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GIS-based health assessment of the marine ecosystem in Laizhou Bay, China
2017
Song, Debin | Gao, Zhiqiang | Zhang, Hua | Xu, Fuxiang | Zheng, Xiangyu | Ai, Jinquan | Hu, Xiaoke | Huang, Guopei | Zhang, Haibo
According to 2014–2016 monitoring data, an assessment index system including water quality, depositional environment and ecosystem was built to evaluate the health statue of marine ecosystem in the Laizhou Bay using analytic hierarchy process (AHP) method. The results, spatialized in ArcGIS software, show: while the comprehensive ecological health index is 0.62, the ecological environmental quality in the Laizhou Bay is in a sub-healthy state; the unhealthy area is mainly concentrated in southwestern inshore region, and impacted by serious environmental problems, such as water eutrophication and heavy metal pollution; the northwestern and southeastern inshore regions are in a sub-healthy state, while the eastern inshore and northern areas are in the healthiest state. The land-based pollutants that discharge into the sea may be the leading factors that are causing ecological environment deterioration in the Laizhou Bay, and the reclamation work ongoing around the port has exacerbated the ecological risk.
Show more [+] Less [-]Significance of beach geomorphology on fecal indicator bacteria levels
2017
Donahue, Allison | Feng, Zhixuan | Kelly, Elizabeth | Reniers, Ad | Solo-Gabriele, Helena M.
Large databases of fecal indicator bacteria (FIB) measurements are available for coastal waters. With the assistance of satellite imagery, we illustrated the power of assessing data for many sites by evaluating beach features such as geomorphology, distance from rivers and canals, presence of piers and causeways, and degree of urbanization coupled with the enterococci FIB database for the state of Florida. We found that beach geomorphology was the primary characteristic associated with enterococci levels that exceeded regulatory guidelines. Beaches in close proximity to marshes or within bays had higher enterococci exceedances in comparison to open coast beaches. For open coast beaches, greater enterococci exceedances were associated with nearby rivers and higher levels of urbanization. Piers and causeways had a minimal contribution, as their effect was often overwhelmed by beach geomorphology. Results can be used to understand the potential causes of elevated enterococci levels and to promote public health.
Show more [+] Less [-]Determination of buildup and dilution of wastewater effluent in shellfish growing waters through a modified application of super-position
2017
Goblick, Gregory N. | Ao, Yaping | Anbarchian, Julie M. | Calci, Kevin R.
Since 1925, dilution analysis has been used to minimize pathogenic impacts to bivalve molluscan shellfish growing areas from treated wastewater effluent in the National Shellfish Sanitation Program (NSSP). For over twenty five years, the U.S. Food and Drug Administration (FDA) has recommended a minimum of 1000:1 dilution of effluent within prohibited closure zones established around wastewater treatment plant (WWTP) discharges. During May 2010, using recent technologies, a hydrographic dye study was conducted in conjunction with a pathogen bioaccumulation study in shellfish adjacent to a WWTP discharge in Yarmouth, ME. For the first time an improved method of the super-position principle was used to determine the buildup of dye tagged sewage effluent and steady state dilution in tidal waters. Results of the improved method of dilution analysis illustrate an economical, reliable and more accurate and manageable approach for estimating the buildup and steady state pollutant conditions in coastal and estuarine waters.
Show more [+] Less [-]Effect of the interaction between transplants of the epiphytic lichen Pseudevernia furfuracea L. (Zopf) and rainfall on the variation of element concentrations associated with the water-soluble part of atmospheric depositions
2017
Gallo, Luana | Corapi, Anna | Apollaro, Carmine | Vespasiano, Giovanni | Lucadamo, Lucio
Water Soluble Bulk Deposition (WSBD) and Water Soluble Leaching (WSL) from Pseudevernia furfuracea thalli transplanted in a anthropized zone were separately collected in four locations where weather stations were set up for monitoring rainfalls rate and daily temperature.The thalli were exposed for three months during which 13 major rainfalls took place. The concentrations of 15 elements (Al, V, Cr, Mn, Co, Ni, Cu, Zn, Mo, Pb, As, Cd, Ti, Sn, Sb) were measured as well in WSBD and WSL as in the lichen thalli at the end of the exposure period. The total bioaccumulation of each element was significantly correlated with its % representation in both the lichen input (WSBD) and output (WSL). Elements with a small water-soluble input-pool were mostly taken up by the thalli (output/input < 1). Among the elements with a high input-pool, Zn was nearly systematically taken up while Al and Mn were lost (output/input > 1). Al showed a significant direct correlation with the increase in mm and hours of rainfall (i.e. transition from net loss to net uptake) while Mn showed an inverse correlation (transition from net uptake to net loss), which may be due to element competition modulated by water-stimulated lichen physiology. Al was strongly bioaccumulated while Mn showed a slight increase in exposed thalli. This suggests that rainfall-induced loss can result in an underestimation by lichen biomonitoring of element concentrations in atmospheric deposition and an increase in the bioavailability of potential toxic elements for other environmental compartments.
Show more [+] Less [-]Assessing human exposure to PM10-bound polycyclic aromatic hydrocarbons during fireworks displays
2017
Pongpiachan, Siwatt | Hattayanone, Mattanawadee | Suttinun, Oramas | Khumsup, Chukkapong | Kittikoon, Itthipon | Hirunyatrakul, Phoosak | Cao, Junji
The “Loy Krathong” festival is a major annual Thai event that includes firework displays. It takes place on the evening of the full moon in the 12th month of the traditional Thai lunar calendar. Since fireworks are widely considered a major source of PAHs, it is considered reasonable to expect a significant increase in PAH levels during this event. The overall PAH profile at the six air quality observatories operated by the Pollution Control Department (PCD), Ministry of Natural Resources and Environment (MNRE), showed that the Kingdom of Thailand's atmosphere was dominated by 5–6-ring PAHs during the firework display period. A significant increase in ΣPAHs (153%) was observed during firework displays. A statistical analysis coupled with the application of diagnostic binary PAH ratios was conducted to determine whether the detected increase in PAH congeners during the festival period was due to firework combustion or whether it was a coincidental effect caused by vehicular exhausts, long-range atmospheric transportation, photolysis and chemical degradation. The average incremental lifetime cancer risk (ILCR) values of adults and children living in Bangkok as estimated by three different TEQs for ingestion, dermal contact, and inhalation exposure pathways were greatly lesser than the US EPA baseline, further highlighting that the cancer risk of bonfire night falls into the ‘‘acceptable level’’ range.
Show more [+] Less [-]Polycyclic aromatic hydrocarbons (PAHs) in sediment and sea urchin (Echinometra mathaei) from the intertidal ecosystem of the northern Persian Gulf: Distribution, sources, and bioavailability
2017
Keshavarzifard, Mehrzad | Moore, Farid | Keshavarzi, Behnam | Sharifi, Reza
The distribution, sources and bioavailability of polycyclic aromatic hydrocarbons (PAHs) in sediment and sea urchin (Echinometra mathaei) from the intertidal zone of the northern Persian Gulf were investigated. Total PAH concentrations varied from 12.8 to 81.25 and from 16.7 to 35 μgKg−1 dry weight in sediment and Echinometra mathaei, respectively. The PAH concentrations can be classified as low. Source identification and apportionment using diagnostic ratios and principal component analysis demonstrate that the combustion of fossil fuels, road traffic, combustion of natural gas and biomass, and oil spill could be considered as the main sources of PAH contamination. The first PAH biota-sediment accumulation factors (BSAF) data from sediment to Echinometra mathaei in the intertidal zone of the northern Persian Gulf were calculated, indicating accumulation of both lower and higher molecular weight PAHs, with a preferential accumulation of lower molecular weight PAHs.
Show more [+] Less [-]Cryptosporidium species from common edible bivalves in Manila Bay, Philippines
2017
Pagoso, Edison Jay A. | Rivera, Windell L.
Manila Bay is one of the major propagation sites of edible bivalves in the Philippines. Studies have shown that bivalves might be contaminated with human pathogens like the protozoan parasite Cryptosporidium, one of the major causes of gastroenteritis in the world. In this study, Cryptosporidium from four species of edible bivalves were isolated using a combination of sucrose flotation and immunomagnetic separation. Using direct fluorescent antibody test, Cryptosporidium oocysts were found in 67 out of 144 samples collected. DNA sequence analysis of the 18S rRNA gene of the isolates detected C. parvum and C. hominis (major causes of human cryptosporidiosis) and C. meleagridis (causes infection in avian species). Analysis of the 60kDa glycoprotein gene further confirmed the genotypes of the Cryptosporidium isolates. This study is the first to provide baseline information on Cryptosporidium contamination of Manila Bay where bivalves are commonly cultured.
Show more [+] Less [-]Biodiversity hotspot for marine invertebrates around the Dokdo, East Sea, Korea: Ecological checklist revisited
2017
Song, Sung Joon | Park, Jinsoon | Ryu, Jongseong | Rho, Hyun Soo | Kim, Wŏn | Khim, Jong Seong
We extensively reviewed the macrozoobenthos around Dokdo, Korea, by analyzing metadata collected over the past 50years. The Dokdo macrozoobenthos was represented by 578 species belonging to 243 families from 12 phyla, where four major phyla (or classes) collectively accounted for 86% to total. Mollusks, arthropods, and cnidarians were semi-equally occurred in intertidal and subtidal areas, while polychetes dominated the subtidal zone. The northern most region of Dokdo had the greatest biodiversity (173 species). The taxonomic distinctness analysis (delta+) indicated a close association between species by region, although the number of species varied greatly. About half of the species did not occur cross the locations (n=20), indicating strong habitat preferences of Dokdo macrofaunal assemblages. Overall, the diversity of Dokdo was greater than that of Ulleung Island (east coast), but comparable to that of the well-developed tidal flats in the western Korean waters, highlighting its status as a biodiversity hotspot.
Show more [+] Less [-]Characteristics and origins of air pollutants and carbonaceous aerosols during wintertime haze episodes at a rural site in the Yangtze River Delta, China
2017
Bao, Mengying | Cao, Fang | Chang, Yunhua | Zhang, Yan-Lin | Gao, Yaqi | Liu, Xiaoyan | Zhang, Yuanyuan | Zhang, Wenqi | Tang, Tianran | Xu, Zufei | Liu, Shoudong | Lee, Xuhui | Li, Jun | Zhang, Gan
China has frequently suffered regional-scale haze pollution in recent years. In this study, real-time observation data such as PM2.5, PM10, SO2, NO2, CO and O3 were used to analyze wintertime haze events at a rural site (Dongshan) in the Yangtze River Delta (YRD). 3-hour resolution organic carbon (OC) and elemental carbon (EC) were also measured to further investigate the sources of PM2.5. The hybrid receptor models were used to identify source regions of PM2.5. The results showed that both regional transport and local emissions significantly contribute to air pollution at Dongshan during haze periods. The source areas affecting high PM2.5 concentrations were mainly located in nearby urbanized provinces (i.e., Jiangsu, Anhui and Zhejiang) and industrial provinces (i.e., Shandong and Hebei) in eastern China. Furthermore, open biomass-burning emissions in south China (i.e., Jiangxi, Hunan, Guangdong and Fujian) decreased regional air quality, which was supported by MODIS fire spots and receptor models. During clean periods, air masses were originated from remote regions such as Mongolia and oceanic areas (i.e., the Yellow Sea and the East Sea). Enhanced secondary organic carbon (SOC) formation was found under long-range transport when OC aging was favorable. Contrarily, relatively low SOC formation was found when the site was dominated by local emissions. In addition to local emissions, high PM2.5 concentrations at Dongshan were apparently affected by either regional or long-range transport, which were characterized by relatively low and high wind speeds, respectively. It is necessary to implement the emission control strategies for the industrial and urbanized areas.
Show more [+] Less [-]Degradation dynamics and bioavailability of land-based dissolved organic nitrogen in the Bohai Sea: Linking experiment with modeling
2017
Li, Keqiang | Ma, Yunpeng | Dai, Aiquan | Wang, Xiulin
Dissolved organic nitrogen (DON) is the major nitrogen form in the Bohai Sea. Land-based DON is released into the nitrogen pool and degraded by planktonic microbiota in coastal ocean. In this study, we evaluated the degradation of land-based DON, particularly its dynamics and bioavailability, in coastal water by linking experiment and modeling. Results showed that the degradation rate constant of DON from sewage treatment plant was significantly faster than those of other land-based sources (P<0.05). DON was classified into three categories based on dynamics and bioavailability. The supply of dissolved inorganic nitrogen (DIN) pool from the DON pool of Liao River, Hai River, and Yellow River was explored using a 3D hydrodynamic multi-DON biogeochemical model in the Bohai Sea. In the model, large amounts of DIN were supplied from DON of Liao River than the other rivers because of prolonged flushing time in Liaodong Bay.
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