Contamination In Coastal Areas Research Articles

Drinking Water Resources Suitability Assessment Based on Pollution Index of Groundwater Using Improved Explainable Artificial Intelligence

The global significance of fluoride and nitrate contamination in coastal areas cannot be overstated, as these contaminants pose critical environmental and public health challenges across the world. Water quality is an essential component in sustaining environmental health. This integrated study aimed to assess indexical and spatial water quality, potential contamination sources, and health risks associated with groundwater resources in Al-Hassa, Saudi Arabia. Groundwater samples were tested using standard methods. The physiochemical results indicated overall groundwater pollution. This study addresses the critical issue of drinking water resource suitability assessment by introducing an innovative approach based on the pollution index of groundwater (PIG). Focusing on the eastern region of Saudi Arabia, where water resource management is of paramount importance, we employed advanced machine learning (ML) models to forecast groundwater suitability using several combinations (C1 = EC + Na + Mg + Cl, C2 = TDS + TA + HCO3 + K + Ca, and C3 = SO4 + pH + NO3 + F + Turb). Six ML models, including random forest (RF), decision trees (DT), XgBoost, CatBoost, linear regression, and support vector machines (SVM), were utilized to predict groundwater quality. These models, based on several performance criteria (MAPE, MAE, MSE, and DC), offer valuable insights into the complex relationships governing groundwater pollution with an accuracy of more than 90%. To enhance the transparency and interpretability of the ML models, we incorporated the local interpretable model-agnostic explanation method, SHapley Additive exPlanations (SHAP). SHAP allows us to interpret the prediction-making process of otherwise opaque black-box models. We believe that the integration of ML models and SHAP-based explainability offers a promising avenue for sustainable water resource management in Saudi Arabia and can serve as a model for addressing similar challenges worldwide. By bridging the gap between complex data-driven predictions and actionable insights, this study contributes to the advancement of environmental stewardship and water security in the region.

Modelling based study on the occurrence characteristics and influencing factors of the typical antibiotics in Bohai Bay

Previous studies have demonstrated that antibiotics have the potential impacts to ecosystems and human health. However, due to their various classes and distinct characteristics, creating comprehensive, integrated and dynamic simulations has proven to be a challenging task. In this study, a 3D hydrodynamic-contaminant model was developed to gain a better understanding of the transportation and prevalence of antibiotics in the Bohai Bay. Specifically, we focused on four types of antibiotics as examples. To accurately capture the dynamic distribution of antibiotics, both transport and biochemical processes were taken into account. Based on this model, the antibiotics' spatial and temporal distribution was examined, the potential impact of the future antibiotics consumption and climate change was also analyzed. The study found that human activity has a greater impact on the presence of antibiotics in Bohai Bay than temperature rise. Based on the current consumption rate, the total amount of antibiotics in Bohai Bay may increase by 10 ng/L and affect nearly one third of the study area within the next 20–30 years. The significant impact of human activity on water contamination in coastal areas may also have implications for other coastal regions. This finding can provide a valuable framework for pollution prevention and control.

Investigation on the Hydrogeochemical Characteristics and Controlling Mechanisms of Groundwater in the Coastal Aquifer

Groundwater contamination in coastal areas has attracted widespread attention. However, studies on the hydrogeochemical characteristics and controlling mechanisms in coastal aquifers are still lacking. In this study, 71 sets of groundwater samples were collected during the dry and wet seasons in a coastal city, Shandong Province. Correlation and principal component analyses were used to identify pollution sources. Meanwhile, Piper diagrams, Gibbs plots, ion ratios, and saturation indices were employed to investigate the hydrogeochemical controlling mechanisms. The results revealed that pollution components included Na+, NH4+, Cl−, SO42−, NO3−, NO2−, Pb, As, Se, TDS, TH, F−, and Mn. Pollution compositions in the study area were primarily derived from natural processes and anthropogenic activities. The contamination of nitrogen resulted primarily from agricultural activities. The exceedance of SO42− was mainly due to the leaching of waste by rainfall. High Na+, Cl−, and F− were related to sea intrusion. Pb and Se might have been caused by anthropogenic activities. The exceedance of As was caused by anthropogenic inputs and natural factors. The poor seepage conditions and anoxic conditions promoted the enrichment of Mn. The concentration of most components in the dry season was larger than that in the wet season. There were no significant differences in water chemistry type during the wet season and dry season. Groundwater chemical compositions were dominated by the dissolution of halite, gypsum, and anhydrite, as well as the cation exchange reaction. The influence of seawater intrusion on groundwater was not serious.

COVID-19 personal protective equipment (PPE) contamination in coastal areas of Granada, Spain

The use of disposable personal protective equipment (PPE) as a control measure to avoid transmission against COVID-19 has generated a challenge to the waste management and enhances plastic pollution in the environment. The research aims to monitor the presence of PPE waste and other plastic debris, in a time interval where the use of face mask at specific places was still mandatory, on the coastal areas of Granada (Spain) which belongs to the Mediterranean Sea. Four beaches called La Rijana, La Charca, La Rábita and Calahonda were examined during different periods. The total amount of sampled waste was 17,558 plastic units. The abundance, characteristics and distribution of PPE and other plastic debris were determined. Results showed that the observed amount of total plastic debris were between 2.531·10−2 and 24.487·10−2 units per square meter, and up to 0.136·10−2 for PPE debris, where face masks represented the 92.22 % of the total PPE debris, being these results comparable to previous studies in other coastal areas in the world. On the other hand, total plastic debris densities were in the range from 2.457·10−2 to 92.219·10−2 g/m2 and densities were up to 0.732·10−2 for PPE debris. PPE debris supposed 0.79 % of the weight of total waste and the 0.51 % of total items. Concerning non-PPE plastic waste: cigarettes filters, food containers and styrofoam were the most abundant items (42.95, 10.19 and 16.37 % of total items, respectively). During vacation periods, total plastic debris amount increased 92.19 % compared to non-vacation periods. Regarding type of beaches, the presence of plastic debris was significantly higher on touristic/recreational than in fishing beaches. Data showed no significant differences between accessible and no-accessible beaches, but between periods with restrictive policy about mask face use and periods with non-restrictive policy data suggest significant differences between densities (g/m2) for PPE litter. The amount of PPEs debris is also correlated with the number of cigarettes filters (Person's r = 0.650), food containers (r = 0.782) and other debris (r = 0.63). Finally, although interesting results were provided in this study, further research is required to better understand the consequences of this type of pollution and to provide viable solutions to this problem.

Chemical hazard of robotic hull in-water cleaning discharge on coastal embryonic fish

In-water cleaning (IWC) involves the removal of biofilms and foulants from the hull of a ship using brush or water jet. During IWC, several factors associated with the harmful chemical contaminants release to the marine environment, which can create “hotspots” of chemical contamination in coastal areas. To elucidate the potential toxic effects of IWC discharge, we investigated developmental toxicity in embryonic flounder, which are sensitive life stage to chemical exposure. Zinc and copper were the dominant metals, while zinc pyrithione was the most abundant biocide associated with IWC discharge in two remotely operated IWC. Discharge from IWC carried by both remotely operated vehicles (ROVs) produced developmental malformations including pericardial edema, spinal curvature, and tail-fin defects. In an analyses of differential gene expression profiles (fold-change of genes with a cutoff < 0.05) as assessed by high-throughput RNA sequencing, genes associated with muscle development were commonly and significantly changed. The gene ontology (GO) of embryos exposed to IWC discharge from ROV A activities highly enriched muscle and heart development, while cell signaling and transport were evident in embryos exposed to IWC discharge of ROV B. We analyzed the gene network by significant GO terms. In the network, TTN, MYOM1, CASP3, and CDH2 genes appeared to be key regulators of the toxic effects on muscle development. In embryos exposed to ROV B discharge, HSPG2, VEGFA, and TNF genes related to the nervous system pathway were affected. These results shed light on the potential impacts of muscle and nervous system development in non-target coastal organisms exposed to contaminants found in IWC discharge.

Target and Suspect Analysis with High-Resolution Mass Spectrometry for the Exhaustive Monitoring of PCBs and Pesticides in Posidonia oceanica Meadows and Sediments

This study enables the simultaneous monitoring of persistent organics pollutants (POPs) in the relevant marine seagrass Posidonia oceanica (L.) Delile (P. oceanica), without causing damage and preserving their ecological integrity and their key ecosystem services, and in marine sediments. Two classes of POPs that suppose a current threat to the environmental health status are investigated: polychlorinated biphenyls (PCBs) and pesticides. Comparisons between tissues and sediment compartmentation are studied for the first time. For these purposes, the sediments, P. oceanica leaves and, as a novelty, rhizomes, were studied. Samples were analyzed by gas chromatography coupled with high-resolution mass spectrometry (GC-Q-Orbitrap MS) for a comprehensive study. Eco-friendly methods were developed and validated for the determination of 38 POPs, 25 PCBs and 13 priority pesticides. The results showed that, when detected, regulated contaminants were localized mainly in the long-lived rhizomes, and 7 PCBs (the most abundant being PCB 44) and 4 priority pesticides (trifluralin, chlorpyrifos, isodrin and o,p’-DDT) were seen. Additionally, a retrospective analysis (suspect screening) was conducted, exhibiting up to 13 current-use pesticide residues in leaves and rhizomes alike. The results suggest that P. oceanica might be acting as a sink to contaminants in coastal areas and that rhizomes, due to their longer lifespan, reflect past and legacy contamination.

Weathering of microplastics and their enhancement on the retention of cadmium in coastal soil saturated with seawater

The plastic contamination and its associated ecological impacts in coastal areas have received great concern. The environmental conditions of varying aquatic-terrestrial ecosystems and physicochemical properties of existing plastics may further affect the transport and fate of subsequent entering contaminants in coastal areas. In this study, a coastal soil accumulated with five commonly-used micro-sized plastics (MPs) and saturated with four seawaters collected along the China coastlines from north to south were applied to investigate their effects on the mobility of Cd. The existing MPs in soil greatly enhanced Cd accumulation, with Cd retention increasing to 23.1 – 78.6%, compared to 18.1 – 26.6% in the soil without MPs. The five MPs showed the increasing trend of Cd retention: polystyrene < polyethylene < polypropylene < polyvinyl chloride < polyethylene terephthalate. The highest Cd retention by polyethylene terephthalate was attributed to its rich oxygen-containing groups which could enhance Cd sorption. The aged MPs was characterized by more oxygen-containing functional groups with higher surface charge, which enhanced the electrostatic interaction with Cd. Modeling showed that the depths for the maximum concentrations of Cd downward migration in the MPs soil are only down to 9 cm after 10-year seawater intrusion, while the depths go down to 26 cm in the soil alone. Overall, MPs existing in soil can retain more Cd in the surface soil, which impel our great attention of the combined pollution of existing microplastics and subsequent entering heavy metals in the coastal topsoil.

Chemical contamination in coastal areas alters shape, resistance and composition of carnivorous gastropod shells

Morphological, structural and compositional alterations in shells of molluscs have been proposed as putative biomarkers of chemical contamination in coastal zones. Despite this, few studies were carried out using top predator gastropods which tend to be more susceptible to contamination exposure. Thus, the present study assessed disturbances on shells of Stramonita brasiliensis considering compression resistance and organic and mineralogical matrix composition, related to morphometric alterations. Results showed reductions in compression resistance and organic matrix content associated with higher contaminated sites. In addition, a predominance of calcite polymorphs was seen in shells obtained in polluted areas. Such outputs were consistent with local contamination levels which may have induced the observed alterations. Thus, changes in mollusc shells showed good performance as potential biomarkers of coastal contamination, being probably observed in other species of carnivorous gastropods around the world.

Trace metal content in sediment cores and seagrass biomass from a tropical southwest Pacific Island

A unique feature of seagrass among other ecosystem services is to have high phytoremediation potential that is a cost-effective plant-based approach and environmentally friendly solution for metal contamination in coastal areas. The goal of this study was to assess the phytoremediation prospective of seagrass for Cu, Fe, Mn and Zn in Fiji Islands. Heavy metal content was measured in sediments and tissues of the seagrasses Halophila ovalis, Halodule pinifolia and Halodule uninervis to test for local-scale differences. The local study shows that metal concentration in sediment and seagrass tissue was significantly variable, regardless of species and sediment type. Sedimentary concentration of Cu, Fe, Mn and Zn obtained in the present study seemed to be lower than that of previous studies. The results support that H. ovalis is a good bioindicator species since it accumulated up to 5-fold more of these metals compared to the Halodule species.

Benthic foraminifera geochemistry as a monitoring tool for heavy metal and phosphorus pollution — A post fish-farm removal case study

Measuring environmental contaminants in coastal areas is critical for monitoring and managing their impacts. Commonly used techniques involve repetitive field sampling, which provides a single moment in time during each effort. In this study, we examine the potential for using foraminifera in monitoring and risk assessment as recorders of bioavailable pollutants. Geochemical analysis of benthic foraminifera (Operculina ammonoides) shells sampled annually at a previous fish farm location showed extremely high levels of copper (Cu), zinc (Zn), and phosphorus (P) during the three years following the fish cages removal, with a general reduction afterwards. Levels of Cu/Ca were still more than 4-fold higher than background levels 10 years after the removal of the fish cages. Based on our finds, it is concluded that the geochemical analysis of recent benthic foraminifera shells can serve as a powerful monitoring tool of bioavailable contaminants in seawater. Additionally, the results highlight the need for heavy metal monitoring near marine aquaculture facilities and suggest that long-term effects extend spatially and temporally far beyond the original point source. Finally, we observed variations in micro-distribution of elements within the top 1–2 μm of the shells, where Cu/Ca, Zn/Ca and P/Ca are consistently higher in the chamber wall than in the septa. This observation is relevant for studies conducting single chamber analyses.

Interactive effects of increased temperature and gadolinium pollution in Paracentrotus lividus sea urchin embryos: a climate change perspective

Gradual ocean warming and marine heatwaves represent major threats for marine organisms already facing other anthropogenic-derived hazards, such as chemical contamination in coastal areas. In this study, the combined effects of thermal stress and exposure to gadolinium (Gd), a metal used as a contrasting agent in medical imaging which enters the aquatic environment, were investigated in the embryos and larvae of the sea urchin Paracentrotus lividus. Embryos were exposed to six treatments of three temperatures (18 °C, 21 °C, 24 °C) and two Gd concentrations (control: 0 μM; treated: 20 μM). With respect to developmental progression, increased temperature accelerated development and achievement of the larval stage, while Gd-exposed embryos at the control temperature (18 °C) showed a general delay in development at 24 h post-fertilization (hpf), and a stunting effect and impaired skeleton growth at 48 hpf. Elevated temperatures at near-future projections (+3 °C, 21 °C) reduced the negative effects of Gd on development with a lower percentage of abnormality and improved skeleton growth. Combined extreme warming at present-day marine heatwave conditions (+6 °C, 24 °C) and Gd treatment resulted in a lower proportion of embryos reaching the advanced larval stages compared to the 21 °C + Gd. At the molecular level, western blot analysis showed that Gd was the main driver for the induction of heat shock protein (HSP60, HSP70) expression. At 48 hpf, temperature increase was the main driver for activation of additional cellular stress response strategies such as autophagy and apoptosis. Combined treatments showed the induction of HSP60 at 24 hpf and autophagic and apoptotic processes at 48 hpf. Treatments having low levels of HSPs expression showed high levels of apoptosis, and vice versa, clearly demonstrating the antagonistic effects of HSPs expression and apoptosis. Detection of fragmented DNA in apoptotic nuclei showed selective apoptosis, likely in extremely damaged cells. Our results indicate that the negative effects of Gd-exposure on P. lividus larval development and biomineralization will be mitigated by a near-future ocean warming, up to a thermotolerance threshold when negative synergistic effects were evident. Our data highlight the use of biomarkers as sensitive tools to detect environmental impacts as well as the need for a better understanding of the interactions between the multiple stressors faced by marine species in coastal environments.

The panpulmonate limpet Siphonaria lessonii Blainville, 1827 as a sentinel of contamination in coastal areas of Argentina

Although some studies have evaluated the use of Siphonaria lessonii as a bioindicator of pollution, no study has identified the effects of human activities on the digestive gland, which is the main centre of detoxification of xenobiotics and a target organ in contamination studies. Thus, the present work aims to evaluate the use of this species as a suitable sentinel of contamination by analysing the digestive gland and shell alterations. The study was carried out in three populations exposed to different degrees of anthropogenic impact in the coast of Buenos Aires: a reference site (VG), a mid-impacted site (MPL) and a highly-impacted site (MPP). A histological analysis of the digestive gland was performed, as well as an assessment of the geometric morphometry, thickness, density and microstructure of the shell. Our results indicated that the individuals from the impacted sites present several histological alterations in the tubules of the digestive gland. These included hypertrophy and hyperplasia of different cell types (MPP), alterations of the digestive tube morphology (MPL and MPP), the presence of lipofuscin-like substances (MPL) and a high inflammatory response (MPP). In the shells, neither microstructural malformations nor changes in the elemental composition were found. However, shell morphometric variations and a decrease in shell hardness (thickness and density) were observed in the impacted sites. In conclusion, our results indicate that S.lessonii is a well-suited sentinel of contamination since the effects of anthropogenic impact may be reflected in both soft and hard structures. Although further investigations are necessary to identify the relationship between these effects and their potential causing agents, these simple and low-cost methodological approaches could be used to diagnose disturbance in the ecosystem health status where this species inhabits.

Anthropogenic impacts on the contamination in the coastal region: A review

This review paper intend to evaluate the susceptibility of coastal areas to sectoral pressures from socio-economic behaviour. Pharmaceuticals and personal care products (PPCPs) are predictable as one of the emerging group of environmental contaminants, incarcerate worldwide consideration. These chemicals are generated from anthropogenic activities from human, which directly enter into coastal regions. The parameters preferred for this index focuses on five significant vectors: marine spills, port activities, tourism, protection of natural areas, and water and waste management.Due to chemicals exposure the colour of water become yellow and the living organisms in water get diversified and depleted. The study relates the different seven major contaminants in coastal areas are Sulfamethoxazole, sulfamethazine, oxytetracycline, ofloxacin, roxithromycin, anhydro-erythromycin. The contaminations in coastal water were confirmed by three anthropogenic factors such as (1) discharge of Wastewater, (2) Waste from meat, milk products, poultry etc and (3) nasty aquatic produce. Overall the ecological risk is comparable and identified this contaminants migration is more.

Is hull cleaning wastewater a potential source of developmental toxicity on coastal non-target organisms?

Chemical contaminants can be discharged by vessel hull cleaning processes, such as scraping, jet spraying, and painting, all of which produce readily transportable contaminants into the marine environment, where they are referred to as ‘hotspots’ of contamination in coastal areas. However, many countries have not yet established effective evaluation methods for disposal of waste mixtures or management guidelines for areas of hull cleaning. To define the toxic effects of wastewater from vessel hull cleaning in dry docks on resident non-target organisms, we investigated the chemical concentrations and developmental toxicity on embryonic flounder, which is an organism sensitive to chemical contamination. In this study, the dominant inorganic metal discharged was zinc when cleaning Ship A (300 tons) and copper for Ship B (5,000 tons). The wastewater from high-pressure water blasting (WHPB) of Ship A (300 tons) and Ship B (5,000 tons) produced a largely overlapping suite of developmental malformations including pericardial edema, spinal curvature, and tail fin defects. Forty-eight hours after exposure, the frequency percentage of malformation began to increase in embryos exposed to a 500-fold dilution of WHPB from Ships A and B. We performed transcriptome sequencing to characterize the toxicological developmental effects of WHPB exposure at the molecular level. The results of the analysis revealed significantly altered expression of genes associated with muscle cell differentiation, actin-mediated cell contraction, and nervous system development (cutoff P < 0.01) in embryonic flounder exposed to high-pressure cleaning effluent from Ship A. Genes associated with chromatin remodeling, cell cycling, and insulin receptor signaling pathways were significantly altered in embryonic flounder exposed to WHPB of Ship B (cutoff P < 0.01). These findings provide a greater understanding of the developmental toxicity and potential effects of WHPB effluent on coastal embryonic fish. Furthermore, our results could inform WHPB effluent management practices to reduce impacts on non-target coastal organisms.

Resolving the thickness of peat deposits with contact-less electromagnetic methods: A case study in the Venice coastland

Peat soils are typical deposits characterizing wetlands and reclaimed farmlands. They are important carbon reservoirs and when degraded (e.g., erosive processes, fires, draining and plowing) massive carbon dioxide volumes are released. This leads to increase greenhouse effect and induce serious land subsidence. Thus, mapping the volume of peat deposits is crucial in order to estimate the carbon mass and the potential release of carbon dioxide and consequent loss in soil elevation. Despite the importance of such estimations, forecasting and quantifying the peat thickness is still a challenge. Direct sediment coring provides local information that is difficult to extend to large territories. Indirect geophysical methods are unable to resolve lithological contrasts in the presence of saltwater contamination in coastal areas. In this work, we show the results obtained using two contact-less electromagnetic methods for the characterization of peat deposits in a peatland site of the Venice coastland, Italy. Specifically, a multi-frequency portable instrument (FDEM) and an airborne time-domain electromagnetic one (AEM), known for their very high and relatively low vertical resolution respectively, were used to collect data over a former wetland then reclaimed for agricultural purposes. Additional electrical resistivity tomography (ERT) data are used together with sediment core data to assess the effectiveness and accuracy of the contact-less methods. Results show that both FDEM and AEM are very effective in detecting the presence of the peat layer, despite its low thickness (<2 m) and the high electro-conductive subsoil because of saltwater contamination. However, the AEM method overestimated the peat thickness while the FDEM could accurately resolve the peat thickness even where the layer was thinner than 1 m. When compared to the electrical features extracted from the ERT, discrepancies are on average lower than 30%; when compared to the borehole data, discrepancies are on average slightly higher than 6%.

Do plankton reflect the environmental quality status? The case of a post-industrial Mediterranean Bay

While the effects of industrial contamination in coastal areas may persist for years in benthos communities, plankton should not show permanent impairments because of their high spatial dynamics, fast turnover times and pronounced seasonality. To test this hypothesis, in 2019 we conducted five surveys in the Bay of Pozzuoli (Gulf of Naples, Mediterranean Sea), in front of a dismissed steel factory and in the adjacent inshore coastal waters. High seasonal variability was observed for bacteria, phytoplankton and mesozooplankton, whereas plankton spatial gradients were relatively smooth during each survey. Plankton biomass and diversity did not reveal any effects of past industrial activities not even at the innermost stations of the Bay, which however showed some signals of present anthropogenic pressure. Hydrodynamic and morphological features likely play a prominent role in maintaining a relatively good status of the plankton of the Bay, which hints at the relevance of coastal circulation and meteorological dynamics to revitalize areas impacted by human activities.

Application of in situ Solid-Phase Microextraction on Mediterranean Sponges for Untargeted Exometabolome Screening and Environmental Monitoring

In marine ecosystems, sponges are ubiquitous sessile organisms that contain a wide range of specialized metabolites. These metabolites point to a diverse range of biochemical pathways. Some of these compounds are biomarkers that indicate the presence of bacteria that form symbiotic relationships with a host sponge (microsymbionts). Sponges hold considerable promise as bioindicators for seawater quality monitoring, as they are exposed to, and accumulate, significant levels of anthropogenic contamination in coastal areas. Solid-phase microextraction (SPME) is a low-invasive and non-exhaustive technique that combines sampling and extraction into a single step and offers the added benefit of biocompatible extraction phases. We used different types of SPME devices to extract exometabolites from sponges (genus: Sarcotragus) in situ. Following extraction, the samples were analyzed via GC- and LC-MS in order to verify the presence of compounds associated with quorum sensing, as well as to examine the metabolism of organic pollutants, such as monocyclic aromatic hydrocarbons (MAHs), polycyclic aromatic hydrocarbons (PAHs), pesticides, and other bioactive compounds in an untargeted format. As the results demonstrate, when the extracted metabolites are compared with the background controls, SPME offers a non-exhaustive approach that can be used in the field to discover novel metabolites deriving from complex holobionts such as marine sponges.

EVALUACIÓN DEL RIESGO GENERADO POR ESPECIES INVASORAS INTRODUCIDAS A TRAVÉS DEL AGUA DE LASTRE EN DOS PUERTOS DEL PACÍFICO COLOMBIANO

La Organización Marítima Internacional (OMI) ha establecido lineamientos para afrontar el problema de la contaminación biológica en las áreas costeras generada por el vector agua de lastre. Entre estos lineamientos, se han establecido varios modelos para evaluar el riesgo de introducción de especies en nuevas áreas, dentro de los que se consideran: la frecuencia de descarga (C1), los volúmenes de agua de lastre descargados en puerto (C2); y, la similitud ambiental entre el puerto de origen con el puerto receptor (C3). Tomando como base el modelo OMI y la información contenida en los formatos de Notificación del agua de lastre, los cuales son remitidos a la Dirección General Marítima en cumplimiento con lo descrito en la Resolución 477/2012, se estableció el nivel de riesgo para los puertos de Tumaco y Buenaventura. Durante el año 2015, el agua de lastre con mayor frecuencia de deslastre en el puerto de Tumaco provino de Long Beach (USA), con un porcentaje de 13.4% del total de descarga (C1). Para el puerto de Buenaventura, este porcentaje estuvo representado por aguas provenientes de Manta (Ecuador) y Puerto Caldera (Costa Rica), con porcentajes de 19,56% y 18,47%, respectivamente. Tumaco importó alrededor de 334.224,9 m3 de agua de lastre y Buenaventura cerca de 132.294 m3, lo que correspondió a 184 tanques descargados, provenientes de 30 puertos de origen (12 países), para Tumaco y 187 tanques procedentes de 16 puertos de origen (6 países), para Buenaventura (C2). En cuanto a la similitud ambiental (C3), se pudo deducir que San José-Guatemala (0.99) y Buenaventura-Colombia (0.99), presentaron mayor similitud con el puerto de Tumaco, seguidos por Talara-Perú (0.98), la Pampilla-Perú (0.89) y Los Ángeles-USA (0.89); mientras que para Buenaventura la mayor similitud la presentaron los puertos ubicados en Puerto Quetzal-Guatemala (0.99) y Caldera-Costa Rica (0.97).

INFORMATIONAL BALANCE METHOD FOR DISPERSIVE AND NON-DISPERSIVE REMOTE SENSING SIGNALS FOR DETECTING OIL CONTAMINATION OF SOIL IN COASTAL AREAS USING HYPERSPECTROMETERS

The article presents a method for the detection of soil oil contamination in coastal areas using onboard hyperspectrometers - the signals informational balance method of dispersive and non-dispersive probing, used respectively for basic and validation measurements. Remote sensing is a potentially promising method for detecting various types of coastal environment pollution, including pollution by petroleum hydrocarbons. The general principle of remote presentation is the obligatory carrying out of remotely validation obtained results. The principles and methods of carrying out validation measurements are diverse and can be classified according to the following features: 1) synchronization of basic and validation measurements; 2) autonomy validation measurements; 3) select the height of the validation measurements. The proposed method operational algorithm is described. A variant of joint and synchronous basic and validation measurements using a hyperspectrometer installed on a low-altitude aircraft is considered. The mathematical model of the used method is given. Based on the information balance condition, an expression is obtained for determining the signal-to-noise ratio in the system in order to further calculate the correlation between the narrow-band oil index and the broadband signature-based sign of the heavy metals anomalous concentration.

Modeling fall migration pathways and spatially identifying potential migratory hazards for the eastern monarch butterfly

Identifying core migratory pathways and associated threats is important for developing conservation priorities for declining migratory species, such as eastern monarch butterflies (Danaus plexippus L.). Characterization of monarch fall migration core pathways and annual variability was compared using kernel density estimation models (KDEMs) and MaxEnt ecological niche models. Potential anthropogenic hazards were identified across migratory pathways and related to conservation strategies. Journey North citizen scientist monarch overnight roost data from 2002 to 2016 were used to model the fall migration at 10 km spatial resolution with MaxEnt and KDEMs. Potential anthropogenic threats to the fall migration were spatially identified along core migratory routes. The KDEM migratory pathways best represented patterns of monarch movement towards overwintering locations. Migratory routes varied as much as 200 km from east to west in the southern Central Flyway, which was also the only area identified with monarch roadkill hotspots. Potential threats from mosquito adulticide ultra-low volume (ULV) spraying were concentrated along Eastern Flyway coastal areas. Potential nectar resource loss or contamination from high usage of glyphosate herbicide and neonicotinoid insecticides was greatest in the Midwest, within the core route of the Central Flyway. MaxEnt and KDEM were complementary in modeling monarch migratory pathways. Monarch roadkill estimation and mitigation strategies are most needed in the southern core migratory pathways through Texas and Mexico. High quality nectar resource enhancement could help to mitigate potential threats from mosquito ULV spraying and nectar resource loss or contamination in coastal areas and the Midwest, respectively.