá and lower Jutaí rivers, in addition to areas inside the Mamirauá Reserve, where its presence was expected. Results indicate an expansion and new limits on the geographic range of the subspecies, including its detection in areas in which it had not previously been reported and its exclusion from areas where white bald uakaris were assumed to occur. The new information provided by this study and the remaining shortcomings regarding the distribution of the calvus group point to the urgent need for further research on the geographic distribution and habitat use of this group, especially along the lower courses of the Juruá and Jutaí rivers, which remain little explored.


Assuntos
Distribuição Animal , Pitheciidae/fisiologia , Animais , Brasil
6.
Acta amaz ; 40(2): 333-346, 2010. ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: lil-555568

RESUMO

Pirarucu (Arapaima gigas) has been of the most important natural fishing resources of the Amazon region. Due to its economic importance, and the necessity to preserve the species hand, field research concerning the habits and behavior of the pirarucu has been increasing for the last 20 years. The aim of this paper is to present a mathematical model for the pirarucu population dynamics considering the species peculiarities, particularly the male parental care over the offspring. The solution of the dynamical systems indicates three possible equilibrium points for the population. The first corresponds to extinction; the third corresponds to a stable population close to the environmental carrying capacity. The second corresponds to an unstable equilibrium located between extinction and full use of the carrying capacity. It is shown that lack of males' parental care closes the gap between the point corresponding to the unstable equilibrium and the point of stable non-trivial equilibrium. If guarding failure reaches a critical point the two points coincide and the population tends irreversibly to extinction. If some event tends to destabilize the population equilibrium, as for instance inadequate parental care, the model responds in such a way as to restore the trajectory towards the stable equilibrium point avoiding the route to extinction. The parameters introduced to solve the system of equations are partially derived from limited but reliable field data collected at the Mamirauá Sustainable Development Reserve (MSDR) in the Brazilian Amazonian Region.


Pirarucu (Arapaima gigas) tem sido um dos mais importantes recursos pesqueiros naturais da Amazônia. Devido à sua importância econômica, por um lado, e a necessidade de preservar a espécie, por outro lado, o domínio da investigação relativa a hábitos e comportamento do pirarucu tem sido crescente nos últimos 20 anos. O objetivo deste trabalho é apresentar um modelo matemático para a dinâmica populacional do pirarucu considerando as peculiaridades da espécie, particularmente o cuidado parental do macho sobre seus descendentes. A solução dos sistemas dinâmicos indicaram três possíveis pontos de equilíbrio para a população. O primeiro corresponde à extinção; o terceiro corresponde a uma população estável próxima da capacidade suporte do ambiente. O segundo corresponde a um equilíbrio instável localizado entre a extinção e a capacidade suporte do ambiente. Foi mostrado que a falta do cuidado parental de machos aproxima o ponto que corresponde ao equilíbrio instável e o ponto de equilíbrio estável não trivial. Se a falta de cuidado dos machos alcança um ponto crítico, os dois pontos coincidem e a população tende irreversivelmente à extinção. Os parâmetros introduzidos para resolver o sistema de equações foram derivados parcialmente de limitados, mas confiáveis dados de campo coletados na Reserva de Desenvolvimento Sustentável Mamirauá (RDSM) na Amazônia brasileira.


Assuntos
Animais , Dinâmica Populacional , Peixes , Modelos Teóricos , Ecossistema Amazônico
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