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6.
Nature ; 613(7944): 503-507, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36653569

RESUMEN

The Greenland Ice Sheet has a central role in the global climate system owing to its size, radiative effects and freshwater storage, and as a potential tipping point1. Weather stations show that the coastal regions are warming2, but the imprint of global warming in the central part of the ice sheet is unclear, owing to missing long-term observations. Current ice-core-based temperature reconstructions3-5 are ambiguous with respect to isolating global warming signatures from natural variability, because they are too noisy and do not include the most recent decades. By systematically redrilling ice cores, we created a high-quality reconstruction of central and north Greenland temperatures from AD 1000 until 2011. Here we show that the warming in the recent reconstructed decade exceeds the range of the pre-industrial temperature variability in the past millennium with virtual certainty (P < 0.001) and is on average 1.5 ± 0.4 degrees Celsius (1 standard error) warmer than the twentieth century. Our findings suggest that these exceptional temperatures arise from the superposition of natural variability with a long-term warming trend, apparent since AD 1800. The disproportionate warming is accompanied by enhanced Greenland meltwater run-off, implying that anthropogenic influence has also arrived in central and north Greenland, which might further accelerate the overall Greenland mass loss.


Asunto(s)
Clima , Calentamiento Global , Temperatura , Calentamiento Global/estadística & datos numéricos , Groenlandia , Cubierta de Hielo , Actividades Humanas/tendencias , Movimientos del Agua , Congelación
8.
PLoS Biol ; 19(5): e3001195, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34010287

RESUMEN

Protected areas are the flagship management tools to secure biodiversity from anthropogenic impacts. However, the extent to which adjacent areas with distinct protection levels host different species numbers and compositions remains uncertain. Here, using reef fishes, European alpine plants, and North American birds, we show that the composition of species in adjacent Strictly Protected, Restricted, and Non-Protected areas is highly dissimilar, whereas the number of species is similar, after controlling for environmental conditions, sample size, and rarity. We find that between 12% and 15% of species are only recorded in Non-Protected areas, suggesting that a non-negligible part of regional biodiversity occurs where human activities are less regulated. For imperiled species, the proportion only recorded in Strictly Protected areas reaches 58% for fishes, 11% for birds, and 7% for plants, highlighting the fundamental and unique role of protected areas and their environmental conditions in biodiversity conservation.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Seguimiento de Parámetros Ecológicos/métodos , Parques Recreativos/tendencias , Animales , Biodiversidad , Aves , Ecosistema , Peces , Actividades Humanas/tendencias , Humanos , Parques Recreativos/normas , Plantas
9.
Nature ; 585(7826): 551-556, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32908312

RESUMEN

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.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/tendencias , Política Ambiental/tendencias , Actividades Humanas/tendencias , Dieta , Dieta Vegetariana/tendencias , Abastecimiento de Alimentos , Humanos , Desarrollo Sostenible/tendencias
10.
PLoS Biol ; 18(9): e3000818, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32960897

RESUMEN

Humans profoundly impact landscapes, ecosystems, and animal behavior. In many cases, animals living near humans become tolerant of them and reduce antipredator responses. Yet, we still lack an understanding of the underlying evolutionary dynamics behind these shifts in traits that affect animal survival. Here, we used a phylogenetic meta-analysis to determine how the mean and variability in antipredator responses change as a function of the number of generations spent in contact with humans under 3 different contexts: urbanization, captivity, and domestication. We found that any contact with humans leads to a rapid reduction in mean antipredator responses as expected. Notably, the variance among individuals over time observed a short-term increase followed by a gradual decrease, significant for domesticated animals. This implies that intense human contact immediately releases animals from predation pressure and then imposes strong anthropogenic selection on traits. In addition, our results reveal that the loss of antipredator traits due to urbanization is similar to that of domestication but occurs 3 times more slowly. Furthermore, the rapid disappearance of antipredator traits was associated with 2 main life-history traits: foraging guild and whether the species was solitary or gregarious (i.e., group-living). For domesticated animals, this decrease in antipredator behavior was stronger for herbivores than for omnivores or carnivores and for solitary than for gregarious species. By contrast, the decrease in antipredator traits was stronger for gregarious, urbanized species, although this result is based mostly on birds. Our study offers 2 major insights on evolution in the Anthropocene: (1) changes in traits occur rapidly even under unintentional human "interventions" (i.e., urbanization) and (2) there are similarities between the selection pressures exerted by domestication and by urbanization. In all, such changes could affect animal survival in a predator-rich world, but through understanding evolutionary dynamics, we can better predict when and how exposure to humans modify these fitness-related traits.


Asunto(s)
Conducta Animal/fisiología , Evolución Biológica , Carnívoros/fisiología , Actividades Humanas , Conducta Predatoria/fisiología , Animales , Carnívoros/clasificación , Domesticación , Ecosistema , Actividades Humanas/tendencias , Humanos , Rasgos de la Historia de Vida , Fenotipo , Urbanización/tendencias
11.
Commun Biol ; 3(1): 391, 2020 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-32694629

RESUMEN

A dramatic increase in the hybridization between historically allopatric species has been induced by human activities. However, the notion of hybridization seems to lack consistency in two respects. On the one hand, it is inconsistent with the biological species concept, which does not allow for interbreeding between species, and on the other hand, it is considered either as an evolutionary process leading to the emergence of new biodiversity or as a cause of biodiversity loss, with conservation implications. In the first case, we argue that conservation biology should avoid the discussion around the species concept and delimit priorities of conservation units based on the impact on biodiversity if taxa are lost. In the second case, we show that this is not a paradox but an intrinsic property of hybridization, which should be considered in conservation programmes. We propose a novel view of conservation guidelines, in which human-induced hybridization may also be a tool to enhance the likelihood of adaptation to changing environmental conditions or to increase the genetic diversity of taxa affected by inbreeding depression. The conservation guidelines presented here represent a guide for the development of programmes aimed at protecting biodiversity as a dynamic evolutionary system.


Asunto(s)
Adaptación Fisiológica/genética , Evolución Biológica , Conservación de los Recursos Naturales , Hibridación Genética/genética , Biodiversidad , Actividades Humanas/tendencias , Humanos , Aislamiento Reproductivo
12.
Science ; 368(6488): 314-318, 2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32299953

RESUMEN

Severe and persistent 21st-century drought in southwestern North America (SWNA) motivates comparisons to medieval megadroughts and questions about the role of anthropogenic climate change. We use hydrological modeling and new 1200-year tree-ring reconstructions of summer soil moisture to demonstrate that the 2000-2018 SWNA drought was the second driest 19-year period since 800 CE, exceeded only by a late-1500s megadrought. The megadrought-like trajectory of 2000-2018 soil moisture was driven by natural variability superimposed on drying due to anthropogenic warming. Anthropogenic trends in temperature, relative humidity, and precipitation estimated from 31 climate models account for 47% (model interquartiles of 35 to 105%) of the 2000-2018 drought severity, pushing an otherwise moderate drought onto a trajectory comparable to the worst SWNA megadroughts since 800 CE.


Asunto(s)
Sequías , Calentamiento Global , Actividades Humanas/tendencias , Sequías/historia , Calentamiento Global/historia , Historia del Siglo XXI , Historia Medieval , Actividades Humanas/historia , Hidrología , Modelos Teóricos , América del Norte , Suelo
13.
J Gerontol B Psychol Sci Soc Sci ; 75(9): 2008-2017, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-31504873

RESUMEN

OBJECTIVES: Studies show that using information and communication technology (ICT) contributes significantly to elders' subjective well-being (SWB). Drawing on the Selective Optimization with Compensation (SOC) model, this study aims at exploring the mechanism by which ICT use helps older adults remain engaged in valued life activities and maintain their SWB. METHOD: Involving teams from seven countries (Canada, Colombia, Israel, Italy, Peru, Romania, Spain), 27 focus groups were conducted with a total of 184 grandmothers aged 65 years and older who use ICT. RESULTS: Analysis led to identification of a series of strategies related to ICT use that may be described in SOC terms. "Intentional limited use" and "Selective timing,", for example, are clearly associated with selection. In addition, numerous optimizing strategies were found to be applied in "Instrumental" and "Leisure" activities, whereas some ICT uses offered compensation for "Aging-related" and "General" challenging circumstances. DISCUSSION: The study suggests that ICT is used in all three SOC processes and that its effective application facilitates adjustment and enhances SWB. It should therefore be regarded as a resource that supports existing personal and social resources and life management strategies, and even as a Quality of Life Technology that maintains or enhances functioning in older adulthood.


Asunto(s)
Envejecimiento , Abuelos/psicología , Envejecimiento Saludable/psicología , Tecnología de la Información , Salud Mental , Calidad de Vida , Valor de la Vida , Anciano , Envejecimiento/fisiología , Envejecimiento/psicología , Refuerzo Biomédico , Autoevaluación Diagnóstica , Femenino , Actividades Humanas/psicología , Actividades Humanas/tendencias , Humanos , Tecnología de la Información/provisión & distribución , Tecnología de la Información/tendencias , Cooperación Internacional , Funcionamiento Psicosocial , Investigación Cualitativa , Proyectos de Investigación
14.
Science ; 366(6471)2019 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-31831642

RESUMEN

The human impact on life on Earth has increased sharply since the 1970s, driven by the demands of a growing population with rising average per capita income. Nature is currently supplying more materials than ever before, but this has come at the high cost of unprecedented global declines in the extent and integrity of ecosystems, distinctness of local ecological communities, abundance and number of wild species, and the number of local domesticated varieties. Such changes reduce vital benefits that people receive from nature and threaten the quality of life of future generations. Both the benefits of an expanding economy and the costs of reducing nature's benefits are unequally distributed. The fabric of life on which we all depend-nature and its contributions to people-is unravelling rapidly. Despite the severity of the threats and lack of enough progress in tackling them to date, opportunities exist to change future trajectories through transformative action. Such action must begin immediately, however, and address the root economic, social, and technological causes of nature's deterioration.


Asunto(s)
Conservación de los Recursos Naturales , Actividades Humanas/tendencias , Calidad de Vida , Planeta Tierra , Humanos , Crecimiento Demográfico
15.
Bull Soc Pathol Exot ; 112(2): 96-104, 2019.
Artículo en Francés | MEDLINE | ID: mdl-31478619

RESUMEN

Big cities have thrived on all continents, so have domestic and industrial wastes not to mention the often irrational use of agricultural inputs (fertilizers and pesticides) detrimental to plants and animals. One hundred and eighty million tons of fertilizers and 2.4 million tons of pesticides are spread every year worldwide. Such pollutions, whether urban or rural, have a significant impact on the biology of mosquitoes. Today some urban spaces have properly become a land of plenty for mosquitoes. The combined use of fertilizer and pesticides in the country, quite paradoxically also favor their proliferation. Ironically the very reasons that account for the multitudes of mosquitoes are the exact reasons responsible for the depletion of biodiversity.


Les grandes villes se sont multipliées sur tous les continents en générant des pollutions domestiques et industrielles et dans les campagnes, l'utilisation souvent irraisonnée des intrants agricoles (engrais et pesticides) déciment les plantes et les animaux. Cent quatre-vingt millions de tonnes d'engrais et 2,4 millions de tonnes de pesticides sont déversées chaque année dans le monde. Ces pollutions, qu'elles soient urbaines ou rurales, ont un impact considérable sur la biologie des moustiques. Aujourd'hui, certains espaces urbains sont devenus de véritables nids à moustiques et, dans les campagnes, l'usage combiné des engrais et des pesticides favorise, paradoxalement, leur prolifération. L'ironie de cette histoire du monde moderne est que les différents facteurs qui favorisent la pullulation des moustiques sont ceux là mêmes qui déciment une bonne partie de la biodiversité.


Asunto(s)
Agricultura , Culicidae/crecimiento & desarrollo , Contaminación Ambiental/efectos adversos , Actividades Humanas , Mosquitos Vectores/crecimiento & desarrollo , Agricultura/estadística & datos numéricos , Animales , Patógenos Transmitidos por la Sangre/aislamiento & purificación , Ciudades/estadística & datos numéricos , Reservorios de Enfermedades/microbiología , Reservorios de Enfermedades/parasitología , Reservorios de Enfermedades/estadística & datos numéricos , Reservorios de Enfermedades/virología , Contaminación Ambiental/estadística & datos numéricos , Fertilizantes/efectos adversos , Actividades Humanas/estadística & datos numéricos , Actividades Humanas/tendencias , Humanos , Plaguicidas/efectos adversos , Población Urbana/estadística & datos numéricos
17.
Parasitology ; 146(1): 74-88, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29781413

RESUMEN

The anthropogenic modification of natural landscapes, and the consequent changes in the environmental conditions and resources availability at multiple spatial scales can affect complex species interactions involving key-stone species such as bat-parasite interactions. In this study, we aimed to identify the drivers potentially influencing host-bat fly interactions at different spatial scales (at the host, vegetation stand and landscape level), in a tropical anthropogenic landscape. For this purpose, we mist-netted phyllostomid and moormopid bats and collected the bat flies (streblids) parasitizing them in 10 sites representing secondary and old growth forest. In general, the variation in fly communities largely mirrored the variation in bat communities as a result of the high level of specialization characterizing host-bat fly interaction networks. Nevertheless, we observed that: (1) bats roosting dynamics can shape bat-streblid interactions, modulating parasite prevalence and the intensity of infestation; (2) a degraded matrix could favor crowding and consequently the exchange of ectoparasites among bat species, lessening the level of specialization of the interaction networks and promoting novel interactions; and (3) bat-fly interaction can also be shaped by the dilution effect, as a decrease in bat diversity could be associated with a potential increase in the dissemination and prevalence of streblids.


Asunto(s)
Quirópteros/parasitología , Dípteros/fisiología , Animales , Ecosistema , Bosques , Interacciones Huésped-Parásitos , Actividades Humanas/tendencias , México , Clima Tropical
18.
Sci Total Environ ; 652: 1396-1408, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30586824

RESUMEN

Aquatic ecosystems are under severe pressure. Human activities introduce an array of pressures that impact ecosystems and their components. In this study we focus on the aquatic domains of fresh, coastal and marine waters, including rivers, lakes and riparian habitats to transitional, coastal as well as shelf and oceanic habitats. In an environmental risk assessment approach, we identified impact chains that link 45 human activities through 31 pressures to 82 ecosystem components. In this linkage framework >22,000 activity-pressure-ecosystem component interactions were found across seven European case studies. We identified the environmental impact risk posed by each impact chain by first categorically weighting the interactions according to five criteria: spatial extent, dispersal potential, frequency of interaction, persistence of pressure and severity of the interaction, where extent, dispersal, frequency and persistence account for the exposure to risk (spatial and temporal), and the severity accounts for the consequence of the risk. After assigning a numerical score to each risk criterion, we came up with an overall environmental impact risk score for each impact chain. This risk score was analysed in terms of (1) the activities and pressures that introduce the greatest risk to European aquatic domains, and (2) the aquatic ecosystem components and realms that are at greatest risk from human activities. Activities related to energy production were relevant across the aquatic domains. Fishing was highly relevant in marine and environmental engineering in fresh waters. Chemical and physical pressures introduced the greatest risk to the aquatic realms. Ecosystem components that can be seen as ecotones between different ecosystems had high impact risk. We show how this information can be used in informing management on trade-offs in freshwater, coastal and marine resource use and aid decision-making.


Asunto(s)
Conservación de los Recursos Hídricos/métodos , Ecosistema , Agua Dulce/química , Actividades Humanas/tendencias , Agua de Mar/química , Contaminación del Agua/análisis , Organismos Acuáticos/efectos de los fármacos , Humanos , Medición de Riesgo , Contaminación del Agua/efectos adversos
19.
Artículo en Inglés | MEDLINE | ID: mdl-30572613

RESUMEN

The Yangtze River Delta (YRD) region, including Shanghai City and the Jiangsu and Zhejiang Provinces, is the largest metropolitan region in China. In the past three decades, the region has experienced an unprecedented process of rapid and massive urbanization, which has dramatically altered the landscape and detrimentally affected the ecological environments in the region. In this paper, we analyzed the spatiotemporal variations of ecological conditions (Eco_C) via a synthetic index with analytic hierarchy processes in the YRD during 1990⁻2010. The relative contributions of influencing factors, including two natural conditions (i.e., elevation (Elev) and land-sea gradient (Dis_coa)), three indicators of human activities (i.e., urbanization rate (Urb_rate), per capita GDP (Per_gdp), the percentage of secondary and tertiary industry employment (Per_ind)), to the total variance of regional Eco_C were also investigated. The results showed that: (1) The Eco_C over YRD region was "Moderately High", which was better than the national average and demonstrated obvious spatial variations between south and north. There existed fluctuations and an overall increasing trend for Eco_C during the study period, with 20% of the area being deteriorated and 40% being improved. (2) The areas with elevation below 10 m was relatively poor in Eco_C, while the regions above 1000 m showed the best Eco_C and had the most obvious changes (9.33%) during the study period. (3) The selected five influencing factors could explain 91.0⁻94.4% of the Eco_C spatial variability. Elevation was the dominant factor for about 42.4⁻52.9%, while urbanization rate and per capita GDP were about 32.5% and 9.3%.


Asunto(s)
Ecología/tendencias , Actividades Humanas/estadística & datos numéricos , Actividades Humanas/tendencias , Industrias/estadística & datos numéricos , Industrias/tendencias , Urbanización/tendencias , China , Ciudades/estadística & datos numéricos , Monitoreo del Ambiente , Predicción , Humanos
20.
Nature ; 563(7731): 339-346, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30429550

RESUMEN

There is no consensus on whether climate change has yet affected the statistics of tropical cyclones, owing to their large natural variability and the limited period of consistent observations. In addition, projections of future tropical cyclone activity are uncertain, because they often rely on coarse-resolution climate models that parameterize convection and hence have difficulty in directly representing tropical cyclones. Here we used convection-permitting regional climate model simulations to investigate whether and how recent destructive tropical cyclones would change if these events had occurred in pre-industrial and in future climates. We found that, relative to pre-industrial conditions, climate change so far has enhanced the average and extreme rainfall of hurricanes Katrina, Irma and Maria, but did not change tropical cyclone wind-speed intensity. In addition, future anthropogenic warming would robustly increase the wind speed and rainfall of 11 of 13 intense tropical cyclones (of 15 events sampled globally). Additional regional climate model simulations suggest that convective parameterization introduces minimal uncertainty into the sign of projected changes in tropical cyclone intensity and rainfall, which allows us to have confidence in projections from global models with parameterized convection and resolution fine enough to include tropical cyclones.


Asunto(s)
Tormentas Ciclónicas/estadística & datos numéricos , Calentamiento Global/estadística & datos numéricos , Actividades Humanas/estadística & datos numéricos , Clima Tropical , Simulación por Computador , Actividades Humanas/tendencias , Probabilidad , Lluvia , Incertidumbre , Viento
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