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1.
Nature ; 610(7932): 513-518, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36224387

RESUMO

As the United Nations develops a post-2020 global biodiversity framework for the Convention on Biological Diversity, attention is focusing on how new goals and targets for ecosystem conservation might serve its vision of 'living in harmony with nature'1,2. Advancing dual imperatives to conserve biodiversity and sustain ecosystem services requires reliable and resilient generalizations and predictions about ecosystem responses to environmental change and management3. Ecosystems vary in their biota4, service provision5 and relative exposure to risks6, yet there is no globally consistent classification of ecosystems that reflects functional responses to change and management. This hampers progress on developing conservation targets and sustainability goals. Here we present the International Union for Conservation of Nature (IUCN) Global Ecosystem Typology, a conceptually robust, scalable, spatially explicit approach for generalizations and predictions about functions, biota, risks and management remedies across the entire biosphere. The outcome of a major cross-disciplinary collaboration, this novel framework places all of Earth's ecosystems into a unifying theoretical context to guide the transformation of ecosystem policy and management from global to local scales. This new information infrastructure will support knowledge transfer for ecosystem-specific management and restoration, globally standardized ecosystem risk assessments, natural capital accounting and progress on the post-2020 global biodiversity framework.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Política Ambiental , Biodiversidade , Biota , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Política Ambiental/legislação & jurisprudência , Política Ambiental/tendências , Objetivos , Nações Unidas , Animais
2.
Sci Total Environ ; 820: 152892, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35051468

RESUMO

Oil and gas extraction activities occur across the globe, yet species-specific toxicological information on the biological and ecological impacts of exposure to petrochemicals is lacking for the vast majority of marine species. To help prioritize species for recovery, mitigation, and conservation in light of significant toxicological data gaps, a trait-based petrochemical vulnerability index was developed and applied to the more than 1700 marine fishes present across the entire Gulf of Mexico, including all known bony fishes, sharks, rays and chimaeras. Using life history and other traits related to likelihood of exposure, physiological sensitivity to exposure, and population resiliency, final calculated petrochemical vulnerability scores can be used to provide information on the relative sensitivity, or resilience, of marine fish populations across the Gulf of Mexico to oil and gas activities. Based on current knowledge of traits, marine fishes with the highest vulnerability scores primarily occur in areas of high petrochemical activity, are found at or near the surface, and have low reproductive turnover rates and/or highly specialized diet and habitat requirements. Relative population vulnerability scores for marine fishes can be improved with additional toxicokinetic studies, including those that account for the synergistic or additive effect of multiple stressors, as well as increased research on ecological and life history traits, especially for deep living species.


Assuntos
Ecossistema , Peixes , Poluição por Petróleo , Poluentes Químicos da Água , Animais , Peixes/fisiologia , Golfo do México , México , Indústria de Petróleo e Gás , Reprodução , Especificidade da Espécie
3.
Mar Pollut Bull ; 116(1-2): 501-507, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28063697

RESUMO

The island nations and territories of the South Pacific are facing a number of pressing environmental concerns, including solid waste management and coastal pollution. Here we provide baseline information on the presence and concentration of heavy metals and selected organic contaminants (pesticides, PAHs, phthalates) in 7 coastal streams and in surface waters adjacent to the Futiga landfill in American Samoa. All sampled stream sediments contained high concentrations of lead, and some of mercury. Several coastal stream waters showed relatively high concentrations of diethyl phthalate and of organophosphate pesticides, above chronic toxicity values for fish and other aquatic organisms. Parathion, which has been banned by the US Environmental Protection Agency since 2006, was detected in several stream sites. Increased monitoring and initiatives to limit non-point source land-based pollution will greatly improve the state of freshwater and coastal resources, as well as reduce risks to human health in American Samoa.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Rios , Poluentes Químicos da Água/análise , Samoa Americana , Metais Pesados/análise , Praguicidas/análise , Ácidos Ftálicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
4.
Environ Sci Pollut Res Int ; 23(6): 5983-91, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26832877

RESUMO

Along the southeastern coast of Costa Rica, a variety of pesticides are intensively applied to produce export-quality plantains and bananas. In this region, and in other agricultural areas, fish kills are often documented by local residents and/or in the national news. This study examines principal exposure pathways, measured environmental concentrations, and selected toxicity thresholds of the three most prevalent pesticides (chlorpyrifos, terbufos, and difenoconazole) to construct a deterministic risk assessment for fish mortality. Comparisons of observed pesticide concentrations, along with estimated biological effects and observations during actual fish kills, highlight gaps in knowledge in correlating pesticide environmental concentration and toxicity in tropical environments. Observations of fish kill events and measured pesticide concentrations in the field, along with other water quality indicators, suggest that a number of environmental conditions can interact to cause fish mortality and that current species toxicity datasets may not be applicable for estimating toxicological or other synergistic effects, especially in tropical environments.


Assuntos
Peixes , Praguicidas/toxicidade , Agricultura , Animais , Clorpirifos/toxicidade , Costa Rica , Dioxolanos/toxicidade , Compostos Organotiofosforados/toxicidade , Praguicidas/análise , Medição de Risco , Triazóis/toxicidade
5.
Proc Biol Sci ; 281(1781): 20133296, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24598425

RESUMO

Extinction risk has been linked to biological and anthropogenic variables. Prediction of extinction risk in valuable fauna may not follow mainstream drivers when species are exploited for international markets. We use results from an International Union for Conservation of Nature Red List assessment of extinction risk in all 377 known species of sea cucumber within the order Aspidochirotida, many of which are exploited worldwide as luxury seafood for Asian markets. Extinction risk was primarily driven by high market value, compounded by accessibility and familiarity (well known) in the marketplace. Extinction risk in marine animals often relates closely to body size and small geographical range but our study shows a clear exception. Conservation must not lose sight of common species, especially those of high value. Greater human population density and poorer economies in the geographical ranges of endangered species illustrate that anthropogenic variables can also predict extinction risks in marine animals. Local-level regulatory measures must prevent opportunistic exploitation of high-value species. Trade agreements, for example CITES, may aid conservation but will depend on international technical support to low-income tropical countries. The high proportion of data deficient species also stresses a need for research on the ecology and population demographics of unglamorous invertebrates.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Espécies em Perigo de Extinção , Extinção Biológica , Pepinos-do-Mar/fisiologia , Alimentos Marinhos/estatística & dados numéricos , Análise de Variância , Animais , Pesqueiros/estatística & dados numéricos , Oceanos e Mares , Alimentos Marinhos/economia
6.
PLoS One ; 7(7): e39825, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22808066

RESUMO

Parrotfishes and surgeonfishes perform important functional roles in the dynamics of coral reef systems. This is a consequence of their varied feeding behaviors ranging from targeted consumption of living plant material (primarily surgeonfishes) to feeding on detrital aggregates that are either scraped from the reef surface or excavated from the deeper reef substratum (primarily parrotfishes). Increased fishing pressure and widespread habitat destruction have led to population declines for several species of these two groups. Species-specific data on global distribution, population status, life history characteristics, and major threats were compiled for each of the 179 known species of parrotfishes and surgeonfishes to determine the likelihood of extinction of each species under the Categories and Criteria of the IUCN Red List of Threatened Species. Due in part to the extensive distributions of most species and the life history traits exhibited in these two families, only three (1.7%) of the species are listed at an elevated risk of global extinction. The majority of the parrotfishes and surgeonfishes (86%) are listed as Least Concern, 10% are listed as Data Deficient and 1% are listed as Near Threatened. The risk of localized extinction, however, is higher in some areas, particularly in the Coral Triangle region. The relatively low proportion of species globally listed in threatened Categories is highly encouraging, and some conservation successes are attributed to concentrated conservation efforts. However, with the growing realization of man's profound impact on the planet, conservation actions such as improved marine reserve networks, more stringent fishing regulations, and continued monitoring of the population status at the species and community levels are imperative for the prevention of species loss in these groups of important and iconic coral reef fishes.


Assuntos
Recifes de Corais , Espécies em Perigo de Extinção/tendências , Comportamento Alimentar/fisiologia , Herbivoria/fisiologia , Perciformes/fisiologia , Dinâmica Populacional , Animais , Antozoários/fisiologia , Oceano Atlântico , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção/estatística & dados numéricos , Extinção Biológica , Oceano Pacífico , Probabilidade , Especificidade da Espécie
7.
PLoS One ; 5(4): e10095, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20386710

RESUMO

Mangrove species are uniquely adapted to tropical and subtropical coasts, and although relatively low in number of species, mangrove forests provide at least US $1.6 billion each year in ecosystem services and support coastal livelihoods worldwide. Globally, mangrove areas are declining rapidly as they are cleared for coastal development and aquaculture and logged for timber and fuel production. Little is known about the effects of mangrove area loss on individual mangrove species and local or regional populations. To address this gap, species-specific information on global distribution, population status, life history traits, and major threats were compiled for each of the 70 known species of mangroves. Each species' probability of extinction was assessed under the Categories and Criteria of the IUCN Red List of Threatened Species. Eleven of the 70 mangrove species (16%) are at elevated threat of extinction. Particular areas of geographical concern include the Atlantic and Pacific coasts of Central America, where as many as 40% of mangroves species present are threatened with extinction. Across the globe, mangrove species found primarily in the high intertidal and upstream estuarine zones, which often have specific freshwater requirements and patchy distributions, are the most threatened because they are often the first cleared for development of aquaculture and agriculture. The loss of mangrove species will have devastating economic and environmental consequences for coastal communities, especially in those areas with low mangrove diversity and high mangrove area or species loss. Several species at high risk of extinction may disappear well before the next decade if existing protective measures are not enforced.


Assuntos
Espécies em Perigo de Extinção/estatística & dados numéricos , Rhizophoraceae , América Central , Ecossistema , Espécies em Perigo de Extinção/economia , Espécies em Perigo de Extinção/tendências , Extinção Biológica , Probabilidade , Árvores/crescimento & desenvolvimento
8.
J Environ Monit ; 11(10): 1866-74, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19809710

RESUMO

Semi-permeable membrane devices (SPMDs) provide an informative and cost-effective approach for monitoring contaminants in remote tropical streams. Estimation and interpretation of contaminant concentrations in streams derived from SPMDs can vary based on a number of environmental factors, including stream flow, biofouling, and deployment time. In three one-month long trials, SPMDs were concurrently deployed for 4, 15, and 28 days at three stream sites in an extensive agricultural area of southeastern Costa Rica. Water, bottom sediment, and suspended solids grab samples were also collected and several environmental variables were monitored at corresponding time intervals during each month-long study period. At all three sites, SPMD concentrations of the widely used insecticide chlorpyrifos increased with deployment time, with no relationship between SPMD biofouling and pesticide sequestration. Differences in SPMD chlorpyrifos sequestration among sites are likely due to differences in stream chlorpyrifos concentration rather than differences in SPMD sampling rates. The longer exposure period of SPMDs allowed for the detection of lower concentrations of chlorpyrifos, terbufos, and difenoconazole compared to water grab samples. In addition to the use of appropriate performance reference compounds (PRCs), other environmental variables such as stream turbidity, flow regime, stream morphology, and knowledge of pesticide application methods are important considerations for optimizing SPMD deployment and data interpretation in tropical regions.


Assuntos
Incrustação Biológica , Monitoramento Ambiental/métodos , Praguicidas/análise , Rios , Clima Tropical , Movimentos da Água , Poluentes Químicos da Água/análise , Clorpirifos/análise , Costa Rica , Monitoramento Ambiental/instrumentação , Medição de Risco , Fatores de Tempo
9.
Science ; 321(5888): 560-3, 2008 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-18653892

RESUMO

The conservation status of 845 zooxanthellate reef-building coral species was assessed by using International Union for Conservation of Nature Red List Criteria. Of the 704 species that could be assigned conservation status, 32.8% are in categories with elevated risk of extinction. Declines in abundance are associated with bleaching and diseases driven by elevated sea surface temperatures, with extinction risk further exacerbated by local-scale anthropogenic disturbances. The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds that of most terrestrial groups. The Caribbean has the largest proportion of corals in high extinction risk categories, whereas the Coral Triangle (western Pacific) has the highest proportion of species in all categories of elevated extinction risk. Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures.


Assuntos
Antozoários , Clima , Ecossistema , Extinção Biológica , Água do Mar , Animais , Antozoários/classificação , Antozoários/crescimento & desenvolvimento , Região do Caribe , Conservação dos Recursos Naturais , Efeito Estufa , Oceano Índico , Oceano Pacífico , Medição de Risco , Especificidade da Espécie , Temperatura
10.
Environ Res ; 108(1): 98-106, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18555986

RESUMO

The use of pesticides in the cultivation of cash crops such as banana and plantain is increasing, in Costa Rica and worldwide. Agrochemical use and occupational and environmental exposures in export banana production have been documented in some parts of Central America. However, the extent of agrochemical use, agricultural pest knowledge, and economic components in plantain production are largely unknown in Costa Rica, especially in remote, high-poverty areas such as the Bribri-Cabécar Indigenous Territories. Our objective was to integrate a rapid rural appraisal of indigenous farmer pesticide application practices and pest knowledge with a cost-benefit analysis of plantain production in the Bribri-Cabécar Indigenous Territories, for the development of better agricultural management practices and improved regulatory infrastructure. Interviews conducted with 75 households in 5 indigenous communities showed that over 60% of participants grew plantain with agrochemicals. Of these plantain farmers, over 97% used the insecticide chlorpyrifos, and 84% applied nematicides, 64% herbicides, and 22% fungicides, with only 31% of participants reporting the use of some type of protective clothing during application. The banana weevil (Cosmopolites sordidus Germar) was ranked as the most important agricultural pest by 85% of participants, yet only 28% could associate the adult and larval form. A cost-benefit analysis conducted with a separate group of 26 plantain farmers identified several national markets and one export market for plantain production in the Indigenous Territories. Yearly income averaged US$6200/ha and yearly expenses averaged US$1872/ha, with an average cost-benefit ratio of 3.67 for plantain farmers. Farmers applied an average of 9.7 kg a.i./ha/yr of pesticide products and 375 kg/ha/yr of fertilizer, but those who sold their fruit to the national markets applied more nematicides, herbicides, and fertilizers than those who sold primarily to export markets, suggesting a lack of appropriate application knowledge. Results indicate that the quantity of agrochemicals applied in plantain cultivation is less than that applied in export banana, but the absence of appropriate agrochemical application practices in plantain cultivation may pose serious risks to human and environmental health. Culturally appropriate farmer education and certification programs are needed as well as the development of safe-handling practices, regulatory infrastructure, and adequate agrochemical storage, transport, and waste disposal facilities. Long-term solutions however, are dependent on the development of policies and infrastructure that support non-chemical pest management, alternatives to pesticides, and the identification of organic plantain markets.


Assuntos
Análise Custo-Benefício , Produtos Agrícolas , Insetos , Praguicidas , Animais , Costa Rica , Humanos , Insetos/classificação , População Rural
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