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Bioaccessibility of heavy metals and risk assessment in urban gardens of Madrid
2013
Ortega Romero, Marcelo Fabián | Mingot Marcilla, Juan | García Martínez, María Jesús | Miguel García, Eduardo de | Izquierdo, Miguel | Gómez, Amaya
Human health problems and solutions. Urban gardening has spread worldwide in recent years as it enhances food security and selfsupply and promotes community integration. However urban soils are significantly enriched in trace elements relative to background levels. Exposure to the soil in urban gardens may therefore result in adverse health effects depending on the degree of contact during gardening, infant recreational activities and ingestion of vegetables grown in them. In order to evaluate this potential risk, 36 composite samples were collected from the top 20 cm of the soil of 6 urban gardens in Madrid. The aqua regia (pseudototal) and glycine-extractable (bioaccessible) concentrations of Co, Cr, Cu, Ni, Pb and Zn were determined by atomic absorption spectrophotometry. Additionally, pH, texture, Fe, Ca, and Mn concentrations, and organic matter and calcium carbonate contents were determined in all urban gardens and their influence on trace element bioaccessibility was analyzed.
Показать больше [+] Меньше [-]Analysis of quaternary ammonium compounds in urban stormwater samples
2012
van de Voorde, A. | Lorgeoux, C. | Gromaire, Marie-Christine | Chebbo, G. | Laboratoire Eau, Environnement et Systèmes Urbains (LEESU) ; AgroParisTech-Université Paris-Est Marne-la-Vallée (UPEM)-École nationale des ponts et chaussées (ENPC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)
International audience | A method for benzalkonium analysis has been developed to measure benzalkonium concentration in dissolved and particulate fractions from urban runoff samples. The analysis was performed by liquid chromatography coupled with mass spectrometry (LC-MS/MS). The dissolved matrix was extracted by Solid Phase Extraction (SPE), with cationic exchange and the particles by microwave extraction with acidified methanol. Recovery percentages were closed to 100% for benzalkonium C12 and C14. The protocol was applied to roof runoff samples collected after a roof demossing treatment, and to separative stormwater samples from a 200 ha catchment. The results illustrate an important contamination of the roof runoff, with a maximum concentration close to 27 mg/L during the first rain. The benzalkonium concentration (sum of C12 and C14) stayed high (up to 1 mg/L) even 5 months after the treatment. Benzalkonium concentration measured in stormwaters was low (0.2 µg/L) but with contaminated suspended solids (up to 80 µg/g). © 2012 Elsevier Ltd. All rights reserved.
Показать больше [+] Меньше [-]Partial recovery of macrozoobenthos on the northwestern shelf of the Black Sea.
2024
Chevalier, Séverine | Beauchard, Olivier | Teacă, Adrian | Soetaert, Karline | Grégoire, Marilaure
peer reviewed | The northwestern shelf of the Black Sea has been affected by eutrophication and bottom hypoxia since the sixties. Consequently, the macrozoobenthos has suffered a well-established decline in biodiversity. However, the nature of the current benthic communities remains questionable. From 1995 to 2017, we compiled species and abiotic data for 138 sites over the shelf. Through an appropriate multivariate analytical approach, we identified benthic community changes solely due to organic pollution variations. Our results show signs of recovery with an increase in biodiversity and proportion of species vulnerable to organic enrichment. These changes were related to a decrease in riverine loads and subsequent eutrophication. However, some long-lived species typical of the area still did not exhibit noticeable recovery, which suggests that either the recovery process has not yet been achieved or some environmental conditions are still not met to warrant a sea floor ecosystem state substantially healthy. | 14. Life below water
Показать больше [+] Меньше [-]Nutrient enrichment and herbivory alter carbon balance in temperate seagrass communities
2024
Jiménez Ramos, Rocío | Brun Murillo, Fernando Guillermo | Vergara Oñate, Juan José | Hernández Carrero, Ignacio | Pérez Lloréns, José Lucas | Egea Tinoco, Luis Gonzalo | Biología
Large nutrient levels and herbivory stress, particularly when acting together, drive a variety of responses in seagrass communities that ultimately may weaken their carbon balance. An in situ three-months experiment was carried out in two contrasting seasons to address the effects of two levels of nutrient load and three levels of artificial clipping on Cymodocea nodosa plants. Nutrient enrichment shifted the community from autotrophic to heterotrophic and reduced DOC fluxes in winter, whereas enhanced community carbon metabolism and DOC fluxes in summer. Herbivory stress decreased the net primary production in both seasons, whereas net DOC release increased in winter but decreased in summer. A reduction of seagrass food-web structure was observed under both disturbances evidencing impacts on the seagrass ecosystems services by altering the carbon transfer process and the loss of superficial OC, which may finally weaken the blue carbon storage capacity of these communities.
Показать больше [+] Меньше [-]Optimizing phosphorus fertigation management zones using electromagnetic induction, soil properties, and crop yield data under semi-arid conditions.
2023
Chtouki, Mohamed | Nguyen, Frédéric | Garré, Sarah | Oukarroum, Abdallah
peer reviewed | The impact of climate change on water resource availability and soil quality is more and more emphasized under the Mediterranean basin, mostly characterized by drought and extreme weather conditions. The present study aims to investigate how electromagnetic induction technique and soil mapping combined with crop yield data can be used to optimize phosphorus (P) use efficiency by chickpea crop under drip fertigation system. The study was carried out on a 2.5-ha agricultural plot and the agronomic experiments in two growing cycles of chickpea crop. Soil spatial variability was first assessed by the measurement of soil apparent electrical conductivity (ECa) using the CMD Mini-Explorer sensor, and then, soil physicochemical properties were evaluated based on an oriented soil sampling scheme to explore other soil spatial variabilities influencing chickpea yield and quality. Data from the first agronomic experiment were used in geostatistical, multiple linear regression (MLR), and fuzzy c-means unsupervised classification algorithms to properly identify P drip fertigation management zones (MZs). Results from the Person's correlation analysis revealed that chickpea grain yield was more influenced by soil ECa (r = - 0.56), pH (r = - 0.84), ECe (r = - 0.6), P content (r = 0.72), and calcium (Ca) content (r = - 0.83). The proposed MLR-based model to predict chickpea grain yield showed good performances with a normalized root mean square error (NRMSE) of 0.11% and a coefficient of determination (R2) equal to 0.69. The identified MZs were verified by the one-way variance analysis for the studied soil and plant attributes, revealing that the first MZ1 presents a high grain yield, high soil P content, and low ECa. The low fertility MZ2 located in the south part of the studied site presented a low chickpea grain yield due to the low P content and the high ECa. Moreover, the application of P-variable rate fertigation regimes in the second field experiment significantly improved P use efficiency, chickpea grain yield, seed quality, and farmer income by 18%, 12%, 9%, and 136 $/ha, respectively, as compared to the conventional drip fertigation practices. The approach proposed in this study can greatly contribute to optimizing agro-input use efficiency under drip fertigation system, thereby improving farmers' incomes, preserving the ecosystem, and ensuring sustainable cropping systems in the Mediterranean climate.
Показать больше [+] Меньше [-]Artisanal trawl fisheries as a sentinel of marine litter pollution
2023
Viejo Marín, Josué | Cózar Cabañas, Andrés | Quintana Sepúlveda, Rocío | Martí Morales, Elisa | Markelain, Gorka | Cabrera Castro, Remedios | Muñoz Arroyo, Gonzalo | Montero, Enrique | Morales Caselles, María del Carmen | Biología
Systematic seafloor surveys are a highly desirable method of marine litter monitoring, but the high costs involved in seafloor sampling are not a trivial handicap. In the present work, we explore the opportunity provided by the artisanal trawling fisheries to obtain systematic data on marine litter in the Gulf of Cadiz between 2019 and 2021. We find that plastic was the most frequent material, with a prevalence of single-use and fishing-related items. Litter densities decreased with increasing distance to shore with a seasonal migration of the main litter hotspots. During pre-lockdown and post-lockdown stages derived from COVID-19, marine litter density decreased by 65 %, likely related to the decline in tourism and outdoor recreational activities. A continuous collaboration of 33 % of the local fleet would imply a removal of hundreds of thousands of items each year. The artisanal trawl fishing sector can play a unique role of monitoring marine litter on the seabed
Показать больше [+] Меньше [-]Assessment of elemental composition in commercial fish of the Bay of Cádiz, Southern Iberian Peninsula
2022
Calero Cano, Sandra | Donázar Aramendía, Íñigo | Morales, Emilio | Arechavala Lopez, Pablo | Cervera Currado, Juan Lucas | Guerra-Garcia, Jose Manuel | Giráldez, Inmaculada | Biología
The assessment of trace metal content in our fish diet is important due to the adverse effect on human health. Despite the increasing interest about the fish quality, little information is available for Southern Spain, a region characterized by high seafood intake. Nine species from the Bay of Cádiz with high commercial value were selected. Similar values were measured in the nine studied species for most of the elements, except for the macroelements Ca and S, and the microelements Fe, Mn and As, which showed significant differences among species. Metal Pollution Index (MPI) did not differ among species, and it was similar to those obtained for other Atlantic and Mediterranean locations. The values measured for the nine species were below the health limits provided by World, European and Spanish legislations, indicating that, in general terms, consumption of these species is safe in the study area. | 9 páginas
Показать больше [+] Меньше [-]Accumulation and distribution of microplastics in coastal sediments from the inner Oslofjord, Norway
2021
Bronzo, Laura | Lusher, Amy L. | Schøyen, Merete | Morigi, Caterina
Embargo until November 4 2023 | Microplastic presence in benthic marine systems is a widely discussed topic. The influence of the natural matrix on microplastic distribution within the sedimentary matrix is often overlooked. Marine sediments from the western inner Oslofjord, Norway, were investigated for temporal trends, with a particular focus on the relationship between sediment grain-sizes and microplastic distribution. Density separation, optical microscopy and chemical validation were used to categorize microplastics. Microplastic concentrations ranged from 0.02 to 1.71 MPs g −1 dry weight (dw). Fibres were the most common (76%), followed by fragments and films (18%, 6%). Common polymers were polyesters (50%), polypropylene (18%), polymethylmethacrylate (9%), rayon and viscose (5%) and elastane (4%). Microplastics appear to accumulate preferentially according to their morphology and polymer type in certain sediment grain-sizes. Microplastics inputs to the Oslofjord appear to derive from a wastewater treatment plant in the vicinity. Although, the redistribution of microplastics within the fjord needs further investigation. | acceptedVersion
Показать больше [+] Меньше [-]Microplastic pollution in the Weser estuary and the German North Sea
2021
Roscher, Lisa | Fehres, Annika | Reisel, Lorenz | Halbach, Maurits | Scholz-Böttcher, Barbara M. | Gerriets, Michaela | Badewien, Thomas | Shiravani, Gholamreza | Wurpts, Andreas | Primpke, Sebastian | Gerdts, Gunnar
Microplastics (MP) are defined as synthetic organic pollutants sized <5 mm and have been recorded in various environments worldwide. Due to their small size, they pose a potential risk for many organisms throughout the food web. However, little is known about MP distribution patterns and associated transport mechanisms. Rivers may act as pathways for MP into marine environments. In this study, we investigate the occurrence of MP in the estuary and lower stretch of the second-largest German River, the Weser, representative of a significant interface between fresh water and marine environments. The aim of the study was to enhance the general understanding by providing novel, comprehensive data and suggestions for future studies on estuarine systems. Surface water samples of two different size classes were collected by ship using an on-board filtration system (11-500 µm fraction) and net sampling (500-5000 µm fraction). After a thorough sample preparation, all samples were analysed with Focal Plane Array (FPA) Fourier Transform Infrared (FTIR) spectroscopy and Attenuated Total Reflection (ATR) FTIR spectroscopy in order to obtain information on MP concentrations, polymer composition and size distribution. Our findings show highest concentrations in the 11-500 µm fraction (2.3 × 101 − 9.7 × 103 m−3), with the polymer cluster acrylates/polyurethanes/varnish being dominant. The >500 µm fraction was dominated by polyethylene. Estimated MP concentrations generally increased in the Turbidity Maximum Zone (TMZ) and decreased towards the open sea. This study contributes to the current research by providing novel insights into the MP pollution of the estuary and lower stretch of an important European river and provides implications for future MP monitoring measures.
Показать больше [+] Меньше [-]Evaluation of a eukaryote phylogenetic microarray for environmental monitoring of marine sediments
2020
Lekang, Katrine | Lanzén, Anders | Jonassen, Inge | Thompson, Eric | Troedsson, Christofer
Increased exploitation of resources in sensitive marine ecosystems emphasizes the importance of knowledge regarding ecological impacts. However, current bio-monitoring practices are limited in terms of target-organisms and temporal resolution. Hence, developing new technologies is vital for enhanced ecosystem understanding. In this study, we have applied a prototype version of a phylogenetic microarray to assess the eukaryote community structures of marine sediments from an area with ongoing oil and gas drilling activity. The results were compared with data from both sequencing (metabarcoding) and morphology-based monitoring to evaluate whether microarrays were capable of detecting ecosystem disturbances. A significant correlation between microarray data and chemical pollution indicators, as well as sequencing-based results, was demonstrated, and several potential indicator organisms for pollution-associated parameters were identified, among them a large fraction of microorganisms not covered by traditional morphology-based monitoring. This suggests that microarrays have a potential in future environmental monitoring. | acceptedVersion
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