Limit Values of Dissolved Nutrients for the Assessment of Eutrophication in the Northeastern Mediterranean Rivers

Akçay, İsmail | Özbay, Özgür

This study attempted to determine the limit values of dissolved nutrients for assessing trophic status and water quality of Northeastern Mediterranean Rivers from the previously published nutrient data sets. Study findings indicated that the oligotrophic river waters should have concentrations of total phosphorus, orthophosphate, ammonium and total nitrogen less than 0.13 mg/L, 0.07 mg/L, 0.11 mg/L and 0.90 mg/L, respectively. The proposed limit values defining oligotrophy, mesotrophy and eutrophy differed from those reported by the Surface Water Quality Regulation and the commonly used reference values. These discrepancies were probably due to the rivers' distinct physical and biochemical characteristics. New approaches, such as modeling studies, are needed to define threshold and referen...

Ecological and Health Risk Assessment in Surface Sediments of the Berdan River Basin (Mersin-Türkiye)

Akçay, İsmail | Özbay, Özgür

Berdan River (Tarsus-Mersin) is one of the major rivers flowing into the coastal region of Northeastern (NE) Mediterranean Sea. Determination of water and sediment quality is of great importance for the sustainable management of streams and rivers. In this study, it was aimed to determine metal ((Fe), Manganese (Mn), Chromium (Cr), Nickel (Ni) Zinc (Zn), Cadmium (Cd) and Lead (Pb)) pollution status of sediments in Berdan River caused by human activities by using Enrichment Factor (EF), Geoaccumulation Index (Igeo), Contamination Factor (CF) and Pollution Load Index (PLI). Furthermore, the potential health risk assessment was determined as the non-carcinogenic and carcinogenic risk for children and adults by using chronic daily intake (CDI), hazard quotients (HQ), hazard index (HI), cancer ...

Metal pollution status and health risk assessment of beach sediments along the Mersin coast, Turkey

Özbay, Özgür | Akçay, İsmail

In the present study, the ecological risk assessment of metal contamination in beach sediments along the Mersin coast was determined using the metal contents of beach sediments in Mersin, Kızkalesi, Susanoğlu and Taşucu region obtained between 2006 and 2009. Furthermore, the potential health risk assessment for ingestion and dermal contact pathways of adults and children was determined. Ecological risk assessment of heavy metals showed that there is no pollution in the beach sediments for the metals Cu, Pb and Zn for the all studied coasts. However, the high ecological risk indices calculated in this study strongly suggested an apparent Cd, Cr and Ni pollution in the studied beach sediments due to natural and anthropogenic contamination. Study findings indicated the HI values were greater ...

Distinct patterns of sedimentary phosphorus fractionation and mobilization in the seafloor of the Black Sea, Marmara Sea and Mediterranean Sea

Akçay, İsmail

Phosphorus (P) is a key element to all life that is used for structural and functional component of all organisms. The cycling of sedimentary P may differ depending on the redox-conditions of the overlying waters affecting the dynamics, and distribution of P-fractions and the elements that are highly coupled to P cycle. Though biogeochemistry of water column in the three interconnected marine basins of Black, Marmara and Mediterranean Seas have been studied extensively, few studies were carried out to understand sedimentary P dynamics in these regions. In this study, therefore, the biogeochemical cycling of sedimentary P and related variables such as porewater nutrients, sedimentary organic carbon, nitrogen and reactive iron were studied in selected sites at the three interconnected marine...

Metal Pollution Status of Surface Sediments in the Two Coastal Regions of the Mersin Bay, Northeastern Mediterranean Sea

Akçay, İsmail | Özbay, Özgür

The objective of this study is to determine metal pollution status of surface sediments in the two coastal regions of Mersin Bay under the influence of Seyhan and Göksu River inflows for the 2005-2009 period. The average metal concentrations orders were found to be Al > Cr > Cu > Zn > Cd for the Station Mersin affected by Seyhan River inflows and Al > Zn > Cr > Cu > Cd for the Station Taşucu under the influence of Göksu River. According to classification of metal pollution of surface sediments, though there was no Cd pollution, the sediments are highly polluted by heavy metals Cr, Cu and Zn in the Seyhan River influenced coastal region due to agricultural and industrial wastewater discharges.

Assessment of trophic status of the northeastern Mediterranean coastal waters: eutrophication classification tools revisited

Akçay, İsmail

The Eastern Mediterranean and its Cilician Basin offshore waters have oligotrophic features with low nutrient concentrations, low primary production, and high water transparency. However, the wide shelf area of the Cilician Basin is subject to contaminated river inflows with enhanced nutrient loads and direct discharges of urban wastewaters of southern Turkey, leading to develop local eutrophic/mesotrophic conditions in the inner sites of Mersin and Iskenderun Bays on the Cilician Basin. For the assessment of changing trophic status of the coastal and the bay water bodies under anthropogenic pressures since the 1980s, five extensive field studies were performed in summer and winter periods of 2014, 2015, and 2016. Physical and eutrophication-related biochemical parameters (salinity, temper...

Eutrophication Status of the Berdan and Göksu River Basins in Turkey

Akçay, İsmail | Özbay, Özgür | Alp, Mehmet Tahir

In this study, the eutrophication status of the Berdan and Göksu River Basins was determined by using recently obtained data between September 2021 and August 2022. Very high total phosphorus and trophic index (TRIX) values indicated that all stations visited in the Berdan, and Göksu River Basins were characterized as eutrophic (bad). The correlations between TRIX and eutrophication-related parameters showed strong and positive relations between TRIX and concentrations of Chlorophyll-a and total phosphorus strongly suggesting that the increase in total phosphorus concentrations highly enhanced primary productivity and eutrophication. The P-enrichment in the Berdan and Göksu River Basins caused eutrophication in these river waters, leading to the further development of coastal eutrophicatio...

Assessment of Ecological and Potential Health Risk Caused by Nitrate Pollution of the Berdan and Göksu River Basins, Turkey

Özbay, Özgür | Akçay, İsmail

To determine ecological and health risk assessment of the Berdan and Göksu river waters, principal physical and biochemical variables were measured monthly between September 2021 and August 2022 in the Berdan and Göksu river basins. Ecological risk assessment of the studied river basins indicated that both the Berdan and Göksu river waters were contaminated by phosphorus. Potential health risk assessment of the Berdan and Göksu river basins showed that the calculated Health Quotient values in the two visited stations in the Berdan river exceeded 0.1 indicating low cancer risk for both adults and children whilst one visited station in the Göksu River basin showed low cancer risk for children. The health risk assessment also indicated that the Health Quotient values calculated for children w...

Distribution of heavy metals in surface sediments of a Coastal Lagoon (Akyatan Lagoon, Northeastern Mediterranean Sea): Ecological and potential health risk assessment

Özbay, Özgür | Akçay, İsmail | Alp, Mehmet Tahir

Coastal lagoons are highly enriched by heavy metals due to various natural and anthropogenic pressures. Sediment heavy metal pollution status and potential health risk assessment of the Akyatan Lagoon were determined from the seasonally obtained sediment samples between January 2022 and October 2022. The heavy metal concentrations in surface sediments of the Akyatan Lagoon ranged between 25.73 and 70.87 g/kg for Al, 10.28–31.03 mg/kg for Co, 0.11–1.42 mg/kg for Cd, 56.22–181.64 mg/kg for Cr, 10.06–34.16 mg/kg for Cu, 13.94–43.39 g/kg for Fe, 361.45–1118.82 mg/kg for Mn, 61.53–209.42 mg/kg for Ni, 9.46–34.43 mg/kg for Pb, and 19.57–117.42 mg/kg for Zn, respectively. The calculated ecological risk indices showed moderate Co, Cd, Cr, Ni, and Pb contamination for surface sediments of the Akyat...

BIOACCUMULATION OF HEAVY METALS IN MACROALGAE ALONG THE MERSIN COAST, NORTHEASTERN MEDITERRANEAN SEA

Akçay, İsmail | Özbay, Özgür

Nutrient inputs from two major rivers into the cilician basin of the north-eastern Mediterranean Sea.

Türkeri, Mehmet | Marankoz, Suat | Özbay, Özgür | Akçay, İsmail | Alp, Mehmet Tahir

In this study, dissolved nutrients concentrations were measured monthly at downstream points of the two regional rivers (the Berdan and Göksu rivers) flowing into the Cilician Basin of the North-eastern (NE) Mediterranean Sea.The dissolved nutrients data obtained between September 2021 and August 2022 were used to determine riverine nutrient fluxes. This study showed that spatial and temporal variations were recorded in nutrients concentrations of the two regional rivers with the maximum values consistently recorded in the Berdan River having lower volume fluxes.The annual nutrient inputs of the two regional rivers indicated that higher amounts of dissolved nutrients were carried by the Göksu River due to its higher volume fluxrate. The calculated molar ratios from total nitrogen (TN)and p...

Assessment of eutrophication in the Berdan River Basin (Türkiye) using various classification tools

Özbay, Özgür | Akçay, İsmail | Alp, Mehmet Tahir

The trophic status of the Berdan River Basin was determined using univariate and multivariate classification tools. The results indicated that the water quality/ trophic status of a downstream section of the Berdan River was characterized as “poor/eutrophic” due to anthropogenic inputs from agricultural, industrial and domestic wastewater discharges. Strong and positive correlations between TRIX values and concentrations of eutrophication parameters suggest that nutrient enrichment of water in the Berdan River during its flow will result in further eutrophication in the coastal region of the NE Mediterranean Sea. Therefore, the trophic and pollution status of the Berdan River, as well as other regional rivers flowing into the coastal area of the NE Mediterranean Sea should be monitored to ...

Heavy Metal Distributions of Macroalgal Species From the Mersin Inner Bay, Türkiye

Özbay, Özgür | Akçay, İsmail

The bio-accumulation of heavy metals in macroalgae poses significant risks to marine ecosystems and human health. In this study, heavy metal distributions of macroalgae and potential health risk assessment in the Mersin inner Bay were determined from macroalgae (Stypopodium schimperi, Padina pavonica, Laurencia obtusa, Dictyota sp., Sargassum vulgare, Jania rubens, Halopithys sp., Osmundea sp., Halopithys incurve, Ulva intestinalis, Entromorpha flexuosa, Ulva linza) samples collected between February and September 2021. The levels of heavy metals were found as 1.24-5.93 g/kg for aluminum, 0.61-5.26 g/kg for iron, 1.17-7.61 mg/kg for cobalt, 0.03-0.21 mg/kg for cadmium, 4.26-43.10 mg/kg for chromium, 0.28-437.52 mg/kg for cupper, 17.90-139.08 mg/kg for manganese, 2.78-79.25 mg/kg for nickel...