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1.
Sci Total Environ ; 855: 158829, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36116637

RESUMO

The integration of life-history, physiological and behavioural traits into the pace-of-life generates a powerful framework to understand trait variation in nature both along environmental gradients and in response to environmental stressors. While the gut microbiome has been hypothesized as a candidate mechanism to underlie differentiation in the pace-of-life, this has been rarely studied. We investigated the role of the gut microbiome in contributing to the differentiation in pace-of-life and in thermal adaptation between populations of Ischnura elegans damselfly larvae inhabiting warmer low latitudes and colder high latitudes. We carried out a common-garden experiment, whereby we manipulated the exposure of the damselfly larvae to two key global warming factors: 4 °C warming and a 30 °C heat wave. Comparing the bacterial composition of the food source and the bacterioplankton indicated that damselfly larvae differentially take up bacteria from the surrounding environment and have a resident and functionally relevant microbiome. The gut microbiome differed between larvae of both latitudes, and this was associated with the host's latitudinal differentiation in activity, a key pace-of-life trait. Under heat wave exposure, the gut microbial community composition of high-latitude larvae converged towards that of the low-latitude larvae, with an increase in bacteria that likely are important in providing energy to cope with the heat wave. This suggests an adaptive latitude-specific shift in the gut microbiota matching the better ability of low-latitude hosts to deal with heat extremes. In general, our study provides evidence for the gut microbiome contributing to latitudinal differentiation in both the pace-of-life and in heat adaptation in natural populations.


Assuntos
Microbioma Gastrointestinal , Odonatos , Animais , Odonatos/fisiologia , Aquecimento Global , Larva , Temperatura Alta , Bactérias
2.
Sci Total Environ ; 855: 158800, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36116665

RESUMO

Fine root litter represents an important carbon input to soils, but the effect of global warming on fine root turnover (FRT) is hardly explored in forest ecosystems. Understanding tree fine roots' response to warming is crucial for predicting soil carbon dynamics and the functioning of forests as a sink for atmospheric carbon dioxide (CO2). We studied fine root production (FRP) with ingrowth cores and used radiocarbon signatures of first-order, second- to third-order, and bulk fine roots to estimate fine root turnover times after 8 and 14 years of soil warming (+4 °C) in a temperate forest. Fine root turnover times of the individual root fractions were estimated with a one-pool model. Soil warming strongly increased fine root production by up to 128 % within one year, but after two years, the production was less pronounced (+35 %). The first-year production was likely very high due to the rapid exploitation of the root-free ingrowth cores. The radiocarbon signatures of fine roots were overall variable among treatments and plots. Soil warming tended to decrease fine root turnover times of all the measured root fractions after 8 and 14 years of warming, and there was a tendency for trees to use older carbon reserves for fine root production in warmed plots. Furthermore, soil warming increased fine root turnover from 50 to 106 g C m-2 yr-1 (based on two different approaches). Our findings suggest that future climate warming may increase carbon input into soils by enhancing fine root turnover. If this increase may partly offset carbon losses by increased mineralization of soil organic matter in temperate forest soils is still unclear and should guide future research.


Assuntos
Ecossistema , Solo , Florestas , Árvores , Aquecimento Global , Dióxido de Carbono , Raízes de Plantas , Biomassa
3.
Sci Total Environ ; 857(Pt 1): 159311, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36216047

RESUMO

Composting is an effective alternative for recycling faecal sludge into organic fertilisers. A microflora-earthworm (Eisenia fetida) synergistic cooperation system was constructed to enhance the composting efficiency of faecal sludge. The impact of earthworms and carbon-rich wastes (rice straw (RS) and sawdust (S)) on compost properties, greenhouse gas emissions, and key microbial species of composting were evaluated. The addition of RS or S promoted earthworm growth and reproduction. The earthworm-based system reduced the volatile solid of the final substrate by 13.19-16.24 % and faecal Escherichia coli concentrations by 1.89-3.66 log10 cfu/g dry mass compared with the earthworm-free system. The earthworm-based system increased electrical conductivity by 0.322-1.402 mS/cm and reduced C/N by 56.16-64.73 %. The NH4+:NO3- ratio of the final faecal sludge and carbon-rich waste was <0.16. The seed germination index was higher than 80 %. These results indicate that earthworms contribute to faecal sludge maturation. Earthworm addition reduced CO2 production. The simultaneous addition of earthworms and RS system (FRS2) resulted in the lowest global warming potential (GWP). The microbial diversity increased significantly over time in the RS-only system, whereas it initially increased and later decreased in the FRS2 system. Cluster analysis revealed that earthworms had a more significant impact on the microbial community than the addition of carbon-rich waste. Co-occurrence networks for earthworm-based systems were simple than those for earthworm-free systems, but the major bacterial genera were more complicated. Highly abundant key species (norank_f_Chitinophagaceae and norank_f_Gemmatimonadaceae) are closely related. Microbes may be more cooperative than competitive, facilitating the conversion of carbon and nitrogen in earthworm-based systems. This work has demonstrated that using earthworms is an effective approach for promoting the efficiency of faecal sludge composting and reducing GWP.


Assuntos
Compostagem , Microbiota , Oligoquetos , Oryza , Animais , Esgotos/química , Carbono/análise , Aquecimento Global , Solo/química
4.
Sci Total Environ ; 857(Pt 1): 159332, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36228797

RESUMO

Global warming has brought extensive and far-reaching impacts on human life and production. A pumped hydro energy storage contributes to the large-scale development of renewable energy and serves as an important measure to mitigate climate change. Despite considerable efforts in estimating the potential of the pumped hydro energy storage, research gaps in response to global warming remain. In this regard, this study conducts a novel assessment of the pumped hydro energy storage's potential from a dynamic perspective, taking the Qinghai-Tibet Plateau as the study area. The spatiotemporal evolution of the pumped hydro energy storage's potential over the past few decades (the 1970s-2017) is analyzed, and its response to precipitation is identified innovatively. On this basis, the trend in the future period is further predicted for the first time, which is divided into near, short, medium, and long terms. Results show that the pumped hydro energy storage potential has a generally upward but not monotonic trend, decreasing from the 1970s to 1995 and then rising more dramatically, with slopes of 5548.5 ± 69.2 GWhyr-1 and -238.1 ± 90.4 GWhyr-1. In the majority (68.6 %) of lake basins (68.6 %), changes in precipitation positively contribute to the pumped hydro energy storage potential, resulting in a noticeable growth in the future. Under the representative concentration pathway of 8.5, the mean potential density is projected to rise by 23.4 %, 25.2 %, 28.3 %, and 30.6 % in the near, short, medium, and long terms, respectively. This result indicates that high-intensity greenhouse gas emissions under this scenario will lead to a greater potential for the pumped hydro energy storage in the future.


Assuntos
Mudança Climática , Aquecimento Global , Humanos , Tibet
5.
Sci Total Environ ; 856(Pt 1): 158903, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36419276

RESUMO

The increase in temperature due to global warming greatly affects the toxicity produced by pesticides in the aquatic ecosystem. Studies investigating the effects of such environmental stress factors on next generations are important in terms of the sustainability of ecosystems. In this study, the effects of parental synergistic exposure to glyphosate and temperature increase on the next generation were investigated in a zebrafish model. For this purpose, adult zebrafish were exposed to 1 ppm and 5 ppm glyphosate for 96 h at four different temperatures (28.5, 29.0, 29.5, 30.0 °C). At the end of this period, some of the fish were subjected to the recovery process for 10 days. At the end of both treatments, a new generation was taken from the fish and morphological, physiological, molecular and behavioral analysis were performed on the offspring. According to the results, in parallel with the 0.5-degree temperature increase applied to the parents with glyphosate exposure, lower survival rate, delay in hatching, increased body malformations and lower blood flow and heart rate were detected in the offspring. In addition, according to the results of whole mouth larva staining, increased apoptosis, free oxygen radical formation and lipid accumulation were detected in the offspring. Moreover, it has been observed that the temperature increases to which the parents are exposed affects the light signal transmission and serotonin pathways in the offspring, resulting in more dark/light locomotor activity and increased thigmotaxis.


Assuntos
Aquecimento Global , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Ecossistema , Glicina/toxicidade
6.
Sci Total Environ ; 856(Pt 2): 159201, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36202353

RESUMO

On the alpine areas such as Tianshan Mountains, snow and glaciers are widely distributed, which are sensitive to temperature changes. However, due to high altitude and scarcity of observed stations, the temperature changes and their causes in Tianshan are unclear. To address this issue, this study integrated Thiel-Sen trend test, Pearson correlation, and wavelet analysis methods to analyze the driving factors of temperature changes in Tianshan. We draw the following conclusions: (1) In the past 40 years, Tianshan warmed at a rate of 0.30 °C/decade. Seasonally, the temperature increased the most in spring and summer; spatially, the east Tianshan experienced the most warming. (2) Climate change has affected significant warming in the Tianshan. (3) The large-scale climate teleconnections found to be associated with warming in the Tianshan include North Pacific pattern, Atlantic Multidecadal Variability (AMV), North Atlantic Oscillation, and Western Hemisphere Warm Pool (WHWP). During the study period, the temperature changes lagged AMV and WHWP by 1.5 months, North Tropical Atlantic Index and Tropical Northern Atlantic Index by 3 months, and Arctic Oscillation by 4 months. This research contributes to understanding the response of dry mountains to global warming and atmospheric circulation changes.


Assuntos
Aquecimento Global , Camada de Gelo , Temperatura , Mudança Climática , Estações do Ano
7.
Sci Total Environ ; 856(Pt 2): 159222, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36209886

RESUMO

Humans have long dreamed of traveling to space. In response to the recent increase in commercial space flight, this paper evaluates environmental impacts of human space travel, both past and present, to shed light on the large environmental footprint of such activities. This environmental impact also has a moral component, since most of the global population will never be able to participate in such activities, yet still must bear the cost. Ironically, instead of a space future acting as a relief valve on Earth's resources, few activities exact a heavier burden on our planet's resources than the space pursuit, for the number of people it serves. This analysis utilized the structure of life cycle assessment. Data on launch vehicles mass and propellant type and mass was taken from public sources. Combustion emission results were calculated using combustion analysis software. These data were then combined with data from life cycle inventory databases and impact assessment methods to evaluate midpoint impact indicators. The hourly impact from sustaining humans in space over 1500 kg CO2-eq per hour. To put this into context, this is 2000 times greater than the emission rate of the average person on the globe, which we term global citizen equivalents (GCE). This global warming impact is also 650 times greater than the average person in the U.S. In terms of familiar activities, this is equivalent to continuously supplying at least 4 MW of electricity from the U.S. grid; simultaneously driving over sixty diesel buses; or occupying twenty seats on a Boeing 747 that never lands. Clearly such impacts raise questions not only to the sustainability of such activities, but also to the moral and ethical implications where such travel is limited to only the very wealthiest, but the costs are borne by all with few benefits to show from the endeavour.


Assuntos
Veículos Automotores , Voo Espacial , Humanos , Aquecimento Global , Meio Ambiente , Princípios Morais
9.
Nat Commun ; 13(1): 6893, 2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371500

RESUMO

Methane (CH4) emissions induced by Large Igneous Provinces have the potential to contribute to global environmental changes that triggered mass extinctions in Earth's history. Here, we explore the source of methane in gas samples from central Sichuan Basin, which is within the Emeishan Large Igneous Province (ELIP). We report evidence of high methane formation temperatures (between 249-17/+19 and 256-20/+22 °C) from clumped methane measurements and mantle-derived signatures of noble gases, which verify that oil-cracked CH4 and pyrobitumen are by-products within the reservoirs, associated with hydrothermal activity and enhanced heating by the ELIP. We estimate the volume of oil-cracked CH4 induced by the ELIP and argue that CH4 emissions would have been sufficient to initiate global warming prior to the end of the Permian. We also suggest that similar emissions from oil-cracked CH4 associated with the Siberian Traps Large Igneous Province may also have contributed to the end-Permian mass extinction significantly.


Assuntos
Extinção Biológica , Metano , Temperatura , Aquecimento Global
11.
Science ; 378(6619): 532-537, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36378957

RESUMO

Arctic fires can release large amounts of carbon from permafrost peatlands. Satellite observations reveal that fires burned ~4.7 million hectares in 2019 and 2020, accounting for 44% of the total burned area in the Siberian Arctic for the entire 1982-2020 period. The summer of 2020 was the warmest in four decades, with fires burning an unprecedentedly large area of carbon-rich soils. We show that factors of fire associated with temperature have increased in recent decades and identified a near-exponential relationship between these factors and annual burned area. Large fires in the Arctic are likely to recur with climatic warming before mid-century, because the temperature trend is reaching a threshold in which small increases in temperature are associated with exponential increases in the area burned.


Assuntos
Carbono , Aquecimento Global , Taiga , Incêndios Florestais , Regiões Árticas , Carbono/análise , Solo , Temperatura
12.
J Environ Manage ; 324: 116390, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36352713

RESUMO

This investigation explores whether sustainable finance and renewable energy could facilitate U.S. carbon neutrality. We perform the time-varying parameter-stochastic volatility-vector auto-regression (TVP-SV-VAR) model to obtain the changing relations among U.S. sustainable finance (SF), renewable energy (RE) and carbon dioxide emission (CO2). The empirical outcomes reveal a short-term negative effect from RE to CO2, indicating that renewable energy consumption could promote U.S. carbon neutrality. This effect is asymmetrical, and it could be observed that RE increase has a greater effect on CO2 than RE reduction. Also, the development of sustainable finance could facilitate U.S. carbon neutrality, and the direct impact is longer and more significant than RE, but the indirect effect of SF on CO2 by influencing RE is hysteretic. Besides, the asymmetric effect reveals that the negative direct impact of SF increase on CO2 is smaller than SF reduction, and the latter's indirect effect is more rapid than the former. Against the backdrop of global warming and frequent extreme weather, the above conclusions have meaningful practical applications for the U.S. to achieve carbon neutrality targets through developing sustainable finance and renewable energy.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Estados Unidos , Dióxido de Carbono/análise , Energia Renovável , Aquecimento Global , Condições Sociais
13.
Sci Rep ; 12(1): 20687, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36450837

RESUMO

Human-induced climate change has increased the frequency and intensity of heavy precipitation1. Due to the complexity of runoff generation and the streamflow process, the historical impact of human-induced climate change on river flooding remains uncertain. Here, we address the question of whether anthropogenic climate change has altered the probability of the extreme river flood events for the period 1951-2010 based on simulated river discharge derived from large ensemble climate experiments with and without human-induced climate change. The results indicate that human-induced climate change altered the probabilities of 20 of the 52 analyzed flood events. Fourteen of these 20 flood events, which occurred mainly in Asia and South America, were very likely to have been enhanced by human-induced climate change due to an increase in heavy precipitation. Conversely, two flood events in North/South America and two flood events in Asia and two flood events in Europe were suppressed by human-induced climate change, perhaps as a result of lower snowfall. Human-induced climate change has enhanced flooding more prominently in recent years, providing important insights into potential adaptation strategies for river flooding.


Assuntos
Inundações , Terapia Implosiva , Humanos , Aquecimento Global , Rios , Mudança Climática
14.
Sci Rep ; 12(1): 18839, 2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36336707

RESUMO

Antarctica is one of the most stressful environments for plant life and the Antarctic pearlwort (Colobanthus quitensis) is adapted to the hostile conditions. Plant-associated microorganisms can contribute to plant survival in cold environments, but scarce information is available on the taxonomic structure and functional roles of C. quitensis-associated microbial communities. This study aimed at evaluating the possible impacts of climate warming on the taxonomic structure of C. quitensis endophytes and at investigating the contribution of culturable bacterial endophytes to plant growth at low temperatures. The culture-independent analysis revealed changes in the taxonomic structure of bacterial and fungal communities according to plant growth conditions, such as the collection site and the presence of open-top chambers (OTCs), which can simulate global warming. Plants grown inside OTCs showed lower microbial richness and higher relative abundances of biomarker bacterial genera (Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, Aeromicrobium, Aureimonas, Hymenobacter, Novosphingobium, Pedobacter, Pseudomonas and Sphingomonas) and fungal genera (Alternaria, Cistella, and Vishniacozyma) compared to plants collected from open areas (OA), as a possible response to global warming simulated by OTCs. Culturable psychrotolerant bacteria of C. quitensis were able to endophytically colonize tomato seedlings and promote shoot growth at low temperatures, suggesting their potential contribution to plant tolerance to cold conditions.


Assuntos
Aquecimento Global , Micobioma , Temperatura , Regiões Antárticas , Bactérias/genética , Folhas de Planta , Plantas
16.
Sci Rep ; 12(1): 17693, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271134

RESUMO

Geological records of ice sheet collapse can provide perspective on the ongoing retreat of grounded and floating ice. An abrupt retreat of the West Antarctic Ice Sheet (WAIS) that occurred during the early deglaciation is well recorded on the eastern Ross Sea continental shelf. There, an ice shelf breakup at 12.3 ± 0.6 cal. (calibrated) kyr BP caused accelerated ice-mass loss from the Bindschadler Ice Stream (BIS). The accelerated mass loss led to a significant negative mass balance that re-organized WAIS flow across the central and eastern Ross Sea. By ~ 11.5 ± 0.3 cal kyr BP, dynamic thinning of grounded ice triggered a retreat that opened a ~ 200-km grounding-line embayment on the Whales Deep Basin (WDB) middle continental shelf. Here, we reconstruct the pattern, duration and rate of retreat from a backstepping succession of small-scale grounding-zone ridges that formed on the embayment's eastern flank. We used two end-member paleo-sediment fluxes, i.e., accumulation rates, to convert the cumulative sediment volumes of the ridge field to elapsed time for measured distances of grounding-line retreat. The end-members fluxes correspond to deposition rates for buttressed and unbuttressed ice stream flow. Both scenarios require sustained rapid retreat that exceeded several centuries. Grounding-line retreat is estimated to have averaged between ~ 100 ± 32 and ~ 700 ± 79 ma-1. The evidence favors the latter scenario because iceberg furrows that cross cut the ridges in deep water require weakly buttressed flow as the embayment opened. In comparison with the modern grounding-zone dynamics, this paleo-perspective provides confidence in model projections that a large-scale sustained contraction of grounded ice is underway in several Pacific-Ocean sectors of the WAIS.


Assuntos
Aquecimento Global , Camada de Gelo , Regiões Antárticas , Água , Oceano Pacífico
17.
West Afr J Med ; 39(10): 991-992, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36259666
19.
J Anim Ecol ; 91(10): 1944-1947, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36193670

RESUMO

Research Highlight: Réveillon, T., Rota, T., Chauvet, É., Lecerf, A., & Sentis, A. (2022). Energetic mismatch induced by warming decreases leaf litter decomposition by aquatic detritivores. Journal of Animal Ecology, https://doi.org/10.1111/1365-2656.13710. Global change holds complex consequences for Earth's ecosystems, with global warming simultaneously affecting multiple aspects including individual physiology, population dynamics and ecosystem processes. In a recent study on stream decomposition under global warming, Réveillon, et al. (2022) combined individual-level laboratory assessments of metabolic rates and leaf-litter ingestion with experimentally parameterized consumer-resource models, designed to reveal how stream-detritivore populations respond to combined impacts of warming and declining body size. Their findings of reduced energetic efficiency, weakened detritivore populations and reduced decomposition in warmed streams expand our understanding of how global change mechanistically links changes from the individual to the ecosystem level.


Assuntos
Ecossistema , Rios , Animais , Aquecimento Global , Temperatura Alta , Folhas de Planta
20.
Nature ; 611(7934): 93-98, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36289332

RESUMO

Temperature affects the rate of all biochemical processes in ectotherms1,2 and is therefore critical for determining their current and future distribution under global climate change3-5. Here we show that the rate of biological processes maintaining growth, homeostasis and ageing in the permissive temperature range increases by 7% per degree Celsius (median activation energy Ea = 0.48 eV from 1,351 rates across 314 species). By contrast, the processes underlying heat failure rate within the stressful temperature range are extremely temperature sensitive, such that heat failure increases by more than 100% per degree Celsius across a broad range of taxa (median Ea = 6.13 eV from 123 rates across 112 species). The extreme thermal sensitivity of heat failure rates implies that the projected increase in the frequency and intensity of heatwaves can exacerbate heat mortality for many ectothermic species with severe and disproportionate consequences. Combining the extreme thermal sensitivities with projected increases in maximum temperatures globally6, we predict that moderate warming scenarios can increase heat failure rates by 774% (terrestrial) and 180% (aquatic) by 2100. This finding suggests that we are likely to underestimate the potential impact of even a modest global warming scenario.


Assuntos
Regulação da Temperatura Corporal , Clima Quente Extremo , Aquecimento Global , Temperatura Alta , Aquecimento Global/mortalidade , Temperatura Alta/efeitos adversos , Envelhecimento , Crescimento , Homeostase , Animais
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