RESUMO
Concern about humanity's detachment from nature has spawned a global push to increase the availability of green spaces within cities. One impetus for this movement is a growing collection of studies documenting an association between improved human well-being and exposure to nature. The challenge lies in translating this research into pragmatic recommendations for cities. The usefulness of the existing research portfolio is diminished by the limitations of prevailing research designs. For example, most nature exposure studies (>80%) are observational. The rare randomized manipulative experiments tend to be indoors or virtual and rely on nature exposures on the order of ten to fifteen minutes. "Nature" and "biodiversity" are commonly invoked together as benefiting human well-being despite little evidence that biodiversity has particular importance for human psychological and emotional health. The most glaring gap in nature exposure research is the neglect of differences among cultures and ethnic groups with respect to the nature they prefer. In the few cases where researchers looked for differences among groups, they often found heterogeneous responses. Finally, few studies have compared greening interventions to other possible efforts to improve urban life. Thus, the utopian city of the future might be resplendent with urban parks on every block, but it is not clear whether those parks should offer basketball and pickleball courts, or small woodlands with a cornucopia of birds. We advocate for the next generation of nature exposure research that better informs the envisioning of our future sustainable cities with enhanced and equitable access to nature.
Assuntos
Biodiversidade , Saúde Mental , Humanos , Cidades , Florestas , EmoçõesRESUMO
A hallmark of the media publicity surrounding COVID-19 has been the message that land change causes zoonotic diseases to spill over from wild animals to humans. The secondary peer-reviewed literature sends a similar message. However, as indicated in the primary peer-reviewed literature, the complexity of interacting variables involved in zoonotic disease spillover makes it unlikely for such a claim to be universally applicable. The secondary peer-reviewed literature and the mainstream media also differ markedly from the primary peer-reviewed literature in their lack of nuance in messaging about the relationship between land change and spillover risk. We advocate accurate, nuanced messaging for the sake of the local communities at greatest risk from zoonotic disease, for the sake of scientific credibility, and so that proportionate attention may be given to other possible drivers of spillover risk.
RESUMO
The core idea of the Millennium Ecosystem Assessment is that the human condition is tightly linked to environmental condition. This assertion suggests that conservation and development projects should be able to achieve both ecological and social progress without detracting from their primary objectives. Whereas "win-win" projects that achieve both conservation and economic gains are a commendable goal, they are not easy to attain. An analysis of World Bank projects with objectives of alleviating poverty and protecting biodiversity revealed that only 16% made major progress on both objectives. Here, we provide a framework for anticipating win-win, lose-lose, and win-lose outcomes as a result of how people manage their ecosystem services. This framework emerges from detailed explorations of several case studies in which biodiversity conservation and economic development coincide and cases in which there is joint failure. We emphasize that scientific advances around ecosystem service production functions, tradeoffs among multiple ecosystem services, and the design of appropriate monitoring programs are necessary for the implementation of conservation and development projects that will successfully advance both environmental and social goals. The potentially bright future of jointly advancing ecosystem services, conservation, and human well-being will be jeopardized unless a global monitoring effort is launched that uses the many ongoing projects as a grand experiment.
Assuntos
Conservação dos Recursos Naturais/métodos , Economia/tendências , Ecossistema , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/tendências , Humanos , PobrezaRESUMO
The tiered approach to assessing ecological risk of insect-resistant transgenic crops assumes that lower tier laboratory studies, which expose surrogate non-target organisms to high doses of insecticidal proteins, can detect harmful effects that might be manifested in the field. To test this assumption, we performed meta-analyses comparing results for non-target invertebrates exposed to Bacillus thuringiensis (Bt) Cry proteins in laboratory studies with results derived from independent field studies examining effects on the abundance of non-target invertebrates. For Lepidopteran-active Cry proteins, laboratory studies correctly predicted the reduced field abundance of non-target Lepidoptera. However, laboratory studies incorporating tri-trophic interactions of Bt plants, herbivores and parasitoids were better correlated with the decreased field abundance of parasitoids than were direct-exposure assays. For predators, laboratory tri-trophic studies predicted reduced abundances that were not realized in field studies and thus overestimated ecological risk. Exposure to Coleopteran-active Cry proteins did not significantly reduce the laboratory survival or field abundance of any functional group examined. Our findings support the assumption that laboratory studies of transgenic insecticidal crops show effects that are either consistent with, or more conservative than, those found in field studies, with the important caveat that laboratory studies should explore all ecologically relevant routes of exposure.
Assuntos
Proteínas de Bactérias/toxicidade , Produtos Agrícolas/química , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Invertebrados/efeitos dos fármacos , Controle Biológico de Vetores/métodos , Plantas Geneticamente Modificadas/química , Animais , Toxinas de Bacillus thuringiensis , Controle Biológico de Vetores/estatística & dados numéricos , Medição de Risco , Especificidade da EspécieRESUMO
The Nature Conservancy (TNC) was founded by ecologists as a United States land trust to purchase parcels of habitat for the purpose of scientific study. It has evolved into a global organization working in 35 countries 'to conserve the lands and waters on which all life depends'. TNC is now the world 's largest conservation non-governmental organization (NGO), an early adopter of advances in ecological theory and a producer of new science as a result of practising conservation.The Nature Conservancy 's initial scientific innovation was the use of distributional data for rare species and ecological communities to systematically target lands for conservation. This innovation later evolved into a more rigorous approach known as 'Conservation by Design' that contained elements of systematic conservation planning, strategic planning and monitoring and evaluation.The next scientific transition at TNC was a move to landscape-scale projects, motivated by ideas from landscape ecology. Because the scale at which land could be set aside in areas untouched by humans fell far short of the spatial scale demanded by conservation, TNC became involved with best management practices for forestry, grazing, agriculture, hydropower and other land uses.A third scientific innovation at TNC came with the pursuit of multiobjective planning that accounts for economic and resource needs in the same plans that seek to protect biodiversity.The Millennium Ecosystem Assessment prompted TNC to become increasingly concerned with ecosystem services and the material risk to people posed by ecosystem deterioration.Finally, because conservation depends heavily upon negotiation, TNC has recently recruited social scientists, economists and communication experts. One aspect still missing, however, is a solid scientific understanding of thresholds that should be averted.Synthesis and applications. Over its 60-plus year history, scientific advances have informed The Nature Conservancy (TNC) 's actions and strategies, and in turn the evolving practice of conservation has altered the type of science sought by TNC in order to maximize its conservation effectiveness.
Assuntos
Biodiversidade , Conservação dos Recursos Naturais/economia , Saúde , Pobreza/prevenção & controle , Animais , Animais Selvagens , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Países em Desenvolvimento/economia , Ecossistema , Humanos , Plantas , Áreas de Pobreza , ÁguaRESUMO
Previous European guidance for environmental risk assessment of genetically modified plants emphasized the concepts of statistical power but provided no explicit requirements for the provision of statistical power analyses. Similarly, whilst the need for good experimental designs was stressed, no minimum guidelines were set for replication or sample sizes. Furthermore, although substantial equivalence was stressed as central to risk assessment, no means of quantification of this concept was given. This paper suggests several ways in which existing guidance might be revised to address these problems. One approach explored is the ;bioequivalence' test, which has the advantage that the error of most concern to the consumer may be set relatively easily. Also, since the burden of proof is placed on the experimenter, the test promotes high-quality, well-replicated experiments with sufficient statistical power. Other recommendations cover the specification of effect sizes, the choice of appropriate comparators, the use of positive controls, meta-analyses, multivariate analysis and diversity indices. Specific guidance is suggested for experimental designs of field trials and their statistical analyses. A checklist for experimental design is proposed to accompany all environmental risk assessments.
Assuntos
Monitoramento Ambiental , Controle de Pragas/métodos , Plantas Geneticamente Modificadas , Medição de Risco , Ração Animal , Animais , Qualidade de Produtos para o Consumidor , Manipulação de Alimentos/métodos , Humanos , Modelos Estatísticos , Valor Nutritivo , Vigilância de Produtos Comercializados , Testes de ToxicidadeRESUMO
BACKGROUND: Honey bees (Apis mellifera L.) are the most important pollinators of many agricultural crops worldwide and are a key test species used in the tiered safety assessment of genetically engineered insect-resistant crops. There is concern that widespread planting of these transgenic crops could harm honey bee populations. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a meta-analysis of 25 studies that independently assessed potential effects of Bt Cry proteins on honey bee survival (or mortality). Our results show that Bt Cry proteins used in genetically modified crops commercialized for control of lepidopteran and coleopteran pests do not negatively affect the survival of either honey bee larvae or adults in laboratory settings. CONCLUSIONS/SIGNIFICANCE: Although the additional stresses that honey bees face in the field could, in principle, modify their susceptibility to Cry proteins or lead to indirect effects, our findings support safety assessments that have not detected any direct negative effects of Bt crops for this vital insect pollinator.
Assuntos
Toxinas Bacterianas , Abelhas , Produtos Agrícolas , Precursores de Proteínas , AnimaisRESUMO
Although scores of experiments have examined the ecological consequences of transgenic Bacillus thuringiensis (Bt) crops, debates continue regarding the nontarget impacts of this technology. Quantitative reviews of existing studies are crucial for better gauging risks and improving future risk assessments. To encourage evidence-based risk analyses, we constructed a searchable database for nontarget effects of Bt crops. A meta-analysis of 42 field experiments indicates that nontarget invertebrates are generally more abundant in Bt cotton and Bt maize fields than in nontransgenic fields managed with insecticides. However, in comparison with insecticide-free control fields, certain nontarget taxa are less abundant in Bt fields.
Assuntos
Artrópodes , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Produtos Agrícolas/genética , Endotoxinas/genética , Gossypium/genética , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas , Zea mays/genética , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Produtos Agrícolas/crescimento & desenvolvimento , Bases de Dados Factuais , Gossypium/crescimento & desenvolvimento , Insetos , Inseticidas , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Dinâmica PopulacionalRESUMO
Species invasions are extremely common and are vastly outpacing the ability of resource agencies to address each invasion, one species at a time. Management actions that target the whole landscape or ecosystem may provide more cost-effective protection against the establishment of invasive species than a species-by-species approach. To explore what ecosystem-level actions might effectively reduce invasions, we developed a multispecies, multihabitat metapopulation model. We assume that species that successfully establish themselves outside their native range tend to be habitat generalists and that a tradeoff exists between competitive ability and habitat breadth, such that habitat specialists are competitively superior to habitat generalists. In this model, habitat destruction, fragmentation, and short-term disturbances all favor invasion by habitat generalists, despite the inferior competitive abilities of generalist species. Our model results illustrate that providing relatively undisturbed habitat and preventing further habitat degradation and fragmentation can provide a highly cost-effective defense against invasive species.