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1.
Conserv Biol ; 36(5): e13960, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35661264

RESUMO

To combat biodiversity loss, there is increasing interest in safeguarding habitat by expanding protected areas. Given limited resources in conservation, organizations must invest in places that will add the greatest amount of value in species protection. To determine the added conservation value of protection, one needs to consider the level of human disturbance in areas that would result if they were left unprotected. In recent years, data resources have become available that reveal the spatial heterogeneity in human disturbance over large spatial extents worldwide. We investigated how accounting for heterogeneity in future disturbance in unprotected areas affects prioritization of protected areas by determining the added value offered by protection of different areas. We applied a complementarity-based framework for protected area prioritization to select protected areas in the coterminous United States under different assumptions about the heterogeneity of future disturbance in unprotected areas. Prioritizing protected areas while incorrectly assuming spatially homogeneous disturbance in unprotected areas, a common assumption, led to a loss of 76% of possible conservation gain for a given budget. The conservation return on investment from protecting candidate areas was positively correlated (0.44) to future human disturbance in that area if it was left unprotected. Our results show that the ability to identify cost-effective protected area networks depends on how one accounts for the ecological contribution of private lands that remain unprotected.


Existe un creciente interés por salvaguardar los hábitats mediante la expansión de áreas protegidas para combatir la pérdida de la biodiversidad. Debido a los recursos limitados para la conservación, las organizaciones deben invertir en localidades que adicionarán la mayor cantidad de valor a la protección de las especies. Para determinar el valor de conservación adicionado por la protección se necesita considerar el nivel de perturbación humana en las áreas que ocurriría si se les dejara desprotegidas. En años recientes, han quedado disponibles recursos informativos que revelan la heterogeneidad espacial en la perturbación humana a lo largo de grandes extensiones espaciales a nivel mundial. Investigamos cómo considerar esta heterogeneidad en las futuras perturbaciones de las áreas desprotegidas afecta la priorización de las áreas protegidas mediante la determinación del valor adicionado que ofrece la protección de diferentes áreas. Aplicamos un marco de trabajo basado en la complementariedad para la priorización de áreas protegidas para seleccionar estas áreas en los estados colindantes de los Estados Unidos bajo diferentes suposiciones sobre la heterogeneidad de las perturbaciones futuras en las áreas desprotegidas. La priorización de las áreas protegidas mientras se asumía incorrectamente la perturbación espacial homogénea en las áreas desprotegidas, una suposición común, resultó en una pérdida del 76% de la posible ganancia de conservación para un presupuesto dado. El rendimiento de la conservación en la inversión a partir de la protección de las áreas candidatas estuvo correlacionado positivamente (0.44) con las perturbaciones humanas en el futuro si el área permanece desprotegida. Nuestros resultados muestran que la capacidad de identificar las redes rentables de áreas protegidas depende de cómo se consideran las contribuciones ecológicas de las tierras privadas que permanecen desprotegidas.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Humanos , Estados Unidos
2.
Biol Conserv ; 257: 109078, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34584274

RESUMO

Emerging zoonotic diseases, such as COVID-19, exist at the intersection of human health and the environment. Public interest and support are required to maximize the effectiveness of policies to combat the current pandemic and prevent future outbreaks of zoonoses. Here, we use internet search data from the United States to investigate changes in public information seeking about topics at the intersection of health and the environment during the COVID-19 pandemic. Using breakpoint detection methods, we identify sharp increases in interest for 'wildlife trade', 'bats', and 'pangolins' in the early stages of the pandemic (on Jan. 12, Jan. 19, and Jan. 26, 2020, respectively). Network analyses also revealed increasing connectivity between terms related to human health and the environment, as well as the emergence of novel search terms pointing to a greater interest in wildlife trade and consumption. During the pandemic, the network connectivity between coronavirus keywords and conservation keywords increased, which we measured using the number of unique connections (edge connectivity, k' (G)) and the number of simple paths (Sp) between keywords. Both measures of network connectivity increased between 'coronavirus' and 'bats' or 'pangolins' (Δk' (G) = 1, ΔSp = 37), and between 'coronavirus' and 'conservation' (Δk' (G) = 1, ΔSp = 160). These findings suggest that policy and outreach efforts aimed at engaging public interest in intersectional approaches to pandemic prevention (eg: One Health, Planetary Health), may be able to take advantage of increases in public information seeking following catalyzing events during the pandemic. Further monitoring is needed to determine if these changes persist over time.

3.
Proc Natl Acad Sci U S A ; 118(4)2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33468666

RESUMO

Global cropland expansion over the last century caused widespread habitat loss and degradation. Establishment of protected areas aims to counteract the loss of habitats and to slow species extinctions. However, many protected areas also include high levels of habitat disturbance and conversion for uses such as cropland. Understanding where and why this occurs may realign conservation priorities and inform protected area policy in light of competing priorities such as food security. Here, we use our global synthesis cropland dataset to quantify cropland in protected areas globally and assess their relationship to conservation aims and socio-environmental context. We estimate that cropland occupies 1.4 million km2 or 6% of global protected area. Cropland occurs across all protected area management types, with 22% occurring in strictly protected areas. Cropland inside protected areas is more prevalent in countries with higher population density, lower income inequality, and with higher agricultural suitability of protected lands. While this phenomenon is dominant in midnorthern latitudes, areas of cropland in protected areas of the tropics and subtropics may present greater trade-offs due to higher levels of both biodiversity and food insecurity. Although area-based targets are prominent in biodiversity goal-setting, our results show that they can mask persistent anthropogenic land uses detrimental to native ecosystem conservation. To ensure the long-term efficacy of protected areas, post-2020 goal setting must link aims for biodiversity and human health and improve monitoring of conservation outcomes in cropland-impacted protected areas.


Assuntos
Agricultura/tendências , Conservação dos Recursos Naturais , Ecossistema , Segurança Alimentar , Biodiversidade , Produtos Agrícolas/crescimento & desenvolvimento , Extinção Biológica , Florestas , Humanos , Densidade Demográfica
4.
PeerJ ; 5: e4096, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29250465

RESUMO

Assessing the numbers and distribution of threatened species is a central challenge in conservation, often made difficult because the species of concern are rare and elusive. For some predators, this may be compounded by their being sparsely distributed over large areas. Such is the case with the cheetah Acinonyx jubatus. The IUCN Red List process solicits comments, is democratic, transparent, widely-used, and has recently assessed the species. Here, we present additional methods to that process and provide quantitative approaches that may afford greater detail and a benchmark against which to compare future assessments. The cheetah poses challenges, but also affords unique opportunities. It is photogenic, allowing the compilation of thousands of crowd-sourced data. It is also persecuted for killing livestock, enabling estimation of local population densities from the numbers persecuted. Documented instances of persecution in areas with known human and livestock density mean that these data can provide an estimate of where the species may or may not occur in areas without observational data. Compilations of extensive telemetry data coupled with nearly 20,000 additional observations from 39 sources show that free-ranging cheetahs were present across approximately 789,700 km2 of Namibia, Botswana, South Africa, and Zimbabwe (56%, 22%, 12% and 10% respectively) from 2010 to 2016, with an estimated adult population of 3,577 animals. We identified a further 742,800 km2 of potential cheetah habitat within the study region with low human and livestock densities, where another ∼3,250 cheetahs may occur. Unlike many previous estimates, we make the data available and provide explicit information on exactly where cheetahs occur, or are unlikely to occur. We stress the value of gathering data from public sources though these data were mostly from well-visited protected areas. There is a contiguous, transboundary population of cheetah in southern Africa, known to be the largest in the world. We suggest that this population is more threatened than believed due to the concentration of about 55% of free-ranging individuals in two ecoregions. This area overlaps with commercial farmland with high persecution risk; adult cheetahs were removed at the rate of 0.3 individuals per 100 km2 per year. Our population estimate for confirmed cheetah presence areas is 11% lower than the IUCN's current assessment for the same region, lending additional support to the recent call for the up-listing of this species from vulnerable to endangered status.

5.
PLoS One ; 11(7): e0159668, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27462984

RESUMO

Palm oil is the most widely traded vegetable oil globally, with demand projected to increase substantially in the future. Almost all oil palm grows in areas that were once tropical moist forests, some of them quite recently. The conversion to date, and future expansion, threatens biodiversity and increases greenhouse gas emissions. Today, consumer pressure is pushing companies toward deforestation-free sources of palm oil. To guide interventions aimed at reducing tropical deforestation due to oil palm, we analysed recent expansions and modelled likely future ones. We assessed sample areas to find where oil palm plantations have recently replaced forests in 20 countries, using a combination of high-resolution imagery from Google Earth and Landsat. We then compared these trends to countrywide trends in FAO data for oil palm planted area. Finally, we assessed which forests have high agricultural suitability for future oil palm development, which we refer to as vulnerable forests, and identified critical areas for biodiversity that oil palm expansion threatens. Our analysis reveals regional trends in deforestation associated with oil palm agriculture. In Southeast Asia, 45% of sampled oil palm plantations came from areas that were forests in 1989. For South America, the percentage was 31%. By contrast, in Mesoamerica and Africa, we observed only 2% and 7% of oil palm plantations coming from areas that were forest in 1989. The largest areas of vulnerable forest are in Africa and South America. Vulnerable forests in all four regions of production contain globally high concentrations of mammal and bird species at risk of extinction. However, priority areas for biodiversity conservation differ based on taxa and criteria used. Government regulation and voluntary market interventions can help incentivize the expansion of oil palm plantations in ways that protect biodiversity-rich ecosystems.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Produção Agrícola , Óleos de Plantas/economia , África , Animais , Espécies em Perigo de Extinção , Florestas , Óleo de Palmeira , América do Sul
6.
Sci Adv ; 2(11): e1601367, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28861465

RESUMO

The IUCN (International Union for Conservation of Nature) Red List classifies species according to their risk of extinction, informing global to local conservation decisions. Unfortunately, important geospatial data do not explicitly or efficiently enter this process. Rapid growth in the availability of remotely sensed observations provides fine-scale data on elevation and increasingly sophisticated characterizations of land cover and its changes. These data readily show that species are likely not present within many areas within the overall envelopes of their distributions. Additionally, global databases on protected areas inform how extensively ranges are protected. We selected 586 endemic and threatened forest bird species from six of the world's most biodiverse and threatened places (Atlantic Forest of Brazil, Central America, Western Andes of Colombia, Madagascar, Sumatra, and Southeast Asia). The Red List deems 18% of these species to be threatened (15 critically endangered, 29 endangered, and 64 vulnerable). Inevitably, after refining ranges by elevation and forest cover, ranges shrink. Do they do so consistently? For example, refined ranges of critically endangered species might reduce by (say) 50% but so might the ranges of endangered, vulnerable, and nonthreatened species. Critically, this is not the case. We find that 43% of species fall below the range threshold where comparable species are deemed threatened. Some 210 bird species belong in a higher-threat category than the current Red List placement, including 189 species that are currently deemed nonthreatened. Incorporating readily available spatial data substantially increases the numbers of species that should be considered at risk and alters priority areas for conservation.


Assuntos
Aves , Bases de Dados Factuais , Espécies em Perigo de Extinção , Extinção Biológica , Florestas , Animais
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