Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nature ; 629(8013): 837-842, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38693262

RESUMO

The record of past human adaptations provides crucial lessons for guiding responses to crises in the future1-3. To date, there have been no systematic global comparisons of humans' ability to absorb and recover from disturbances through time4,5. Here we synthesized resilience across a broad sample of prehistoric population time-frequency data, spanning 30,000 years of human history. Cross-sectional and longitudinal analyses of population decline show that frequent disturbances enhance a population's capacity to resist and recover from later downturns. Land-use patterns are important mediators of the strength of this positive association: farming and herding societies are more vulnerable but also more resilient overall. The results show that important trade-offs exist when adopting new or alternative land-use strategies.


Assuntos
Agricultura , Dinâmica Populacional , Mudança Social , Agricultura/história , Agricultura/estatística & dados numéricos , Estudos Transversais , História Antiga , Estudos Longitudinais , Dinâmica Populacional/história , Dinâmica Populacional/estatística & dados numéricos , Resiliência Psicológica , Mudança Social/história , Humanos
2.
Environ Sci Technol ; 56(3): 1736-1742, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35034441

RESUMO

Lead and mercury have long histories of anthropogenic use and release to the environment extending into preindustrial times. Yet, the timing, magnitude, and persistence of preindustrial emissions remain enigmatic, especially for mercury. Here, we quantify tropical lead and mercury deposition over the past ∼3000 years using a well-dated sediment core from a small crater lake (Lake Antoine, Grenada). Preindustrial increases in lead and mercury concentrations can be explained by varying inputs of watershed mineral and organic matter, which in turn reflect climate-driven changes in the lake level. We find no evidence that preindustrial lead and mercury use raised deposition rates in this remote ecosystem, and our results underscore the need to carefully evaluate common normalization approaches for changing lithogenic inputs and sedimentation rates. Industrial-era lead and mercury accumulation rates in Lake Antoine have been accelerated by land use and land cover change within the crater rim, yet global industrial pollution remains evident. After correcting for watershed inputs, we find that recent atmospheric lead and mercury deposition rates averaged 2925 and 24 µg/m2/y, respectively, which are in close agreement with monitoring data. Our results challenge recent assessments suggesting preindustrial mercury use raised atmospheric deposition rates globally, highlighting the unique nature of 20th Century industrial pollution.


Assuntos
Mercúrio , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Mercúrio/análise , Poluentes Químicos da Água/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA