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1.
Trends Ecol Evol ; 35(5): 407-414, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32294422

RESUMO

The first Global Assessment of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) found widespread, accelerating declines in Earth's biodiversity and associated benefits to people from nature. Addressing these trends will require science-based policy responses to reduce impacts, especially at national to local scales. Effective scaling of science-policy efforts, driven by global and national assessments, is a major challenge for turning assessment into action and will require unprecedented commitment by scientists to engage with communities of policy and practice. Fulfillment of science's social contract with society, and with nature, will require strong institutional support for scientists' participation in activities that transcend conventional research and publication.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Planeta Terra , Políticas
2.
Nat Ecol Evol ; 3(4): 708, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30858593

RESUMO

The original paper was published without unique DOIs for GBIF occurrence downloads. These have now been inserted as references 70-76, and the error has been corrected in the PDF and HTML versions of the article.

3.
Nat Ecol Evol ; 2(12): 1889-1896, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30397301

RESUMO

A foundational paradigm in biological and Earth sciences is that our planet is divided into distinct ecoregions and biomes demarking unique assemblages of species. This notion has profoundly influenced scientific research and environmental policy. Given recent advances in technology and data availability, however, we are now poised to ask whether ecoregions meaningfully delimit biological communities. Using over 200 million observations of plants, animals and fungi we show compelling evidence that ecoregions delineate terrestrial biodiversity patterns. We achieve this by testing two competing hypotheses: the sharp-transition hypothesis, positing that ecoregion borders divide differentiated biotic communities; and the gradual-transition hypothesis, proposing instead that species turnover is continuous and largely independent of ecoregion borders. We find strong support for the sharp-transition hypothesis across all taxa, although adherence to ecoregion boundaries varies across taxa. Although plant and vertebrate species are tightly linked to sharp ecoregion boundaries, arthropods and fungi show weaker affiliations to this set of ecoregion borders. Our results highlight the essential value of ecological data for setting conservation priorities and reinforce the importance of protecting habitats across as many ecoregions as possible. Specifically, we conclude that ecoregion-based conservation planning can guide investments that simultaneously protect species-, community- and ecosystem-level biodiversity, key for securing Earth's life support systems into the future.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Biodiversidade , Ecologia
4.
Nat Commun ; 9(1): 5047, 2018 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-30487548

RESUMO

Understanding why some species are common and others are rare is a central question in ecology, and is critical for developing conservation strategies under global change. Rare species are typically considered to be more prone to extinction-but the fact they are rare can impede a general understanding of rarity vs. abundance. Here we develop and empirically test a framework to predict species abundances and stability using mechanisms governing population dynamics. Our results demonstrate that coexisting species with similar abundances can be shaped by different mechanisms (specifically, higher growth rates when rare vs. weaker negative density-dependence). Further, these dynamics influence population stability: species with higher intrinsic growth rates but stronger negative density-dependence were more stable and less sensitive to climate variability, regardless of abundance. This suggests that underlying mechanisms governing population dynamics, in addition to population size, may be critical indicators of population stability in an increasingly variable world.


Assuntos
Dinâmica Populacional , Animais , Mudança Climática , Ecologia , Densidade Demográfica
7.
Proc Natl Acad Sci U S A ; 110 Suppl 1: 3665-72, 2013 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-23297237

RESUMO

Efforts to develop a global understanding of the functioning of the Earth as a system began in the mid-1980s. This effort necessitated linking knowledge from both the physical and biological realms. A motivation for this development was the growing impact of humans on the Earth system and need to provide solutions, but the study of the social drivers and their consequences for the changes that were occurring was not incorporated into the Earth System Science movement, despite early attempts to do so. The impediments to integration were many, but they are gradually being overcome, which can be seen in many trends for assessments, such as the Intergovernmental Platform on Biodiversity and Ecosystem Services, as well as both basic and applied science programs. In this development, particular people and events have shaped the trajectories that have occurred. The lessons learned should be considered in such emerging research programs as Future Earth, the new global program for sustainability research. The transitioning process to this new program will take time as scientists adjust to new colleagues with different ideologies, methods, and tools and a new way of doing science.

8.
Curr Opin Environ Sustain ; 4(1): 101-105, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25104977

RESUMO

DIVERSITAS, the international programme on biodiversity science, is releasing a strategic vision presenting scientific challenges for the next decade of research on biodiversity and ecosystem services: "Biodiversity and Ecosystem Services Science for a Sustainable Planet". This new vision is a response of the biodiversity and ecosystem services scientific community to the accelerating loss of the components of biodiversity, as well as to changes in the biodiversity science-policy landscape (establishment of a Biodiversity Observing Network - GEO BON, of an Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services - IPBES, of the new Future Earth initiative; and release of the Strategic Plan for Biodiversity 2011-2020). This article presents the vision and its core scientific challenges.

11.
Philos Trans R Soc Lond B Biol Sci ; 365(1537): 31-9, 2010 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-20008383

RESUMO

The losses that are being incurred of the Earth's biological diversity, at all levels, are now staggering. The trend lines for future loss are steeply upward as new adverse drivers of change come into play. The political processes for matching this crisis are now inadequate and the science needs to address this issue are huge and slow to fulfil, even though strong advances have been made. A more integrated approach to evaluating biodiversity in terms that are meaningful to the larger community is needed that can provide understandable metrics of the consequences to society of the losses that are occurring. Greater attention is also needed in forecasting likely diversity-loss scenarios in the near term and strategies for alleviating detrimental consequences. At the international level, the Convention on Biological Diversity must be revisited to make it more powerful to meet the needs that originally motivated its creation. Similarly, at local and regional levels, an ecosystem-service approach to conservation can bring new understanding to the value, and hence the need for protection, of the existing natural capital.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Política , Animais , Extinção Biológica , Aquecimento Global , Humanos , Filosofia
12.
Trends Ecol Evol ; 24(9): 497-504, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19577817

RESUMO

Although the effects of invasive alien species (IAS) on native species are well documented, the many ways in which such species impact ecosystem services are still emerging. Here we assess the costs and benefits of IAS for provisioning, regulating and cultural services, and illustrate the synergies and tradeoffs associated with these impacts using case studies that include South Africa, the Great Lakes and Hawaii. We identify services and interactions that are the least understood and propose a research and policy framework for filling the remaining knowledge gaps. Drawing on ecology and economics to incorporate the impacts of IAS on ecosystem services into decision making is key to restoring and sustaining those life-support services that nature provides and all organisms depend upon.


Assuntos
Ecossistema , Animais , Great Lakes Region , Havaí , Humanos , Dinâmica Populacional , África do Sul
13.
Proc Natl Acad Sci U S A ; 106(5): 1305-12, 2009 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-19179280

RESUMO

The Millennium Ecosystem Assessment (MA) introduced a new framework for analyzing social-ecological systems that has had wide influence in the policy and scientific communities. Studies after the MA are taking up new challenges in the basic science needed to assess, project, and manage flows of ecosystem services and effects on human well-being. Yet, our ability to draw general conclusions remains limited by focus on discipline-bound sectors of the full social-ecological system. At the same time, some polices and practices intended to improve ecosystem services and human well-being are based on untested assumptions and sparse information. The people who are affected and those who provide resources are increasingly asking for evidence that interventions improve ecosystem services and human well-being. New research is needed that considers the full ensemble of processes and feedbacks, for a range of biophysical and social systems, to better understand and manage the dynamics of the relationship between humans and the ecosystems on which they rely. Such research will expand the capacity to address fundamental questions about complex social-ecological systems while evaluating assumptions of policies and practices intended to advance human well-being through improved ecosystem services.


Assuntos
Ecossistema , Meio Ambiente , Conservação dos Recursos Naturais , Humanos , Modelos Teóricos , Probabilidade , Especificidade da Espécie
14.
Trends Ecol Evol ; 22(7): 357-65, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17478009

RESUMO

Plants are finely tuned to the seasonality of their environment, and shifts in the timing of plant activity (i.e. phenology) provide some of the most compelling evidence that species and ecosystems are being influenced by global environmental change. Researchers across disciplines have observed shifting phenology at multiple scales, including earlier spring flowering in individual plants and an earlier spring green-up' of the land surface revealed in satellite images. Experimental and modeling approaches have sought to identify the mechanisms causing these shifts, as well as to make predictions regarding the consequences. Here, we discuss recent advances in several fields that have enabled scaling between species responses to recent climatic changes and shifts in ecosystem productivity, with implications for global carbon cycling.


Assuntos
Efeito Estufa , Plantas , Dióxido de Carbono , Ecossistema , Monitoramento Ambiental
15.
Ambio ; 36(8): 622-9, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18240675

RESUMO

This paper provides an original account of global land, water, and nitrogen use in support of industrialized livestock production and trade, with emphasis on two of the fastest-growing sectors, pork and poultry. Our analysis focuses on trade in feed and animal products, using a new model that calculates the amount of "virtual" nitrogen, water, and land used in production but not embedded in the product. We show how key meat-importing countries, such as Japan, benefit from "virtual" trade in land, water, and nitrogen, and how key meat-exporting countries, such as Brazil, provide these resources without accounting for their true environmental cost. Results show that Japan's pig and chicken meat imports embody the virtual equivalent of 50% of Japan's total arable land, and half of Japan's virtual nitrogen total is lost in the US. Trade links with China are responsible for 15% of the virtual nitrogen left behind in Brazil due to feed and meat exports, and 20% of Brazil's area is used to grow soybean exports. The complexity of trade in meat, feed, water, and nitrogen is illustrated by the dual roles of the US and The Netherlands as both importers and exporters of meat. Mitigation of environmental damage from industrialized livestock production and trade depends on a combination of direct-pricing strategies, regulatory approaches, and use of best management practices. Our analysis indicates that increased water- and nitrogen-use efficiency and land conservation resulting from these measures could significantly reduce resource costs.


Assuntos
Comércio , Conservação dos Recursos Naturais , Carne , Criação de Animais Domésticos , Animais , Galinhas , Cooperação Internacional , Nitrogênio , Suínos , Água
18.
Proc Natl Acad Sci U S A ; 103(37): 13740-4, 2006 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-16954189

RESUMO

Shifting plant phenology (i.e., timing of flowering and other developmental events) in recent decades establishes that species and ecosystems are already responding to global environmental change. Earlier flowering and an extended period of active plant growth across much of the northern hemisphere have been interpreted as responses to warming. However, several kinds of environmental change have the potential to influence the phenology of flowering and primary production. Here, we report shifts in phenology of flowering and canopy greenness (Normalized Difference Vegetation Index) in response to four experimentally simulated global changes: warming, elevated CO(2), nitrogen (N) deposition, and increased precipitation. Consistent with previous observations, warming accelerated both flowering and greening of the canopy, but phenological responses to the other global change treatments were diverse. Elevated CO(2) and N addition delayed flowering in grasses, but slightly accelerated flowering in forbs. The opposing responses of these two important functional groups decreased their phenological complementarity and potentially increased competition for limiting soil resources. At the ecosystem level, timing of canopy greenness mirrored the flowering phenology of the grasses, which dominate primary production in this system. Elevated CO(2) delayed greening, whereas N addition dampened the acceleration of greening caused by warming. Increased precipitation had no consistent impacts on phenology. This diversity of phenological changes, between plant functional groups and in response to multiple environmental changes, helps explain the diversity in large-scale observations and indicates that changing temperature is only one of several factors reshaping the seasonality of ecosystem processes.


Assuntos
Ecossistema , Flores/crescimento & desenvolvimento , Temperatura Alta , Poaceae/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Nitrogênio/metabolismo , Solo , Temperatura
19.
Ecol Lett ; 9(1): 86-94, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16958872

RESUMO

Selective consumption by herbivores influences the composition and structure of a range of plant communities. Anthropogenically driven global environmental changes, including increased atmospheric carbon dioxide (CO(2)), warming, increased precipitation, and increased N deposition, directly alter plant physiological properties, which may in turn modify herbivore consumption patterns. In this study, we tested the hypothesis that responses of annual grassland composition to global changes can be predicted exclusively from environmentally induced changes in the consumption patterns of a group of widespread herbivores, the terrestrial gastropods. This was done by: (1) assessing gastropod impacts on grassland composition under ambient conditions; (2) quantifying environmentally induced changes in gastropod feeding behaviour; (3) predicting how grassland composition would respond to global-change manipulations if influenced only by herbivore consumption preferences; and (4) comparing these predictions to observed responses of grassland community composition to simulated global changes. Gastropod herbivores consume nearly half of aboveground production in this system. Global changes induced species-specific changes in plant leaf characteristics, leading gastropods to alter the relative amounts of different plant types consumed. These changes in gastropod feeding preferences consistently explained global-change-induced responses of functional group abundance in an intact annual grassland exposed to simulated future environments. For four of the five global change scenarios, gastropod impacts explained > 50% of the quantitative changes, indicating that herbivore preferences can be a major driver of plant community responses to global changes.


Assuntos
Ecossistema , Comportamento Alimentar/fisiologia , Gastrópodes/fisiologia , Poaceae/fisiologia , Animais , Previsões , Dinâmica Populacional
20.
Ecology ; 87(3): 686-94, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16602298

RESUMO

In this study, the influence of elevated carbon dioxide (CO2) and nitrogen (N) deposition on gastropod herbivory was investigated for six annual species in a California annual grassland community. These experimentally simulated global changes increased availability of important resources for plant growth, leading to the hypothesis that species with the most positive growth and foliar nutrient responses would experience the greatest increase in herbivory. Counter to the expectations, shifts in tissue N and growth rates caused by N deposition did not predict shifts in herbivore consumption rates. N deposition increased seedling N concentrations and growth rates but did not increase herbivore consumption overall, or for any individual species. Elevated CO2 did not influence growth rates nor have a statistically significant influence on seedling N concentrations. Elevated CO2 at ambient N levels caused a decline in the number of seedlings consumed, but the interaction between CO2 and N addition differed among species. The results of this study indicate that shifting patterns of herbivory will likely influence species composition as environmental conditions change in the future; however, a simple trade-off between shifting growth rates and palatability is not evident.


Assuntos
Dióxido de Carbono/farmacologia , Gastrópodes/crescimento & desenvolvimento , Nitrogênio/farmacologia , Poaceae , Animais , Atmosfera , California , Dióxido de Carbono/metabolismo , Ecossistema , Nitrogênio/metabolismo , Folhas de Planta , Poaceae/crescimento & desenvolvimento , Poaceae/parasitologia , Densidade Demográfica , Dinâmica Populacional , Especificidade da Espécie
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