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1.
Sci Rep ; 13(1): 966, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653418

RESUMO

Protected area (PA) extent has increased significantly over the last 150 years globally, but it is yet unclear whether progress in expanding coverage has been accompanied by improved performance in ecological representation. Here, we explore temporal trends in the performance of PA networks in representing > 16,000 vertebrate and plant species in tropical Andean countries based on species bioclimatic niche modelling. We use a randomization analysis to assess whether representation gains over time (1937-2015) are the expected consequence of increasing the overall area of the network or the result of better designed networks. We also explore the impact of climate change on protected-area representation based on projected species distributions in 2070. We found that PAs added in the last three to four decades were better at representing species diversity than random additions overall. Threatened species, amphibians and reptiles are the exception. Species representation is projected to decrease across PAs under climate change, although PA expansions over the last decade (2006-2015) better represented species' future bioclimatic niches than did sites selected at random for most evaluated groups. These findings indicate an unbalanced representation across taxa, and raises concern over under-represented groups, including threatened species, and species' representation under climate change scenarios. However, they also suggest that decisions related to locating protected areas have become more strategic in recent decades and illustrate that indicators tracking representativeness of networks are crucial in PA monitoring frameworks.


Assuntos
Conservação dos Recursos Naturais , Crescimento Demográfico , Animais , Mudança Climática , Espécies em Perigo de Extinção , Anfíbios , Ecossistema , Biodiversidade
2.
Conserv Biol ; 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32390229

RESUMO

In pursuit of socioeconomic development, many countries are expanding oil and mineral extraction into tropical forests. These activities seed access to remote, biologically rich areas, thereby endangering global biodiversity. Here we demonstrate that conservation solutions that effectively balance the protection of biodiversity and economic revenues are possible in biologically valuable regions. Using spatial data on oil profits and predicted species and ecosystem extents, we optimise the protection of 741 terrestrial species and 20 ecosystems of the Ecuadorian Amazon, across a range of opportunity costs (i.e. sacrifices of extractive profit). For such an optimisation, giving up 5% of a year's oil profits (US$ 221 million) allows for a protected area network that retains of an average of 65% of the extent of each species/ecosystem. This performance far exceeds that of the network produced by simple land area optimisation which requires a sacrifice of approximately 40% of annual oil profits (US$ 1.7 billion), and uses only marginally less land, to achieve equivalent levels of ecological protection. Applying spatial statistics to remotely sensed, historic deforestation data, we further focus the optimisation to areas most threatened by imminent forest loss. We identify Emergency Conservation Targets: areas that are essential to a cost-effective conservation reserve network and at imminent risk of destruction, thus requiring urgent and effective protection. Governments should employ the methods presented here when considering extractive led development options, to responsibly manage the associated ecological-economic trade-offs and protect natural capital. Article Impact Statement: Governments controlling resource extraction from tropical forests can arrange production and conservation to retain biodiversity and profits. This article is protected by copyright. All rights reserved.

3.
Biota Neotrop. (Online, Ed. ingl.) ; 20(supl.1): e20190905, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1131963

RESUMO

Abstract: Infrastructure projects and agriculture expansion are increasingly threatening forest conservation in Pará state (Brazil). It becomes necessary to address the implications of these activities on the Amazon complex socio-ecological system, considering both material and non-material aspects of Nature´s Contributions to People (NCP). Multiple studies developed future scenarios for the Amazon, but only a few have focused on discussing positive futures derived from policies and interventions based on conservation and human well-being. Here, we aim at understanding the drivers of forest cover change to produce positive scenarios for the future of the Amazon forest in Pará state. By using the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) conceptual framework, we identified as direct drivers of forest cover change: (i) roads construction; (ii) forest degradation; (iii) hydropower projects; (iv) urban expansion; (v) agriculture and pasture expansion; (vi) rural land occupation; (vii) mining; (viii) climate change. As indirect drivers we identified: (i) energy demand; (ii) population growth; (iii) land prices; (iv) commodity demand; (v) consumption behavior. The development of conservation strategies in the borders of deforested areas is needed given the high demand for Nature´s Contributions to People supply. We also propose policies to address the main drivers of forest cover change, influencing land management and consumption behavior in the state. At last, we envision future positive scenarios that would emerge from policy applications and sustainable actions. Based on our study, we discuss the importance of social learning for developing pathways leading to positive futures that consider the integrity and development of both ecological and social systems.


Resumo: Projetos de infraestrutura e expansão agrícola estão cada vez mais ameaçando a conservação florestal no estado do Pará (Brasil). Assim, torna-se necessário abordar as implicações dessas atividades no complexo sistema sócio ecológico da Amazônia, considerando aspectos materiais e não materiais das Contribuições da Natureza para as Pessoas (NCP).Vários estudos desenvolveram cenários para o futuro da floresta Amazônica, porém poucos foram aqueles focados em discutir futuros positivos, derivados da aplicação de políticas e de intervenções baseadas em estratégias de conservação e de sustentabilidade. Neste trabalho buscamos entender os principais fatores determinantes da mudança na cobertura florestal no estado do Pará, de forma a produzir cenários positivos para o futuro da floresta amazônica nesse estado. A partir da estrutura conceitual proposta pela Plataforma Intergovernamental sobre Biodiversidade e Serviços Ecossistêmicos (IPBES) identificamos as principais pressões diretas e indiretas que influenciam na perda de floresta no estado, e os articulamos em um modelo conceitual. As pressões diretas identificadas foram: (i) construção de estradas; (ii) degradação florestal; (iii) projetos para construção de hidrelétricas; (iv) expansão urbana; (v) expansão da agricultura e da pecuária; (vi) ocupação de terras rurais; (vii) mineração; (viii) mudanças climáticas. As pressões indiretas identificadas foram: (i) demanda por energia; (ii) crescimento populacional; (iii) preços da terra; (iv) demanda por commodities; (v) hábitos de consumo. Assim, evidenciamos a importância do desenvolvimento de estratégias de conservação nas áreas de fronteiras de desmatamento devido à alta demanda e oferta por Contribuições da Natureza para as Pessoas (NCPs). Foram propostas políticas para influenciar mudança no gerenciamento da terra e nos hábitos de consumo de forma a abordar os principais fatores de mudança da cobertura florestal no estado. Por fim, nós construímos cenários futuros positivos que emergiriam da aplicação de políticas e ações voltadas para sustentabilidade da natureza e dos serviços ecossistêmicos. Com base em nossa avaliação, enfatizamos a importância do aprendizado social para que possam ser discutidos os caminhos que levam a futuros positivos, que consideram a integridade e o desenvolvimento tanto dos sistemas sociais quanto dos sistemas ecológicos..

4.
PeerJ ; 7: e8060, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31769445

RESUMO

Anthropogenic threat maps are commonly used as a surrogate for the ecological integrity of rivers in freshwater conservation, but a clearer understanding of their relationships is required to develop proper management plans at large scales. Here, we developed and validated empirical models that link the ecological integrity of rivers to threat maps in a large, heterogeneous and biodiverse Andean-Amazon watershed. Through fieldwork, we recorded data on aquatic invertebrate community composition, habitat quality, and physical-chemical parameters to calculate the ecological integrity of 140 streams/rivers across the basin. Simultaneously, we generated maps that describe the location, extent, and magnitude of impact of nine anthropogenic threats to freshwater systems in the basin. Through seven-fold cross-validation procedure, we found that regression models based on anthropogenic threats alone have limited power for predicting the ecological integrity of rivers. However, the prediction accuracy improved when environmental predictors (slope and elevation) were included, and more so when the predictions were carried out at a coarser scale, such as microbasins. Moreover, anthropogenic threats that amplify the incidence of other pressures (roads, human settlements and oil activities) are the most relevant predictors of ecological integrity. We concluded that threat maps can offer an overall picture of the ecological integrity pattern of the basin, becoming a useful tool for broad-scale conservation planning for freshwater ecosystems. While it is always advisable to have finer scale in situ measurements of ecological integrity, our study shows that threat maps provide fast and cost-effective results, which so often are needed for pressing management and conservation actions.

5.
Ecol Evol ; 6(14): 4997-5012, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27547329

RESUMO

Ecuador will experience a significant expansion of the oil industry in its Amazonian region, one of the most biodiverse areas of the world. In view of the changes that are about to come, we explore the conflicts between oil extraction interests and biodiversity protection and apply systematic conservation planning to identify priority areas that should be protected in different oil exploitation scenarios. First, we quantified the current extent of oil blocks and protected zones and their overlap with two biodiversity indicators: 25 ecosystems and 745 species (whose distributions were estimated via species distribution models). With the new scheme of oil exploitation, oil blocks cover 68% (68,196 km(2)) of the Ecuadorian Amazon; half of it occupied by new blocks open for bids in the southern Amazon. This region is especially vulnerable to biodiversity losses, because peaks of species diversity, 19 ecosystems, and a third of its protected zones coincide spatially with oil blocks. Under these circumstances, we used Marxan software to identify priority areas for conservation outside oil blocks, but their coverage was insufficient to completely represent biodiversity. Instead, priority areas that include southern oil blocks provide a higher representation of biodiversity indicators. Therefore, preserving the southern Amazon becomes essential to improve the protection of Amazonian biodiversity in Ecuador, and avoiding oil exploitation in these areas (33% of the extent of southern oil blocks) should be considered a conservation alternative. Also, it is highly recommended to improve current oil exploitation technology to reduce environmental impacts in the region, especially within five oil blocks that we identified as most valuable for the conservation of biodiversity. The application of these and other recommendations depends heavily on the Ecuadorian government, which needs to find a better balance between the use of the Amazon resources and biodiversity conservation.

6.
PLoS One ; 9(12): e114367, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25479411

RESUMO

Conservation planning is crucial for megadiverse countries where biodiversity is coupled with incomplete reserve systems and limited resources to invest in conservation. Using Peru as an example of a megadiverse country, we asked whether the national system of protected areas satisfies biodiversity conservation needs. Further, to complement the existing reserve system, we identified and prioritized potential conservation areas using a combination of species distribution modeling, conservation planning and connectivity analysis. Based on a set of 2,869 species, including mammals, birds, amphibians, reptiles, butterflies, and plants, we used species distribution models to represent species' geographic ranges to reduce the effect of biased sampling and partial knowledge about species' distributions. A site-selection algorithm then searched for efficient and complementary proposals, based on the above distributions, for a more representative system of protection. Finally, we incorporated connectivity among areas in an innovative post-hoc analysis to prioritize those areas maximizing connectivity within the system. Our results highlight severe conservation gaps in the Coastal and Andean regions, and we propose several areas, which are not currently covered by the existing network of protected areas. Our approach helps to find areas that contribute to creating a more representative, connected and efficient network.


Assuntos
Algoritmos , Biodiversidade , Conservação dos Recursos Naturais/métodos , Modelos Biológicos , Animais , Peru
7.
Ecol Evol ; 4(12): 2410-22, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25360277

RESUMO

Ecuador has the largest number of species by area worldwide, but also a low representation of species within its protected areas. Here, we applied systematic conservation planning to identify potential areas for conservation in continental Ecuador, with the aim of increasing the representation of terrestrial species diversity in the protected area network. We selected 809 terrestrial species (amphibians, birds, mammals, and plants), for which distributions were estimated via species distribution models (SDMs), using Maxent. For each species we established conservation goals based on conservation priorities, and estimated new potential protected areas using Marxan conservation planning software. For each selected area, we determined their conservation priority and feasibility of establishment, two important aspects in the decision-making processes. We found that according to our conservation goals, the current protected area network contains large conservation gaps. Potential areas for conservation almost double the surface area of currently protected areas. Most of the newly proposed areas are located in the Coast, a region with large conservation gaps and irreversible changes in land use. The most feasible areas for conservation were found in the Amazon and Andes regions, which encompass more undisturbed habitats, and already harbor most of the current reserves. Our study allows defining a viable strategy for preserving Ecuador's biodiversity, by combining SDMs, GIS-based decision-support software, and priority and feasibility assessments of the selected areas. This approach is useful for complementing protected area networks in countries with great biodiversity, insufficient biological information, and limited resources for conservation.

8.
Rev Biol Trop ; 59(2): 795-807, 2011 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-21721239

RESUMO

Recent phylogenetic studies based on cytochrome b gene sequence, have determined that the species historically known as Sigmodon hispidus (Rodentia) from South America comprises a species S. hirsutus of paraphyletic origin. The aim of this study was to test the hypothesis that populations from Venezuela, represent the sensu strict form, ancestral haplotypes, and monophyletic subspecieS. For this, 12 individual sequences from three localities of different biogeographic regions in Venezuela were evaluated and sequenced based on cyto b. Additionally, the sequences were used to develop a cladistic analysis and genetic distance calculations, and to compare this information with two individual sequences of Sigmodon specimens available in Genbank. Phylogenetic analyses show that the three populations of S. hirsutus of Venezuela form an ancestral and monophyletic subclade supported by high bootstrap values and significant genetic distance between subclade within the S. hirsutus. Besides, the existence of two lineages suggests two subspecies, S. hirsutus hirsutus from Venezuela, and S. hirsutus mexicanus from Mexico-Central America, but, both species need formal description.


Assuntos
Citocromos b/genética , Variação Genética/genética , Sigmodontinae/genética , Animais , Sequência de Bases , Dados de Sequência Molecular , Filogenia , Filogeografia , Análise de Sequência de DNA , Venezuela
9.
Rev. biol. trop ; 59(2): 795-807, jun. 2011. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-638121

RESUMO

Molecular characterization of Sigmodon hirsutus (Rodentia: Cricetidae) populations in Venezuela. Recent phylogenetic studies based on cytochrome b gene sequence, have determined that the species historically known as Sigmodon hispidus (Rodentia) from South America comprises a species S. hirsutus of paraphyletic origin. The aim of this study was to test the hypothesis that populations from Venezuela, represent the sensu strict form, ancestral haplotypes, and monophyletic subspecies. For this, 12 individual sequences from three localities of different biogeographic regions in Venezuela were evaluated and sequenced based on cyto b. Additionally, the sequences were used to develop a cladistic analysis and genetic distance calculations, and to compare this information with two individual sequences of Sigmodon specimens available in Genbank. Phylogenetic analyses show that the three populations of S. hirsutus of Venezuela form an ancestral and monophyletic subclade supported by high bootstrap values and significant genetic distance between subclade within the S. hirsutus. Besides, the existence of two lineages suggests two subspecies, S. hirsutus hirsutus from Venezuela, and S. hirsutus mexicanus from Mexico-Central America, but, both species need formal description. Rev. Biol. Trop. 59 (2): 795-807. Epub 2011 June 01.


Recientes estudios filogenéticos basados en la secuencia del gen del citocromo b, han determinado que la especie conocida históricamente como Sigmodon hispidus (Rodentia) en Suramérica incluye una especie S. hirsutus de origen parafilético. El objetivo de este estudio fue probar la hipótesis de que las poblaciones de Venezuela, representan la forma sensu estricto, los haplotipos ancestrales y una subespecie monofilética. La metodología consistió en un análisis cladístico y cálculos de distancia genética, a partir de secuencias de citocromo b en 12 individuos de tres localidades en Venezuela que pertenecen a diferentes regiones biogeográficas, y a su vez compararlas con las dos secuencias disponibles en Genbank de especies del género Sigmodon. Los análisis filogenéticos indican que las tres poblaciones de S. hirustus de Venezuela forman un subclado ancestral y monofilético con el apoyo de valores de bootstrap altos y con significativa distancia genética, entre subclados dentro de S. hirsutus. La existencia de dos subclados dentro de S. hirsutus sugiere dos subespecies, S. hirsutus hirsutus en Venezuela y S. hirsutus mexicanus en México y Centroamérica. Sin embargo, ambas subespecies necesitan una descripción formal.


Assuntos
Animais , Citocromos b/genética , Variação Genética/genética , Sigmodontinae/genética , Sequência de Bases , Dados de Sequência Molecular , Filogenia , Filogeografia , Análise de Sequência de DNA , Venezuela
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