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1.
Curr Biol ; 33(16): 3495-3504.e4, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37473761

RESUMO

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%-18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost.


Assuntos
Biodiversidade , Florestas , Humanos , Floresta Úmida , Brasil , Clima Tropical , Conservação dos Recursos Naturais , Ecossistema
2.
Environ Manage ; 72(3): 540-557, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37060368

RESUMO

Analysis of small-scale inland fisheries (SSIFs) is often highly dispersed and tends not reflect the true magnitude of their contribution to society. This is partly due to the insufficient attention given to this sector by the relevant authorities, in addition to its highly diverse characteristics, with complex patterns of operation in a wide range of systems, often in remote areas. Here, by integrating fishers as participatory fishery monitors, we provide fishery-dependent estimates of yields, the biological attributes of the fish species, and the spatiotemporal dynamics of the fisheries of lakes on the floodplain of the São Francisco basin in northeastern Brazil. As the fishers were willing participates in the monitoring, the results revealed well-structured artisanal fishing activities, with the lake system providing high-profile fish harvests from both monthly and annual perspectives. The spatial distribution of fishing effort reflected the adaptation of the fishers to the flood cycle of the river, in order to maintain high fishery productivity throughout the year. The results also indicate that participatory monitoring can help to overcome knowledge gaps and provide a database that is readily applicable to management needs at both local and regional scales. As Brazil is one few world's nations that no longer have national fishing monitoring program, participatory monitoring represents a low-cost solution for the credible and useful data on small-scale fisheries. It would thus appear to be extremely worthwhile to invest in the empowerment of communities in order to overcome the historic vulnerability of productive sector and the food security of the populations that depend on these fisheries.


Assuntos
Pesqueiros , Rios , Animais , Brasil , Conhecimento , Lagos , Peixes , Conservação dos Recursos Naturais/métodos
3.
Environ Manage ; 68(4): 445-452, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34341867

RESUMO

The Tocantins-Araguaia Basin is one of the largest river systems in South America, located entirely within Brazilian territory. In the last decades, capital-concentrating activities such as agribusiness, mining, and hydropower promoted extensive changes in land cover, hydrology, and environmental conditions. These changes are jeopardizing the basin's biodiversity and ecosystem services. Threats are escalating as poor environmental policies continue to be formulated, such as environmentally unsustainable hydropower plants, large-scale agriculture for commodity production, and aquaculture with non-native fish. If the current model persists, it will deepen the environmental crisis in the basin, compromising broad conservation goals and social development in the long term. Better policies will require thought and planning to minimize growing threats and ensure the basin's sustainability for future generations.


Assuntos
Ecossistema , Rios , Animais , Biodiversidade , Conservação dos Recursos Naturais , Política Ambiental
4.
Science ; 370(6512): 117-121, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33004520

RESUMO

Conservation initiatives overwhelmingly focus on terrestrial biodiversity, and little is known about the freshwater cobenefits of terrestrial conservation actions. We sampled more than 1500 terrestrial and freshwater species in the Amazon and simulated conservation for species from both realms. Prioritizations based on terrestrial species yielded on average just 22% of the freshwater benefits achieved through freshwater-focused conservation. However, by using integrated cross-realm planning, freshwater benefits could be increased by up to 600% for a 1% reduction in terrestrial benefits. Where freshwater biodiversity data are unavailable but aquatic connectivity is accounted for, freshwater benefits could still be doubled for negligible losses of terrestrial coverage. Conservation actions are urgently needed to improve the status of freshwater species globally. Our results suggest that such gains can be achieved without compromising terrestrial conservation goals.


Assuntos
Organismos Aquáticos , Conservação dos Recursos Naturais , Rios , Animais , Biodiversidade , Brasil
5.
Glob Chang Biol ; 22(3): 990-1007, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26700407

RESUMO

Hydrological connectivity regulates the structure and function of Amazonian freshwater ecosystems and the provisioning of services that sustain local populations. This connectivity is increasingly being disrupted by the construction of dams, mining, land-cover changes, and global climate change. This review analyzes these drivers of degradation, evaluates their impacts on hydrological connectivity, and identifies policy deficiencies that hinder freshwater ecosystem protection. There are 154 large hydroelectric dams in operation today, and 21 dams under construction. The current trajectory of dam construction will leave only three free-flowing tributaries in the next few decades if all 277 planned dams are completed. Land-cover changes driven by mining, dam and road construction, agriculture and cattle ranching have already affected ~20% of the Basin and up to ~50% of riparian forests in some regions. Global climate change will likely exacerbate these impacts by creating warmer and dryer conditions, with less predictable rainfall and more extreme events (e.g., droughts and floods). The resulting hydrological alterations are rapidly degrading freshwater ecosystems, both independently and via complex feedbacks and synergistic interactions. The ecosystem impacts include biodiversity loss, warmer stream temperatures, stronger and more frequent floodplain fires, and changes to biogeochemical cycles, transport of organic and inorganic materials, and freshwater community structure and function. The impacts also include reductions in water quality, fish yields, and availability of water for navigation, power generation, and human use. This degradation of Amazonian freshwater ecosystems cannot be curbed presently because existing policies are inconsistent across the Basin, ignore cumulative effects, and overlook the hydrological connectivity of freshwater ecosystems. Maintaining the integrity of these freshwater ecosystems requires a basinwide research and policy framework to understand and manage hydrological connectivity across multiple spatial scales and jurisdictional boundaries.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Água Doce/análise , Agricultura , Mudança Climática , Hidrologia , Mineração , Rios , América do Sul
6.
Science ; 344(6188): 1118-23, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24904156

RESUMO

The recent 70% decline in deforestation in the Brazilian Amazon suggests that it is possible to manage the advance of a vast agricultural frontier. Enforcement of laws, interventions in soy and beef supply chains, restrictions on access to credit, and expansion of protected areas appear to have contributed to this decline, as did a decline in the demand for new deforestation. The supply chain interventions that fed into this deceleration are precariously dependent on corporate risk management, and public policies have relied excessively on punitive measures. Systems for delivering positive incentives for farmers to forgo deforestation have been designed but not fully implemented. Territorial approaches to deforestation have been effective and could consolidate progress in slowing deforestation while providing a framework for addressing other important dimensions of sustainable development.


Assuntos
Conservação dos Recursos Naturais/tendências , Glycine max/provisão & distribuição , Carne/provisão & distribuição , Política Pública , Animais , Brasil , Bovinos , Humanos
7.
Environ Manage ; 43(2): 197-209, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18946698

RESUMO

Fishers and small-scale fisheries worldwide have been marginalized historically. Now it is clear that integrating fishers in management processes is key to resource conservation, but it is less clear how to do it. Here, based on a literature review and new information, we present and analyze a case in which the participation of fishers in the management process was crucial in recovering an overexploited small-scale fishery for the pirarucu (Arapaima spp.) in the Amazon Basin, Brazil. In 8 years of experimental management, from 1999 to 2006, the population of pirarucu increased 9-fold (from about 2200 to 20,650 individuals), harvest quotas increased 10-fold (from 120 to 1249 individuals), and fishers' participation in the management process increased and they benefited from increased monetary returns. Additionally, the number of communities conducting the management scheme increased from 4 in 1999 to 108 in 2006, following the demands of fishers and regional government agencies. Based on our analysis, we suggest that the participation of fishers in the management of other small-scale fisheries in the world can be improved by focusing on (1) applying the knowledge and skills of fishers in resource monitoring and management, (2) bridging knowledge systems among all involved stakeholders, (3) collaborating with fishers that are interested in, and capable of conducting, resource conservation schemes, and (4) conducting management under conditions of uncertainty.


Assuntos
Participação da Comunidade/métodos , Conservação dos Recursos Naturais/métodos , Pesqueiros/métodos , Peixes/crescimento & desenvolvimento , Animais , Brasil , Pesqueiros/economia , Humanos , Dinâmica Populacional , Rios
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