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Seasonal hypoxia regulates macrobenthic function and structure in the Mississippi Bight Full text
2016
Rakocinski, Chet F. | Menke, Daneen P.
Hypoxic conditions are escalating to the east of the Mississippi River within the Mississippi Bight. The objective of this study was to examine changes in macrobenthic function and structure relative to seasonal hypoxia over a 3.5year period at the 10m (Site 6) and 20m (Site 8) isobaths within the Mississippi Bight. Seasonal hypoxia acted as a regular periodic disturbance during the study period, although the magnitude and duration of hypoxia varied inter-annually. Macrobenthic metrics revealed seasonal hypoxia effects on secondary production potential and community maturity, which agrees with previous studies. In addition, metrics were notably higher at the 20m isobath during the latter half of the study period, following the Deepwater Horizon (DwH) oil spill. This study confirms hypoxia as a major driver affecting the function and structure of soft-bottom macrobenthos in the Mississippi Bight.
Show more [+] Less [-]Pathways of priority pesticides in sediments of coastal lagoons: The case study of Óbidos Lagoon, Portugal Full text
2016
Pinto, M.I. | Vale, C. | Sontag, G. | Noronha, J.P.
This study reports the concentrations of the priority pesticides (PPs) in 14 surface sediments and 21 layers of a sediment core from Óbidos Lagoon, a shallow Portuguese coastal lagoon. Results show that the PPs are confined to the upper part of the lagoon that receives most of the inputs from surface runoff of the surrounding agricultural fields and from small tributaries. Past and recent applied PPs were registered in sediments, aluminum normalized concentrations varying between 0.05×10−7 and 6.85×10−7. The PP risk assessment based on sediment quality guidelines like the “Probable Effect Level” (PEL) shows no biological effects in either sediments or aquatic organisms of Óbidos Lagoon, except for dieldrin, lindane, DDT, heptachlor epoxide and its parent compound heptachlor.
Show more [+] Less [-]PCBs and OCPs in fish along coastal fisheries in China: Distribution and health risk assessment Full text
2016
Pan, Hui | Geng, Jingjing | Qin, Yukun | Tou, Feiyun | Zhou, Junliang | Liu, Min | Yang, Yi
PCBs and OCPs were analyzed in fish (bass) taken along Chinese coastal fisheries. In the bass muscle, PCB, DDT and HCH concentrations were in the range of 1.02–2.2ng/g, 0.44–1.74 and 2.84–106.11ng/gww, respectively. Spatial distribution showed that the concentrations of target contaminants in bass from south fisheries were in general much lower than those from north fisheries in China. The ratios of OCP congeners suggested that technical DDT was not the main input and a recent usage of lindane or old technical HCH residuals could be the source of HCHs. The OCC concentrations in liver (127–442.43ng/gww) from selected samples were 8–12 and 10–14 times higher than those in gills and muscles, respectively. Based on the maximum allowable fish assumption rate (CRlim and CRmm), it could cause human health risk, by consuming bass samples taken from highly contaminated fisheries including QD and ST.
Show more [+] Less [-]Trace metal contamination in surface sediments of intertidal zone from Qinhuangdao, China, revealed by geochemical and magnetic approaches: Distribution, sources, and health risk assessment Full text
2016
Zhu, Zongmin | Xue, Junhui | Deng, Yuzhen | Chen, Lin | Liu, Jiangfeng
Based on geochemical and magnetic approaches, the distribution, sources, and health risk of trace metals in surface sediments from a seashore tourist city were investigated. A significant correlation was found between magnetic susceptibility (χ) and trace metals, which suggested that levels of trace metals in the sediments can be effectively depicted by the magnetic approach. The spatial distribution of χ and trace metals matched well with the city layout with relatively higher values being found in the port and busy tourist areas. This result, together with enrichment factors (EFs) and Tomlinson pollution load index (PLI) of metals, suggested that the influence of human activities on the coastal environment was noticeable. Principal component analysis (PCA) indicated that trace metals in the sediments were derived from both anthropogenic and natural sources. Noncarcinogenic risk assessment showed that there was no potential health risk of exposure to metals by means of ingestion or inhalation.
Show more [+] Less [-]Heavy metal pollution and Pb isotopic tracing in the intertidal surface sediments of Quanzhou Bay, southeast coast of China Full text
2016
Yu, Ruilian | Zhang, Weifang | Hu, Gongren | Lin, Chengqi | Yang, Qiuli
Concentrations of 16 heavy metals and Pb isotopic ratios in the intertidal surface sediments of Quanzhou Bay were determined to study the pollution level of heavy metals and the sources of Pb. The results showed that most concentrations of Cd, Sn, Mn, Cu, Zn, Cr, Pb, Hg, Ni, Co, Cs, Fe and V were higher than the background values, while most concentrations of Ti, Sb and Sr were lower than the background values. The mean concentrations of Cu, Zn, Pb, Cr and Cd exceeded the first-grade criteria of Chinese marine sediment quality. The geo-accumulation indexes revealed that the sediments had been polluted by some heavy metals. The results of Pb isotopic tracing indicated that the total Pb in the sediments were mainly from parent material, industrial emission and vehicle exhaust with the mean contributions of 38.2%, 51.3% and 10.5%, respectively, calculated by a three-end-member model of Pb isotopic ratios.
Show more [+] Less [-]Ophthalmic effects of petroleum dispersant exposure on common murres (Uria aalge): An experimental study Full text
2016
Fiorello, Christine V. | Freeman, Kate | Elias, Becky A. | Whitmer, Emily | Ziccardi, Michael H.
The safety of chemical dispersants used during oil spill responses is largely unknown in birds. We captured common murres in Monterey Bay, CA and exposed them to Corexit EC9500a, crude oil, or a combination in artificial seawater. We performed ophthalmic examinations and measured intraocular pressures and tear production before and after exposure. Loglinear analysis found that exposure to oil or dispersant was related to the development of conjunctivitis and corneal ulcers. Odds ratios for birds exposed to oil or dispersant were positive and significant for the development of conjunctivitis, while odds ratios for the development of corneal ulcers were positive and significant only for birds exposed to a high concentration of oil. Ocular exposure to dispersants and petroleum in seabirds may cause conjunctivitis and may play a role in the development of corneal ulcers. These results have implications for policymakers who develop protocols for the use of dispersants during marine oil spills.
Show more [+] Less [-]Kinetic analysis of simultaneous denitrification and biomineralization of novel Acinetobacter sp. CN86 Full text
2016
Su, Jun-feng | Shi, Jing-xin | Huang, Ting-lin | Ma, Fang
A novel aerobic denitrification and biomineralization strain CN86 was isolated from the Qu Jiang artificial lake. Based on phylogenetic characteristics, the isolated strain was identified as Acinetobacter species. Strain CN86 was confirmed to have the ability to perform simultaneous denitrification and biomineralization. Exponential decay equation was used for the matching of kinetic processes on denitrification and biomineralization. A highest nitrate removal rate was achieved at the pH7.0, organic concentration of 1.5g/L and temperature of 30°C. An optimal hardness removal rate was obtained at the pH9.0, organic concentration of 2.0g/L and temperature of 30°C. Strain CN86 is a suitable candidate for the simultaneous removal of nitrate and hardness in groundwater treatment.
Show more [+] Less [-]Chemical composition of floating and sunken in-situ burn residues from the Deepwater Horizon oil spill Full text
2016
Stout, Scott A. | Payne, James R.
In-situ burning during the Deepwater Horizon oil spill generated tens of thousands of barrels of in-situ burn (ISB) residues in the northern Gulf of Mexico (GoM), most or all of which eventually sank to the seafloor. Chemical analyses showed that floating and sunken (~1400m deep) ISB residues (1) exhibited distinct n-alkanes and UCM profiles inconsistent with vapor-pressure driven evaporation, (2) were relatively enriched in pyrogenic PAHs, particularly less stable (mostly) linear PAH isomers formed during burning, and (3) had lost petroleum biomarkers, relative to their volatility. PAH concentrations in ISB residues indicate that between 26,800 and 37,800kg of total PAHs (TPAH51) and 2880 and 4060kg of 16 Priority Pollutant PAHs were potentially deposited on the seafloor in discrete ISB residue particles. Despite this additional benthic impact, ISB reduced the total mass loadings of PAH from the burned oil to the GoM by 89% (ignoring any re-deposition from atmospheric emissions).
Show more [+] Less [-]The influence of wastewater discharge on water quality in Hawai'i: A comparative study for Lahaina and Kihei, Maui Full text
2016
Miller-Pierce, Mailea R. | Rhoads, Neil A.
In Maui, Hawai'i, wastewater reclamation facilities (WWRFs) dispose of partially treated effluent into injection wells connected to the nearshore environment. Hawai'i State Department of Health data from 2004–2015 were assessed for qualitative trends in nutrient, turbidity, and Chlorophyll a water quality (WQ) impairments for fourteen marine sites on Maui Island. We introduce a novel method, the Qualitative Impact Percentage (QIP), to facilitate a qualitative comparison of disparate factors contributing to WQ impairment. Sites near the Lahaina WWRF in West Maui, which was found in violation of the Clean Water Act in 2014, had fewer exceedances and lower geometric means compared to sites near the Kihei WWRF. Our results suggest that WQ impairments may be a greater concern in Kihei than previously acknowledged. This paper attempts to raise the awareness of policymakers and the public and to encourage further research assessing the effects of the Kihei WWRF on the marine environment.
Show more [+] Less [-]Heavy metals in river and coast sediments of the Jakarta Bay region (Indonesia) — Geogenic versus anthropogenic sources Full text
2016
Sindern, Sven | Tremöhlen, Martin | Dsikowitzky, Larissa | Gronen, Lars | Schwarzbauer, Jan | Siregar, Tuti Hartati | Ariyani, Farida | Irianto, Hari Eko
Sediment geochemistry of the Jakarta region, a densely populated tropical coast, is studied — with particular focus on rivers discharging to Jakarta Bay. Weathering volcanics in the river catchment area control the composition of major elements, As, Cr and in part Cu. In contrast, Zn, Ni, Pb and partly Cu are affected by anthropogenic sources, mainly in central Jakarta City. The data reflect a high variability of local emission sources, among which metal processing industries, fertilizers or untreated animal waste may be important. In particular, the role of street dusts is emphasized. Locally, heavy metals reach levels considered to have adverse biological effects. River discharge leads to anthropogenic enrichment of heavy metals in the coastal sediments. Element data also show geogenic effects on the composition of the coastal sediments, such as mixing of detrital silicates with biogenic carbonates as well as suspended particulate matter from the ocean.
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