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1.
Nature ; 585(7826): 551-556, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908312

RESUMO

Increased efforts are required to prevent further losses to terrestrial biodiversity and the ecosystem services that it  provides1,2. Ambitious targets have been proposed, such as reversing the declining trends in biodiversity3; however, just feeding the growing human population will make this a challenge4. Here we use an ensemble of land-use and biodiversity models to assess whether-and how-humanity can reverse the declines in terrestrial biodiversity caused by habitat conversion, which is a major threat to biodiversity5. We show that immediate efforts, consistent with the broader sustainability agenda but of unprecedented ambition and coordination, could enable the provision of food for the growing human population while reversing the global terrestrial biodiversity trends caused by habitat conversion. If we decide to increase the extent of land under conservation management, restore degraded land and generalize landscape-level conservation planning, biodiversity trends from habitat conversion could become positive by the mid-twenty-first century on average across models (confidence interval, 2042-2061), but this was not the case for all models. Food prices could increase and, on average across models, almost half (confidence interval, 34-50%) of the future biodiversity losses could not be avoided. However, additionally tackling the drivers of land-use change could avoid conflict with affordable food provision and reduces the environmental effects of the food-provision system. Through further sustainable intensification and trade, reduced food waste and more plant-based human diets, more than two thirds of future biodiversity losses are avoided and the biodiversity trends from habitat conversion are reversed by 2050 for almost all of the models. Although limiting further loss will remain challenging in several biodiversity-rich regions, and other threats-such as climate change-must be addressed to truly reverse the declines in biodiversity, our results show that ambitious conservation efforts and food system transformation are central to an effective post-2020 biodiversity strategy.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Política Ambiental/tendências , Atividades Humanas/tendências , Dieta , Dieta Vegetariana/tendências , Abastecimento de Alimentos , Humanos , Desenvolvimento Sustentável/tendências
2.
Environ Sci Technol ; 58(6): 2627-2635, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38285505

RESUMO

The effect of an increase in crop productivity (output per unit of inputs) on biodiversity is hitherto poorly understood. This is because increased productivity of a crop in particular regions leads to increased profit that can encourage expansion of its cultivated area causing land use change and ultimately biodiversity loss, a phenomenon also known as "Jevons paradox" or the "rebound effect". Modeling such consequences in an interconnected and globalized world considering such rebound effects is challenging. Here, we discuss the use of computable general equilibrium (CGE) and other economic models in combination with ecological models to project consequences of crop productivity improvements for biodiversity globally. While these economic models have the advantage of taking into account market-mediated responses, resource constraints, endogenous price responses, and dynamic bilateral patterns of trade, there remain a number of important research and data gaps in these models which must be addressed to improve their performance in assessment of the link between local crop productivity changes and global biodiversity. To this end, we call for breaking the silos and building interdisciplinary networks across the globe to facilitate data sharing and knowledge exchange in order to improve global-to-local-to-global analysis of land, biodiversity, and ecosystem sustainability.


Assuntos
Agricultura , Ecossistema , Biodiversidade , Modelos Teóricos , Conservação dos Recursos Naturais
3.
Conserv Biol ; 37(6): e14138, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37377164

RESUMO

Following the failure to fully achieve any of the 20 Aichi biodiversity targets, the future of biodiversity rests in the balance. The Convention on Biological Diversity's Kunming-Montreal Global Biodiversity Framework (GBF) presents the opportunity to preserve nature's contributions to people (NCPs) for current and future generations by conserving biodiversity and averting extinctions. There is a need to safeguard the tree of life-the unique and shared evolutionary history of life on Earth-to maintain the benefits it bestows into the future. Two indicators have been adopted within the GBF to monitor progress toward safeguarding the tree of life: the phylogenetic diversity (PD) indicator and the evolutionarily distinct and globally endangered (EDGE) index. We applied both to the world's mammals, birds, and cycads to show their utility at the global and national scale. The PD indicator can be used to monitor the overall conservation status of large parts of the evolutionary tree of life, a measure of biodiversity's capacity to maintain NCPs for future generations. The EDGE index is used to monitor the performance of efforts to conserve the most distinctive species. The risk to PD of birds, cycads, and mammals increased, and mammals exhibited the greatest relative increase in threatened PD over time. These trends appeared robust to the choice of extinction risk weighting. EDGE species had predominantly worsening extinction risk. A greater proportion of EDGE mammals (12%) had increased extinction risk compared with threatened mammals in general (7%). By strengthening commitments to safeguarding the tree of life, biodiversity loss can be reduced and thus nature's capacity to provide benefits to humanity now and in the future can be preserved.


Indicadores para monitorear el estado del árbol de la vida Resumen El futuro de la biodiversidad peligra tras no haberse logrado ninguno de los 20 Objetivos de Aichi. El Marco Global de Biodiversidad (GBF) de Kunming-Montreal del Convenio sobre la Diversidad Biológica (CDB) representa la oportunidad de preservar las contribuciones de la naturaleza a las personas (PNC) para las generaciones actuales y futuras mediante la conservación de la biodiversidad y la prevención de las extinciones. Es necesario salvaguardar el árbol de la vida -la historia evolutiva única y compartida de la vida en la Tierra- para mantener en el futuro los beneficios que aporta. En el GBF se han adoptado dos indicadores para supervisar los avances hacia el cuidado del árbol de la vida: el indicador de diversidad filogenética y el índice de especies evolutivamente distintas y globalmente amenazadas (EDGE). Aplicamos ambos a los mamíferos, las aves y las cícadas del mundo para demostrar su utilidad a escala mundial y nacional. El indicador de diversidad filogenética puede utilizarse para supervisar el estado de conservación general de grandes partes del árbol evolutivo de la vida, una medida de la capacidad de la biodiversidad para mantener los PNC para las generaciones futuras. El índice EDGE se utiliza para supervisar el rendimiento de los esfuerzos por conservar las especies más distintivas. El riesgo para la diversidad filogenética de aves, cícadas y mamíferos aumentó, y los mamíferos mostraron el mayor aumento relativo de la diversidad filogenética amenazada a lo largo del tiempo. Estas tendencias parecieron sólidas a la hora de elegir la valoración del riesgo de extinción. Las especies EDGE tuvieron un riesgo de extinción predominante cada vez peor. Una mayor proporción de mamíferos EDGE (12%) presentó un riesgo de extinción creciente en comparación con los mamíferos amenazados en general (7%). Si se refuerza el compromiso de salvaguardar el árbol de la vida, se puede reducir la pérdida de biodiversidad y preservar así la capacidad de la naturaleza para proporcionar beneficios a la humanidad ahora y en el futuro.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Humanos , Animais , Filogenia , Biodiversidade , Mamíferos
4.
Ecol Eng ; 159: 1-13, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34975230

RESUMO

Vegetated buffers and filter strips are a widely used Best Management Practice (BMP) for enhancing streamside ecosystem quality and water quality improvement through nonpoint source pollutant removal. Most existing studies are either site-specific, rely on limited data points, or evaluate buffer width and slope as the only design variables for predicting sediment reduction, not considering other parameters such as soil texture, vegetation types, and runoff loads that can significantly influence the buffer efficiency. In this paper, we carry out a meta-analysis of published studies and fit regression models to explore the sediment removal capacity of riparian buffers. We compiled 905 data points from over 90 studies (including data from an online BMP database) documenting sediment trapping by vegetated buffers and recorded data regarding buffer characteristics such as buffer width, slope, area, vegetation type, sediment loading, water flow rates, and sediment removal efficiency. We found that an exponential regression model describing the relationship between sediment removal efficiency by the buffer and water inflow/outflow volume ratio explained 44% of the variance. Adding the square root of roughness increased the R 2 to 0.50. The model performance was compared with other sediment reduction regression models reported in the literature. The results point towards the importance of considering flow parameters in vegetative buffer design. The improved empirical relationships derived here can be used at local scales to understand sediment trapping potential by vegetated buffers for water quality mitigation purposes and can be built into extant hydrologic models for improved watershed-scale assessments.

7.
Environ Sci Technol ; 53(13): 7694-7703, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31145597

RESUMO

Current diets of most nations either do not meet the nutrition recommendations or transgress environmental planetary boundaries or both. Transitioning toward sustainable diets that are nutritionally adequate and low in environmental impact is key in achieving the United Nations' Sustainable Development Goals. However, designing region-specific sustainable diets that are culturally acceptable is a formidable challenge. Recent studies have suggested that optimization algorithms offer a potential solution to the above challenge, but the evidence is mostly based on case studies from high-income nations using widely varying constraints and algorithms. Here, we employ nonlinear optimization modeling with a consistent study design to identify diets for 152 countries that meet four cultural acceptability constraints, five food-related per capita environmental planetary boundaries (carbon emissions, water, land, nitrogen, and phosphorus use), and the daily recommended levels for 29 nutrients. The results show that a considerable departure from current dietary behavior is required for all countries. The required changes in intake amounts of 221 food items are highly country-specific but in general point toward a need to reduce the intake of meat, dairy, rice, and sugar and an increase in fruits, vegetables, pulses, nuts, and other grains. The constraints for fiber, vitamin B12, vitamin E, and saturated fats and the planetary boundaries for carbon emissions and nitrogen application were the most difficult to meet, suggesting the need to pay special attention to them. The analysis demonstrates that nonlinear optimization is a powerful tool to design diets achieving multiple objectives.


Assuntos
Dieta , Estado Nutricional , Algoritmos , Carne , Verduras
8.
J Theor Biol ; 438: 151-155, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29146280

RESUMO

The extinction of species at the present leads to the loss of 'phylogenetic diversity' (PD) from the evolutionary tree in which these species lie. Prior to extinction, the total PD present can be divided up among the species in various ways using measures of evolutionary isolation (such as 'fair proportion' and 'equal splits'). However, the loss of PD when certain combinations of species become extinct can be either larger or smaller than the cumulative loss of the isolation values associated with the extinct species. In this paper, we show that for trees generated under neutral evolutionary models, the loss of PD under a null model of random extinction at the present can be predicted from the loss of the cumulative isolation values, by applying a non-linear transformation that is independent of the tree. Moreover, the error in the prediction provably converges to zero as the size of the tree grows, with simulations showing good agreement even for moderate sized trees (n=64).


Assuntos
Biodiversidade , Extinção Biológica , Filogenia , Modelos Biológicos
9.
Environ Sci Technol ; 52(9): 5094-5104, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29648805

RESUMO

The UNEP-SETAC life cycle initiative recently recommended use of the countryside species-area relationship (SAR) model to calculate the characterization factors (CFs; potential species loss per m2) for projecting the biodiversity impact of land use associated with a products' life cycle. However, CFs based on this approach are to date available for only six broad land use types without differentiating between their management intensities and have large uncertainties that limit their practical applicability. Here we derive updated CFs for projecting potential species losses of five taxa resulting from five broad land use types (managed forests, plantations, pasture, cropland, urban) under three intensity levels (minimal, light, and intense use) in each of the 804 terrestrial ecoregions. We utilize recent global land use intensity maps and International Union for Conservation of Nature (IUCN) habitat classification scheme to parametrize the SAR model. As a case study, we compare the biodiversity impacts of 1 m3 of wood produced under four different forest management regimes in India and demonstrate that the new land use intensity-specific CFs have smaller uncertainty intervals and are able to discern the impacts of intensively managed land uses from the low intensity regimes, which has not been possible through previous CFs.


Assuntos
Biodiversidade , Florestas , Conservação dos Recursos Naturais , Ecossistema , Índia , Madeira
10.
Environ Sci Technol ; 50(7): 3928-36, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26914258

RESUMO

Anthropogenic land use to produce commodities for human consumption is the major driver of global biodiversity loss. Synergistic collaboration between producers and consumers in needed to halt this trend. In this study, we calculate species loss on 5 min × 5 min grid level and per country due to global agriculture, pasture and forestry by combining high-resolution land use data with countryside species area relationship for mammals, birds, amphibians, and reptiles. Results show that pasture was the primary driver of biodiversity loss in Madagascar, China and Brazil, while forest land use contributed the most to species loss in DR Congo and Indonesia. Combined with the yield data, we quantified the biodiversity impacts of 1 m(3) of roundwood produced in 139 countries, concluding that tropical countries with low timber yield and a large presence of vulnerable species suffer the highest impact. We also calculated impacts per kg for 160 crops grown in different countries and linked it with FAO food trade data to assess the biodiversity impacts embodied in Swiss food imports. We found that more than 95% of Swiss consumption impacts rest abroad with cocoa, coffee and palm oil imports being responsible for majority of damage.


Assuntos
Agricultura/métodos , Biodiversidade , Florestas , Análise Espacial , Animais , Aves , Produtos Agrícolas/crescimento & desenvolvimento , Alimentos , Geografia , Humanos , Mamíferos/fisiologia , Suíça
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