Journal articles on the topic 'Mediterranean coastal river'
To see the other types of publications on this topic, follow the link: Mediterranean coastal river.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Mediterranean coastal river.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Herut, B., N. Kress, and H. Hornung. "Nutrient pollution at the lower reaches of Mediterranean coastal rivers in Israel." Water Science and Technology 42, no. 1-2 (July 1, 2000): 147–52. http://dx.doi.org/10.2166/wst.2000.0306.
Abstract:
This study represents the first attempt to evaluate the nutrient load introduced into the coastal waters by the rivers along the Mediterranean coast of Israel. Measurements of nutrient concentrations (phosphate, ammonium, nitrate, nitrite, silicic acid) at two or three stations along the lower river reaches (11 rivers) were carried out annually from 1990 up to 1998. Combining the nutrient concentrations with the monthly riverine discharges we assessed the nutrient load. In general, most of the coastal rivers contain high nutrient contamination level, compared to the criteria adopted by NOAA (USA) for coastal river estuaries. The high degree of contamination is attributed to extreme low natural flow combined with the discharge of domestic and industrial wastes, and with agriculture runoff. In terms of nutrient concentrations, the Kishon River is the most polluted, followed by the Soreq, Poleg and Alexander Rivers. The preliminary estimate is that the coastal rivers transport between ~2000 to 6000 tons of dissolved inorganic nitrogen (DIN) and between ~250–800 tons of dissolved inorganic phosphorus (DIP) to the sea. An additional 3500 and 3000 tons of DIN and DIP, respectively, are supplied through the Kishon River. The load of the Poleg River is unknown (no discharge data) but expected to be significant based on nutrient concentration measured. The total load of the coastal rivers constitutes a major component among the other land-base point sources such as the Gush Dan outfall. Our estimate probably represents minimal values, as it does not include diffused input of agricultural runoff nor the riverine particulate and dissolved organic nutrient loads (which are unknown).
2
Higueras, M., P. Kerhervé, A. Sanchez-Vidal, A. Calafat, W. Ludwig, M. Verdoit-Jarraya, S. Heussner, and M. Canals. "Biogeochemical characterization of the riverine organic matter transferred to the NW Mediterranean Sea." Biogeosciences Discussions 10, no. 8 (August 8, 2013): 13277–316. http://dx.doi.org/10.5194/bgd-10-13277-2013.
Abstract:
Abstract. A large amount of terrestrial organic matter is annually delivered by rivers to the continental shelf, where this material is either buried or transferred to the deep sea by hydrodynamic processes such as storms. The relative amount of terrestrial organic matter in the marine sediments is often determined by analyzing the stable isotopes (δ13C and δ15N) and the C / N ratio of organic matter because the various particulate organic matter (POM) sources have distinct isotopic compositions. With the objective to refine and better interpret POM sources in the marine environment, we have monthly characterized terrestrial POM delivered by eight rivers discharging to the NW Mediterranean Sea: Rhône, Hérault, Orb, Aude, Têt, Fluvià, Ter and Tordera rivers. These rivers were simultaneously sampled from November 2008 to December 2009 and the concentrations of total suspended matter (TSM), particulate organic carbon (POC) and nitrogen (PN), as well as their stable isotopic ratios (δ13C and δ15N) were determined. During the survey, three rainstorm events with winds coming from the E–NE and the S–SE impacted the NW Mediterranean. Depending on the direction of incoming winds, the fluvial response (amount of water discharge and TSM) was different. Rivers draining the Alps (Rhône River) and Central Massif (Hérault, Orb, and Aude rivers) were mostly impacted by rainstorms associated with winds coming from the S–SE, while rivers draining the Pyrenees (Têt, Fluvià, and Ter rivers) and the Montseny Massif (Tordera River) were impacted by rainstorms associated with winds coming from the E–NE. In addition, the spatial evolution of water discharges shows different hydrological regime of the Rhône River, with relatively constant and high water stages and TSM concentrations when compared to coastal rivers, characterized by long periods of low water stages. TSM concentrations are positively correlated to water discharges (high water flows resuspended riverbed sediments) but show an inverse relationship with POC and PN relative contents (mostly due to dilution and by low availability of light in river waters during flood events). TSM in most of the coastal rivers have in average 2.5–3 times higher POC and PN mean contents than the Rhône River (8.5% and 1.5%, respectively for coastal rivers against 3.6% and 0.5%, respectively for the Rhône River). This discrepancy may be caused by the long drought periods in small coastal Mediterranean watersheds that enhance the eutrophication in studied coastal rivers. The δ13C ratios of organic matter reflect also this discrepancy between high and low water stages with values ranging from −33.2‰ to −24.5‰. The enriched 13C values (−26.3 ± 0.4‰ for the Rhône River and −26.9 ± 1.2‰ for coastal rivers), measured during high water stages, express mostly a mixture of terrestrial source (plant remains and soils) whereas depleted 13C values (∼ −30‰) associated with low water stages exhibit a source with predominant freshwater algae. The high δ15N mean values (> 8‰) found in Têt, Ter and Tordera rivers underline the importance of denitrification processes as a consequence of the eutrophication and anthropogenic impact.
3
Higueras, M., P. Kerhervé, A. Sanchez-Vidal, A. Calafat, W. Ludwig, M. Verdoit-Jarraya, S. Heussner, and M. Canals. "Biogeochemical characterization of the riverine particulate organic matter transferred to the NW Mediterranean Sea." Biogeosciences 11, no. 1 (January 10, 2014): 157–72. http://dx.doi.org/10.5194/bg-11-157-2014.
Abstract:
Abstract. A large amount of terrestrial organic matter is annually delivered by rivers to the continental shelf, where this material is either degraded, buried or transferred to the deep sea by hydrodynamic processes such as storms. The relative amount of terrestrial organic matter in the marine sediments is often determined by analysing the stable isotopes (δ13C and δ15N) and the C / N ratio of organic matter because the various particulate organic matter (POM) sources have distinct isotopic compositions. With the objective to refine and better interpret POM sources in the marine environment, we have characterized monthly terrestrial POM delivered by eight rivers discharging to the NW Mediterranean Sea: the Rhône, Hérault, Orb, Aude, Têt, Fluvià, Ter and Tordera rivers. These rivers were simultaneously sampled from November 2008 to December 2009 and the concentrations of total suspended matter (TSM), particulate organic carbon (POC) and nitrogen (PN), as well as their stable isotopic ratios (δ13C and δ15N) were determined. During the survey, three rainstorm events with winds coming from the E–NE and the S–SE impacted the NW Mediterranean. Depending on the direction of incoming winds, the fluvial response (amount of water discharge and TSM) was different. Rivers draining the Alps (Rhône River) and Central Massif (Hérault, Orb, and Aude rivers) were mostly impacted by rainstorms associated with winds coming from the S–SE, while rivers draining the Pyrenees (Têt, Fluvià, and Ter rivers) and the Montseny Massif (Tordera River) were impacted by rainstorms associated with winds coming from the E–NE. In addition, the spatial evolution of water discharges shows a different hydrological regime of the Rhône River, with relatively constant and high water stages and TSM concentrations when compared to coastal rivers, characterized by long periods of low water stages. TSM concentrations are positively correlated to water discharges (high water flows resuspended riverbed sediments) but show an inverse relationship with POC and PN relative contents (mostly due to dilution and by low availability of light in river waters during flood events). TSM in most of the coastal rivers have on average 2.5–3 times higher POC and PN mean contents than the Rhône River (8.5 and 1.5%, respectively, for coastal rivers compared to 3.6 and 0.5%, respectively, for the Rhône River). This discrepancy may be caused by the long drought periods in small coastal Mediterranean watersheds that enhance the eutrophication in studied coastal rivers. The δ13C ratios of organic matter also reflect this discrepancy between high and low water stages with values ranging from −33.2 to −24.5‰. The enriched 13C values (−26.3 ± 0.4‰ for the Rhône River and −26.9 ± 1.2‰ for coastal rivers), measured during high water stages, express mostly a mixture of terrestrial source (plant remains and soils) whereas depleted 13C values (∼ −30‰) associated with low water stages exhibit a source with predominant freshwater algae. The high δ15N mean values (>8‰) found in Têt, Ter and Tordera rivers may underline the importance of denitrification processes as a consequence of the eutrophication and anthropogenic impact.
4
Salgado-Hernanz, Paula Maria, Aurore Regaudie-de-Gioux, David Antoine, and Gotzon Basterretxea. "Pelagic primary production in the coastal Mediterranean Sea: variability, trends, and contribution to basin-scale budgets." Biogeosciences 19, no. 1 (January 3, 2022): 47–69. http://dx.doi.org/10.5194/bg-19-47-2022.
Abstract:
Abstract. We estimated pelagic primary production (PP) in the coastal (<200 m depth) Mediterranean Sea from satellite-borne data, its contribution to basin-scale carbon fixation, its variability, and long-term trends during the period 2002–2016. Annual coastal PP was estimated at 0.041 Gt C, which approximately represents 12 % of total carbon fixation in the Mediterranean Sea. About 51 % of this production occurs in the eastern basin, whereas the western and Adriatic shelves contribute with ∼25 % each of total coastal production. Strong regional variability is revealed in coastal PP, from high-production areas (>300 g C m−2) associated with major river discharges to less productive provinces (<50 g C m−2) located in the southeastern Mediterranean. PP variability in the Mediterranean Sea is dominated by interannual variations, but a notable basin-scale decline (17 %) has been observed since 2012 concurring with a period of increasing sea surface temperatures in the Mediterranean Sea and positive North Atlantic Oscillation and Mediterranean Oscillation climate indices. Long-term trends in PP reveal slight declines in most coastal areas (−0.05 to −0.1 g C m−2 per decade) except in the Adriatic where PP increases at +0.1 g C m−2 per decade. Regionalization of coastal waters based on PP seasonal patterns reveals the importance of river effluents in determining PP in coastal waters that can regionally increase up to 5-fold. Our study provides insight into the contribution of coastal waters to basin-scale carbon balances in the Mediterranean Sea while highlighting the importance of the different temporal and spatial scales of variability.
5
Herut, B., H. Hornung, N. Kress, M. D. Krom, and M. Shirav. "Trace metals in sediments at the lower reaches of Mediterranean coastal rivers, Israel." Water Science and Technology 32, no. 9-10 (November 1, 1995): 239–46. http://dx.doi.org/10.2166/wst.1995.0690.
Abstract:
Concentrations of mercury, lead, copper, zinc, cadmium, iron and partially chromium, manganese, nickel and aluminium, were recorded in surface sediments at the lower reaches of 11 rivers from the Mediterranean coastal zone of Israel, during 1988-1993. Excluding the lower Kishon river, no major contamination was found at most of the stations when trace metal concentrations were normalized against iron concentrations (trace metal/iron ratios) and compared to levels recorded in stream sediments from the southern drainage basin of the Kishon river. Minor enrichments found in part of the rivers are attributed to land-based point sources of pollution. Variations in trace metal concentrations at the estuaries are related to high influx of fine-grained sediments transported by heavy floods during rainy winters, which later are resuspended and transported seaward by bottom currents.
6
Chapapria, Vicent J. de Esteban, J. Javier Diez Gonzalez, Miguel Arenillas Parra, and Rafael Cortes Gimeno. "COASTAL PROCESSES IN GUARDAMAR BAY (SPAIN)." Coastal Engineering Proceedings 1, no. 21 (January 29, 1988): 99. http://dx.doi.org/10.9753/icce.v21.99.
Abstract:
The surrounding coastal area of the Segura's River mouth has registered in the last years many erosion problems. It is one of the biggest coastal conjunct in the Spanish mediterranean coast. A whole of studies was carried out to determine littoral and coastal processes in this area.
7
Houri, Ahmad, and Saadieh W. El Jeblawi. "Water quality assessment of Lebanese coastal rivers during dry season and pollution load into the Mediterranean Sea." Journal of Water and Health 5, no. 4 (May 1, 2007): 615–23. http://dx.doi.org/10.2166/wh.2007.047.
Abstract:
The chemical and microbiological properties of Lebanese perennial coastal rivers were studied during the dry season extending from July to September 2004. The results indicate significant levels of pollution in all eight rivers. Although many physical and chemical variables were within WHO guidelines for drinking water, coliform levels were unacceptably high indicating pollution from untreated sewage. The most polluted rivers in most categories were the Abu Ali and Antelias. With the exception of bacterial and phosphate loadings, Awali River provides the highest amount of pollution to the Mediterranean mainly due to its high water flow, although it is one of the least polluted rivers. The urgent need for controlling wastewater dumping into river streams is emphasized. The data obtained should serve as a reference point to assess the efficiency of planned wastewater treatment plants.
8
Meslard, Florian, Yann Balouin, Nicolas Robin, and François Bourrin. "Assessing the Role of Extreme Mediterranean Events on Coastal River Outlet Dynamics." Water 14, no. 16 (August 9, 2022): 2463. http://dx.doi.org/10.3390/w14162463.
Abstract:
River mouths are highly dynamic environments responding very rapidly to changes in wave energy or river floods. While the morphological response during floods or during marine storm events has been widely documented in the literature, little is known about the mechanisms acting during the co-occurrence of fluvial and marine hazards. This concomitance of river flood and marine storm is quite common in the western Mediterranean Sea, and was the case for the Gloria event, considered to be the most extreme event in recent decades. During this event, monitoring of hydrodynamics and morphological evolution was implemented, making it possible to better understand the impact of concomitant marine storm and fluvial flood during an extreme meteorological event on spit breaching of a small Mediterranean river mouth. Monitoring using a combination of high-resolution hydrodynamic measurements, topographic and bathymetric surveys, and sediment cores was used before, during, and after the storm “Gloria”. The results suggest an amplification of the morphological impact of the events and a different morphogenic response than if each of the events had acted independently on the system. The marine storm, occurring first, weakened the spit and initiated its breaching, which was continued by the extreme fluvial flood, thus leading to the complete destruction of the mouth. The destruction of the spit acted as a sediment source for subaqueous large delta deposition amounting to 50% of the total volume. The contribution of the river, estimated at 30%, was quite low for an exceptional event, showing the importance of locating rainfall in a catchment area controlled by a dam. For this event, extreme morphological evolution was observed, as well as the importance of water levels in the river mouth, which probably increased flood hazards, demonstrating the importance of including the compounding effect of extreme coastal water levels in river flood risk management.
9
Cozzi, Stefano, Carles Ibáñez, Luminita Lazar, Patrick Raimbault, and Michele Giani. "Flow Regime and Nutrient-Loading Trends from the Largest South European Watersheds: Implications for the Productivity of Mediterranean and Black Sea’s Coastal Areas." Water 11, no. 1 (December 20, 2018): 1. http://dx.doi.org/10.3390/w11010001.
Abstract:
In the last century, large watersheds in Southern Europe have been impacted by a combination of anthropogenic and climatic pressures, which have rapidly evolved to change the ecological status of freshwater and coastal systems. A comparative analysis was performed for Ebro, Rhône, Po and Danube rivers, to investigate if they exhibited differential dynamics in hydrology and water quality that can be linked to specific human and natural forces acting at sub-continental scales. Flow regime series were analyzed from daily to multi-decadal scales, considering frequency distributions, trends (Mann–Kendall and Sen tests) and discontinuities (SRSD Method). River loads of suspended matter, nutrients and organic matter and the eutrophication potential of river nutrients were estimated to assess the impact of river loads on adjacent coastal areas. The decline of freshwater resources largely impacted the Ebro watershed on annual (−0.139 km3 yr−1) and seasonal (−0.4% yr−1) scales. In the other rivers, only spring–summer showed significant decreases of the runoff coupled to an exacerbated flow variability (0.1–0.3% yr−1), which suggested the presence of an enhanced regional climatic instability. Discontinuities in annual runoff series (every 20–30 years) indicated a similar long-term evolution of Rhône and Po rivers, differently from Ebro and Danube. Higher nutrient concentrations in the Ebro and Po (+50%) compared to Rhône and Danube and distinct stoichiometric nutrient ratios may exert specific impacts on the growth of plankton biomass in coastal areas. The overall decline of inorganic phosphorus in the Rhône and Po (since the 1980s) and the Ebro and Danube (since the 1990s) mitigated the eutrophication in coastal ecosystems inducing, however, a phase in which the role of organic phosphorus loads (Po > Danube > Rhône > Ebro) on coastal productivity could be more relevant. Overall, the study showed that the largest South European watersheds are differently impacted by anthropogenic and climatic forces and that this will influence their vulnerability to future changes of flow regime and water quality.
10
FREYHOF, JÖRG, MÜFIT ÖZULUĞ, CÜNEYT KAYA, ESRA BAYÇELEBI, and DAVUT TURAN. "Redescription of Alburnus kotschyi Steindachner, 1863, with comments on Alburnus sellal adanensis Battalgazi, 1944 (Teleostei: Leuciscidae)." Zootaxa 4382, no. 3 (February 21, 2018): 573. http://dx.doi.org/10.11646/zootaxa.4382.3.8.
Abstract:
Alburnus kotschyi is re-described and a neotype is designated. It is found in a small isolated coastal stream at Arsuz at the eastern Mediterranean coast as well as in the Ceyhan and Seyhan River drainages in southern Anatolia. Alburnus adanensis, from the Seyhan River, seems not to have been found again since its first description in 1944 and might be extinct.
11
KORMAS, K. AR, A. NICOLAIDOU, and M. THESSALOU-LEGAKI. "Variability of environmental factors of an eastern Mediterranean Sea river influenced coastal system." Mediterranean Marine Science 4, no. 1 (June 1, 2003): 67. http://dx.doi.org/10.12681/mms.242.
Abstract:
Spercheios River discharge rates of nutrients, suspended particulate matter (SPM) and particulate organic carbon (POC) and seawater concentrations of these parameters as well as chlorophyll a(chl a) were measured in the Maliakos Gulf, Greece, on a monthly basis between 1992-1993. From all the nutrients measured, silicate showed the highest discharge rates followed by nitrate, phosphate and nitrite. The river introduced significant amounts of SPM (8.5 – 35.5 Kg d -1 ) with very low POC content (<3%). Most of the variables measured showed no gradient from the river to the outer gulf, which could be attributed to fast mixing of the incoming water. However, chl a had higher concentrations in the inner (0.3 – 4.9 Μg l -1 ) and lower in the outer gulf (0.05 – 2.5 Μg l -1 ). It is suggested that the nutrients introduced by the river are consumed faster in the inner gulf and that a number of temporal streams and non-point sources at the periphery of the gulf prevent the formation of a gradient.
12
Kourafalou, V. H., and E. V. Stanev. "Modelling the impact of atmospheric and terrestrial inputs on the Black Sea coastal dynamics." Annales Geophysicae 19, no. 2 (February 28, 2001): 245–56. http://dx.doi.org/10.5194/angeo-19-245-2001.
Abstract:
Abstract. The dynamics on the North Western Shelf area of the Black Sea are examined, with an emphasis on the circulation induced by buoyancy due to the land drained fresh waters and by the interaction with the atmosphere, notably wind stress. A three-dimensional, multi-layer hydrodynamic model is employed with realistic topography and parameterisation of river plume physics. We focus on the seasonal patterns of transport of the river induced low-salinity waters within the Coastal Low Salinity Band and the conditions that influence their removal toward the shelf interior. The numerical simulations show that coastal circulation is greatly influenced by river runoff and especially in the case of the Danube, which is excessively high with monthly aver-aged values ranging from 5000 to 10000 m3 /s. A significant contribution of runoff comes from the neighbouring rivers. At the same time, the North Western Shelf is quite broad, so that the coastal dynamics are largely sheltered from the conditions in the deeper sea. Buoyancy due to river runoff thus dominates, creating a southward coastal current that is the predominant pathway for the land-drained inputs. As in all shelf areas, wind stress is a major circulation forcing mechanism and it modifies the buoyancy induced flow. It is shown that the seasonal variability in river runoff and wind stress, in combination with the shelf topography, determines the different pathways for the terrestrial inputs. Implications on the overall basin circulation are drawn, as the availability of low-salinity waters of river origin affects the upper Black Sea layer. Consequently, the formation of distinct water masses (such as the Cold Intermediate Layer) and the properties of the outflow toward the Mediterranean are also influenced.Key words. Oceanography: general (continental shelf processes; numerical modelling) – Oceanography: physical (air-sea interactions)
13
Belmar, Oscar, Carles Ibáñez, Ana Forner, and Nuno Caiola. "The Influence of Flow Regime on Ecological Quality, Bird Diversity, and Shellfish Fisheries in a Lowland Mediterranean River and Its Coastal Area." Water 11, no. 5 (May 1, 2019): 918. http://dx.doi.org/10.3390/w11050918.
Abstract:
Designing environmental flows in lowland river sections and estuaries is a challenge for researchers and managers, given their complexity and their importance, both for nature conservation and economy. The Ebro River and its delta belong to a Mediterranean area with marked anthropogenic pressures. This study presents an assessment of the relationships between mean flows (discharges) computed at different time scales and (i) ecological quality based on fish populations in the lower Ebro, (ii) bird populations, and (iii) two shellfish fishery species of socioeconomic importance (prawn, or Penaeus kerathurus, and mantis shrimp, or Squilla mantis). Daily discharge data from 2000 to 2015 were used for analyses. Mean annual discharge was able to explain the variation in fish-based ecological quality, and model performance increased when aquatic vegetation was incorporated. Our results indicate that a good ecological status cannot be reached only through changes on discharge, and that habitat characteristics, such as the coverage of macrophytes, must be taken into account. In addition, among the different bird groups identified in our study area, predators were related to river discharge. This was likely due to its influence on available resources. Finally, prawn and mantis shrimp productivity were influenced up to a certain degree by discharge and physicochemical variables, as inputs from rivers constitute major sources of nutrients in oligotrophic environments such as the Mediterranean Sea. Such outcomes allowed revisiting the environmental flow regimes designed for the study area, which provides information for water management in this or in other similar Mediterranean zones.
14
Inghilesi, R., L. Ottolenghi, A. Orasi, C. Pizzi, F. Bignami, and R. Santoleri. "Fate of river Tiber discharge investigated through numerical simulation and satellite monitoring." Ocean Science 8, no. 5 (September 18, 2012): 773–86. http://dx.doi.org/10.5194/os-8-773-2012.
Abstract:
Abstract. The aim of this study was to determine the dispersion of passive pollutants associated with the Tiber discharge into the Tyrrhenian Sea using numerical marine dispersion models and satellite data. Numerical results obtained in the simulation of realistic discharge episodes were compared with the corresponding evolution of the spatial distributions of MODIS diffuse light attenuation coefficient at 490 nm (K490), and the results were discussed with reference to the local climate and the seasonal sub-regional circulation regime. The numerical model used for the simulation of the sub-tidal circulation was a Mediterranean sub-regional scale implementation of the Princeton Ocean Model (POM), nested in the large-scale Mediterranean Forecasting System. The nesting method enabled the model to be applied to almost every area in the Mediterranean Sea and also to be used in seasons for which imposing climatological boundary conditions would have been questionable. Dynamical effects on coastal circulation and on water density due to the Tiber discharge were additionally accounted for in the oceanographic model by implementing the river estuary as a point source of a buoyant jet. A Lagrangian particle dispersion model fed with the POM current fields was then run in order to reproduce the effect of the turbulent transport of passive tracers mixed in the plume with the coastal flow. Two significant episodes of river discharge in both winter and summer conditions were discussed in this paper. It was found that the winter regime was characterized by the presence of a strong coastal jet flowing with the ambient current. In summer the prevailing wind regime induced coastal downwelling conditions, which tended to confine the riverine waters close to the shore. In such conditions sudden wind reversals due to local weather perturbations, causing moderate local upwelling, proved to be the only effective way to disperse the tracers offshore, moving the plume from the coast and detaching large pools of freshwater.
15
Inghilesi, R., L. Ottolenghi, A. Orasi, C. Pizzi, F. Bignami, and R. Santoleri. "Fate of river Tiber discharge investigated through numerical simulation and satellite monitoring." Ocean Science Discussions 9, no. 2 (April 12, 2012): 1599–649. http://dx.doi.org/10.5194/osd-9-1599-2012.
Abstract:
Abstract. The aim of this study was to determine the dispersion of passive pollutants associated with the Tiber discharge into the Tyrrhenian Sea using numerical marine dispersion models and satellite data. Numerical results obtained in the simulation of realistic discharge episodes were compared with the corresponding evolution of the spatial distributions of MODIS diffuse light attenuation coefficient at 490 nm (K490), and the results were discussed with reference to the local climate and the seasonal sub-regional circulation regime. The numerical model used for the simulation of the sub-tidal circulation was a Mediterranean sub-regional scale implementation of the Princeton Ocean Model (POM), nested in the large-scale Mediterranean Forecasting System. The nesting method enabled the model to be applied to almost every area in the Mediterranean Sea and also to be used in seasons for which imposing climatological boundary conditions would have been questionable. Dynamical effects on coastal circulation and on water density due to the Tiber discharge were additionally accounted for in the oceanographic model by implementing the river estuary as a point source of a buoyant jet. A Lagrangian particle dispersion model fed with the POM current fields was then run, in order to reproduce the effect of the turbulent transport of passive tracers mixed in the plume with the coastal flow. Two significant episodes of river discharge in both Winter and Summer conditions were discussed in this paper. It was found that the Winter regime was characterized by the presence of a strong coastal jet flowing with the ambient current. In Summer the prevailing wind regime induces coastal downwelling conditions, which tend to confine the riverine waters close to the shore. In such conditions sudden wind reversals due to local weather perturbations, causing strong local upwelling, proved to be an effective way to disperse the tracers offshore, moving the plume from the coast and detaching large pools of freshwater.
16
Shalem, Yehuda, Yoseph Yechieli, Barak Herut, and Yishai Weinstein. "Aquifer Response to Estuarine Stream Dynamics." Water 11, no. 8 (August 13, 2019): 1678. http://dx.doi.org/10.3390/w11081678.
Abstract:
While seawater intrusions are widely discussed, the salinization of coastal aquifers via narrow rivers is hardly documented. This study investigates groundwater dynamics in an aquifer next to an estuarine stream on the eastern Mediterranean coast. Groundwater levels and salinization patterns were examined as a response to dynamic changes in estuary water, both in low-and high-permeability aquifer units. In the high-permeability unit, the extent of salinization was relatively constant, reaching a distance of at least 80 m from the river, with no long-term changes in fresh-saline interface depth, indicating that the system is in a quasi-steady state. Groundwater salinity in the low-permeability unit showed frequent and large fluctuations (up to 36 and 22 at 5 and 20 m from the river, respectively). We suggest that the river may have a more immediate impact on a low-permeability than on a high-permeability aquifer. This is dependent on the history of seawater encroachments to the river, which are better preserved in the low-permeability unit, and on the hydrogeology of this unit, where sand lenses can serve as high-permeability conduits. However, this unit can efficiently prevent a large extent of salinization of the regional coastal aquifer by the estuary water.
17
Turconi, Laura, Barbara Bono, Francesco Faccini, and Fabio Luino. "Anthropic Constraint Dynamics in European Western Mediterranean Floodplains Related to Floods Events." Remote Sensing 15, no. 19 (October 1, 2023): 4798. http://dx.doi.org/10.3390/rs15194798.
Abstract:
Numerous riverbeds and floodplains in the Western Mediterranean Area (WMA) have been affected by anthropogenic modifications during the last centuries. In recent decades, an increase in floods in the coastal WMA has been observed. Variations in the rainfall regime and anthropisation have influenced the relevant geomorphological processes. The coastal floodplains analysed include those in Italy, France, and Spain. Geomorphological and land use changes that occurred in the last two centuries were examined using historical and recent maps, historical data, and European big data since the 1800s for 65 basins, for which over 670 flood events and more than 1300 victims were identified. Anthropogenic activities have changed the patterns of floodplains. In most cases, narrowing of the riverbeds, especially in the lower river sections, has been observed. The riverbeds have also changed from braided- to single-channel morphologies. GIS analysis shows reductions in the coastal watercourse widths ranging from 10% to 95%, with an average of 55%. Other changes are related to the deviation in the watercourses, with trends that did not respect the natural river flow. In some cases, the watercourses were covered and have vanished from recent maps. This aspect has reduced or eliminated the perception of the risk not only for the residents but also for land planners.
18
Dumoulin, J.-P., L. Pozzato, J. Rassman, F. Toussaint, M. Fontugne, N. Tisnérat-Laborde, L. Beck, et al. "Isotopic Signature (δ13C, ∆14C) of DIC in Sediment Pore Waters: An Example from the Rhone River Delta." Radiocarbon 60, no. 5 (October 2018): 1465–81. http://dx.doi.org/10.1017/rdc.2018.111.
Abstract:
ABSTRACTA better understanding of the dynamics of different particulate organic matter (OM) pools in the coastal carbon budget is a key issue for quantifying the role of the coastal ocean in the global carbon cycle. To elucidate the benthic component of this carbon cycle at the land-sea interface, we investigated the carbon isotope signatures (δ13C and ∆14C) in the sediment pore waters dissolved inorganic carbon (DIC) in addition to the sediment OM to constrain the origin of the OM mineralized in sediments. The study site is located at the outlet of the Rhône River (Mediterranean Sea), which was chosen because this river is one of the most nuclearized rivers in Europe and nuclear 14C can serve as a tracer to follow the fate of the OM discharged by the river to the coastal sea. The ∆14C results found in the pore waters DIC show a general offset between buried and mineralized OM following a preferential mineralization model of young and fresh particles. For example, we found that the sediment OM has values with a mean ∆14C=–33‰ at sampling stations near the river mouth whereas enriched ∆14C values around +523‰ and +667‰ respectively were found for the pore waters DIC. This indicates complete mineralization of a riverine fraction of OM enriched in 14C in the river conduit during in-stream photosynthesis. In shelf sediments, the ∆14C of pore waters DIC is slightly enriched (+57‰) with sediment OM reaching –570‰. A mixing model shows that particles mineralized near the river mouth are certainly of riverine phytoplanktonic origin whereas OM mineralized on the shelf is of marine origin. This work highlights the fact that pore waters provide additional information compared to sediments alone and it seems essential to work on both pools to study the carbon budget in river prodelta.
19
Dogan Saglamtimur, Neslihan, and Suleyman Tugrul. "Comparison of Offshore and River-Influenced Coastal Waters in the Eastern Mediterranean." Ekoloji 17, no. 68 (2008): 17–23. http://dx.doi.org/10.5053/ekoloji.2008.683.
20
FREYHOF, JÖRG, and DAVUT TURAN. "Alburnus magnificus, a new species of bleak from the Orontes River drainage (Teleostei: Leuciscidae)." Zootaxa 4559, no. 2 (February 20, 2019): 373. http://dx.doi.org/10.11646/zootaxa.4559.2.10.
Abstract:
Alburnus magnificus, new species, is described from the northern Orontes River drainage in the eastern Mediterranean Sea basin. It is most similar and closely-related to A. qalilus from coastal rivers in Syria south of the Orontes. Alburnus magnificus is distinguished from A. qalilus by having the anal-fin origin below or behind the vertical through the last dorsal-fin ray, 4–5 scale rows between the lateral line and the anal-fin origin, and a flank pattern of bold black, grey or brown scales on a silvery or brown background. The two species are also distinguished by a minimum K2P distance of 1.8% in their COI sequence data.
21
Soria, Juan, Rebeca Pérez, and Xavier Sòria-Pepinyà. "Mediterranean Coastal Lagoons Review: Sites to Visit before Disappearance." Journal of Marine Science and Engineering 10, no. 3 (March 1, 2022): 347. http://dx.doi.org/10.3390/jmse10030347.
Abstract:
Coastal lagoons are an established priority habitat in the European environment because of the biological communities that inhabit them. Their origin is related to the transport of sediments from a nearby river or the movement of sands by the marine currents that produce the closure of a gulf. Therefore, they are recent geological formations, which also disappear quickly if environmental conditions change. The 37 coastal lagoons with a surface area greater than 10 km2 located in the Mediterranean basin have been identified. Fishing has been the traditional use of these lagoons, in addition to their use as a navigation harbor when they are open to the sea. Pollution, quality problems and their consequences are the most studied topics in recent publications. Sentinel-2 images taken in the summer of 2020 have been used to study water transparency, suspended matter and chlorophyll a concentration. The result was that only six of them are in good ecological condition, but most of them are eutrophic due to the impacts on their environment and the inflow of poor quality water. The cultural values of these lagoons must also be protected and preserved.
22
Molina, Rosa, Giorgio Anfuso, Giorgio Manno, and F. Javier Gracia Prieto. "The Mediterranean Coast of Andalusia (Spain): Medium-Term Evolution and Impacts of Coastal Structures." Sustainability 11, no. 13 (June 27, 2019): 3539. http://dx.doi.org/10.3390/su11133539.
Abstract:
This paper shows coastal evolution along the Andalusia Region (Spain) and the impacts on it of coastal structures. The study area was divided into 47 units to calculate the erosion/accretion/stability (or evolution) rates by using the DSAS extension of ArcGIS software. Evolution rates were divided into different classes from “Very high accretion” to “Very high erosion”. As a result, 9 units recorded accretion, 19 stability and 19 erosion. Further, 17 units presented a positive balance and 28 units a negative one, showing a negative net balance of 29,738.4 m2/year corresponding to the loss of 1784.30 km2 of beach surface in the 1956–2016 period. The distribution of evolution areas along the studied coast was carried out by means of the “R” project for statistical computing. The analysis evidenced the impact of rigid structures: accretion was essentially observed up-drift of ports and groins and in correspondence of protection structures, especially of breakwaters. Erosion classes were observed down-drift of ports and groins and in correspondence of revetments/seawalls, and at largest river deltas, and “stability” was observed at pocket beaches and coastal areas locally stabilized by protection structures. Last, results were used to determine the distribution of swash- and drift-aligned coastal sectors and main direction of sedimentary transport.
23
Ibáñez, Carles, Nuno Caiola, and Oscar Belmar. "Environmental Flows in the Lower Ebro River and Delta: Current Status and Guidelines for a Holistic Approach." Water 12, no. 10 (September 24, 2020): 2670. http://dx.doi.org/10.3390/w12102670.
Abstract:
Deltas are a particular type of estuarine system in which the dependence on river flow (water, sediments and nutrients) is very strong, especially in river-dominated deltas such as the Mediterranean ones, but environmental flow (e-flow) proposals for deltaic systems are scarce. The Ebro Delta is one of the largest wetland areas in the western Mediterranean and one of the most important estuarine systems in Europe. The aim of this paper is to review the state of the art regarding e-flows and to carry out a critical analysis of the proposals for the lower Ebro River and Delta, in order to highlight the possible environmental and socioeconomic impacts arising from the e-flow regime currently approved. Additionally, based on existing scientific information, methods to establish an e-flow regime that allows the maintenance of the main socio-ecological functions and values are discussed; including those functions and values for which not enough information is available. The study concludes that the currently approved e-flows are not suitable for maintaining most functions and values, as they would not prevent the proliferation of alien fish species and macrophytes in the river, the intrusion of the salt wedge in the estuary, the deficit of sediment/nutrient transport and the degradation of riparian habitats or the decline of coastal fisheries. Socioeconomic consequences on coastal fisheries, river navigation, salt water intrusion, sediment deficit, biodiversity, water quality, aquaculture and hydropower are also considered. Other e-flow proposals such as the proposed by the Catalan government would be more suitable to maintain the main socioecological functions and values of the lower Ebro River and Delta. Nevertheless, additional studies are needed to validate e-flows in some relevant aspects such as the capacity of the river to transport sediments to the delta to avoid coastal regression and mitigate the effects of sea level rise and subsidence, as well as the capacity of floods to control the spread of macrophytes. The lower Ebro River and delta is among the case studies where more quantitative and qualitative criteria to set e-flows with a holistic approach have been established.
24
Rodríguez-Santalla, Inmaculada, and Nuria Navarro. "Main Threats in Mediterranean Coastal Wetlands. The Ebro Delta Case." Journal of Marine Science and Engineering 9, no. 11 (October 27, 2021): 1190. http://dx.doi.org/10.3390/jmse9111190.
Abstract:
Coastal wetlands are dynamic ecosystems that exist at the interface between land and sea. They represent environments with a great diversity of habitats and communities, high carbon sequestration capacity and a wide range of ecosystem services. In the Mediterranean, the largest coastal wetlands are found in deltaic areas like that of the Ebro River (Spain), which has a coastline length of approximately 50 km, occupying a total area of 325 km2. The Ebro Delta is included in different national and international frameworks for environmental conservation, despite which there are several risks that threaten it. The lack of sedimentary contributions due to the regulation of the Ebro riverbed (irrigation, reservoirs, and hydroelectric power generation) has caused erosion and the retreat of certain sections of its coastline. To this situation of sediment deficit must be added the threat posed by the effects of global change, such as the rise in sea level, the increase in temperature and in the frequency and intensity of storms. This study analyses the particularities of the coastal wetland of the Ebro Delta, identifying the main threats it faces, as well as possible adaptation and mitigation strategies to these changes.
25
Melki, Samira, Salima Dakhli, Sarra Hechmi, and Moncef Gueddari. "River nutrient inflows and coastal ecosystem health in Northeast Tunisia's Kelibia Mediterranean Region." Regional Studies in Marine Science 71 (April 2024): 103410. http://dx.doi.org/10.1016/j.rsma.2024.103410.
26
Lattaud, Julie, Denise Dorhout, Hartmut Schulz, Isla S. Castañeda, Enno Schefuß, Jaap S. Sinninghe Damsté, and Stefan Schouten. "The C<sub>32</sub> alkane-1,15-diol as a proxy of late Quaternary riverine input in coastal margins." Climate of the Past 13, no. 8 (August 22, 2017): 1049–61. http://dx.doi.org/10.5194/cp-13-1049-2017.
Abstract:
Abstract. The study of past sedimentary records from coastal margins allows us to reconstruct variations in terrestrial input into the marine realm and to gain insight into continental climatic variability. There are numerous organic proxies for tracing terrestrial input into marine environments but none that strictly reflect the input of river-produced organic matter. Here, we test the fractional abundance of the C32 alkane 1,15-diol relative to all 1,13- and 1,15-long-chain diols (FC32 1, 15) as a tracer of input of river-produced organic matter in the marine realm in surface and Quaternary (0–45 ka) sediments on the shelf off the Zambezi and nearby smaller rivers in the Mozambique Channel (western Indian Ocean). A Quaternary (0–22 ka) sediment record off the Nile River mouth in the eastern Mediterranean was also studied for long-chain diols. For the Mozambique Channel, surface sediments of sites most proximal to Mozambique rivers showed the highest F1, 15 − C32 (up to 10 %). The sedimentary record shows high (15–35 %) pre-Holocene F1, 15 − C32 and low (< 10 %) Holocene F1, 15 − C32 values, with a major decrease between 18 and 12 ka. F1, 15 − C32 is significantly correlated (r2 = 0.83, p < 0.001) with the branched and isoprenoid tetraether (BIT) index, a proxy for the input of soil and river-produced organic matter in the marine environment, which declines from 0.25 to 0.60 for the pre-Holocene to < 0.10 for the Holocene. This decrease in both FC32 1, 15 and the BIT is interpreted to be mainly due to rising sea level, which caused the Zambezi River mouth to become more distal to our study site, thereby decreasing riverine input at the core location. Some small discrepancies are observed between the records of the BIT index and FC32 1, 15 for Heinrich Event 1 (H1) and the Younger Dryas (YD), which may be explained by a change in soil sources in the catchment area rather than a change in river influx. Like for the Mozambique Channel, a significant correlation between FC32 1, 15 and the BIT index (r2 = 0.38, p < 0.001) is observed for the eastern Mediterranean Nile record. Here also, the BIT index and FC32 1, 15 are lower in the Holocene than in the pre-Holocene, which is likely due to the sea level rise. In general, the differences between the BIT index and FC32 1, 15 eastern Mediterranean Nile records can be explained by the fact that the BIT index is not only affected by riverine runoff but also by vegetation cover with increasing cover leading to lower soil erosion. Our results confirm that FC32 1, 15 is a complementary proxy for tracing riverine input of organic matter into marine shelf settings, and, in comparison with other proxies, it seems not to be affected by soil and vegetation changes in the catchment area.
27
Lassaletta, L., E. Romero, G. Billen, J. Garnier, H. García-Gómez, and J. V. Rovira. "Spatialized N budgets in a large agricultural Mediterranean watershed: high loading and low transfer." Biogeosciences Discussions 8, no. 4 (August 29, 2011): 8723–59. http://dx.doi.org/10.5194/bgd-8-8723-2011.
Abstract:
Abstract. Despite the particular management practices and climate characteristics of the Mediterranean regions, the literature dealing with N budgets in large catchments subjected to Mediterranean conditions is scarce. The present study aims to deepen our knowledge on the N cycle within the Ebro River Basin (NE Spain) by means of two different approaches: (1) calculating a global N budget in the Ebro River Basin and (2) calculating a series of detailed regional budgets at higher geographical resolution. N inputs and outputs were spatialized by creating a map based on the most detailed information available. Fluvial and atmospheric N export was estimated together with N retention. The Ebro River Basin annually receives a relatively high amount of new N (5118 kg N km−2 yr−1), mostly in the form of synthetic fertilizers (50 %). Although it is a highly productive catchment, the net N input as food and feed import is also high (33 %). Only 8 % of this N is finally exported to the delta zone. Several territorial units characterized by different predominant uses (rainfed agriculture, irrigated agriculture and pastures) have differentiated N dynamics. However, due to the high density of irrigation channels and reservoirs that characterize Mediterranean basins, N retention is very high in all of them (median value, 92 %). These results indicate that problems of eutrophication due to N delivery in the coastal area may not be too severe but that high N retention values may instead lead to problems within the catchment, such as pollution of aquifers and rivers, as well as high atmospheric emissions. The most promising management measures are those devoted to reducing agricultural surpluses such as balanced N fertilization and low N livestock feeding.
28
Lassaletta, L., E. Romero, G. Billen, J. Garnier, H. García-Gómez, and J. V. Rovira. "Spatialized N budgets in a large agricultural Mediterranean watershed: high loading and low transfer." Biogeosciences 9, no. 1 (January 4, 2012): 57–70. http://dx.doi.org/10.5194/bg-9-57-2012.
Abstract:
Abstract. Despite the particular management practices and climate characteristics of the Mediterranean regions, the literature dealing with N budgets in large catchments subjected to Mediterranean conditions is scarce. The present study aims to deepen our knowledge on the N cycle within the Ebro River Basin (NE Spain) by means of two different approaches: (1) calculating a global N budget in the Ebro River Basin and (2) calculating a series of detailed regional budgets at higher geographical resolution. N inputs and outputs were spatialized by creating a map based on the most detailed information available. Fluvial and atmospheric N export was estimated together with N retention. The Ebro River Basin annually receives a relatively high amount of new N (5118 kg N km−2 yr−1), mostly in the form of synthetic fertilizers (50%). Although it is a highly productive catchment, the net N input as food and feed import is also high (33%). Only 8% of this N is finally exported to the delta zone. Several territorial units characterized by different predominant uses (rainfed agriculture, irrigated agriculture and pastures) have differentiated N dynamics. However, due to the high density of irrigation channels and reservoirs that characterize Mediterranean catchments, N retention is very high in all of them (median value, 91%). These results indicate that problems of eutrophication due to N delivery in the coastal area may not be too severe but that high N retention values may instead lead to problems within the catchment, such as pollution of aquifers and rivers, as well as high atmospheric emissions. The most promising management measures are those devoted to reducing agricultural surpluses through a better balanced N fertilization.
29
Vera-Herrera, Lucía, Susana Romo, and Juan Soria. "How Agriculture, Connectivity and Water Management Can Affect Water Quality of a Mediterranean Coastal Wetland." Agronomy 12, no. 2 (February 16, 2022): 486. http://dx.doi.org/10.3390/agronomy12020486.
Abstract:
The Natural Park of Albufera (Valencia, Spain) is an important Mediterranean coastal wetland that suffers continuous environmental effects from human activities and water uses, mainly related to agriculture and urban/industrial sewage discharges. The aim of this research was to assess the water quality of the different aquatic environments of this wetland, taking into account the connection between them, the agricultural impact and the management of irrigation water. The UE Water Framework Directive was followed in order to evaluate the ecological and trophic status of water systems. Spatial approaches were used to integrate physicochemical data into GIS vector layers to map the more problematic points of pollution. The results showed a globally eutrophic system with poor ecological potential. The wetland is nutrient-overloaded during the entire rice cultivation period. Good-quality water inputs are deficient, since the river network already has high levels of nutrients and pollutants, especially in the northern area, where river water is mixed with inappropriate effluents from wastewater treatment plants. Agriculture and water management affected the area intensively up to the Albufera lake, modulating most of the studied variables. The information gathered here can help to optimize the global study and management of the coastal Mediterranean wetlands, which are highly linked to agriculture.
30
Conejo-Orosa, Teresa, Antonio Román Muñoz, Isabel Reche, Jorge J. Montes-Pérez, Sofía Rodríguez-Gómez, and Enrique Moreno-Ostos. "Exploring NAO influence on waterbirds abundance through hydrological changes in a Mediterranean coastal wetland." Limnetica 43, no. 2 (October 6, 2023): 1. http://dx.doi.org/10.23818/limn.43.21.
Abstract:
Predicting how waterbird populations may respond to climate change is a major challenge for conservation, which could be addressed by understanding the effects of large-scale climate oscillations, such as the North Atlantic Oscillation (NAO), on breeding population size. Here, we explore the relationship between the NAO position and the abundance of waterbird breeding pairs in a protected Mediterranean coastal wetland (Mouth of the Guadalhorce River, Málaga, southern Iberian Peninsula). We found a significant and negative relationship between the winter NAO index and the abundance of grebes (r=-0.72, N=15, p<0.01), rails (r=-0.74, N=15, p<0.01), diving ducks (r=-0.56, N=15, p<0.05) and dabbling ducks (r=-0.54, N=15, p<0.05). Our results suggest that this relation is mediated by the NAO indirect effects on wetland flooded surface via changes in winter precipitation and Mediterranean sea level. These results should be considered to design appropriate environmental management strategies devoted to preventing or mitigating potential deleterious effects of the NAO variability on Mediterranean wetlands ecosystems and preserving their valuable waterbird communities.
31
PITTA, E., C. ZERI, M. TZORTZIOU, E. DIMITRIOU, V. PARASKEVOPOULOU, E. DASSENAKIS, M. SCOULLOS, and E. ANAGNOSTOU. "Dissolved organic matter cycling in eastern Mediterranean rivers experiencing multiple pressures. The case of the trans-boundary Evros River." Mediterranean Marine Science 15, no. 2 (July 1, 2014): 398. http://dx.doi.org/10.12681/mms.565.
Abstract:
The objective of our study was to provide a comprehensive evaluation on C, N, P cycling in medium sized Mediterranean rivers, such as the Evros, experiencing multiple pressures (intensive agriculture, industrial activities, population density). Our work aims also to contribute to the development of integrated management policies. Dissolved organic matter (DOM) cycling were investigated, during a one-year study. It was shown that the organic component of N and P was comparable to those of large Mediterranean rivers (Rhone, Po). In the lower parts of the river where all point and non-point inputs converge, the high inorganic N input favour elevated assimilation rates by phytoplankton and result in increased chl-a concentrations and autochthonous dissolved organic matter (DOM) production during the dry season with limited water flow. Moreover, carbohydrate distribution revealed that there is a constant background of soil derived mono-saccharides on top of which are superimposed impulses of poly-saccharides during blooms. During the dry season, inorganic nutrients and DOM are trapped in the lower parts of the river, whereas during high flow conditions DOM is flushed towards the sea and organic nitrogen forms can become an important TDN constituent (at least 40%) transported to shelf waters. The co-existence of terrigenous material with autochthonous and some anthropogenic is supported by the relatively low DOC:DON and DOC:DOP ratios, the positive correlation of DOC vs chl-a and the decoupling between DOC and DON. Overall, this study showed that in medium size Mediterranean rivers, such as the Evros, intensive agriculture and pollution sources in combination with water management practices and climatic variability are important factors determining C, N, P dynamics and export to coastal seas. Also, it highlights the importance of the organic fraction of N and P when considering management practices.
32
Harmelin–Vivien, M. L., D. Bǎnaru, J. Dierking, R. Hermand, Y. Letourneur, and C. Salen-Picard. "Linking benthic biodiversity to the functioning of coastal ecosystems subjected to river runoff (NW Mediterranean)." Animal Biodiversity and Conservation 32, no. 2 (2009): 135–45. http://dx.doi.org/10.32800/abc.2009.32.0135.
Abstract:
Continental particulate organic matter (POM) plays a major role in the functioning of coastal marine ecosystems as a disturbance as well as an input of nutrients. Relationships linking continental inputs from the Rhone River to biodiversity of the coastal benthic ecosystem and fishery production were investigated in the Golfe du Lion (NW Mediterranean Sea). Macrobenthic community diversity decreased when continen¬tal inputs of organic matter increased, whereas ecosystem production, measured by common sole (Solea solea) fishery yields in the area, increased. Decreases in macrobenthic diversity were mainly related to an increasing abundance of species with specific functional traits, particularly deposit-feeding polychaetes. The decrease in macrobenthic diversity did not result in a decrease, but an increase in ecosystem production, as it enhanced the transfer of continental POM into marine food webs. The present study showed that it is necessary to consider functional traits of species, direct and indirect links between species, and feedback loops to understand the effects of biodiversity on ecosystem functioning and productivity.
33
Barinova, Sophia, Moti Tavassi, and Eviatar Nevo. "Algal communities of the Hadera River (Israel) under dramatic niche changes." Open Life Sciences 5, no. 4 (August 1, 2010): 507–21. http://dx.doi.org/10.2478/s11535-010-0033-1.
Abstract:
AbstractThe Hadera River is the most polluted among the Mediterranean coastal rivers of Israel due to abundant E. coli, high concentrations of heavy metals and nutrients, and high temperatures. In 2003–2008 we found 191 species of algae and cyanobacteria belonging to seven taxonomic divisions. The upper reaches were dominated by cyanobacteria and exhibited levels of toxic pollution. Downstream, the ecological niches of algal communities dramatically changed: upper stream diversity first increased and then decreased due to the influx of rainwater in the tidal zone during winter. On one hand, seasonal dynamics show that in winter, inorganic contamination was reduced because of dilution by the influx of rainwater, but, on the other hand, organic pollution increased from agriculture. Down the river, diversity increases and the community composition undergoes considerable change. In summer, algal blooms indicate a reduction of stress and aid in the river’s self-purification. The WESI indices and RPI show steady year-round stressful conditions for algal photosynthesis with increasing instability in the river. Perpetuation of the current situation would disturb the self-purification capacity of the river ecosystem through destruction of biotic components. Statistical analysis (CCA) reveals the impact of wastewater as the most important stress factor for the Hadera River ecosystem, which is an exceptionally strong example of self-purification.
34
Sani, Teresa, Mauro Marini, Alessandra Campanelli, Mariana Machado Toffolo, Stefano Goffredo, and Federica Grilli. "Evolution of Freshwater Runoff in the Western Adriatic Sea over the Last Century." Environments 11, no. 1 (January 20, 2024): 22. http://dx.doi.org/10.3390/environments11010022.
Abstract:
The evaluation of the hydrography and biogeochemistry of the Adriatic Sea over the last century was summarized in this review to point out any changes in river runoff and provide an overview of the cause and effect of these trends on marine ecosystems. Although several rivers flow into the Adriatic, the most affected area is the northern Adriatic, where the Po River loads into the basin half of the total freshwater input, carrying river runoff and causing algal blooms and hypoxia phenomena. These fresh waters of the northern Adriatic flow predominantly along the entire western side, reaching the southernmost part of the basin up to the Mediterranean Sea. Here, and in the whole basin, variations in river runoff and nutrient concentration have been observed through the years. Starting from 1960 until the end of the century, an increase in nutrient discharge and phytoplankton activity was reported, with negative repercussions on local fisheries, species richness, and recreational activities within the basin. However, a recent decrease in river inflow has been observed along the coastal belt, which can trigger negative consequences for the food web of the marine ecosystem. These trends, more broadly, corroborate the vulnerability of the Adriatic Sea and stress the importance of implementing strategies for the defense of the relevant ecosystems within its confines.
35
Cerralbo, P., M. Grifoll, J. Moré, M. Bravo, A. Sairouní Afif, and M. Espino. "Wind variability in a coastal area (Alfacs Bay, Ebro River delta)." Advances in Science and Research 12, no. 1 (March 3, 2015): 11–21. http://dx.doi.org/10.5194/asr-12-11-2015.
Abstract:
Abstract. Wind spatial heterogeneity in a coastal area (Alfacs Bay, northwestern Mediterranean Sea) is described using a set of observations and modelling results. Observations in three meteorological stations (during 2012–2013) along the coastline reveal that wind from the N–NW (strongest winds in the region) appears to be affected by the local orography promoting high wind variability on relatively short spatial scales (of the order of few kilometres). On the other hand, sea breezes in late spring and summer also show noticeable differences in both spatial distribution and duration. The importance of wind models' spatial resolution is also assessed, revealing that high resolution (= 3 km) substantially improves the results in comparison to coarse resolution (9 km). The highest-resolution model tested (400 m) also presents noticeable improvements during some events, showing spatial variability not revealed by coarser models. All these models are used to describe and understand the spatial variability of the typical wind events in the region. The results presented in this contribution should be considered on hydrodynamic, ecological and risk management investigations in coastal areas with complex orography.
36
Podda, Cinzia, Jacopo Culurgioni, Riccardo Diciotti, Francesco Palmas, Elsa Amilhat, Elisabeth Faliex, Fabien Morat, Nicola Fois, and Andrea Sabatini. "Exploring European Eel Anguilla anguilla (L.) Habitat Differences Using Otolith Analysis in Central-Western Mediterranean Rivers and Coastal Lagoons from Sardinia." Fishes 8, no. 8 (July 26, 2023): 386. http://dx.doi.org/10.3390/fishes8080386.
Abstract:
An otolith shape and morphometric analysis was performed on European eel (Anguilla anguilla) subpopulations from five rivers and three coastal lagoons of Sardinia (central-western Mediterranean) to assess the role of different habitats on otolith development. Sagittal otolith shape was described by 11 harmonics from elliptic Fourier descriptors. Comparisons among the harmonics were run through canonical discriminant analyses (CDAs). The CDA reclassification rate (75.7%) demonstrated a spatial environmental discrimination among local eel subpopulations of Sardinia. The Euclidean distance values demonstrated a dissimilarity between the river and lagoon groups. The form factor and roundness shape indices were significantly higher in the river group than in the lagoon group. The distances of the first three rings to the otolith core revealed site-specific otolith development. Moreover, the annual otolith growth rate was faster in the lagoon group than in the river group. The differences among the studied sites in terms of sagittal otolith shape could relate to changes in different local stocks potentially related to environmental peculiarities. Establishing a direct correlation between otolith morphology and environmental factors is challenging, and further studies are needed to investigate the relationship between habitat type/environmental variation and growth/body characteristics of eels. Nevertheless, the achieved results suggest that this method can be considered to be a valuable tool for studying the ontogeny of the European eel.
37
Ghsoub, Myriam, Milad Fakhri, Thierry Courp, Gaby Khalaf, Roselyne Buscail, and Wolfgang Ludwig. "River signature over coastal area (Eastern Mediterranean): Grain size and geochemical analyses of sediments." Regional Studies in Marine Science 35 (March 2020): 101169. http://dx.doi.org/10.1016/j.rsma.2020.101169.
38
Markogianni, Vassiliki, Ioanna Varkitzi, Kalliopi Pagou, Alexandra Pavlidou, and Elias Dimitriou. "Nutrient flows and related impacts between a Mediterranean river and the associated coastal area." Continental Shelf Research 134 (February 2017): 1–14. http://dx.doi.org/10.1016/j.csr.2016.12.014.
39
Sánchez-Gavilán, Irene, Esteban Ramírez, and Vicenta de la Fuente. "Bioactive Compounds in Salicornia patula Duval-Jouve: A Mediterranean Edible Euhalophyte." Foods 10, no. 2 (February 12, 2021): 410. http://dx.doi.org/10.3390/foods10020410.
Abstract:
Many halophytes have great nutritional and functional potential, providing chemical compounds with biological properties. Salicornia patula Duval-Jouve is a common euhalophyte from saline Mediterranean territories (Spain, Portugal, France, and Italy). In the present work we quantified for the first time the bioactive compounds in S. patula (total phenolic compounds and fatty acids), from Iberian Peninsula localities: littoral-coastal Tinto River basin areas (southwest Spain, the Huelva province), and mainland continental territories (northwest and central Spain, the Valladolid and Madrid provinces). Five phenolic acids including caffeic, coumaric, veratric, salicylic, and transcinnamic have been found with differences between mainland and coastal saltmarshes. S. patula contain four flavonoids: quercetin-3-O-rutinoside, kaempferol/luteolin, apigenin 7-glucoside, and pelargonidin-3-O-rutinoside. These last two glycosylated compounds are described for the first time in this genus of Chenopodiaceae. The fatty acid profile described in S. patula stems contains palmitic, oleic, and linoleic acids in high concentrations, while stearic and long-chain fatty acids were detected in low amounts. These new findings confirm that S. patula is a valuable source of bioactive compounds from Mediterranean area.
40
El-Gamal, Ayman A., Sherif H. Balbaa, Mohamed A. Rashed, and Ahmed S. Mansour. "Three Decades Monitoring of Shoreline Change Pattern of Damietta Promontory, Nile Delta, Egypt." Aquatic Science and Technology 8, no. 2 (May 25, 2020): 1. http://dx.doi.org/10.5296/ast.v8i2.17087.
Abstract:
The Nile Delta is located on the Egyptian Mediterranean coast extending along nearly 240 km from the east of Alexandria to Port Said. The coastal area of the Nile Delta Promontories has been suffering extensive erosion problem. This was achieved after the construction of many water regulation structures in Nile River as dams and barrages, particularly the Aswan High Dam. It has nearly stopped the sediment flux carried by the Nile River to the Delta. This process has caused the Mediterranean Sea to reshape the Nile Delta coastal area. In order to cease these problems several engineering hard structures have been built. These structures avoided in ceasing the problem in the site of construction but shifted the erosion problem to the adjacent sites. This study aimed to analyze the shoreline change pattern on the term of three decades during the period between 1985 to 2015 at the coastal strip of Damietta Promontory and the impact of these protective structures on the coastal area. This was accomplished by the automated delineation of the successive shorelines covering this period using remote sensing imagery. The shorelines were extracted using the MNDWI index. The extracted shorelines were manipulated through the Digital Shoreline Analysis System (DSAS) software. The shoreline change rates were compared with sediments grain size for the past thirty years, heavy minerals content and radioactivity of recent marine sediment samples collected from different locations of marine profiles over the study area. The study revealed that Damietta Promontory has suffered from erosion during the study period reached its maximum shoreline retreat at the eastern side, nearly – 43 m/y. The total cumulative shoreline regression during the study period at this area was 1311m. The relation between the shoreline change process (erosion or accretion) and the physical parameters of coastal sediment showed that; as erosion increases, the heavy minerals content and radioactivity increases, while the mean grain size decreases and vice versa.
41
Roca, Mar, Gabriel Navarro, Javier García-Sanabria, and Isabel Caballero. "Monitoring Sand Spit Variability Using Sentinel-2 and Google Earth Engine in a Mediterranean Estuary." Remote Sensing 14, no. 10 (May 12, 2022): 2345. http://dx.doi.org/10.3390/rs14102345.
Abstract:
Estuarine degradation is a major concern worldwide, and is rapidly increasing due to anthropogenic pressures. The Mediterranean Guadiaro estuary, located in San Roque (Cadiz, Spain), is an example of a highly modified estuary, showing severe negative effects of eutrophication episodes and beach erosion. The migration of its river mouth sand spit causes the closure of the estuary, resulting in serious water quality issues and flora and fauna mortality due to the lack of water renewal. With the aim of studying the Guadiaro estuary throughout a 4-year period (2017–2020), the Sentinel-2 A/B twin satellites of the Copernicus programme were used thanks to their 5-day and 10 m temporal and spatial resolution, respectively. Sea–land mapping was performed using the Normalized Difference Water Index (NDWI) in the Google Earth Engine (GEE) platform, selecting cloud-free Sentinel-2 Level 2A images and computing statistics. Results show a closure trend of the Guadiaro river mouth and no clear sand spit seasonal patterns. The study also reveals the potential of both Sentinel-2 and GEE for estuarine monitoring by means of an optimized processing workflow. This improvement will be useful for coastal management to ensure a continuous and detailed monitoring in the area, contributing to the development of early-warning tools, which can be helpful for supporting an ecosystem-based approach to coastal areas.
42
Mauchamp, André, Philippe Chauvelon, and Patrick Grillas. "Restoration of floodplain wetlands: Opening polders along a coastal river in Mediterranean France, Vistre marshes." Ecological Engineering 18, no. 5 (June 2002): 619–32. http://dx.doi.org/10.1016/s0925-8574(02)00024-1.
43
Carmona, P., and J. M. Ruiz. "Historical morphogenesis of the Turia River coastal flood plain in the Mediterranean littoral of Spain." CATENA 86, no. 3 (September 2011): 139–49. http://dx.doi.org/10.1016/j.catena.2010.12.006.
44
Rovira, A., R. J. Batalla, and M. Sala. "Fluvial sediment budget of a Mediterranean river: the lower Tordera (Catalan Coastal Ranges, NE Spain)." CATENA 60, no. 1 (February 2005): 19–42. http://dx.doi.org/10.1016/j.catena.2004.11.001.
45
Reoyo-Prats, Brice, Dominique Aubert, Amélie Sellier, Benoit Roig, and Carmen Palacios. "Dynamics and sources of pharmaceutically active compounds in a coastal Mediterranean river during heavy rains." Environmental Science and Pollution Research 25, no. 7 (December 28, 2017): 6107–21. http://dx.doi.org/10.1007/s11356-017-0880-7.
46
Dufresne, Christiane, Bruno Arfib, Loïc Ducros, Céline Duffa, Frank Giner, and Vincent Rey. "Karst and urban flood-induced solid discharges in Mediterranean coastal rivers: The case study of Las River (SE France)." Journal of Hydrology 590 (November 2020): 125194. http://dx.doi.org/10.1016/j.jhydrol.2020.125194.
47
Marini, Mauro, and Federica Grilli. "The Role of Nitrogen and Phosphorus in Eutrophication of the Northern Adriatic Sea: History and Future Scenarios." Applied Sciences 13, no. 16 (August 15, 2023): 9267. http://dx.doi.org/10.3390/app13169267.
Abstract:
In the last two decades of the 21st century, a gradual decrease in nitrogen and phosphorus has been observed along the coastal area of the Northern Adriatic Sea. This depletion is attributed to reduced river flows. Studies conducted over the past four decades have indicated that the N/P ratio in the open sea is unlikely to undergo significant change. In fact, it tends to increase due to the unique characteristics of the Northern Adriatic Sea, which experiences slow water turnover and is influenced by strong winds. Additionally, the Northern Adriatic Sea receives a substantial amount of freshwater from rivers, accounting for about one-third of the total freshwater flow into the Mediterranean. These rivers carry nutrient loads that contribute to the high productivity and abundance of fish in this sea, making it one of the most productive areas in the Mediterranean. It has been observed that the cessation of anthropogenic phosphorus input, which has been regulated since the late 1980s with legislation limiting its use in detergents, has significantly affected the trophic chain. The aim of this review is to provide an overview of the eutrophication trend in the Northern Adriatic Sea, highlighting the importance long-term data series.
48
Giani, Michele, Nives Ogrinc, Samo Tamše, and Stefano Cozzi. "Elevated River Inputs of the Total Alkalinity and Dissolved Inorganic Carbon in the Northern Adriatic Sea." Water 15, no. 5 (February 25, 2023): 894. http://dx.doi.org/10.3390/w15050894.
Abstract:
The response of coastal systems to global acidification depends strongly on river inputs, which can alter the total alkalinity (AT) and dissolved inorganic carbon (DIC) in seawater. The northern Adriatic Sea (NAd) is a shallow continental shelf region that currently receives about 15% of the total freshwater input in the Mediterranean Sea, where the role of riverine discharges on the carbonate system has been poorly studied. In particular, river discharges can alter the carbonate system in the sea, affecting both the equilibrium chemistry and biological processes. For the main rivers flowing into the NAd (the Po, Adige, Brenta, Piave, Livenza, Tagliamento, Isonzo, Timavo and Rižana), data were collected for the pH, concentrations of the total alkalinity (AT), Ca2+ and Mg2+ and the isotopic ratio of stable carbon in the dissolved inorganic carbon (δ13CDIC). The DIC fluxes were estimated using the THINCARB (THermodynamic modeling of INOrganic CARBon) model for the compilation of the AT and pH data. The results show that the total transport of the AT in the rivers was 205 Gmol yr−1 while the transport of the DIC was 213 Gmol yr−1, of which about 70% was from the Po River. About 97% of the DIC in the river waters was in the form of bicarbonates. The high Mg2+/Ca2+ ratios indicate that dolomite weathering is predominant in the Adige, Piave, and Livenza river basins, while lower ratios in the Timavo and Rižana rivers indicate a greater proportion of calcite. The mean δ13C-DIC value was estimated to be −10.0 ± 1.7 ‰, a value nowadays considered typical for the DIC flux inputs in oceanic carbon cycle modeling. The DIC flux depends on the mineral weathering and biological activity in each river basin. However, these natural processes can be modified by anthropogenic disturbances that should be better quantified.
49
El Bakkali, Ayoub, Haitam Afilal, Abdellah Trankil, Halima Rezqi, Lhoussain Ed-Daoudy, and Abdelhamid Rossi. "Study of current benthic foraminifera as environmental bioindicators in the mediterranean coasts, northwest Morocco." E3S Web of Conferences 502 (2024): 01002. http://dx.doi.org/10.1051/e3sconf/202450201002.
Abstract:
In this project, we introduce a novel methodology for analysing the environmental conditions in the coastal area of Martil (Tétouan, Morocco) using benthic foraminifera as bio-indicators of marine ecological status. Benthic foraminifera have emerged as reliable indicators of environmental pollution, Their sensitivity to environmental changes, wide geographic presence, and short life cycle make them ideal for indicating the ecological status. Our study focused on the Mediterranean coastal region, along a radial perpendicular to the coast, at different depths, at the mouth of the Martil River, in addition to a control sample collected in the Azla region at a depth of 25 meters. Abiotic parameters like pH, temperature, and dissolved oxygen were measured on-site, complemented by detailed sedimentary analyses in the laboratory. A meticulous protocol was followed for the study of microfauna, particularly benthic foraminifera, involving washing, extraction, sorting, species identification, statistical counting, and microscopic imaging. Utilizing CA and AHC analyses, we identified factors influencing benthic foraminifera distribution, such as sediment depth and grain size variations. Specific indices derived from foraminifera data allowed us to assess stress levels accurately. This comprehensive approach provides valuable insights into evaluating the ecological health of Morocco's coastal marine ecosystems, paving the way for informed conservation efforts and sustainable management practices.
50
Sanuy, Marc, Tomeu Rigo, José A. Jiménez, and M. Carmen Llasat. "Classifying compound coastal storm and heavy rainfall events in the north-western Spanish Mediterranean." Hydrology and Earth System Sciences 25, no. 6 (July 1, 2021): 3759–81. http://dx.doi.org/10.5194/hess-25-3759-2021.
Abstract:
Abstract. The north-west (NW) Mediterranean coastal zone is a populous and well-developed area in which the impact of natural hazards like flash floods and coastal storms can result in frequent and significant damages. Although the occurrence and impacts of such hazards have been widely covered, few studies have considered their combined impact on the region, which would result in more damage. Within this context, this study analyses the occurrence and characteristics of compound extreme events of heavy rainfall episodes (as a proxy for flash floods) and coastal storms (using the maximum significant wave height) along the Catalan coast as a paradigm of the NW Mediterranean. Two different types of events are considered: multivariate, in which the two hazards occur at the same location, and spatially compounding, in which they occur within the same limited time window, and their impacts accumulate at distinct and separate locations. The analysis is regionally performed along a coastline extension of about 600 km by considering seven coastal sectors and their corresponding river catchment basins. Once the compound events are analysed, the synoptic atmospheric pressure fields are analysed to determine the prevailing weather conditions that generated them. Finally, a Bayesian network is used to fully characterize these events over the territory. The obtained results show that the NW Mediterranean, represented by the Catalan coast, has a high probability of experiencing compound extreme events. Despite the relatively small size of the study area, there are significant variations in the event characteristics along the territory, with the most frequent type being spatially compound, except in the northernmost sectors where multivariate events dominate. These northern sectors also present the highest correlation in the intensity of both hazards. Three representative synoptic situations have been identified as dominant for the occurrence of these events, with different relative importance levels of the compounding drivers (rainfall and waves) and different distributions of impacts across coastal basins. Overall, results obtained from specific events indicated that heavy rainfall is related to the most significant impacts despite having a larger spatial reach.