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Informing Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada) Texte intégral
2015
Filgueira, Ramón | Guyondet, T. | Bacher, Cédric | Comeau, Luc A.
Informing Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada) Texte intégral
2015
Filgueira, Ramón | Guyondet, T. | Bacher, Cédric | Comeau, Luc A.
A moratorium on further bivalve leasing was established in 1999–2000 in Prince Edward Island (Canada). Recently, a marine spatial planning process was initiated explore potential mussel culture expansion in Malpeque Bay. This study focuses on the effects of a projected expansion scenario on productivity of existing leases and available suspended food resources. The aim is to provide a robust scientific assessment using available datasets and three modelling approaches ranging in complexity: (1) a connectivity analysis among culture areas; (2) a scenario analysis of organic seston dynamics based on a simplified biogeochemical model; and (3) a scenario analysis of phytoplankton dynamics based on an ecosystem model. These complementary approaches suggest (1) new leases can affect existing culture both through direct connectivity and through bay-scale effects driven by the overall increase in mussel biomass, and (2) a net reduction of phytoplankton within the bounds of its natural variation in the area.
Afficher plus [+] Moins [-]Informing Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada) Texte intégral
2015
Filgueira, Ramon | Guyondet, Thomas | Bacher, Cedric | Comeau, Luc A.
A moratorium on further bivalve leasing was established in 1999–2000 in Prince Edward Island (Canada). Recently, a marine spatial planning process was initiated explore potential mussel culture expansion in Malpeque Bay. This study focuses on the effects of a projected expansion scenario on productivity of existing leases and available suspended food resources. The aim is to provide a robust scientific assessment using available datasets and three modelling approaches ranging in complexity: (1) a connectivity analysis among culture areas; (2) a scenario analysis of organic seston dynamics based on a simplified biogeochemical model; and (3) a scenario analysis of phytoplankton dynamics based on an ecosystem model. These complementary approaches suggest (1) new leases can affect existing culture both through direct connectivity and through bay-scale effects driven by the overall increase in mussel biomass, and (2) a net reduction of phytoplankton within the bounds of its natural variation in the area.
Afficher plus [+] Moins [-]Characterization of spatial and temporal variability in hydrochemistry of Johor Straits, Malaysia Texte intégral
2015
Abdullah, Pauzi | Sharifah Mastura, | Jaafar, Othman | Mastura Mahmud, | Khalik, Wan Mohd Afiq Wan Mohd
Characterization of hydrochemistry changes in Johor Straits within 5years of monitoring works was successfully carried out. Water quality data sets (27 stations and 19 parameters) collected in this area were interpreted subject to multivariate statistical analysis. Cluster analysis grouped all the stations into four clusters ((Dlink/Dmax)×100<90) and two clusters ((Dlink/Dmax)×100<80) for site and period similarities. Principal component analysis rendered six significant components (eigenvalue>1) that explained 82.6% of the total variance of the data set. Classification matrix of discriminant analysis assigned 88.9–92.6% and 83.3–100% correctness in spatial and temporal variability, respectively. Times series analysis then confirmed that only four parameters were not significant over time change. Therefore, it is imperative that the environmental impact of reclamation and dredging works, municipal or industrial discharge, marine aquaculture and shipping activities in this area be effectively controlled and managed.
Afficher plus [+] Moins [-]Bio-indicator bacteria & environmental variables of the coastal zones: The example of the Güllük Bay, Aegean Sea, Turkey Texte intégral
2015
Kalkan, Samet | Altuğ, Gülşen
In this study bio-indicator bacteria and environmental variable parameters were investigated in the coastal areas of the Güllük Bay, Aegean Sea, Turkey. The seawater samples which were taken from surface (0–30cm) were tested regarding total and fecal coliform, streptococci and nutrients from May to February in 2012–2013. The primary hydrographic parameters were recorded using multiparameter (YSI 556) in situ at the sampling stations. The highest fecal pollution stress and indicator bacteria values were observed in the period between June and August. The finding showed that bacterial pollution sources of the study area, especially in the summer season, under the control of increasing anthropogenic activities. The finding showed that terrestrial pollution sources carry a potential risk for public and ecosystem health and the sustainable use of living sources. Precautions should be formulated and put into action immediately in order to protect the region from bacteriological risks.
Afficher plus [+] Moins [-]Distribution, enrichment and sources of thallium in the surface sediments of the southwestern coastal Laizhou Bay, Bohai Sea Texte intégral
2015
Zhuang, Wen | Gao, Xuelu
The concentrations of thallium (Tl) in the surface sediments of the southwestern coastal Laizhou Bay and the rivers it connects were determined. In riverine sediments, the Tl concentrations ranged from 0.34 to 0.76μgg−1 in summer; in autumn, the corresponding data were 0.35–1.08μgg−1. In marine sediments, the Tl concentrations ranged from 0.36 to 0.58μgg−1 in summer; and from 0.30 to 0.56μgg−1 in autumn. The grain size, Al and Fe oxides were major factors affecting Tl distribution. Tl in the surface sediments of the studied area was mainly from the natural input with the non-natural input as a subsidiary source. The low concentrations of Tl made it hard to cause potential negative environmental effects in this area.
Afficher plus [+] Moins [-]Biodegradation of phthalate acid esters by different marine microalgal species Texte intégral
2015
Gao, Jing | Chi, Jie
Biodegradation of diethyl phthalate (DEP) and di-n-butyl phthalate (DBP) by three marine algae was investigated. When they were coexistent, DBP was degraded more quickly than DEP. The first-order biodegradation rate constants of DBP in the algal solutions were in the order of Cylindrotheca closterium (0.0169h−1)>Dunaliella salina (0.0035h−1) and Chaetoceros muelleri (0.0034h−1). When singly existed, DEP was degraded more quickly than in a mixture with DBP, indicating that DBP had inhibitory effect on the biodegradation of DEP. Moreover, the degradation trends of DEP and DBP in both extra- and intracellular crude extracts were similar to those in algal solutions. At the end, DEP was largely in water phase, whereas DBP remained in both water phase and algal phase. It can be concluded that biodegradation of DEP was mainly by algal extracellular enzymes, and both extra- and intracellular enzymes played key roles in the degradation of DBP.
Afficher plus [+] Moins [-]The management in response to marine oil spill from ships in China: A systematic review Texte intégral
2015
Xiong, Shangao | Long, Hualou | Tang, Guoping | Wan, Jun | Li, Hongyuan
Historical trends about marine ship-source oil spill incidents from 1990 to 2010 in China were analyzed, and it provided an overview of the status quo of China’s management in response to marine oil spill from ships. The Chinese government has issued a series of laws on marine environmental protection since 1982, and promulgated many regulations to prevent and tackle ship-source oil spill. At present, the oil spill emergency response system established in China has five levels: the national level, sea level, provincial level, port level, and ship level. China has demonstrated its ability to control and remove small-scale oil spill from ships in port area and near-shore coastal waters, and also paid attention to related research and development projects. Although China has made significant progress in managing shipping oil spill, challenges still exist, including strengthening oil spill emergency cooperation, enhancing China’s response capability, and improving relevant research and development projects.
Afficher plus [+] Moins [-]Antifouling assessments on biogenic nanoparticles: A field study from polluted offshore platform Texte intégral
2015
Krishnan, Muthukumar | Sivanandham, Vignesh | Hans-Uwe, Dahms | Murugaiah, Santhosh Gokul | Seeni, Palanichamy | Gopalan, Subramanian | Rathinam, Arthur James
Turbinaria ornata mediated silver nanoparticles (TOAg-NPs) were evaluated for antibacterial activity against 15 biofilm forming bacterial isolates. A field study in natural seawater for 60days showed antifouling activity of TOAg-NPs on stainless steel coupons (SS-304) coated with Apcomin zinc chrome (AZC) primer. Though TOAg-NPs showed broad spectrum of antibacterial activity, the maximum zone of inhibition was with Escherichia coli (71.9%) and a minimum with Micrococcus sp. (40%) due to the EPS secretion from Gram-positive bacteria. Compared to control coupons (18.9 [×103], 67.0 [×103], 13.5 [×104] and 24.7 [×104]CFU/cm2), experimental biocide coupons (71.0 [×102], 32.0 [×103], 82.0 [×103] and 11.3 [×104]CFU/cm2) displayed lesser bacterial population density. Toxicity studies revealed 100% mortality for Balanus amphitrite larvae at 250μgml−1 concentration within 24h, while 56.6% recorded for Artemia marina at the same concentration indicating less toxicity to non target species. It proved that AZC+TOAg-NPs prevent biofouling by its Ag-NS affinity and antimicrobial effectivity.
Afficher plus [+] Moins [-]Spatial pattern and weight of seabed marine litter in the northern and central Adriatic Sea Texte intégral
2015
Strafella, P. | Fabi, G. | Spagnolo, A. | Grati, F. | Polidori, P. | Punzo, E. | Fortibuoni, T. | Marceta, B. | Raicevich, S. | Cvitkovic, I. | Despalatovic, M. | Scarcella, G.
The present study analyzes spatial distribution and typology of marine litter on the seabed in the FAO Geographical Sub-Area 17 (northern and central Adriatic Sea). Two surveys were conducted during fall 2011 and 2012 and 67 stations were sampled each year. Litter items were collected using the “rapido” trawl, a modified beam trawl commonly used by the Italian fishermen to catch flat fish and other benthic species. Marine litter in the catches was sorted and classified in 6 major categories (plastic, metal, glass, rubber, wood, other). Plastic litter was further subdivided in 3 sub-categories based on its source: fishing nets, aquaculture nets and other. Plastic was dominant in terms of weight followed by metal and other categories. The highest concentration of litter was found close to the coast likely as a consequence of high coastal urbanization, river inflow and extensive navigation associated with the morphological and hydrological features of the basin.
Afficher plus [+] Moins [-]A macroalgal germling bioassay to assess biocide concentrations in marine waters Texte intégral
2015
Girling, J.A. | Thomas, K.V. | Brooks, S.J. | Smith, D.J. | Shahsavari, E. | Ball, A.S.
A bioassay method using the early life stages (germlings) of macroalgae was developed to detect toxicity of anti-fouling paint biocides. A laboratory based bioassay using Ulva intestinalis and Fucus spiralis germlings was performed with 4 common anti-fouling biocides (tributyltin (TBT), Irgarol 1051, Diuron and zinc sulphate), over a range of environmentally relevant concentrations (0.0033–10μgl−1). Comparison between the two species showed that germlings of U. intestinalis were better adapted for in-situ monitoring, as germlings of F. spiralis appeared to be too robust to display sufficient growth differences. The response of U. intestinalis germling growth appeared to reflect environmental biocide concentrations. Overall the developed method showed potential for the assessment of the sub-lethal effects of anti-fouling biocides on the early developmental stages of U. intestinalis.
Afficher plus [+] Moins [-]Cumulative pressures and low protection: a concerning blend for Mediterranean MPAs Texte intégral
2015
Rodríguez-Rodríguez, D. | Sánchez-Espinosa, A. | Schröder, C. | Abdul Malak, D. | Rodríguez, J.
This study classifies Mediterranean marine protected areas (MPAs) according to the combined result of pressure level and protection. Six major marine environment pressures were considered: pressures from fish farms, fishing, marine litter, pressures from marinas, pollution from maritime transport, and climate change. MPA protection was assessed through legal protection and management effort. Most MPA area in the Mediterranean is under relatively high pressure level and afforded low protection. Inshore areas show higher pressure levels. Five marine ecoregions, nine countries and nineteen MPA designation categories have over 50% of their MPA area under major concern. The mean number of cumulative pressures occurring in priority MPAs ranges between three and four, although the mean combined intensity of those pressures is low. However, these figures are most likely underestimated, especially for the southern Mediterranean. The most concerning pressures to MPAs regarding extent and intensity were: climate change, fishing and pollution from maritime transport.
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