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Non-indigenous macrozoobenthic species on hard substrata of selected harbours in the Adriatic Sea Full text
2019
Spagnolo, A. | Auriemma, R. | Bacci, T. | Balković, I. | Bertasi, F. | Bolognini, L. | Cabrini, M. | Cilenti, L. | Cuicchi, C. | Cvitković, I. | Despalatović, M. | Grati, F. | Grossi, L. | Jaklin, A. | Lipej, L. | Marković, O. | Mavrič, B. | Mikac, B. | Nasi, F. | Nerlović, V. | Pelosi, S. | Penna, M. | Petović, S. | Punzo, E. | Santucci, A. | Scirocco, T. | Strafella, P. | Trabucco, B. | Travizi, A. | Žuljević, A.
The intense shipping traffic characterising the Adriatic Sea favours the spread of marine organisms. Yet, a study of 12 Adriatic ports (4 on the western side and 8 on the eastern side of the basin) found that non-indigenous species (NIS) accounted for only 4% of the benthic communities settled on hard substrates. The cirripeds Amphibalanus amphitrite and Balanus trigonus, found in 8 harbours, were the most common invaders followed by Amphibalanus eburneus, the ascidian Styela plicata, and the bivalve Magallana gigas. The highest percentage of NIS was recorded in Venice and Ploče, the harbours with the least rich native communities; the lowest percentage was retrieved in Trieste, Koper, Pula, and Rijeka, the harbours hosting the highest species diversity. In contrast, the ports of Bari and Ancona showed both high NIS percentages and highly diversified communities.
Show more [+] Less [-]Emerging and traditional organic markers: Baseline study showing the influence of untraditional anthropogenic activities on coastal zones with multiple activities (Ceará coast, Northeast Brazil) Full text
2019
Molecular markers are useful tools to characterize natural and anthropogenic impacts on coastal zones. Distribution of n-alkanes showed that the Pacoti River was predominantly influenced by terrigenous input. Distribution of polycyclic aromatic hydrocarbon (PAH) indices showed a mix of natural sources, especially pyrogenic influences. Sterol and hormone levels showed sewage discharge. Integrated geographic assessment showed that pyrogenic process and sewage discharge are predominant along the river because of natural and different anthropogenic activities. The upstream region is influenced by rural activities such as livestock and discharge from the sewage treatment plant, whereas the estuarine region is influenced by urban and industrial activities, predominantly the discharge of treated or untreated sewage, vehicle traffic, and manufacture of red ceramics. On the other hand, on the river mouth, there is the predominance of aquaculture activities. Traditional anthropogenic markers are not sufficient for producing a comprehensive assessment of anthropogenic impacts in areas with multiple activities.
Show more [+] Less [-]Microfibers generated from the laundering of cotton, rayon and polyester based fabrics and their aquatic biodegradation Full text
2019
Zambrano, Marielis C. | Pawlak, Joel J. | Daystar, Jesse | Ankeny, Mary | Cheng, Jay J. | Venditti, Richard A.
The effect of fiber type (cotton, polyester, and rayon), temperature, and use of detergent on the number of microfibers released during laundering of knitted fabrics were studied during accelerated laboratory washing (Launder-Ometer) and home laundering experiments. Polyester and cellulose-based fabrics all shed significant amounts of microfibers and shedding levels were increased with higher water temperature and detergent use. Cellulose-based fabrics released more microfibers (0.2–4 mg/g fabric) during accelerated laundering than polyester (0.1–1 mg/g fabric). Using well-controlled aquatic biodegradation experiments it was shown that cotton and rayon microfibers are expected to degrade in natural aquatic aerobic environments whereas polyester microfibers are expected to persist in the environment for long periods of time.
Show more [+] Less [-]Piece-by-piece analysis of additives and manufacturing byproducts in plastics ingested by seabirds: Implication for risk of exposure to seabirds Full text
2019
Tanaka, Kosuke | van Franeker, Jan A. | Deguchi, Tomohiro | Takada, Hideshige
The risk of marine organisms ingesting plastics has become a growing concern due to hazard chemicals in plastics. To identify compounds to which seabirds potentially have substantial exposure, 194 plastics fragments and pellets ingested by seabirds, i.e., northern fulmars from the Faroe Islands, and laysan albatross and black-footed albatross from Mukojima Island, were analyzed piece by piece. Four kinds of UV stabilizers, 2 brominated flame retardants, and styrene oligomers were detected at detection frequencies of 4.6%, 2.1%, and 2.1%, respectively. Concentrations ranging from not detected (n.d.) – 1700 μg/g were measured for UV stabilizers, n.d. – 1100 μg/g for flame retardants, and n.d. – 3200 μg/g for styrene oligomers. We found that these chemicals could be retained in plastics during drifting and fragmentation in the ocean and transported to seabirds. This type of transport via plastics can be direct pathway that introduces hazardous compounds to marine organisms.
Show more [+] Less [-]Remote sensing estimation of the biomass of floating Ulva prolifera and analysis of the main factors driving the interannual variability of the biomass in the Yellow Sea Full text
2019
Xiao, Yanfang | Zhang, Jie | Cui, Tingwei | Gong, Jialong | Liu, Rongjie | Chen, Xiaoying | Liang, Xijian
Since 2007, green tide blooms with Ulva prolifera as the dominant species have occurred every summer in the Yellow Sea. Biomass is a critical parameter used to describe the severity of green tide blooms. In this study, we analyzed the relationships between several indices (normalized difference vegetation index (NDVI), floating algae index (FAI), ratio vegetation index (RVI), enhanced vegetation index (EVI), ocean surface algal bloom index (OSABI), Korea Ocean Satellite Center (KOSC) approach) and the biomass per unit area of Ulva prolifera by using the in situ measurements from a water tank experiment. EVI, NDVI, and FAI showed strong exponential relationships with Ulva prolifera biomass per unit area. In order to apply the relationships to satellite remote sensing data, the impacts of the atmosphere (different aerosol optical depth at 550 nm) and mixed pixels to the relationships were analyzed. The results show that atmosphere has little effect on the relationship between EVI and Ulva prolifera biomass per unit area with R2 = 0.94 and APD (the average percentage deviation) = 19.55% when EVI is calculated from Rrc (Rayleigh-corrected reflectance), and R2 = 0.95 and APD = 17.53% when EVI is calculated from Rtoa (top-of-atmosphere reflectance). Due to the low sensitivity to the atmosphere, the EVI relationship can be directly utilized in the top-of-atmosphere (TOA) reflectance without atmospheric correction. In addition, the EVI was slightly affected by mixed pixels with the APD only increased by ~10%. The EVI relationship was then applied to a long MODIS image time series to obtain the maximal total biomass of floating Ulva prolifera in the Yellow Sea from 2007 to 2016. The results showed that the maximum and minimum total biomass occurred in 2016 (~1.17 million tons) and 2012 (~0.074 million tons), respectively. The main factors that caused the inter-annual biomass variability were analyzed. The total amount of nutrients from Sheyang River which was the largest river on the northern coast of Jiangsu Province, and Porphyra cultivation in the Radial Sand Ridges of Jiangsu Province had both strong correlation with Ulva prolifera total biomass.
Show more [+] Less [-]Spatiotemporal characterization of metals in small craft harbour sediments in Nova Scotia, Canada Full text
2019
Zhang, Hongling | Walker, Tony R. | Davis, Emily | Ma, Guofeng
Spatiotemporal (2001–2017) characterization of sediment metal concentrations were assessed in 31 small craft harbours (SCHs) in Nova Scotia, Canada by analyzing secondary data from government sediment assessment reports. Surficial sediment samples (n = 576) were collected prior to routine maintenance or constriction dredging activities. Sediment metal concentration ranges were 0.5–62 (As), 0.05–3.8 (Cd), 1–305 (Cr), 0.5–220 (Cu), 0.003–1.85 (Hg), 0.73–583 (Pb) and 5–2300 (Zn) mg/kg (dw), respectively. Most sediment metal concentrations (>56% of samples) were below low effect level and >96% were below high effect level sediment quality guidelines, suggesting limited ecological impairment to marine biota. Despite wide temporal coverage (16 years), large variation in sediment concentrations across SCHs were likely due to regular dredging activities preventing long-term accumulation of contaminants. Spatial distribution and enrichment factor results revealed that Canso was most impacted by metals, followed by Clarks Harbour.
Show more [+] Less [-]Beach litter in Ecuador and the Galapagos islands: A baseline to enhance environmental conservation and sustainable beach tourism Full text
2019
Mestanza, Carlos | Botero, Camilo M. | Anfuso, Giorgio | Chica-Ruiz, J Adolfo | Pranzini, Enzo | Mooser, Alexis
The presence and characterization of beach litter was investigated, according to the EA/NALG (2000) methodology, at 59 sites along four provinces of Ecuador, i.e., three continental and the Galapagos Islands Province. The methodology, which has been verified in several countries, was used to classify beaches into four grades (from “A” – excellent to “D” – poor) according to the content of nine types of litter. Twenty-two sites (i.e., 37% of total) obtained Grade “C”, 18 (31%) Grade “B”, 12 (20%) Grade “A”, and 7 (12%) Grade “D”. The province that showed excellent litter grades was the Galapagos Islands where 88% of beaches obtained Grade “A”, whereas Santa Elena and Esmeraldas provinces presented the worst beaches in terms of litter content and abundance. Environmental authorities should focus more attention on continental beaches by improving adequate cleaning operations to make them more attractive to national and international tourism.
Show more [+] Less [-]Mercury and selenium in the filter–feeding whale shark (Rhincodon typus) from two areas of the Gulf of California, Mexico Full text
2019
Pancaldi, Francesca | Galván-Magaña, Felipe | González-Armas, Rogelio | Soto-Jimenez, Martin F. | Whitehead, Darren A. | O'Hara, Todd | Marmolejo-Rodríguez, Ana J. | Vázquez-Haikin, Abraham | Páez Osuna, Federico
Mercury and selenium were measured for first time in the endangered species whale shark (Rhyncodon typus) from two areas of the Gulf of California, Bahía Los Angeles (BLA) and Bahía La Paz (LAP) using dermal biopsies of seventy specimens. Additionally, nineteen zooplankton samples from LAP were analysed. Concentrations (ng/g, wet weight (ww)) in biopsies of BLA ranged from 1 to 40 for Hg and 100 to 680 for Se; while in LAP varied from 1 to 9 for Hg and 11 to 850 for Se. A positive correlation was found for Hg in BLA males biopsies with length. Hg and Se concentrations in the zooplankton from LAP were 1.6 ± 1.8 and 770 ± 930 ng/g, respectively. Hg biomagnification factor ranged from 0.8 to 5.3 in sharks. A molar excess of Se over Hg was found in the biopsies and the zooplankton.
Show more [+] Less [-]Spatio-temporal monitoring of coastal floating marine debris in the Balearic Islands from sea-cleaning boats Full text
2019
Compa, Montserrat | March, David | Deudero, Salud
Spatio-temporal monitoring of coastal floating marine debris in the Balearic Islands from sea-cleaning boats Full text
2019
Compa, Montserrat | March, David | Deudero, Salud
Mismanaged waste is accumulating at an alarming rate in the marine environment. Its presence has caused local authorities in the Balearic Islands to develop a coastal sea-cleaning boat service covering the region, identifying the floating marine debris, and removing it from the coastal areas. This study considered daily monitoring from May to October spanning from 2005 to 2015. Plastic marine debris composed over 54% of all floating marine debris removed daily across the Balearic Islands. The spatio-temporal patterns indicate a heterogeneous distribution of plastic in the coastal areas, with higher concentrations in the north-western and south-eastern regions of the islands and debris peaking during the month of August. Furthermore, floating marine debris was more easily collected during calm seas as well as using an integrated monitoring approach to facilitate its removal. Overall, sea-cleaning boats are highly effective in removing coastal floating marine debris.
Show more [+] Less [-]Spatio-temporal monitoring of coastal floating marine debris in the Balearic Islands from sea-cleaning boats Full text
2019
Compa, Montserrat | March, David | Deudero, Salud
Mismanaged waste is accumulating at an alarming rate in the marine environment. Its presence has caused local authorities in the Balearic Islands to develop a coastal sea-cleaning boat service covering the region, identifying the floating marine debris, and removing it from the coastal areas. This study considered daily monitoring from May to October spanning from 2005 to 2015. Plastic marine debris composed over 54% of all floating marine debris removed daily across the Balearic Islands. The spatio-temporal patterns indicate a heterogeneous distribution of plastic in the coastal areas, with higher concentrations in the north-western and south-eastern regions of the islands and debris peaking during the month of August. Furthermore, floating marine debris was more easily collected during calm seas as well as using an integrated monitoring approach to facilitate its removal. Overall, sea-cleaning boats are highly effective in removing coastal floating marine debris.
Show more [+] Less [-]Post-release breeding success of oil-rehabilitated and non-rehabilitated little blue penguins, Eudyptula minor, following the M/V Rena oil spill, New Zealand Full text
2019
Sievwright, Karin A. | Battley, Phil F. | McConnell, Helen M. | Chilvers, B. L. (Barbara Louise) | Morgan, Kerri J.
During the 2011 M/V Rena oil spill in Tauranga, New Zealand, 383 little blue penguins (LBP, Eudyptula minor) were oiled, rescued and rehabilitated, with 90.6% surviving to be released back to the wild. We monitored the post-release breeding success of rehabilitated LBPs to assess the effectiveness of the rehabilitation process. Breeding success was monitored during the first breeding season post-release (2012−13) to assess productivity for both rehabilitated and control penguins (breeding pairs of rehabilitated or non-oiled (control) birds). Egg laying, hatching and fledging success rates for pairs of rehabilitated and control penguins were both within ranges reported for other LBP colonies in Australia and New Zealand. The only significant difference between rehabilitated and control pairs was that hatching success was reduced in the first season after release for rehabilitated pairs. Overall, rehabilitation appeared to reverse most potential negative effects of oiling on the post-release breeding success of rehabilitated LBP.
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