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Climate change is an existential threat to the environmental and socioeconomic sustainability of the coastal zone and impacts will be complex and widespread. Evidence from California and across the United States shows that climate change is impacting coastal communities and challenging managers with a plethora of stressors already present. Widespread action could be taken that would sustain California's coastal ecosystems and communities. In this perspective, we highlight the main threat to coastal sustainability: the compound effects of episodic events amplified with ongoing climate change, which will present unprecedented challenges to the state. We present two key challenges for California's sustainability in the coastal zone: 1) accelerating sea-level rise combined with storm impacts, and 2) continued warming of the oceans and marine heatwaves. Cascading effects from these types of compounding events will occur within the context of an already stressed system that has experienced extensive alterations due to intensive development, resource extraction and harvesting, spatial containment, and other human use pressures. There are critical components that could be used to address these immediate concerns, including comanagement strategies that include diverse groups and organizations, strategic planning integrated across large areas, rapid implementation of solutions, and a cohesive and policy relevant research agenda for the California coast. Much of this has been started in the state, but the scale could be increased, and timelines accelerated. The ideas and information presented here are intended to help expand discussions to sharpen the focus on how to encourage sustainability of California's iconic coastal region.
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Coral reefs are experiencing severe decline, and urgent action is required at local and global scales to curb ecosystem loss. Establishing new regulations to protect corals, however, can be time consuming and costly, and it is therefore necessary to leverage existing legal instruments, such as policies originally designed to address terrestrial rather than marine activities, to prevent coral reef degradation. Focusing on the United States, but drawing on successful examples worldwide, we present actionable pathways to increase coral protections under legislation that was originally designed to advance clean freshwater, safe drinking water, and emergency management. We identify specific legal policies and procedures (e.g., industrial permit limits, nonpoint source management incentives, and floodplain restoration programs) that can curb coral reef pollution and can be extended to other countries with similar regulations in place. Coral reef practitioners should consider a broad array of currently underused, actionable, and intersecting environmental policies that can be applied to mitigate coral stress.
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Antozoos , Arrecifes de Coral , Animales , Ecosistema , Políticas , Política AmbientalRESUMEN
Spotted fever rickettsiosis is rarely observed in solid organ transplant recipients, and all previously reported cases have been associated with tick bite months to years after transplantation. We describe a kidney transplant recipient in North Carolina, USA, who had a moderately severe Rickettsia parkeri infection develop during the immediate posttransplant period.
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Trasplante de Riñón , Infecciones por Rickettsia , Rickettsia , Humanos , Trasplante de Riñón/efectos adversos , Rickettsia/genética , Rickettsia/aislamiento & purificación , North Carolina , Infecciones por Rickettsia/diagnóstico , Infecciones por Rickettsia/microbiología , Masculino , Receptores de Trasplantes , Persona de Mediana Edad , Antibacterianos/uso terapéutico , FemeninoRESUMEN
The primary etiology of congenital hearing loss is attributed to genetic factors, with GJB2 identified as a pivotal gene across diverse ethnic groups. Additionally, nonsyndromic hearing loss is predominantly inherited in an autosomal recessive manner. We used Sanger sequencing to analyze GJB2 in 17 deaf children from 13 unrelated Ivory Coast families. One family had two children born with severe congenital deafness and exhibited pathogenic compound heterozygous variants. These variants included a nonsense substitution (c.132G > A or p.Trp44Ter) and a newly discovered duplication of 7 base pairs (c.205_211dupTTCCCCA or p.Ser72ProfsTer32). Segregation testing confirmed these variants, marking the first identification of GJB2 in an Ivorian family with congenital hearing loss.
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Increasingly frequent and intense heatwaves threaten ecosystem health in a warming climate. However, plant responses to heatwaves are poorly understood. A key uncertainty concerns the intensification of transpiration when heatwaves suppress photosynthesis, known as transpiration-photosynthesis decoupling. Field observations of such decoupling are scarce, and the underlying physiological mechanisms remain elusive. Here, we use carbonyl sulphide (COS) as a leaf gas exchange tracer to examine potential mechanisms leading to transpiration-photosynthesis decoupling on a coast live oak in a southern California woodland in spring 2013. We found that heatwaves suppressed both photosynthesis and leaf COS uptake but increased transpiration or sustained it at non-heatwave levels throughout the day. Despite statistically significant decoupling between transpiration and photosynthesis, stomatal sensitivity to environmental factors did not change during heatwaves. Instead, midday photosynthesis during heatwaves was restricted by internal diffusion, as indicated by the lower internal conductance to COS. Thus, increased evaporative demand and nonstomatal limitation to photosynthesis act jointly to decouple transpiration from photosynthesis without altering stomatal sensitivity. Decoupling offered limited potential cooling benefits, questioning its effectiveness for leaf thermoregulation in xeric ecosystems. We suggest that adding COS to leaf and ecosystem flux measurements helps elucidate diverse physiological mechanisms underlying transpiration-photosynthesis decoupling.
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Ecosistema , Transpiración de Plantas , Óxidos de Azufre , Transpiración de Plantas/fisiología , Hojas de la Planta/fisiología , Fotosíntesis/fisiología , Agua/fisiologíaRESUMEN
Climate change is one of the major threats to coastal fish biodiversity, and optimization of no-take marine protected areas (MPAs) is imminent. We predicted fish redistribution under climate change in coastal China Seas with joint species distribution modeling and prioritized areas for conservation with Zonation, for which we used core area zonation (CAZ) and additive benefit function (ABF). Based on our results, we devised an expansion plan of no-take MPAs. Under climate change, fish were redistributed northward along the coast. These redistributions were segmented by the Yangtze River estuary and its adjacent waters, indicating a possible biogeographical barrier. Under CAZ and ABF, significantly more fish habitat was conserved than under random prioritization (p < 0.001, Cohen's d = -0.36 and -0.62, respectively). The ABF better represented areas with higher species richness, whereas CAZ better represented core habitats for species with narrow distributions. Without accounting for species redistribution, the expanded MPAs were mainly distributed in the northwest of the South China Sea, the East China Sea, the north of the Yellow Sea, and the west of the Bohai Sea. When accounting for species redistribution, the proposed MPAs were mainly distributed in the north of the Bohai Sea and southwest of the Yellow Sea, corresponding to the northern species redistributions. These MPAs conserved less habitat for fishes at present but protected more and better quality habitat for fishes in 2050 and 2100 than those MPAs that did not account for species redistribution, indicating improved fish conservation under climate change. Incorporating species redistribution and trade-offs between areas with high species richness and areas that contain habitats for rare species are suggested to address coastal fish conservation under climate change. This work provides valuable information for fish conservation and is a precursor to systematic conservation planning along the coastlines of China Seas.
Mejora de la eficiencia y la resiliencia de las áreas marinas protegidas con veda para la conservación de peces bajo el cambio climático en la costa de los mares de China Resumen El cambio climático es una de las principales amenazas para la biodiversidad de peces costeros, y la mejora de las área marinas protegidas (AMP) con vedas es inevitable. Pronosticamos la redistribución de los peces por el cambio climático en la costa de los mares de China con un modelo de distribución de especies y las áreas priorizadas para la conservación con Zonation, para el cual usamos zonación de las áreas núcleo (ZAN) y la función del beneficio aditivo. (FBA). Con base en nuestros resultados, diseñamos un plan de expansión de AMP con veda. Con el cambio climático, los peces se redistribuyeron hacia el norte a lo largo de la costa. Esta redistribución fue segmentada por el estuario del río Yangtze y las aguas vecinas, indicador de una posible barrera biogeográfica. Con la ZAN y la FBA, se conservó una cantidad significativa de peces en comparación con una priorización aleatoria (p < 0.001, d de Cohen = 0.36 y 0.62, respectivamente). La FBA representó de mejor manera las áreas con una riqueza de especies elevada, mientras que la ZAN representó de mejor manera los hábitats nucleares de las especies con una distribución reducida. Sin contar la redistribución de las especies, las AMP expandidas se localizaron principalmente en el noroeste del Mar del Sur de China, del Mar del Este de China, al norte del Mar Amarillo y al oeste del Mar Bohai. Cuando consideramos la redistribución de las especies, las AMP propuestas se localizaron principalmente al norte del Mar de Bohai y al suroeste del Mar Amarillo, lo que corresponde a la redistribución hacia el norte de las especies. Estas AMP conservaron un menor hábitat de los peces en el presente pero protegieron un mejor hábitat y de mayor calidad para los peces en 2050 y 2100 que las AMP que no consideraron la redistribución de especies, lo que indica una mejora en la conservación de peces bajo el cambio climático. Se sugiere que la incorporación de la redistribución de especies y las compensaciones entre las áreas con una riqueza de especies elevada y las áreas que albergan hábitats para especies raras abordarán la conservación de peces costeros bajo el cambio climático. Esta investigación proporciona información valiosa para la conservación de peces y es un precursor de la planeación sistemática de la conservación a lo largo de la costa de los mares de China.
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Cambio Climático , Resiliencia Psicológica , Animales , Conservación de los Recursos Naturales , Ecosistema , Océanos y Mares , Peces , Biodiversidad , ChinaRESUMEN
INTRODUCTION: Tuberculosis is a global health problem that causes 1. 4 million deaths every year. It has been estimated that sputum smear-negative diagnosis but culture-positive pulmonary TB diagnosis contribute to 12.6% of pulmonary TB transmission. TB diagnosis by smear microscopy smear has a minimum detection limit (LOD) of 5,000 to 10,000 bacilli per milliliter (CFU/ml) of sputum result in missed cases and false positives. However, GeneXpert technology, with a LOD of 131-250 CFU/ml in sputum samples and its implementation is believe to facilitate early detection TB and drug-resistant TB case. Since 2013, Ghana health Service (GHS) introduce GeneXpert MTB/RIF diagnostic in all regional hospitals in Ghana, however no assessment of performance between microscopy and GeneXpert TB diagnosis cross the health facilities has been reported. The study compared the results of routine diagnoses of TB by microscopy and Xpert MTB from 2016 to 2020 at the Cape Coast Teaching Hospital (CCTH). METHODS: The study compared routine microscopic and GeneXpert TB diagnosis results at the Cape Coast Teaching Hospital (CCTH) from 2016 to 2020 retrospectively. Briefly, sputum specimens were collected into 20 mL sterile screw-capped containers for each case of suspected TB infection and processed within 24 h. The samples were decontaminated using the NALC-NaOH method with the final NaOH concentration of 1%. The supernatants were discarded after the centrifuge and the remaining pellets dissolved in 1-1.5 ml of phosphate buffer saline (PBS) and used for diagnosis. A fixed smears were Ziehl-Neelsen acid-fast stain and observed under microscope and the remainings were used for GeneXpert MTB/RIF diagnosis. The data were analyze using GraphPad Prism. RESULTS: 50.11% (48.48-51.38%) were females with an odd ratio (95% CI) of 1.004 (0.944-1.069) more likely to report to the TB clinic for suspected TB diagnosis. The smear-positive cases for the first sputum were 6.6% (5.98-7.25%), and the second sputum was 6.07% (5.45-6.73%). The Xpert MTB-RIF diagnosis detected 2.93% (10/341) (1.42-5.33%) in the first and 5.44% (16/294) (3.14-8.69%) in the second smear-negative TB samples. The prevalence of Xpert MTB-RIF across smear positive showed that males had 56.87% (178/313) and 56.15% (137/244) and females had 43.13% (135/313) and 43.85% (107/244) for the first and second sputum. Also, false negative smears were 0.18% (10/5607) for smear 1 and 0.31% (16/5126) for smear 2. CONCLUSION: In conclusion, the study highlights the higher sensitivity of the GeneXpert assay compared to traditional smear microscopy for detecting MTB. The GeneXpert assay identified 10 and 16 positive MTB from smear 1 and smear 2 samples which were microscopic negative.
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Hospitales de Enseñanza , Microscopía , Mycobacterium tuberculosis , Esputo , Tuberculosis Pulmonar , Humanos , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/genética , Estudios Retrospectivos , Esputo/microbiología , Ghana/epidemiología , Femenino , Adulto , Masculino , Microscopía/métodos , Persona de Mediana Edad , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/microbiología , Adulto Joven , Adolescente , Sensibilidad y Especificidad , Anciano , Técnicas de Diagnóstico Molecular/métodos , Niño , PreescolarRESUMEN
The ability of non-native species to successfully invade new ecosystems sometimes involves evolutionary processes such as hybridization. Hybridization can produce individuals with superior traits that give them a competitive advantage over their parent species, allowing for rapid spread. Here we assess growth, functional morphology, and species interactions between two non-native beachgrass species (Ammophila arenaria and A. breviligulata) and their recently discovered hybrid (A. arenaria × A. breviligulata) on the U.S. Pacific Northwest coast. We asked whether the hybrid beachgrass differs from its parent species in morphology and growth, whether it competes with its parent species, and, if so, what are the potential mechanisms of competition. Plant taxa were grown in low- and high-density monocultures and in two-way interactions in a common garden environment. We show that the hybrid grew taller and more densely, with greater total biomass, than either parent species. The hybrid was also the better competitor, resulting in the model prediction of competitive exclusion against A. breviligulata and, depending on its relative abundance, A. arenaria. The hybrid displays a mixed 'guerilla-phalanx' growth form that allows it to spread laterally and achieve high shoot densities, giving it a competitive advantage. Given the current dominance of A. breviligulata compared to A. arenaria in most of the region where these taxa co-occur, we suggest that the hybrid will grow, compete, and spread quickly with potentially widespread consequences for the two non-native Ammophila congeners and the dunes they build.
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Hibridación Genética , Especies Introducidas , Ecosistema , BiomasaRESUMEN
The global issue of ongoing trace metal emissions and legacy accumulation from diverse sources is posing threats to coastal wildlife. This study characterized the distribution of five metals in relation to dietary ecology (carbon and nitrogen stable isotopes: δ15N and δ13C) in representative predatory species (starfish, fish, and seabird) collected from the coast of Qingdao, northeastern China. Zinc (Zn) was the most abundant metal across species, followed by copper (Cu), chromium (Cr), cadmium (Cd), total and methylated mercury (THg and MeHg). Among the studied species, black-tailed gulls (Larus crassirostris) occupied the highest trophic position, followed by three predatory fish species, whereas the northern Pacific seastar (Asterias amurensis) had the lowest trophic position. The starfish exhibited high capacity to accumulate Cd, Cr and Cu. Conversely, black-tailed gulls exhibited high levels of Zn, while Hg was highest in predatory fishes. Across species, Cr, MeHg, THg and MeHg:THg showed significant positive correlations with δ13C, suggesting the influence of inshore food sources on their accumulation. Both MeHg and THg were significantly and positively correlated with δ15N, with MeHg demonstrating a greater slope, indicating their potential trophic magnification. We assessed health risks from the studied metals using established toxicity reference thresholds. Elevated risks of Hg were identified in three predatory fish species, while other metals and species remain within safe limits. These findings emphasize the significance of foraging patterns in influencing trace metal accumulation in coastal predators and highlight the importance of further monitoring.
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Mercurio , Oligoelementos , Contaminantes Químicos del Agua , Animales , Cadmio , Cadena Alimentaria , Monitoreo del Ambiente , Mercurio/análisis , Metales/toxicidad , Isótopos de Nitrógeno , Zinc , Contaminantes Químicos del Agua/análisis , PecesRESUMEN
BACKGROUND: There is a growing body of evidence on the effect of the local environment exposure on cancer susceptibility. Nonetheless, several of the associations remain controversial. Moreover, our understanding of the possible interaction between the local environment and the genetic variability is still very limited. OBJECTIVE: The aim of this study was to clarify the role of the local environment and its possible interplay with genetics on common cancers development. METHODS: Using the UK Biobank (UKBB) prospective cohort, we selected 12 local environment exposures: nitrogen oxides, nitrogen dioxides, particulate matter (10 and 2.5 µm), noise pollution, urban traffic, living distance from the coast, percentage of greenspace, natural environment, water, and domestic garden within 1000 m from the residential coordinates of each participant. All these exposures were tested for association with 17 different types of cancer for a total of 53,270 cases and 302,645 controls. Additionally, a polygenic score (PGS) was computed for each cancer, to test possible gene-environment interactions. Finally, mediation analyses were carried out. RESULTS: Thirty-six statistically significant associations considering multiple testing (p < 2.19 × 10-4) were observed. Among the novel associations we observed that individuals living farther from the coast had a higher risk of developing prostate cancer (OR = 1.13, CI95% = 1.06-1.20, P = 1.98 × 10-4). This association was partially mediated by physical activity (indirect effect (IE) = -8.48 × 10-7) and the time spent outdoor (IE = 9.07 × 10-6). All PGSs showed statistically significant associations. Finally, genome-environment interaction analysis showed that local environment and genetic variability affect cancer risk independently. DISCUSSION: Living close to the coast and air pollution were associated with a decreased risk of prostate cancer and skin melanoma, respectively. These findings from the UKBB support the role of the local environment on cancer development, which is independent from genetics and may be mediated by several lifestyle factors.
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Contaminantes Atmosféricos , Contaminación del Aire , Neoplasias de la Próstata , Masculino , Humanos , Contaminantes Atmosféricos/análisis , Estudios Prospectivos , Biobanco del Reino Unido , Bancos de Muestras Biológicas , Contaminación del Aire/análisis , Material Particulado , Exposición a Riesgos Ambientales , Variación Genética , Células Germinativas/químicaRESUMEN
To better understand the ecological effects of mariculture, the diversity distribution, determinant and interaction of microeukaryote communities from fish cage and suspended shellfish farming were investigated in three bays of South China Coast. Our alpha and beta diversity analyses showed that the difference of the microeukaryote community between fish and shellfish farming was more significant at local than regional scale, and microeukaryotes respond more to spatial effect than mariculture effect at regional scale. Mantel test, variation partitioning analysis and co-occurrence network analysis revealed that the environmental factors especially chemical and biotic factors contributed more to community assembly in fish than shellfish farming. Based on the comparisons of community composition and determinant between fish and shellfish farming, the effect mechanisms of the two farming types on microeukaryote community were proposed. Fish farming brings significant environmental variation and thus has strong bottom-up impacts on microeukaryotes, while shellfish farming exerts a grazing pressure on microeukaryotes by filter-feeding and has top-down control to them. Furthermore, the network stability analyses revealed weaker community stability in fish than shellfish farming, suggesting that the microeukaryote community was more sensitive to environmental change deduced by fish than shellfish farming. Overall, this study revealed the different influencing mechanisms of fish and shellfish mariculture on microeukaryotes, which will improve the understanding of the ecological effects of mariculture and provide guidance for the management of mariculture under future environmental pressures.
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Acuicultura , Mariscos , Animales , Peces , Agricultura , ChinaRESUMEN
Patterns in parasite diversity are shaped by their environmental and ecological settings, and to better understand their interactions with hosts and the corresponding biology, it is crucial to understand these context-dependent patterns. To achieve this, we use cymothoid isopods, an important group of fish parasites, to test a long-standing hypothesis about parasite diversity and prevalence pattern: whether semi-enclosed water bodies allow low diversity and high prevalence of parasitic isopods. Specifically, we compare these patterns between Chilika lagoon (Odisha, India), a semi-enclosed water body, and the adjoining Odisha coast (India). Our finding reveals that the semi-enclosed Chilika lagoon has a considerably lower diversity of parasitic isopods than its adjoining open sea along the Odisha coast. Additionally, the parasitic isopod infection levels in Chilika lagoon are noticeably higher, and isopod assemblage is less even than those in coastal waters along the Odisha coast. Our results support the hypothesised association between enclosed water bodies, parasite diversity, and host prevalence and contribute to an enhanced comprehension of the ecology of parasitic isopods in distinct marine environments.
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Isópodos , Parásitos , Animales , Ecosistema , Prevalencia , India , AguaRESUMEN
Weathering processes are recognized as drivers of soil and water resource sustainability, but how pedogenesis stage impacts contaminant reactivity and mobility in soils has been minimally investigated. The primary goal of this study was to quantify how soil development influences contaminant reactivity. To achieve this goal, soils from two depths (30 and 100 cm) across a chronosequence (ages 3.5, 20, 69, 140, 200, and 908 ky) in the Oregon Coast Range were subjected to arsenic (As) adsorption isotherms, with As removal from solution serving as a proxy for soil-contaminant reactivity. Langmuir models were applied to isotherm data to quantify relationships between contaminant retention capacity, soil age and soil physicochemical properties, and data revealed that 20 ky soils from a 30-cm-depth had the greatest affinity for As sorption (8,474.5 mg kg-1). Chemical extractions revealed that amorphous (oxy)hydroxides were the dominant mineral phases governing As sorption, even in the presence of abundant crystalline oxides. Micro-X-ray fluorescence spectroscopy revealed a strong spatial correlation between As and Fe in reacted soils. The abundance of amorphous minerals within soils is controlled by the balance between their production from weathering of primary minerals and their loss from ripening to crystalline minerals, and because the mode, extent and minerals governing contaminant sorption determine solid-aqueous phase partitioning, this knowledge will assist in improving models for predicting Critical Zone processes that govern the sustainability of soil and water quality.
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Multi-hazards are a great concern in the present world. Likewise, the coastal part of Bangladesh is highly vulnerable to multi-hazards, including waterlogging, surface water salinity, land use change, prolonged dry seasons, and groundwater salinity. Multi-hazards and associated risks make local adaptations more difficult over time. Thus, the purpose of this study is to explore the connection between multi-hazards and their associated socio-ecological risks in the southwestern coastal part of Bangladesh. Mixed-methods approaches were used to collect all the data, and statistical analyses were performed to analyze the data. Results revealed that waterlogging significantly influenced local food access, poverty, child marriage, and divorce problems. Surface water salinity and land use change showed significant differences with the widening of salinity-affected areas. Waterlogging, land use change, and a prolonged dry season all showed significant differences in freshwater access. Prolonged dry seasons and groundwater salinity both have a significant impact on human health. Waterlogging and groundwater salinity significantly influence human migrations. These findings may strengthen local adaptation policies for salinity hazards, land use planning, household poverty, food access, livelihoods, water access, health effects, child marriage, and human migration. In addition, our findings indicate the potential to address the existing knowledge gaps pertaining to coastal hazards, risks, and adaptation issues.
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Agua Subterránea , Agua , Humanos , Bangladesh , Agua Dulce , Salinidad , Estaciones del AñoRESUMEN
Pollution by microplastics (MPs) in mangroves is a growing concern, given its potential ecological and human health impacts. The characteristics of microplastic pollution and a risk assessment of MPs in the Amazon region's coastal sediments are still insufficient, and information about MP pollution in the benthic component of the mangrove ecosystem is lacking. We analyzed MP concentrations in the surface sediment of 9 stations in three tidal channels along the Ajuruteua Peninsula connected to the Caeté River estuary, aiming to assess the hazard level on the environment based on the Pollution Load Index (PLI). Raman and Fourier transform infrared spectroscopy determined the MP's chemical composition. The results showed that the abundance of sediment MPs ranged from 100 to 1200 items kg-1, with an average of 433 ± 261.6 items kg-1. The MPs were mainly composed of transparent and blue fragments and fibers, ranging in size from 100 to 5000 µm. Six types of polymers were identified, including alkyd varnish (AV), resin dispersion (RD), chlorinated polyethylene (CPE), polyethylene-polypropylene (PE-PP), low-density polyethylene (LDPE), and hostaperm blue (HB). Hydrodynamic processes within estuaries and tidal channels play a crucial role in explaining the concentrations found, as circulation determines the pattern of sediment deposition and the particles adhered to it. PLI risk assessment showed that all sampling sites were at hazard level I: a low level of contamination in the mangrove sediments. However, a more comprehensive and systematic monitoring campaign is needed to expand our knowledge about pollution and contamination by MPs in Amazon mangrove areas.
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Monitoreo del Ambiente , Sedimentos Geológicos , Microplásticos , Microplásticos/análisis , Microplásticos/toxicidad , Brasil , Medición de Riesgo , Sedimentos Geológicos/química , Sedimentos Geológicos/análisis , Humedales , Contaminantes Químicos del Agua/análisisRESUMEN
Suspended particulate matter (SPM) plays a crucial role in assessing the health status of coastal ecosystems. Satellite remote sensing offers an effective approach to investigate the variations and distribution patterns of SPM, with the performance of various satellite retrieval models exhibiting significant spatial heterogeneity. However, there is still limited information on precise remote sensing retrieval algorithms specifically designed for estimating SPM in tropical areas, hindering our ability to monitor the health status of valuable tropical ecological resources. A relatively accurate empirical algorithm (root mean square error = 2.241 mg L-1, mean absolute percentage error = 42.527%) was first developed for the coastal SPM of Hainan Island based on MODIS images and over a decade of field SPM data, which conducted comprehensive comparisons among empirical models, semi-analytical models, and machine learning models. Long-term monitoring from 2003 to 2022 revealed that the average SPM concentration along the coastal wetlands of Hainan Island was 6.848 mg L-1, which displayed a decreasing trend due to government environmental protection regulations (average rate of change of -0.009 mg L-1/year). The seasonal variations in coastal SPM were primarily influenced by sea surface temperature (SST). Spatially, the concentrations of SPM along the southwest coast of Hainan Island were higher in comparison to other waters, which was attributable to sediment types and ocean currents. Further, anthropogenic pressure (e.g., agricultural waste input, vegetation cover) was the main influence on the long-term changes of coastal SPM in Hainan Island, particularly evident in typical tropical ecosystems affected by aquaculture, coastal engineering, and changes in coastal green vegetation. Compared to other typical ecosystems around the globe, the overall health status of SPM along the coast wetlands of Hainan is considered satisfactory. These findings not only establish a robust remote sensing model for long-term SPM monitoring along the coast of Hainan Island, but also provide comprehensive insights into SPM dynamics, thereby contributing to the formulation of future coastal zone management policies.
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Monitoreo del Ambiente , Islas , Material Particulado , Material Particulado/análisis , Tecnología de Sensores Remotos , Ecosistema , Imágenes Satelitales , ChinaRESUMEN
Submarine Groundwater Discharge (SGD) and Seawater Intrusion (SWI) are two contrary hydrological processes that occur across the land-sea continuum and understanding their nature is essential for management and development of coastal groundwater resource. Present study has attempted to demarcate probable zones of SGD and SWI along highly populated Odisha coastal plains which is water stressed due to indiscriminate-exploitation of groundwater leading to salinization and fresh groundwater loss from the alluvial aquifers. A multi-proxy investigation approach including decadal groundwater level dynamics, LANDSAT derived sea surface temperature (SST) anomalies and in-situ physicochemical analysis (pH, EC, TDS, salinity and temperature) of porewater, groundwater and seawater were used to locate the SGD and SWI sites. A total of 340 samples for four seasons (85 samples i.e., 30 porewater, 30 seawater and 25 groundwater in each season) were collected and their in-situ parameters were measured at every 1-2 km gap along ~ 145 km coastline of central Odisha (excluding the estuarine region). Considering high groundwater EC values (> 3000 µS/cm), three probable SWI and low porewater salinities (< 32 ppt in pre- and < 25 ppt in post-monsoons), four probable SGD zones were identified. The identified zones were validated with observed high positive hydraulic gradient (> 10 m) at SGD and negative hydraulic gradient (< 0 m) at SWI sites along with anomalous SST (colder in pre- and warmer in post-monsoon) near probable SGD locations. This study is first of its kind along the Odisha coast and may act as initial basis for subsequent investigations on fresh-saline interaction along the coastal plains where environmental integrity supports the livelihood of coastal communities and the ecosystem.
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Monitoreo del Ambiente , Agua Subterránea , Salinidad , Agua de Mar , Agua Subterránea/química , Agua de Mar/química , India , Monitoreo del Ambiente/métodos , Movimientos del Agua , Temperatura , Estaciones del AñoRESUMEN
In the early- to mid-nineteenth century, European mortality rates in West Africa were the highest in the world. Mortality estimates included nine missionaries sent from the Basel Mission (established in what is now Switzerland) to the Gold Coast (present-day Ghana), eight of whom died between 1828 and 1840, mostly from "fevers." In response to high mortality rates, the Basel Mission recruited several Afro-West Indians to work as Christian missionaries in the Gold Coast, mostly based on the presumption that individuals of African descent would better survive the environment. The decision to recruit Afro-West Indians to evangelize on the Gold Coast seemed to the mission to be a rational decision, one not in need of further justification or an overarching theory of race, environment, and disease. Surprisingly, the Basel Mission did not justify this position Biblically either. Once arrived, the West Indian Christian missionaries mostly lived in the Akwapem hills above Accra at an elevation that would have provided some protection against malaria; subsequently, their mortality rates were significantly lower than the European missionaries. After quinine came to be used as a prophylactic against malaria after 1850, thus lowering European missionary mortality rates, no more Afro-West Indians were recruited by the Basel Mission.
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The surface sediments from eleven sectors perpendicular to the Egyptian Mediterranean Sea coast, along the delta region, have been assessed. These sectors cover areas of Eastern Harbour, Abu Qir Bay, Rosetta, Abo Khashaba, Burullus, Baltim, Damietta, and Manzala. The assessment process is based on determining the eight metals' (Fe, Cu, Zn, Mn, Ni, Co, Pb, and Cd) content, followed by applying different pollution and ecological risk indices such as enrichment factor (EF), geoaccumulation factor (Igeo), contamination factor (CF), Pollution Load Index (PLI), degree of contamination (Cdeg.), Nemerow Integrated Pollution Index (NIPI), and Potential Ecological Risk Index (PERI). The results indicate the average concentrations of metals (µg/g) were Fe (18,000), Mn (213), Zn (120), Ni (26), Co (13), Cu (12), Pb (10), and Cd (2). The single-pollution indices reveal that most metals were depleted to metal levels, the sediments were moderately polluted with Cd and unpolluted with other metals, and the CF values confirmed that the sediments were highly polluted with Cd and low contaminated with the rest of the metals. According to the integrated pollution indices, the Eastern Harbour, Damietta, Manzalah, and Bardawil (eastern Inlet) are the most polluted sectors relative to the rest, subjected to various point sources of pollution. Drainage management system is recommended to enhance water conservation and improve fish stocks.
Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Metales Pesados/análisis , Egipto , Cadmio , Plomo , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos , Medición de RiesgoRESUMEN
Natural disasters such as earthquakes endanger human lives and infrastructure, particularly in urban areas. With the advancements in science and technology in understanding natural hazards, recent studies have attempted to mitigate them by mapping the risks using geospatial technology. In this paper, we attempt to integrate the multi-criteria decision-making (MCDM) models, namely the Analytical Hierarchy Process (AHP) and the Criteria Importance Through Inter-criteria Correlation (CRITIC), besides using the artificial neural network (ANN) to assess the seismic risk in the eastern coast of India. The AHP-CRITIC technique is used to evaluate the earthquake coping capacity and vulnerability and has been further used to generate a training base for earthquake probability mapping by ANN. The earthquake probability and spatial intensity information are used to develop the hazard map. Following that, integrating vulnerability, hazard and coping capacity spatial information assessed earthquake risk. Our results indicate that approximately 5% of the study area is at high risk, whilst more than 11% of the population is at high risk due to seismic induced hazards. The area under the curve of the receiver operating characteristic curve is 0.85, which indicates reliable results. The results of this study may help various agencies involved in planning, development and disaster mitigation to develop seismic hazard mitigation methods by better understanding their impacts on the eastern coastal region of India.