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1.
Glob Chang Biol ; 30(4): e17281, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38619550

RESUMEN

The ongoing climate change on the Tibetan Plateau, leading to warming and precipitation anomalies, modifies phosphorus (P) cycling in alpine meadow soils. However, the interactions and cascading effects of warming and precipitation changes on the key "extracellular" and "intracellular" P cycling genes (PCGs) of bacteria are largely unknown for these P-limited ecosystems. We used metagenomics to analyze the individual and combined effects of warming and altered precipitation on soil PCGs and P transformation in a manipulation experiment. Warming and increased precipitation raised Olsen-P (bioavailable P, AP) by 13% and 20%, respectively, mainly caused by augmented hydrolysis of organic P compounds (NaOH-Po). The decreased precipitation reduced soil AP by 5.3%. The richness and abundance of the PCGs' community in soils on the cold Tibetan plateau were more sensitive to warming than altered precipitation. The abundance of PCGs and P cycling processes decreased under the influence of individual climate change factors (i.e., warming and altered precipitation alone), except for the warming combined with increased precipitation. Pyruvate metabolism, phosphotransferase system, oxidative phosphorylation, and purine metabolism (all "intracellular" PCG) were closely correlated with P pools under climate change conditions. Specifically, warming recruited bacteria with the phoD and phoX genes, which encode enzymes responsible for phosphoester hydrolysis (extracellular P cycling), strongly accelerated organic P mineralization and so, directly impacted P bioavailability in alpine soil. The interactions between warming and altered precipitation profoundly influenced the PCGs' community and facilitated microbial adaptation to these environmental changes. Warming combined with increased precipitation compensated for the detrimental impacts of the individual climate change factors on PCGs. In conclusion, warming combined with rising precipitation has boosting effect on most P-related functions, leading to the acceleration of P cycling within microbial cells and extracellularly, including mineralization and more available P release for microorganisms and plants in alpine soils.


Asunto(s)
Ecosistema , Suelo , Humanos , Disponibilidad Biológica , Cambio Climático , Fósforo
2.
J Emerg Manag ; 22(7): 63-69, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38573730

RESUMEN

Until the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, developing countries, especially countries in the African continent, battled with the impact of climate change on the food value-chain systems and general livelihood. In this study, we discuss climate change concerns post-COVID-19 and argue that the outbreak of the COVID-19 pandemic has exacerbated the vulnerabilities of most developing and emerging economies. This has heightened political tensions and unrest among such developing nations. We suggest enhancement and intensification of efficient and effective locally engineered adaptation strategies in the post-COVID-19 era for countries that have been susceptible to the impact of climate change and other recent shocks.


Asunto(s)
COVID-19 , Humanos , Cambio Climático , Pandemias , Brotes de Enfermedades
3.
Philos Trans R Soc Lond B Biol Sci ; 379(1902): 20230011, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38583474

RESUMEN

Most emissions scenarios suggest temperature and precipitation regimes will change dramatically across the globe over the next 500 years. These changes will have large impacts on the biosphere, with species forced to migrate to follow their preferred environmental conditions, therefore moving and fragmenting ecosystems. However, most projections of the impacts of climate change only reach 2100, limiting our understanding of the temporal scope of climate impacts, and potentially impeding suitable adaptive action. To address this data gap, we model future climate change every 20 years from 2000 to 2500 CE, under different CO2 emissions scenarios, using a general circulation model. We then apply a biome model to these modelled climate futures, to investigate shifts in climatic forcing on vegetation worldwide, the feasibility of the migration required to enact these modelled vegetation changes, and potential overlap with human land use based on modern-day anthromes. Under a business-as-usual scenario, up to 40% of terrestrial area is expected to be suited to a different biome by 2500. Cold-adapted biomes, particularly boreal forest and dry tundra, are predicted to experience the greatest losses of suitable area. Without mitigation, these changes could have severe consequences both for global biodiversity and the provision of ecosystem services. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.


Asunto(s)
Biodiversidad , Ecosistema , Humanos , Tundra , Cambio Climático , Temperatura
4.
Sci Rep ; 14(1): 8028, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38580811

RESUMEN

Agroforestry is a management strategy for mitigating the negative impacts of climate and adapting to sustainable farming systems. The successful implementation of agroforestry strategies requires that climate risks are appropriately assessed. The spatial scale, a critical determinant influencing climate impact assessments and, subsequently, agroforestry strategies, has been an overlooked dimension in the literature. In this study, climate risk impacts on robusta coffee production were investigated at different spatial scales in coffee-based agroforestry systems across India. Data from 314 coffee farms distributed across the districts of Chikmagalur and Coorg (Karnataka state) and Wayanad (Kerala state) were collected during the 2015/2016 to 2017/2018 coffee seasons and were used to quantify the key climate drivers of coffee yield. Projected climate data for two scenarios of change in global climate corresponding to (1) current baseline conditions (1985-2015) and (2) global mean temperatures 2 °C above preindustrial levels were then used to assess impacts on robusta coffee yield. Results indicated that at the district scale rainfall variability predominantly constrained coffee productivity, while at a broader regional scale, maximum temperature was the most important factor. Under a 2 °C global warming scenario relative to the baseline (1985-2015) climatic conditions, the changes in coffee yield exhibited spatial-scale dependent disparities. Whilst modest increases in yield (up to 5%) were projected from district-scale models, at the regional scale, reductions in coffee yield by 10-20% on average were found. These divergent impacts of climate risks underscore the imperative for coffee-based agroforestry systems to develop strategies that operate effectively at various scales to ensure better resilience to the changing climate.


Asunto(s)
Coffea , Café , India , Agricultura , Granjas , Cambio Climático
5.
J Phycol ; 60(2): 503-516, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38426571

RESUMEN

Kelps are in global decline due to climate change, which includes ocean warming. To identify vulnerable species, we need to identify their tolerances to increasing temperatures and determine whether tolerances are altered by co-occurring drivers such as inorganic nutrient levels. This is particularly important for those species with restricted distributions, which may already be experiencing thermal stress. To identify thermal tolerance of the range-restricted kelp Lessonia corrugata, we conducted a laboratory experiment on juvenile sporophytes to measure performance (growth, photosynthesis) across its thermal range (4-22°C). We determined the upper thermal limit for growth and photosynthesis to be ~22-23°C, with a thermal optimum of ~16°C. To determine if elevated inorganic nitrogen availability could enhance thermal tolerance, we compared the performance of juveniles under low (4.5 µmol · d-1) and high (90 µmol · d-1) nitrate conditions at and above the thermal optimum (16-23.5°C). Nitrate enrichment did not enhance thermal performance at temperatures above the optimum but did lead to elevated growth rates at the thermal optimum. Our results indicate L. corrugata is likely to be extremely susceptible to moderate ocean warming and marine heatwaves. Peak sea surface temperatures during summer in eastern and northeastern Tasmania can reach up to 20-21°C, and climate projections suggest that L. corrugata's thermal limit will be regularly exceeded by 2050 as southeastern Australia is a global ocean-warming hotspot. By identifying the upper thermal limit of L. corrugata, we have taken a critical step in predicting the future of the species in a warming climate.


Asunto(s)
Kelp , Nitratos , Cambio Climático , Temperatura , Océanos y Mares , Ecosistema
6.
Proc Natl Acad Sci U S A ; 121(11): e2303366121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38437536

RESUMEN

Phytoplankton and sea ice algae are traditionally considered to be the main primary producers in the Arctic Ocean. In this Perspective, we explore the importance of benthic primary producers (BPPs) encompassing microalgae, macroalgae, and seagrasses, which represent a poorly quantified source of Arctic marine primary production. Despite scarce observations, models predict that BPPs are widespread, colonizing ~3 million km2 of the extensive Arctic coastal and shelf seas. Using a synthesis of published data and a novel model, we estimate that BPPs currently contribute ~77 Tg C y-1 of primary production to the Arctic, equivalent to ~20 to 35% of annual phytoplankton production. Macroalgae contribute ~43 Tg C y-1, seagrasses contribute ~23 Tg C y-1, and microalgae-dominated shelf habitats contribute ~11 to 16 Tg C y-1. Since 2003, the Arctic seafloor area exposed to sunlight has increased by ~47,000 km2 y-1, expanding the realm of BPPs in a warming Arctic. Increased macrophyte abundance and productivity is expected along Arctic coastlines with continued ocean warming and sea ice loss. However, microalgal benthic primary production has increased in only a few shelf regions despite substantial sea ice loss over the past 20 y, as higher solar irradiance in the ice-free ocean is counterbalanced by reduced water transparency. This suggests complex impacts of climate change on Arctic light availability and marine primary production. Despite significant knowledge gaps on Arctic BPPs, their widespread presence and obvious contribution to coastal and shelf ecosystem production call for further investigation and for their inclusion in Arctic ecosystem models and carbon budgets.


Asunto(s)
Microalgas , Algas Marinas , Ecosistema , Presupuestos , Carbono , Cambio Climático , Cubierta de Hielo , Fitoplancton
8.
BMC Med ; 22(1): 131, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38519952

RESUMEN

BACKGROUND: Pandemics and climate change each challenge health systems through increasing numbers and new types of patients. To adapt to these challenges, leading health systems have embraced a Learning Health System (LHS) approach, aiming to increase the efficiency with which data is translated into actionable knowledge. This rapid review sought to determine how these health systems have used LHS frameworks to both address the challenges posed by the COVID-19 pandemic and climate change, and to prepare for future disturbances, and thus transition towards the LHS2.0. METHODS: Three databases (Embase, Scopus, and PubMed) were searched for peer-reviewed literature published in English in the five years to March 2023. Publications were included if they described a real-world LHS's response to one or more of the following: the COVID-19 pandemic, future pandemics, current climate events, future climate change events. Data were extracted and thematically analyzed using the five dimensions of the Institute of Medicine/Zurynski-Braithwaite's LHS framework: Science and Informatics, Patient-Clinician Partnerships, Continuous Learning Culture, Incentives, and Structure and Governance. RESULTS: The search yielded 182 unique publications, four of which reported on LHSs and climate change. Backward citation tracking yielded 13 additional pandemic-related publications. None of the climate change-related papers met the inclusion criteria. Thirty-two publications were included after full-text review. Most were case studies (n = 12, 38%), narrative descriptions (n = 9, 28%) or empirical studies (n = 9, 28%). Science and Informatics (n = 31, 97%), Continuous Learning Culture (n = 26, 81%), Structure and Governance (n = 23, 72%) were the most frequently discussed LHS dimensions. Incentives (n = 21, 66%) and Patient-Clinician Partnerships (n = 18, 56%) received less attention. Twenty-nine papers (91%) discussed benefits or opportunities created by pandemics to furthering the development of an LHS, compared to 22 papers (69%) that discussed challenges. CONCLUSIONS: An LHS 2.0 approach appears well-suited to responding to the rapidly changing and uncertain conditions of a pandemic, and, by extension, to preparing health systems for the effects of climate change. LHSs that embrace a continuous learning culture can inform patient care, public policy, and public messaging, and those that wisely use IT systems for decision-making can more readily enact surveillance systems for future pandemics and climate change-related events. TRIAL REGISTRATION: PROSPERO pre-registration: CRD42023408896.


Asunto(s)
COVID-19 , Aprendizaje del Sistema de Salud , Estados Unidos , Humanos , Pandemias , Cambio Climático , COVID-19/epidemiología , Atención al Paciente
9.
Conserv Biol ; : e14246, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38445689

RESUMEN

Climate refugia, areas where climate is expected to remain relatively stable, can offer a near-term safe haven for species sensitive to warming temperatures and drought. Understanding the influence of temperature, moisture, and disturbance on sensitive species is critical during this time of rapid climate change. Coastal habitats can serve as important refugia. Many of these areas consist of working forestlands, and there is a growing recognition that conservation efforts worldwide must consider the habitat value of working lands, in addition to protected areas, to effectively manage large landscapes that support biodiversity. The sensitivity of forest bats to climate and habitat disturbance makes them a useful indicator taxon. We tested how microclimate and forest management influence habitat use for 13 species of insectivorous bats in a large climate refugium in a global biodiversity hotspot. We examined whether bat activity during the summer dry season is greater in forests where coastal fog provides moisture and more stable temperatures across both protected mature stands and those regularly logged. Acoustic monitoring was conducted at a landscape scale with 20 study sites, and generalized linear mixed models were used to examine the influence of habitat variables. Six species were positively associated with warmer nighttime temperature, and 5 species had a negative relationship with humidity or a positive relationship with climatic moisture deficit. Our results suggest that these mammals may have greater climate adaptive capacity than expected, and, for now, that habitat use may be more related to optimal foraging conditions than to avoidance of warming temperatures and drought. We also determined that 12 of the 13 regionally present bat species were regularly detected in commercial timberland stands. Because forest bats are highly mobile, forage over long distances, and frequently change roosts, the stewardship of working forests must be addressed to protect these species.


Influencia del microclima y el manejo forestal sobre especies de murciélagos ante el cambio global Resumen Los refugios climáticos, áreas en donde se espera que el clima permanezca relativamente estable, pueden ofrecer un santuario a corto plazo para las especies sensibles al aumento de temperaturas y la sequía. Es muy importante entender la influencia de la temperatura, la humedad y las perturbaciones sobre las especies sensibles durante estos tiempos de cambio climático repentino. Los hábitats costeros pueden funcionar como refugios importantes. Muchas de estas áreas consisten en bosques funcionales y cada vez hay más reconocimiento de que los esfuerzos mundiales de conservación deben considerar el valor del hábitat de los suelos funcionales, además de las áreas protegidas, para manejar de manera efectiva los extensos paisajes que mantienen a la biodiversidad. La sensibilidad de los murciélagos de los bosques ante las perturbaciones climáticas y de hábitat hace que sean un taxón indicador útil. Analizamos cómo los microclimas y el manejo forestal influyen sobre el uso de hábitat de 13 especies de murciélagos insectívoros en un refugio climático amplio dentro de un punto caliente de biodiversidad mundial. Examinamos si la actividad de los murciélagos durante la temporada seca de verano es mayor en los bosques en donde la niebla costera proporciona humedad y temperaturas más estables tanto en los árboles maduros como aquellos que son talados con regularidad. Realizamos el monitoreo acústico a escala de paisaje en 20 estudios de sitio y usamos modelos lineales mixtos generalizados para examinar la influencia de las variables del hábitat. Seis especies estuvieron asociadas positivamente con la temperatura nocturna más cálida y cinco especies tuvieron una relación negativa con la humedad o una relación positiva con el déficit climático de humedad. Nuestros resultados sugieren que estos mamíferos pueden tener una mayor capacidad de adaptación climática de lo que se pensaba y, por ahora, que el uso de hábitat puede estar más relacionado con las condiciones óptimas de forrajeo que con la evasión de las temperaturas elevadas y la sequía. También determinamos que 12 de las 13 especies con presencia regional fueron detectadas con regularidad en los puntos de tala comercial. Ya que los murciélagos del bosque tienden a moverse mucho, forrajear a lo largo de grandes distancias y con frecuencia cambiar de nido, debemos abordar la administración de los bosques funcionales para proteger a estas especies.

10.
J Med Internet Res ; 26: e42140, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319701

RESUMEN

BACKGROUND: Health care providers worldwide are rapidly adopting electronic medical record (EMR) systems, replacing paper record-keeping systems. Despite numerous benefits to EMRs, the environmental emissions associated with medical record-keeping are unknown. Given the need for urgent climate action, understanding the carbon footprint of EMRs will assist in decarbonizing their adoption and use. OBJECTIVE: We aimed to estimate and compare the environmental emissions associated with paper medical record-keeping and its replacement EMR system at a high-volume eye care facility in southern India. METHODS: We conducted the life cycle assessment methodology per the ISO (International Organization for Standardization) 14040 standard, with primary data supplied by the eye care facility. Data on the paper record-keeping system include the production, use, and disposal of paper and writing utensils in 2016. The EMR system was adopted at this location in 2018. Data on the EMR system include the allocated production and disposal of capital equipment (such as computers and routers); the production, use, and disposal of consumable goods like paper and writing utensils; and the electricity required to run the EMR system. We excluded built infrastructure and cooling loads (eg. buildings and ventilation) from both systems. We used sensitivity analyses to model the effects of practice variation and data uncertainty and Monte Carlo assessments to statistically compare the 2 systems, with and without renewable electricity sources. RESULTS: This location's EMR system was found to emit substantially more greenhouse gases (GHGs) than their paper medical record system (195,000 kg carbon dioxide equivalents [CO2e] per year or 0.361 kg CO2e per patient visit compared with 20,800 kg CO2e per year or 0.037 kg CO2e per patient). However, sensitivity analyses show that the effect of electricity sources is a major factor in determining which record-keeping system emits fewer GHGs. If the study hospital sourced all electricity from renewable sources such as solar or wind power rather than the Indian electric grid, their EMR emissions would drop to 24,900 kg CO2e (0.046 kg CO2e per patient), a level comparable to the paper record-keeping system. Energy-efficient EMR equipment (such as computers and monitors) is the next largest factor impacting emissions, followed by equipment life spans. Multimedia Appendix 1 includes other emissions impact categories. CONCLUSIONS: The climate-changing emissions associated with an EMR system are heavily dependent on the sources of electricity. With a decarbonized electricity source, the EMR system's GHG emissions are on par with paper medical record-keeping, and decarbonized grids would likely have a much broader benefit to society. Though we found that the EMR system produced more emissions than a paper record-keeping system, this study does not account for potential expanded environmental gains from EMRs, including expanding access to care while reducing patient travel and operational efficiencies that can reduce unnecessary or redundant care.


Asunto(s)
Huella de Carbono , Registros Electrónicos de Salud , Hospitales Especializados , Registros Médicos , Papel , Clima , Programas Informáticos , Ambiente , India , Oftalmología , Sector de Atención de Salud , Cambio Climático
11.
Ann Glob Health ; 90(1): 15, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38370864

RESUMEN

Background: Health National Adaptation Plans were developed to increase the capacity of low- and middle-income countries (LMICs) to adapt to the impacts of climate change on the health sector. Climate and its health impacts vary locally, yet frameworks for evaluating the adaptive capacity of health systems on the subnational scale are lacking. In Kenya, counties prepare county integrated development plans (CIDPs), which contain information that might support evaluations of the extent to which counties are planning climate change adaptation for health. Objectives: To develop and apply a framework for evaluating CIDPs to assess the extent to which Kenya's counties are addressing the health sector's adaptive capacity to climate change. Methods: CIDPs were analyzed based on the extent to which they addressed climate change in their description of county health status, whether health is noted in their descriptions of climate change, and whether they mention plans for developing climate and health programs. Based on these and other data points, composite climate and health adaptation (CHA) scores were calculated. Associations between CHA scores and poverty rates were analyzed. Findings: CHA scores varied widely and were not associated with county-level poverty. Nearly all CIDPs noted climate change, approximately half mentioned health in the context of climate change and only 16 (34%) noted one or more specific climate-sensitive health conditions. Twelve (25%) had plans for a sub-program in both adaptive capacity and environmental health. Among the 24 counties with plans to develop climate-related programs in health programs, all specified capacity building, and 20% specified integrating health into disaster risk reduction. Conclusion: Analyses of county planning documents provide insights into the extent to which the impacts of climate change on health are being addressed at the subnational level in Kenya. This approach may support governments elsewhere in evaluating climate change adaptation for health by subnational governments.


Asunto(s)
Cambio Climático , Desastres , Humanos , Kenia , Promoción de la Salud , Planificación Social
12.
Sci Total Environ ; 920: 170944, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38360325

RESUMEN

BACKGROUND: Children are more vulnerable than adults to climate-related health threats, but reviews examining how climate change affects human health have been mainly descriptive and lack an assessment of the magnitude of health effects children face. This is the first systematic review and meta-analysis that identifies which climate-health relationships pose the greatest threats to children. OBJECTIVES: We reviewed epidemiologic studies to analyse various child health outcomes due to climate change and identify the relationships with the largest effect size. We identify population-specific risks and provide recommendations for future research. METHODS: We searched four large online databases for observational studies published up to 5 January 2023 following PRISMA (systematic review) guidelines. We evaluated each included study individually and aggregated relevant quantitative data. We used quantitative data in our meta-analysis, where we standardised effect sizes and compared them among different groupings of climate variables and health outcomes. RESULTS: Of 1301 articles we identified, 163 studies were eligible for analysis. We identified many relationships between climate change and child health, the strongest of which was increasing risk (60 % on average) of preterm birth from exposure to temperature extremes. Respiratory disease, mortality, and morbidity, among others, were also influenced by climate changes. The effects of different air pollutants on health outcomes were considerably smaller compared to temperature effects, but with most (16/20 = 80 %) pollutant studies indicating at least a weak effect. Most studies occurred in high-income regions, but we found no geographical clustering according to health outcome, climate variable, or magnitude of risk. The following factors were protective of climate-related child-health threats: (i) economic stability and strength, (ii) access to quality healthcare, (iii) adequate infrastructure, and (iv) food security. Threats to these services vary by local geographical, climate, and socio-economic conditions. Children will have increased prevalence of disease due to anthropogenic climate change, and our quantification of the impact of various aspects of climate change on child health can contribute to the planning of mitigation that will improve the health of current and future generations.


Asunto(s)
Contaminación del Aire , Salud Infantil , Cambio Climático , Niño , Humanos , Contaminación del Aire/efectos adversos
13.
Sci Total Environ ; 922: 171103, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38402970

RESUMEN

Temperature changes due to climate change and microplastic contamination are worldwide concerns, creating various problems in the marine environment. Therefore, this study was carried out to discover the impact of different temperatures of seawater exposed to different types of plastic materials on culture dependent bacterial responses and oxidative characteristics. Seawater was exposed to microplastics obtained from various plastic materials at different temperature (-18, +4, +20, and +35 °C) for seven days. Then microplastics were removed from the suspension and microplastic-exposed seawater samples were analyzed for bacterial activity, biofilm formation and oxidative characteristics (antioxidant, catalase, glutathione, and superoxide dismutase) using Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus. The results showed that the activity and biofilm formation of Pseudomonas aeruginosa and Staphylococcus aureus were affected through oxidative stress by catalase, glutathione, and superoxide dismutase due to the microplastic deformation by temperature changes. This study confirms that temperature changes as a result of climate change might influence microplastic degradation and their contamination impact in seawater in terms of bacterial metabolic and oxidation reactions.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Plásticos/análisis , Catalasa/metabolismo , Cambio Climático , Contaminantes Químicos del Agua/análisis , Agua de Mar/análisis , Estrés Oxidativo , Glutatión/metabolismo , Superóxido Dismutasa/metabolismo , Biopelículas
14.
Curr Biol ; 34(6): 1161-1167.e3, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38325374

RESUMEN

Wood growth is key to understanding the feedback of forest ecosystems to the ongoing climate warming. An increase in spatial synchrony (i.e., coincident changes in distant populations) of spring phenology is one of the most prominent climate responses of forest trees. However, whether temperature variability contributes to an increase in the spatial synchrony of spring phenology and its underlying mechanisms remains largely unknown. Here, we analyzed an extensive dataset of xylem phenology observations of 20 conifer species from 75 sites over the Northern Hemisphere. Along the gradient of increase in temperature variability in the 75 sites, we observed a convergence in the onset of cell enlargement roughly toward the 5th of June, with a convergence in the onset of cell wall thickening toward the summer solstice. The increase in rainfall since the 5th of June is favorable for cell division and expansion, and as the most hours of sunlight are received around the summer solstice, it allows the optimization of carbon assimilation for cell wall thickening. Hence, the convergences can be considered as the result of matching xylem phenological activities to favorable conditions in regions with high temperature variability. Yet, forest trees relying on such consistent seasonal cues for xylem growth could constrain their ability to respond to climate warming, with consequences for the potential growing season length and, ultimately, forest productivity and survival in the future.


Asunto(s)
Tracheophyta , Temperatura , Ecosistema , Cambio Climático , Xilema , Estaciones del Año , Árboles
15.
Environ Monit Assess ; 196(3): 299, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38396046

RESUMEN

Climate change is one of the greatest threats recently, of which developing countries are facing most of the brunt. In the fight against climate change, forests can play an important role, since they hold a substantial amount of terrestrial carbon and can therefore affect the global carbon cycle. Deforestation, however, is a significant challenge. There are financial incentives that can help in halting deforestation by compensating developing countries for their efforts. They require however assessments which makes it essential for developing countries to regularly monitor their stocking. Based on the aforementioned, forest carbon stock assessment was conducted in Margalla Hills National Park i.e., Sub-tropical Chir Pine Forest (SCPF) and Sub-tropical Broadleaved Evergreen Forest (SBEF), in Pakistan combining field inventory with a remote-sensing-based approach using machine learning algorithms. Circular plots of a 20 m radius were used for recording the data and Sentinel-2 (S2) and Sentinel-1 (S1) satellite data were used for estimating the Aboveground Biomass (AGB). The performances of Random Forests (RF) and Support Vector Machine (SVM) were explored. The AGB was higher for the SCPF. The RF performed better for SCPF, but SVM was better for SBEF. The free available satellite data in the form of S2 and S1 data offers an advantage for AGB estimations. The combination of S2 and S1 for future AGB studies in Pakistan is also recommended.


Asunto(s)
Monitoreo del Ambiente , Pinus , Biomasa , Algoritmos , Cambio Climático , Carbono
16.
PLoS One ; 19(2): e0299111, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38421994

RESUMEN

Global interpolated climate products are widely used in ecological research to investigate biosphere-climate interactions and to track ecological response to climate variability and climate change. In turn, biological data could also be used for an independent validation of one aspect of climate data quality. All else being equal, more variance explained in biological data identifies the better climate data product. Here, we compare seven global precipitation time series products, including gauge-based datasets (CRU-TS, UDEL-TS, GPCC), re-analysis products (ERA5, CHELSA), a satellite-based dataset (PERSIANN) and a multi-source product that draws on gauge, re-analysis, and satellite data (MSWEP). We focus on precipitation variables, because they are more difficult to interpolate than temperature, and show larger divergence among gridded data products. Our validation is based on 20 years of remotely sensed vegetation greenness (MODIS-EVI) and 120 years of tree ring records from the International Tree Ring Data Bank (ITRDB). The results for the 20-year EVI based validation shows that all gauge and re-analysis data products performed similarly, but were outperformed by the multi-source MSWEP product, especially in regions with low weather station coverage, such as Africa. For analyzing long 120-year time-series, UDEL-TS showed superior performance prior to the 1940s, with especially large margins for northern Asia and the Himalayas region. For other regions, CRU-TS and GPCC could be recommended. We provide maps that can guide the best regional choice of climate product for research involving time series of biological response to historic climate variability and climate change.


Asunto(s)
Cambio Climático , Polímeros , Sulfonas , Árboles , Factores de Tiempo , África
17.
Sci Rep ; 14(1): 3659, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38351076

RESUMEN

Temperature is a major ecological driver of mosquito-borne diseases as it influences the life-history of both the mosquito and the pathogen harboured within it. Understanding the mosquitoes' thermal biology is essential to inform risk prediction models of such diseases. Mosquitoes can respond to temperatures by microhabitat selection through thermal preference. However, it has not yet been considered that mosquitoes are likely to adapt to changing temperatures, for example during climate change, and alter their preference over evolutionary time. We investigated this by rearing six cohorts of the yellow fever mosquito Aedes aegypti at two temperatures (24 °C, 30 °C) for 20 generations and used these cohorts to explicitly separate the effects of long-term evolution and within-generation acclimation on their thermal preferences in a thermal gradient of 20-35 °C. We found that warm-evolved mosquitoes spent 31.5% less time at high temperatures, which affects their efficiency as a vector. This study reveals the complex interplay of experimental evolution, rearing temperatures, and thermal preference in Ae. aegypti mosquitoes. It highlights the significance of incorporating mosquito microhabitat selection in disease transmission models, especially in the context of climate change.


Asunto(s)
Aedes , Fiebre Amarilla , Animales , Temperatura , Mosquitos Vectores , Aedes/fisiología , Cambio Climático
18.
Nat Commun ; 15(1): 947, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38351211

RESUMEN

Declining Arctic sea ice is increasing polar bear land use. Polar bears on land are thought to minimize activity to conserve energy. Here, we measure the daily energy expenditure (DEE), diet, behavior, movement, and body composition changes of 20 different polar bears on land over 19-23 days from August to September (2019-2022) in Manitoba, Canada. Polar bears on land exhibited a 5.2-fold range in DEE and 19-fold range in activity, from hibernation-like DEEs to levels approaching active bears on the sea ice, including three individuals that made energetically demanding swims totaling 54-175 km. Bears consumed berries, vegetation, birds, bones, antlers, seal, and beluga. Beyond compensating for elevated DEE, there was little benefit from terrestrial foraging toward prolonging the predicted time to starvation, as 19 of 20 bears lost mass (0.4-1.7 kg•day-1). Although polar bears on land exhibit remarkable behavioral plasticity, our findings reinforce the risk of starvation, particularly in subadults, with forecasted increases in the onshore period.


Asunto(s)
Inanición , Ursidae , Humanos , Animales , Cambio Climático , Canadá , Dieta , Cubierta de Hielo , Regiones Árticas , Ecosistema
19.
Sci Total Environ ; 918: 170549, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38309335

RESUMEN

Vegetation is vital to the ecosystem, contributing to the global carbon balance, but susceptible to the impacts of climate change. Monitoring vegetation drought remains challenging due to the lack of widely accepted drought indices. This study focused on vegetation, and simulated the vegetation suitable water demand and soil available water supply (calculated by Remote-sensing-based Water Balance Assessment Tool model). The standardized Vegetation Water deficit Index (SVWDI) was established by calculating the vegetation water deficit, which reflects the response of vegetation to drought. We examined the spatiotemporal evolution of vegetation drought on the Loess Plateau and evaluated the applicability of standardized vegetation water deficit index. Our findings revealed that the standardized vegetation water deficit index demonstrated an overall upward trend across different time scales from 1991 to 2020. Drought conditions were concentrated in the first 20 years of the study period, but vegetation drought on the Loess Plateau has been alleviated in the past decade. Moreover, as the time scale extended, the trend of SVWDI generally decreased, with approximately 49.50 % (1-month scale), 46.66 % (3-month scale), 47.08 % (12-month scale), and 32.16 % (24-month scale) of the grid areas experiencing increased SVWDI. The correlation between SVWDI and tree-ring width index (TRWI) performed well under all precipitation gradients, but the Palmer drought severity index (PDSI) was only highly correlated with TRWI in regions with low precipitation. In terms of the relationship with vegetation health, SVWDI demonstrated the highest correlation with the normalized difference vegetation index (NDVI) across different time scales, followed by PDSI and standardized precipitation evapotranspiration index (SPEI). This study provides insights into the evolution of vegetation drought in response to climate change. The findings can guide initiatives such as returning farmland to forest and grassland on the Loess Plateau to aid climate change adaptation strategies.


Asunto(s)
Sequías , Ecosistema , Agua , Suelo , Bosques , Plantas , Árboles , Cambio Climático , China
20.
Glob Chang Biol ; 30(2): e17178, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38332577

RESUMEN

Climate change and anthropogenic stressors are redistributing species and altering community composition globally. Protected areas (PAs) may not sufficiently protect populations of species undergoing distributional shifts, necessitating that we evaluate existing PAs and identify areas for future protection to conserve biodiversity across regional and temporal scales. Coastal waterbirds are important indicators of marine ecosystem health, representing mobile, long-lived, higher trophic-level consumers. Using a 20-year citizen science dataset (1999-2019) with a before-after control-intervention sampling framework for habitat protection, we applied dynamic occupancy models to assess winter occupancy trends along the Pacific coast of Canada. Specifically, we sought to understand potential drivers of regional declines, spatial commonalities among guilds, and changes in habitat use before and after PA designation, as well as between PAs and non-PAs. Occupancy trends varied regionally, with greater declines in the south compared to the north. Regional differences underlined potential range shifts, particularly for species with traits linked to temperature tolerance, movement, and high productivity foraging, as cold-tolerant, migratory benthivores and piscivores wintered farther north relative to 20 years ago or retreated to cold-water fjords. While 21 of 57 (36.8%) species responded positively to PA designation (before-after), greater occupancy declines tended to occur in PAs established pre-1999 relative to non-PAs (control-intervention). Since PAs are currently concentrated in the south, negative associations were most apparent for species retreating northward, but existing PAs may have a stabilizing or transitory effect on southern wintering species shifting into the region from farther south. We emphasize that conservation strategies must balance persistence of current communities with preserving the climate-adapted biodiversity of tomorrow by accounting for community-level effects of species moving into and out of existing PAs. Incorporating range shifts into PA planning by predicting distributional changes will allow conservation practitioners to identify priority habitats, such as cold-water refugia, for persistent wildlife communities.


Le changement climatique et les facteurs de stress anthropiques redistribuent les espèces et modifient la composition des communautés à l'échelle mondiale. Les zones protégées (ZP) ne protègent peut-être pas suffisamment les populations d'espèces qui subissent des changements de répartition, ce qui nous oblige à évaluer les ZP existantes et à identifier les zones à protéger à l'avenir pour conserver la biodiversité à l'échelle régionale et temporelle. Les oiseaux côtiers sont des indicateurs importants de la santé des écosystèmes marins, car ils représentent des consommateurs mobiles, ont une longue durée de vie et représente le niveau trophique supérieur. En utilisant un ensemble de données de science participative sur 20 ans (1999-2019) avec un échantillonnage avant-après contrôle-intervention (AACI) pour la protection de l'habitat, nous avons appliqué des modèles d'occupation dynamiques pour évaluer les tendances de l'occupation hivernale le long de la côte pacifique du Canada. Plus précisément, nous avons cherché à comprendre les moteurs potentiels des déclins régionaux, les points communs spatiaux entre les guildes et les changements dans l'utilisation de l'habitat avant et après la désignation de le ZP, ainsi qu'entre les ZP et les non-ZP. Les tendances en matière d'occupation varient d'une région à l'autre, avec des déclins plus importants dans le sud que dans le nord. Les différences régionales soulignent les déplacements potentiels de l'aire de répartition, en particulier pour les espèces dont les caractéristiques sont liées à la tolérance à la température, aux déplacements et à la recherche de nourriture à rendement élevé, car les benthivores et les piscivores migrateurs tolérants au froid ont hiverné plus au nord qu'il y a 20 ans ou se sont retirés dans les fjords aux eaux froides. Alors que 21 des 57 (36,8 %) espèces ont réagi positivement à la désignation des aires protégées (avant-après), les baisses d'occupation ont eu tendance à être plus importantes dans les aires protégées créées avant 1999 que dans les aires non protégées (contrôle-intervention). Comme les aires protégées sont actuellement concentrées dans le sud, les associations négatives étaient plus évidentes pour les espèces qui se retirent vers le nord, mais les aires protégées existantes peuvent avoir un effet stabilisateur ou transitoire sur les espèces hivernant dans le sud qui se déplacent dans la région à partir d'une région plus au sud. Nous soulignons que les stratégies de conservation doivent trouver un équilibre entre la persistance des communautés actuelles et la préservation de la biodiversité adaptée au climat de demain, en tenant compte des effets au niveau des communautés des espèces qui entrent dans les aires protégées existantes ou qui en sortent. L'intégration des changements d'aire de répartition dans la planification des aires protégées en prédisant les changements de distribution permettra aux praticiens de la conservation d'identifier les habitats prioritaires, tels que les refuges d'eau froide, pour les communautés d'espèces sauvages persistantes.


Asunto(s)
Aves , Ecosistema , Animales , Conservación de los Recursos Naturales , Biodiversidad , Cambio Climático , Agua
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