Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Conserv Biol ; 37(5): e14075, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36786044

RESUMO

Comprehensive biodiversity assessments play an essential role in strengthening global and national conservation strategies. The recently announced first U.S. National Nature Assessment (NNA) provides an unparalleled opportunity to comprehensively review status and trends of biodiversity at all levels. This broad context can help in the coordination of actions to conserve individual species and ecosystems. The scientific assessments that informed the Kunming-Montreal Global Biodiversity Framework adopted at the 2022 Convention on Biological Diversity (CBD) conference of parties provide models for synthesizing information on trends at multiple levels of biodiversity, including decline in abundance and distribution of species, loss of populations and genetic diversity, and degradation and loss of ecosystems and their services. The assessments then relate these trends to data on drivers of biodiversity loss and pathways to their mitigation. The U.S. NNA can augment such global analyses and avoid the pitfalls encountered by previous U.S. efforts by ensuring policy-relevant design, data accessibility, and inclusivity in process and product and by incorporating spatial data relevant to national and subnational audiences. Although the United States is not formally a CBD party, an effective NNA should take full advantage of the global context by including indicators adopted at the 2022 meeting and incorporating an independent review mechanism that supports periodic stocktaking and ratcheting up of ambition in response to identified shortfalls in stemming biodiversity loss. The challenges to design of an effective U.S. assessment are relevant globally as nations develop assessments and reporting to support the new global biodiversity framework's targets. By considering and incorporating the diverse ways in which society values and benefits from nature, such assessments can help bridge the gap between research and conservation practice and communicate the extent of the biodiversity crisis to the public, fostering broad-based support for transformative change in humanity's relationship to the natural world.


Cuatro obstáculos para una eficaz evaluación nacional de la naturaleza Resumen Las evaluaciones completas de la biodiversidad tienen un papel esencial en el fortalecimiento de las estrategias de conservación nacional y mundial. La recién anunciada Evaluación Nacional de la Naturaleza (ENN) de los EE. UU. proporciona una oportunidad sin precedentes para revisar de manera completa el estado y las tendencias de la biodiversidad en todos los niveles. Este contexto generalizado puede ayudar a la coordinación de acciones para la conservación de especies individuales y ecosistemas. Las evaluaciones científicas que guiaron el Marco Mundial de la Biodiversidad de Kumming-Montreal adoptado en la conferencia de las partes de la Convención sobre la Diversidad Biológica (CBD) de 2022 proporcionan modelos para sintetizar la información sobre las tendencias de la biodiversidad a varios niveles, incluyendo la declinación en abundancia y distribución de especies, pérdida de poblaciones y diversidad genética y la degradación y pérdida de los ecosistemas y sus servicios. Después de esto, las evaluaciones relacionan estas tendencias con la información sobre los causantes de la pérdida de la biodiversidad y las maneras de mitigarla. La ENN de los EE. UU. pueden aumentar estos análisis mundiales y evitar las dificultades enfrentadas por los esfuerzos previos al garantizar un diseño relevante para las políticas, la disponibilidad de datos y la inclusión en el proceso y el producto y también mediante la incorporación de datos espaciales relevantes para el público nacional y subnacional. Aunque los EE. UU. no son una parte formal de la CBD, una ENN efectiva debería aprovechar de lleno el contexto global al incluir los indicadores adoptados en la reunión de 2022 e incorporar un mecanismo independiente de revisión que respalde el balance periódico y el aumento de la ambición en respuesta a las deficiencias detectadas en la contención de la pérdida de biodiversidad. Los retos para diseñar una evaluación estadunidense son relevantes a nivel mundial ya que los países evalúan y reportan para mantener los objetivos mundiales de biodiversidad post-2020. Si consideramos las diferentes maneras en las que la sociedad valora y se beneficia de la naturaleza, dichas evaluaciones pueden ayudar a cerrar la brecha entre la investigación y la práctica de la conservación y a comunicarle al público el nivel de la crisis de la biodiversidad, lo que fomenta el apoyo generalizado para transformar la relación entre la humanidad y el mundo natural.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Políticas
2.
Conserv Biol ; 36(4): e13869, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34856009

RESUMO

Global targets for the percentage area of land protected, such as 30% by 2030, have gained increasing prominence, but both their scientific basis and likely effectiveness have been questioned. As with emissions-reduction targets based on desired climate outcomes, percentage-protected targets combine values and science by estimating the area over which conservation actions are required to help achieve desired biodiversity outcomes. Protected areas are essential for achieving many biodiversity targets, in part because many species are highly sensitive to human-associated disturbance. However, because the contribution of protected areas to biodiversity outcomes is contingent on their location, management, governance, threats, and what occurs across the broader landscape matrix, global percentage-protected targets are unavoidably empirical generalizations of ecological patterns and processes across diverse geographies. Percentage-protected targets are insufficient in isolation but can complement other actions and contribute to biodiversity outcomes within a framework that balances accuracy and pragmatism in a global context characterized by imperfect biodiversity data. Ideally, percentage-protected targets serve as anchors that strengthen comprehensive national biodiversity strategies by communicating the level of ambition necessary to reverse current trends of biodiversity loss. If such targets are to fulfill this role within the complex societal process by which both values and science impel conservation actions, conservation scientists must clearly communicate the nature of the evidence base supporting percentage-protected targets and how protected areas can function within a broader landscape managed for sustainable coexistence between people and nature. A new paradigm for protected and conserved areas recognizes that national coordination, incentives, and monitoring should support rather than undermine diverse locally led conservation initiatives. However, the definition of a conserved area must retain a strong focus on biodiversity to remain consistent with the evidence base from which percentage-protected targets were originally derived.


RESUMEN: Las metas globales del porcentaje de área de suelo protegido, como el de 30% para el 2030, han obtenido una prominencia incrementada, a pesar de que se les cuestionen sus bases científicas y la probabilidad de su efectividad. Así como las metas de reducción de emisiones, las metas de porcentaje de protección combinan valores y ciencia mediante la estimación del área que requiere acciones de conservación para ayudar a lograr los resultados deseados de biodiversidad. Las áreas protegidas son esenciales para alcanzar muchas metas de biodiversidad, en parte porque muchas especies son altamente sensibles a las perturbaciones asociadas con el humano. Sin embargo, debido a que la contribución de las áreas protegidas a los resultados de biodiversidad depende de su ubicación, gestión, manejo, amenazas y lo que ocurra a lo largo de la amplia matriz del paisaje, las metas de porcentaje de protección son generalizaciones empíricas inevitables de los patrones y procesos ecológicos en la geografía diversa. Las metas de porcentaje de protección son insuficientes por sí solas, pero pueden complementar a otras acciones y contribuir a los resultados de biodiversidad dentro de un marco de trabajo que balancee la exactitud y el pragmatismo dentro de un contexto global caracterizado por datos imperfectos de la biodiversidad. Idealmente, las metas de porcentaje de protección fungen como pilares que fortalecen las estrategias nacionales integrales de biodiversidad mediante la comunicación del nivel de ambición necesaria para revertir las tendencias actuales de pérdida de la biodiversidad. Si se espera que dichas metas realicen este papel dentro del complejo proceso social en el que tanto los valores como la ciencia impulsan las acciones de conservación, los científicos de la conservación deben comunicar claramente la naturaleza de la base de evidencias que respalda las metas de porcentaje de protección y cómo las áreas protegidas pueden funcionar dentro de un paisaje más amplio gestionado por la coexistencia sustentable entre la naturaleza y las personas. Un nuevo paradigma para las áreas protegidas y conservadas reconoce que la coordinación nacional, los incentivos y el monitoreo deberían respaldar, y no debilitar, a las diferentes iniciativas de conservación llevadas por la población local. Sin embargo, la definición de un área conservada debe mantener un enfoque sólido sobre la biodiversidad para seguir siendo coherente con la base de evidencias de la cual derivaron originalmente las metas de porcentaje de protección.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Clima , Geografia
3.
Conserv Biol ; 35(1): 155-167, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32557877

RESUMO

Expansion of the global protected-area network has been proposed as a strategy to address threats from accelerating climate change and species extinction. A key step in increasing the effectiveness of such expansion is understanding how novel threats to biodiversity from climate change alter concepts such as rewilding, which have underpinned many proposals for large interconnected reserves. We reviewed potential challenges that climate change poses to rewilding and found that the conservation value of large protected areas persists under climate change. Nevertheless, more attention should be given to protection of microrefugia, macrorefugia, complete environmental gradients, and areas that connect current and future suitable climates and to maintaining ecosystem processes and stabilizing feedbacks via conservation strategies that are resilient to uncertainty regarding climate trends. Because a major element of the threat from climate change stems from its novel geographic patterns, we examined, as an example, the implications for climate-adaptation planning of latitudinal, longitudinal (continental to maritime), and elevational gradients in climate-change exposure across the Yellowstone-to-Yukon region, the locus of an iconic conservation proposal initially designed to conserve wide-ranging carnivore species. In addition to a continued emphasis on conserving intact landscapes, restoration of degraded low-elevation areas within the region is needed to capture sites important for landscape-level climate resilience. Extreme climate exposure projected for boreal North America suggests the need for ambitious goals for expansion of the protected-area network there to include refugia created by topography and ecological features, such as peatlands, whose conservation can also reduce emissions from carbon stored in soil. Qualitative understanding of underlying reserve design rules and the geography of climate-change exposure can strengthen the outcomes of inclusive regional planning processes that identify specific sites for protection.


Retorno a la Vida Silvestre de frente al Cambio Climático Resumen La expansión de la red mundial de áreas protegidas ha sido propuesta como una estrategia para tratar con las amenazas del creciente cambio climático y la extinción de especies. Un paso importante para el incremento de la efectividad de dicha expansión es el entendimiento de cómo las amenazas novedosas para la biodiversidad que provienen del cambio climático alteran conceptos como el retorno a la vida silvestre, el cual ha apuntalado muchas propuestas de grandes reservas interconectadas. Revisamos los obstáculos potenciales que representan el cambio climático para el retorno a la vida silvestre y encontramos que el valor de conservación de las áreas protegidas grandes persiste bajo el cambio climático. Sin embargo, se le debería brindar mayor atención a la protección de los microrefugios, del gradiente ambiental completo y de las áreas que conectan climas adecuados actuales y futuros. También se le debe brindar atención al mantenimiento de los procesos ambientales y a la estabilización de la retroalimentación por medio las estrategias de conservación que son resilientes a la incertidumbre relacionada con las tendencias climáticas. Ya que un elemento principal de la amenaza que representa el cambio climático surge de sus patrones geográficos novedosos examinamos, como ejemplo, las implicaciones de los gradientes latitudinales, longitudinales (continental a marítima) y altitudinales para la planeación de la adaptación climática dentro de la exposición al cambio climático en toda la región de Yellowstone a Yukón, el sitio de una propuesta icónica de conservación diseñada inicialmente para conservar especies carnívoras de amplia distribución. Además de un énfasis continuo sobre la conservación intacta del paisaje, se requiere la restauración de las áreas degradadas de baja elevación dentro de la región para capturar los sitios importantes para la resiliencia climática a nivel de paisaje. La exposición climática extrema proyectada para la parte boreal de América del Norte sugiere que se necesitan metas ambiciosas para la expansión de la red de áreas protegidas que se encuentran allí para incluir también a los refugios creados por la topografía y las características ecológicas, como las turberas, cuya conservación también puede reducir las emisiones de carbono almacenado en el suelo. El entendimiento cualitativo de las reglas subyacentes de diseño de reservas y la geografía de la exposición al cambio climático puede fortalecer los resultados de los procesos de planeación regional incluyente para identificar los sitios específicos que requieren protección.


Assuntos
Mudança Climática , Ecossistema , Biodiversidade , Conservação dos Recursos Naturais , América do Norte
4.
Conserv Biol ; 35(6): 1715-1724, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34057264

RESUMO

Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and Wildlife Service (USFWS) to streamline ESA decisions include multispecies recovery plans and habitat conservation plans. We address species status assessment (SSA), a USFWS process to inform ESA decisions from listing to recovery, within the context of multispecies and ecosystem planning. Although existing SSAs have a single-species focus, ecosystem-based research can efficiently inform multiple SSAs within a region and provide a foundation for transition to multispecies SSAs in the future. We considered at-risk grassland species and ecosystems within the southeastern United States, where a disproportionate number of rare and endemic species are associated with grasslands. To initiate our ecosystem-based approach, we used a combined literature-based and structured World Café workshop format to identify science needs for SSAs. Discussions concentrated on 5 categories of threats to grassland species and ecosystems, consistent with recommendations to make shared threats a focus of planning under the ESA: (1) habitat loss, fragmentation, and disruption of functional connectivity; (2) climate change; (3) altered disturbance regimes; (4) invasive species; and (5) localized impacts. For each threat, workshop participants identified science and information needs, including database availability, research priorities, and modeling and mapping needs. Grouping species by habitat and shared threats can make the SSA process and other planning processes for conservation of at-risk species worldwide more efficient and useful. We found a combination of literature review and structured discussion effective for identifying the scientific information and analysis needed to support the development of multiple SSAs. Article impact statement: Species status assessments can be improved by an ecosystem-based approach that groups imperiled species by shared habitats and threats.


Mejoramiento de la Evaluación del Estado de una Especie bajo el Acta de Especies en Peligro de los Estados Unidos y Sus Consecuencias para los Retos de la Conservación Multiespecie a Nivel Mundial Resumen A pesar de su éxito, el Acta de Especies en Peligro de los E.U.A. (AEP) ha sido un reto de implementación por las limitaciones en su financiamiento, el retraso en la carga de trabajo y otros problemas. Conforme se intensifican las amenazas a la supervivencia de las especies y más especies resultan amenazadas, aumenta la necesidad de que la AEP y las políticas similares de otros países funcionen efectivamente. Los intentos por parte del Servicio Estadounidense de Pesca y Fauna (SEPF) para optimizar las decisiones de la AEP incluyen planes multiespecie de recuperación y planes de conservación de hábitat (PRH). Abordamos la evaluación del estado de las especies (EEE), un proceso del SEPF para orientar las decisiones del AEP desde el listado hasta la recuperación, dentro del contexto de la planeación multiespecie y de ecosistemas. Aunque las EEE existentes tienen un enfoque sobre una única especie, la investigación basada en el ecosistema puede orientar eficientemente a múltiples EEE dentro de una región y proporcionar una base para la transición a las EEE multiespecie en el futuro. Consideramos a las especies y los ecosistemas en riesgo de los pastizales del sureste de los Estados Unidos, en donde un número desproporcionado de especies raras y endémicas está asociado con los pastizales. Para iniciar nuestra estrategia basada en el ecosistema, usamos un formato de taller de World Café estructurado y basado en la literatura para identificar la necesidad de tener EEE. Las discusiones se centraron en cinco categorías de amenazas para las especies y ecosistemas de los pastizales, consistentes con las recomendaciones para volver a las amenazas compartidas un foco de la planeación bajo la AEP: (1) pérdida del hábitat, fragmentación y disrupción de la conectividad funcional; (2) cambio climático; (3) regímenes alterados de perturbación; (4) especies invasoras; y (5) impactos localizados. Para cada amenaza, los participantes del taller identificaron las necesidades científicas y de información, incluyendo la disponibilidad de bases de datos, prioridades de la investigación y necesidades de modelado y mapeado. La agrupación de las especies por hábitat y amenaza compartida puede hacer más eficientes y útiles el proceso de EEE y otros procesos de planeación de la conservación de especies en riesgo a nivel mundial. Encontramos una combinación de revisiones bibliográficas y discusiones estructuradas para identificar la información y el análisis necesarios para respaldar el desarrollo de múltiples EEE.


Assuntos
Ecossistema , Espécies em Perigo de Extinção , Animais , Mudança Climática , Conservação dos Recursos Naturais , Humanos , Espécies Introduzidas
5.
Conserv Biol ; 35(1): 360-368, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32860266

RESUMO

Extinction rates are expected to increase during the Anthropocene. Current extinction rates of plants and many animals remain unknown. We quantified extinctions among the vascular flora of the continental United States and Canada since European settlement. We compiled data on apparently extinct species by querying plant conservation databases, searching the literature, and vetting the resulting list with botanical experts. Because taxonomic opinion varies widely, we developed an index of taxonomic uncertainty (ITU). The ITU ranges from A to F, with A indicating unanimous taxonomic recognition and F indicating taxonomic recognition by only a single author. The ITU allowed us to rigorously evaluate extinction rates. Our data suggest that 51 species and 14 infraspecific taxa, representing 33 families and 49 genera of vascular plants, have become extinct in our study area since European settlement. Seven of these taxa exist in cultivation but are extinct in the wild. Most extinctions occurred in the west, but this outcome may reflect the timing of botanical exploration relative to settlement. Sixty-four percent of extinct plants were single-site endemics, and many occurred outside recognized biodiversity hotspots. Given the paucity of plant surveys in many areas, particularly prior to European settlement, the actual extinction rate of vascular plants is undoubtedly much higher than indicated here.


Extinción de las Plantas Vasculares en Canadá y los Estados Unidos Continentales Resumen Se espera que las tasas de extinción aumenten durante el Antropoceno. Todavía desconocemos las tasas de extinción actuales de las plantas y muchos animales. Cuantificamos las tasas de extinción de la flora vascular de los Estados Unidos Continentales y Canadá a partir del asentamiento de los europeos. Recopilamos datos sobre especies aparentemente extintas mediante la consulta de bases de datos sobre conservación, búsquedas en la literatura y el escrutinio de la lista resultante con botánicos expertos. Ya que la opinión taxonómica varía ampliamente, desarrollamos un índice de incertidumbre taxonómica (ITU). La ITU abarca desde la A hasta la F, en donde la A indica un reconocimiento taxonómico unánime y la F indica el reconocimiento taxonómico por un sólo autor. La ITU nos permitió evaluar rigurosamente las tasas de extinción. Nuestros datos sugieren que 51 especies y 14 taxones infraespecíficos, que en conjunto representan a 33 familias y a 49 géneros de plantas vasculares, se han extinguido en nuestra área de estudio desde el asentamiento de los europeos. Siete de estos taxones existen en cultivos, pero se encuentran extintos en vida libre. La mayoría de las extinciones ocurrieron en la parte oeste del área de estudio, aunque este resultado puede reflejar el momento de la exploración botánica en relación con el asentamiento europeo. El 64% de las plantas extintas eran endémicas de un sitio único y muchas tuvieron presencia fuera de los puntos calientes de biodiversidad. Dada la escasez de los censos botánicos en muchas áreas, particularmente previo al asentamiento europeo, la tasa actual de extinción de las plantas vasculares es sin duda mucho más alta de lo que se indica en este estudio.


Assuntos
Conservação dos Recursos Naturais , Extinção Biológica , Animais , Biodiversidade , Canadá , Plantas , Estados Unidos
6.
Conserv Biol ; 35(6): 1882-1893, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33728690

RESUMO

There has been much recent interest in the concept of rewilding as a tool for nature conservation, but also confusion over the idea, which has limited its utility. We developed a unifying definition and 10 guiding principles for rewilding through a survey of 59 rewilding experts, a summary of key organizations' rewilding visions, and workshops involving over 100 participants from around the world. The guiding principles convey that rewilding exits on a continuum of scale, connectivity, and level of human influence and aims to restore ecosystem structure and functions to achieve a self-sustaining autonomous nature. These principles clarify the concept of rewilding and improve its effectiveness as a tool to achieve global conservation targets, including those of the UN Decade on Ecosystem Restoration and post-2020 Global Biodiversity Framework. Finally, we suggest differences in rewilding perspectives lie largely in the extent to which it is seen as achievable and in specific interventions. An understanding of the context of rewilding projects is the key to success, and careful site-specific interpretations will help achieve the aims of rewilding.


Recientemente ha habido mucho interés por el concepto de retorno a la vida silvestre como herramienta para la conservación de la naturaleza, pero también ha habido confusión por la idea que ha limitado su utilidad. Desarrollamos una definición unificadora y diez principios básicos para el retorno a la vida silvestre por medio de encuestas a 59 expertos en retorno a la vida silvestre, un resumen de las visiones de las organizaciones más importantes para el retorno a la vida silvestre y talleres que involucraron a más de 100 participantes de todo el mundo. Los principios básicos transmiten que el retorno a la vida silvestre existe en un continuo de escala, conectividad y nivel de influencia humana y que su objetivo es restaurar la estructura y las funciones del ecosistema para lograr una naturaleza autónoma autosustentable. Estos principios aclaran el concepto del retorno a la vida silvestre e incrementan su efectividad como herramienta para lograr los objetivos mundiales de conservación, incluyendo aquellos de la Década de la ONU para la Restauración de Ecosistemas y el Marco de Trabajo de la Biodiversidad Global post 2020. Finalmente, sugerimos que las diferencias en las perspectivas del retorno a la vida silvestre yacen principalmente en el grado al que es visto como factible y en intervenciones específicas. Un entendimiento del contexto de los proyectos de retorno a la vida silvestre es importante para el éxito, y las interpretaciones específicas de sitio ayudarán a lograr las metas del retorno a la vida silvestre. Principios Básicos para el Retorno a la Vida Silvestre.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Humanos
7.
Conserv Biol ; 32(2): 315-321, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28722213

RESUMO

The establishment of protected areas is a critical strategy for conserving biodiversity. Key policy directives like the Aichi targets seek to expand protected areas to 17% of Earth's land surface, with calls by some conservation biologists for much more. However, in places such as the United States, Germany, and Australia, attempts to increase protected areas are meeting strong resistance from communities, industry groups, and governments. We examined case studies of such resistance in Victoria, Australia, Bavaria, Germany, and Florida, United States. We considered 4 ways to tackle this problem. First, broaden the case for protected areas beyond nature conservation to include economic, human health, and other benefits, and translate these into a persuasive business case for protected areas. Second, better communicate the conservation values of protected areas. This should include highlighting how many species, communities, and ecosystems have been conserved by protected areas and the counterfactual (i.e., what would have been lost without protected area establishment). Third, consider zoning of activities to ensure the maintenance of effective management. Finally, remind citizens to think about conservation when they vote, including holding politicians accountable for their environmental promises. Without tackling resistance to expanding the protected estate, it will be impossible to reach conservation targets, and this will undermine attempts to stem the global extinction crisis.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Florida , Alemanha , Humanos , Vitória
8.
Bioscience ; 67(6): 534-545, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28608869

RESUMO

We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature-a companion to the Paris Climate Deal-to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Clima , Ecologia , Ecossistema , Humanos
9.
Ann Bot ; 119(2): 207-214, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28064195

RESUMO

BACKGROUND: Centres of endemism have received much attention from evolutionists, biogeographers, ecologists and conservationists. Climatic stability is often cited as a major reason for the occurrences of these geographic concentrations of species which are not found anywhere else. The proposed linkage between endemism and climatic stability raises unanswered questions about the persistence of biodiversity during the present era of rapidly changing climate. KEY QUESTIONS: The current status of evidence linking geographic centres of endemism to climatic stability over evolutionary time was examined. The following questions were asked. Do macroecological analyses support such an endemism-stability linkage? Do comparative studies find that endemic species display traits reflecting evolution in stable climates? Will centres of endemism in microrefugia or macrorefugia remain relatively stable and capable of supporting high biological diversity into the future? What are the implications of the endemism-stability linkage for conservation? CONCLUSIONS: Recent work using the concept of climate change velocity supports the classic idea that centres of endemism occur where past climatic fluctuations have been mild and where mountainous topography or favourable ocean currents contribute to creating refugia. Our knowledge of trait differences between narrow endemics and more widely distributed species remains highly incomplete. Current knowledge suggests that centres of endemism will remain relatively climatically buffered in the future, with the important caveat that absolute levels of climatic change and species losses in these regions may still be large.


Assuntos
Mudança Climática , Biodiversidade , Evolução Biológica , Plantas
10.
Conserv Biol ; 28(1): 4-12, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24400726

RESUMO

Public agencies sometimes seek outside guidance when capacity to achieve their mission is limited. Through a cooperative agreement and collaborations with the U.S. National Park Service (NPS), we developed recommendations for a conservation program for migratory species. Although NPS manages ∼ 36 million hectares of land and water in 401 units, there is no centralized program to conserve wild animals reliant on NPS units that also migrate hundreds to thousands of kilometers beyond parks. Migrations are imperiled by habitat destruction, unsustainable harvest, climate change, and other impediments. A successful program to counter these challenges requires public support, national and international outreach, and flourishing migrant populations. We recommended two initial steps. First, in the short term, launch or build on a suite of projects for high-profile migratory species that can serve as proof to demonstrate the centrality of NPS units to conservation at different scales. Second, over the longer term, build new capacity to conserve migratory species. Capacity building will entail increasing the limited knowledge among park staff about how and where species or populations migrate, conditions that enable migration, and identifying species' needs and resolving them both within and beyond parks. Building capacity will also require ensuring that park superintendents and staff at all levels support conservation beyond statutory borders. Until additional diverse stakeholders and a broader American public realize what can be lost and do more to protect it and engage more with land management agencies to implement actions that facilitate conservation, long distance migrations are increasingly likely to become phenomena of the past.


Assuntos
Migração Animal , Biodiversidade , Conservação dos Recursos Naturais , Política Ambiental , Animais , Estados Unidos
13.
Conserv Biol ; 24(5): 1367-77, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20455907

RESUMO

Biodiversity is too complex to measure directly, so conservation planning must rely on surrogates to estimate the biodiversity of sites. The species richness of selected taxa is often used as a surrogate for the richness of other taxa. Surrogacy values of taxa have been evaluated in diverse contexts, yet broad trends in their effectiveness remain unclear. We reviewed published studies testing the ability of species richness of surrogate taxa to capture the richness of other (target) taxa. We stratified studies into two groups based on whether a complementarity approach (surrogates used to select a combination of sites that together maximize total species richness for the taxon) or a richness-hotspot approach (surrogates used to select sites containing the highest species richness for the taxon) was used. For each comparison of one surrogate taxon with one target, we used the following predictor variables: biome, spatial extent of study area, surrogate taxon, and target taxon. We developed a binary response variable based on whether the surrogate taxon provided better than random representation of the target taxon. For studies that used an evaluation approach that was not based on better than random representation of target taxa, we based the response variable on the interpretation of results in the original study. We performed a categorical regression to elucidate trends in the effectiveness of surrogate taxa with regard to each of the predictor variables. A surrogate was 25% more likely to be effective with a complementarity approach than with a hotspot approach. For hotspot-based approaches, biome, extent of study, surrogate taxon, and target taxon significantly influenced effectiveness of the surrogate. For complementarity-based approaches, biome, extent, and surrogate taxon significantly influenced effectiveness of the surrogate. For all surrogate evaluations, biome explained the greatest amount of variation in surrogate effectiveness. From most to least, extent, surrogate taxon, and target taxon explained the most variation after biome. Surrogate taxa were most effective in grasslands and in some cases boreal zones, deserts, and tropical forests; surrogate taxa also were more effective in studies examining larger areas. Herpetofauna were the most effective taxon as both surrogate and target when a richness-hotspot approach was used; however, herpetofauna were analyzed in fewer studies, so this result is tentative. For complementarity approaches, taxa that are easy to measure and tend to have a large number of habitat specialists distributed collectively across broad environmental gradients (e.g., plants, birds, and mammals) were the most effective surrogates.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Ecossistema , Modelos Biológicos , Demografia , Análise de Regressão , Especificidade da Espécie
15.
Conserv Biol ; 23(4): 825-33, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19627314

RESUMO

The Society for Conservation Biology (SCB) can enhance conservation of biodiversity in North America by increasing its engagement in public policy. Toward this end, the North America Section of SCB is establishing partnerships with other professional organizations in order to speak more powerfully to decision makers and taking other actions--such as increasing interaction with chapters--geared to engage members more substantively in science-policy issues. Additionally, the section is developing a North American Biodiversity Blueprint, which spans the continental United States and Canada and is informed by natural and social science. This blueprint is intended to clarify the policy challenges for protecting continental biodiversity, to foster bilateral collaboration to resolve common problems, and to suggest rational alternative policies and practices that are more likely than current practices to sustain North America's natural heritage. Conservation scientists and practitioners can play a key role by drawing policy makers' attention to ultimate, as well as proximate, causes of biodiversity decline and to the ecological and economic consequences of not addressing these threats.


Assuntos
Conservação dos Recursos Naturais , Meio Ambiente , Biodiversidade , Canadá , Ecossistema , Estados Unidos
16.
PLoS One ; 14(9): e0221705, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31509559

RESUMO

Agricultural development was the major contributor to South America's designation as the continent with the highest rates of forest loss from 2000-2012. As the apex predator in the Neotropics, jaguars (Panthera onca) are dependent on forest cover but the species' response to habitat fragmentation in heterogeneous agricultural landscapes has not been a subject of extensive research. We used occupancy as a measure of jaguar habitat use in Colombia's middle Magdalena River valley which, as part of the intercontinental Tumbes-Chocó-Magdalena biodiversity hotspot, is exceedingly fragmented by expanding cattle pastures and oil palm plantations. We used single-season occupancy models to analyze 9 months of data (2015-2016) from 70 camera trap sites. Given the middle Magdalena's status as a "jaguar corridor" and our possible violation of the occupancy models' demographic closure assumption, we interpreted our results as "probability of habitat use (Ψ)" by jaguars. We measured the associations between jaguar presence and coverage of forest, oil palm, and wetlands in radii buffers of 1, 3, and 5 km around each camera trap. Our camera traps recorded 77 jaguar detections at 25 of the camera trap sites (36%) during 15,305 trap nights. The probability of detecting jaguars, given their presence at a site, was 0.28 (0.03 SE). In the top-ranked model, jaguar habitat use was positively influenced by wetland coverage (ß = 7.16, 3.20 SE) and negatively influenced by cattle pastures (ß = -1.40, 0.63 SE), both in the 3 km buffers. We conclude that wetlands may serve as keystone habitats for jaguars in landscapes fragmented by cattle ranches and oil palm plantations. Greater focus on wetland preservation could facilitate jaguar persistence in one of the most important yet vulnerable areas of their distribution.


Assuntos
Conservação dos Recursos Naturais/métodos , Panthera/fisiologia , Animais , Biodiversidade , Colômbia , Ecossistema , Feminino , Masculino , Densidade Demográfica , Gravação em Vídeo , Áreas Alagadas
17.
Science ; 366(6463)2019 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-31624182

RESUMO

Bastin et al's estimate (Reports, 5 July 2019, p. 76) that tree planting for climate change mitigation could sequester 205 gigatonnes of carbon is approximately five times too large. Their analysis inflated soil organic carbon gains, failed to safeguard against warming from trees at high latitudes and elevations, and considered afforestation of savannas, grasslands, and shrublands to be restoration.


Assuntos
Solo , Árvores , Carbono , Sequestro de Carbono , Mudança Climática
18.
Ecol Lett ; 11(1): 78-91, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17927771

RESUMO

The management of landscapes for biological conservation and ecologically sustainable natural resource use are crucial global issues. Research for over two decades has resulted in a large literature, yet there is little consensus on the applicability or even the existence of general principles or broad considerations that could guide landscape conservation. We assess six major themes in the ecology and conservation of landscapes. We identify 13 important issues that need to be considered in developing approaches to landscape conservation. They include recognizing the importance of landscape mosaics (including the integration of terrestrial and aquatic areas), recognizing interactions between vegetation cover and vegetation configuration, using an appropriate landscape conceptual model, maintaining the capacity to recover from disturbance and managing landscapes in an adaptive framework. These considerations are influenced by landscape context, species assemblages and management goals and do not translate directly into on-the-ground management guidelines but they should be recognized by researchers and resource managers when developing guidelines for specific cases. Two crucial overarching issues are: (i) a clearly articulated vision for landscape conservation and (ii) quantifiable objectives that offer unambiguous signposts for measuring progress.


Assuntos
Conservação dos Recursos Naturais/métodos , Meio Ambiente , Ecossistema , Modelos Biológicos
20.
Accid Anal Prev ; 109: 55-61, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29031047

RESUMO

Roadside Animal Detection Systems (RADS) aim to reduce the frequency of wildlife-vehicle collisions. Unlike fencing and wildlife passages, RADS do not attempt to keep animals off the road; rather, they attempt to modify driver behavior by detecting animals near the road and warning drivers with flashing signs. A RADS was installed in Big Cypress National Park (Florida, USA) in 2012 in response to an increased number of Florida panther mortalities. To assess driver response, we measured the speed of individual cars on the road when the RADS was active (flashing) and inactive (not flashing) during the tourist season (November-March) and the off-season (April-October), which vary dramatically in traffic volume. We also used track beds and camera traps to assess whether roadside activity of large mammal species varied between seasons. In the tourist season, the activation of the RADS caused a significant reduction in vehicle speed. However, this effect was not observed in the off-season. Track and camera data showed that the tourist season coincided with peak periods of activity for several large mammals of conservation interest. Drivers in the tourist season generally drove faster than those in the off-season, so a reduction in speed in response to the RADS is more beneficial in the tourist season. Because traffic volume and roadside activity of several species of conservation interest both peak during the tourist season, our study indicates that the RADS has the potential to reduce the number of accidents during this period of heightened risk.


Assuntos
Acidentes de Trânsito/prevenção & controle , Bem-Estar do Animal , Condução de Veículo , Automóveis , Acidentes de Trânsito/estatística & dados numéricos , Animais , Coiotes , Cervos , Florida , Humanos , Lynx , Risco , Estações do Ano , Ursidae
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA