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Metal pollution in Al-Khobar seawater, Arabian Gulf, Saudi Arabia Полный текст
2017
Alharbi, Talal | Alfaifi, Hussain | El-Sorogy, Abdelbaset
In order to assess heavy metals pollution along the Al-Khobar coastline, 30 seawater samples and 15 sediment ones were collected for Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Cd, Hg and Pb analysis by Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). The analysis indicated a southward decreasing pattern in most heavy metal concentrations and the average values of Zn, Fe, Mn, Cu, As and Cr were higher than the ones reported from some worldwide seas and gulfs. Most of the highest levels were recorded within the bays and were related with in situ under sediments especially that composed of clays and very fine sands, and in localities characterized with anthropogenic activities like landfilling, desalination plants, fishing boats, oil spills and solid rubbish. The results of the present study provide useful background for further marine investigation and management in the Arabian Gulf region.
Показать больше [+] Меньше [-]Coastal dynamics vs beach users attitudes and perceptions to enhance environmental conservation and management effectiveness Полный текст
2017
Aretano, Roberta | Parlagreco, Luca | Semeraro, Teodoro | Zurlini, Giovanni | Petrosillo, Irene
This work carries out a landscape analysis for the last 60years to compare the degree of preservation of two areas on the same Italian coastline characterized by different environmental protection levels: a National designated protected areas and a highly tourist coastal destination. The conversion of natural land-covers into human land uses were detected for protected and unprotected coastal stretches highlighting that the only establishment of a protected area is not enough to stem undesirable land-use outcomes. A survey analysis was also conducted to assess attitudes of beach users and to evaluate their perception of natural habitats, beach and coastal water quality, and coastal dynamic over time. The results of 2071 questionnaires showed that there is similarity between subjective and objective data. However, several beach users perceived a bad quality of coastal water in the legally unprotected coastal area. The implications from a planning and management perspective are discussed.
Показать больше [+] Меньше [-]Trace elements in Mediterranean seagrasses: Accumulation, tolerance and biomonitoring. A review Полный текст
2017
Bonanno, Giuseppe | Orlando Bonaca, Martina
This study investigated the state of the art on trace elements in Mediterranean seagrasses, and their close environment (seawater and sediment). The analyzed species were Posidonia oceanica, Cymodocea nodosa, Halophila stipulacea, Zostera marina and Zostera noltei. All these species showed high tolerance to pollution and high capacity of accumulation of trace elements. Seagrasses also showed similar patterns of accumulation: the highest concentrations of As, Hg and Pb were found in the roots, whereas those of Cd, Cr, Cu, Mn, Ni and Zn were found in the leaves. Phytotoxic levels in seagrasses are unknown for most trace elements. The accumulation of trace elements in seagrasses is widely recognized as a risk to the whole food web, but the real magnitude of this risk is still uncertain. Seagrasses are known to act as trace element bioindicators, but this potential is still poorly valued for the creation of biomonitoring networks.
Показать больше [+] Меньше [-]Sedimentary records of recent anthropogenic eutrophication and metal contamination in Zhelin Bay, an important mariculture area in Southern China Полный текст
2017
Lu, Xin-Xin | Wang, Zhao-Hui | Feng, Jie
Dinoflagellate cysts (dinocysts), biogenic elements and metals were analyzed from sediment cores collected from Zhelin Bay of the South China Sea in December 2008 to understand the environmental changes over the past 50years. Dinocyst concentrations ranged from 0cysts/g to 770cysts/g, and they were dominated by heterotrophic taxa. There was a clear increase trend upcore for biogenic elements, except for biogenic silica. Metals originated from both the lithogenic source and human activities, and significantly increased after 1985–1995. Environmental changes in the past 50years can be divided into three stages: (1) before 1985, during which biogenic elements, cyst flux and metals were low; (2) from 1985 to the early 2000s, characterized by an obvious increase of dinocysts, TOC, TN and most metals, while TOC/TN and BSi decreased; and (3) after 2000, the period of rapid increase of dinocysts, TOC and TN but decrease of certain contamination metals.
Показать больше [+] Меньше [-]Eutrophication, harmful algae and biodiversity — Challenging paradigms in a world of complex nutrient changes Полный текст
2017
Glibert, Patricia M.
Eutrophication is a complex process and often associated with not only a change in overall algal biomass but also with a change in biodiversity. Common metrics of eutrophication (e.g., chlorophyll a), total nitrogen (TN) and phosphorus (TP) are not adequate for understanding biodiversity changes, especially those associated with harmful algal bloom (HAB) proliferations. Harmful algae can increase disproportionately with eutrophication, depending on which nutrients change and in what proportion. This paper challenges several classic paradigms in our understanding of eutrophication and associated biodiversity changes. The underlying message is that nutrient proportions and forms can alter biodiversity, even when nutrients are at concentrations in excess of those considered limiting. The global HAB problem is on a trajectory for more blooms, more toxins, more often, in more places. Our approach to management of HABs and eutrophication must consider the broader complexity of nutrient effects at scales ranging from physiological to ecological.
Показать больше [+] Меньше [-]Tools for evaluating environmental performance at Brazilian public ports: Analysis and proposal Полный текст
2017
Roos, Erica Caetano | Kliemann Neto, Francisco José
The port sector critically needs improved management techniques to evaluate its environmental performance. In the present study, we conducted an exploratory research to understand the metrics used in the Brazilian public ports to assess their environmental performance. We considered two state agencies and two port authorities of southern Brazil. As preliminary results, we found that economic factors are excluded in the tools for measuring environmental performance. A system of indicators to address this shortcoming was then proposed, but it could not be applied because of data deficiencies. Thus, the system was divided into two parts: a simplified system with 7 indicators (measuring costs related to criteria were measured only technically) and an advanced system with 5 indicators (approaching costs were currently difficult to measure). Thus, the proposed indicators can be applied by port authorities to facilitate decision-making related to environmental management. As suggestions for further work, we propose research that includes more ports, both public and private, to provide an overview at the national level.
Показать больше [+] Меньше [-]Detection of metal induced cytopathological alterations and DNA damage in the gills and hepatopancreas of green mussel Perna viridis from Ennore Estuary, Chennai, India Полный текст
2017
Vasanthi, Lourduraj A. | Revathi, Peranandam | Babu Rajendran, Ramaswamy | Munuswamy, Natesan
This study report the impact of heavy metals on cytopathology and DNA damage in the gills and hepatopancreas of Perna viridis collected from Ennore estuary and the Kovalam coastal waters. Principal Component Analysis (PCA) showed significant differences among all variables at the scale of plots. The ultrastructural alterations such as lack of microvilli, distorted mitochondria, electron dense particles and the presence of large mucous droplets were common in the gill and hepatopancreatic cells of mussels from Ennore estuary. However, the gill and hepatopancreatic cells of P. viridis from Kovalam revealed normal compartmentalization of cells. The percentage of tail DNA in the mussels from Ennore estuary was recorded as 12.44 and 10.14% in the gills and hepatopancreas respectively. Overall, it has been demonstrated that the Comet and cytopathological assays are useful biomarkers to assess the level of pollution and it provide reliable information on ecotoxicology and genotoxicology of coastal waters.
Показать больше [+] Меньше [-]Remote sensing and water quality indicators in the Korean West coast: Spatio-temporal structures of MODIS-derived chlorophyll-a and total suspended solids Полный текст
2017
Kim, Hae-Cheol | Son, Seunghyun | Kim, Yong Hoon | Khim, Jong Seong | Nam, Jungho | Chang, Won Keun | Lee, Jung-Ho | Lee, Chang Hee | Ryu, Jongseong
The Yellow Sea is a shallow marginal sea with a large tidal range. In this study, ten areas located along the western coast of the Korean Peninsula are investigated with respect to remotely sensed water quality indicators derived from NASA MODIS aboard of the satellite Aqua. We found that there was a strong seasonal trend with spatial heterogeneity. In specific, a strong six-month phase-lag was found between chlorophyll-a and total suspended solid owing to their inversed seasonality, which could be explained by different dynamics and environmental settings. Chlorophyll-a concentration seemed to be dominantly influenced by temperature, while total suspended solid was largely governed by local tidal forcing and bottom topography. This study demonstrated the potential and applicability of satellite products in coastal management, and highlighted find that remote-sensing would be a promising tool in resolving orthogonality of large spatio-temporal scale variabilities when combining with proper time series analyses.
Показать больше [+] Меньше [-]Uncertainty quantification and reliability assessment in operational oil spill forecast modeling system Полный текст
2017
Hou, Xianlong | Hodges, Ben R. | Feng, Dongyu | Liu, Qixiao
As oil transport increasing in the Texas bays, greater risks of ship collisions will become a challenge, yielding oil spill accidents as a consequence. To minimize the ecological damage and optimize rapid response, emergency managers need to be informed with how fast and where oil will spread as soon as possible after a spill. The state-of-the-art operational oil spill forecast modeling system improves the oil spill response into a new stage. However uncertainty due to predicted data inputs often elicits compromise on the reliability of the forecast result, leading to misdirection in contingency planning. Thus understanding the forecast uncertainty and reliability become significant. In this paper, Monte Carlo simulation is implemented to provide parameters to generate forecast probability maps. The oil spill forecast uncertainty is thus quantified by comparing the forecast probability map and the associated hindcast simulation. A HyosPy-based simple statistic model is developed to assess the reliability of an oil spill forecast in term of belief degree. The technologies developed in this study create a prototype for uncertainty and reliability analysis in numerical oil spill forecast modeling system, providing emergency managers to improve the capability of real time operational oil spill response and impact assessment.
Показать больше [+] Меньше [-]Cultivation of activated sludge using sea mud as seed to treat industrial phenolic wastewater with high salinity Полный текст
2017
Tan, Songwen | Cui, Chunzhi | Hou, Yang | Chen, Xuncai | Xu, Aiqin | Li, Weiguo | You, Hong
A technique is proposed to treat saline hazardous wastewater by using marine activated sludge, cultivated with sea mud as seed. Since the developed marine activated sludge had phenol-tolerant microorganisms (MAS-1, MAS-2 and MAS-3) which originated from the ocean, it was envisaged that these bacteria could survive and breakdown phenol in saline environments. In this work, typical phenol-tolerant microorganisms were isolated from the marine activated sludge and identified. After a hierarchical acclimation process, the marine activated sludge was used to treat the industrial phenolic wastewater with high salinity. The marine activated sludge was able to break down phenol and other organic components effectively and efficiently in treating the wastewater with salinity of 5.7% w/v. The results showed a high removal of phenol (99%), COD (80%) and NH3-N (68%).
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