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Seasonal variability in plankton food web composition in Tuticorin coastal waters, south east coast of India
2018
Bharathi, M.D. | Patra, Sivaji | Sundaramoorthy, S. | Madeswaran, P. | Chandrasekar, D. | Sundaramanickam, A.
To understand the impact of seasonal variability on plankton food web composition in tropical coastal waters, samples were collected from three locations along Tuticorin coastal waters during postmonsoon, summer, and northeast (NE) monsoon seasons. During the NE monsoon, the total suspended matter (TSM) and nutrient concentrations were relatively higher, whereas salinity and plankton (phytoplankton and zooplankton) abundances were lower. Cluster analysis also revealed that the NE monsoon formed into a separate cluster because of the lower phytoplankton abundance caused by higher loads of TSM; this arrests light penetration, thereby resulting in a decrease in plankton abundance. The increase in zooplankton biomass coincided with the decrease in diatoms (p < 0.05), and the increase in cyanobacteria may reflect that grazers food choice has a significant impact on the base of the food web composition. The present study states that the phytoplankton biomass was greatly influenced by seasonality and associated changes rather than the huge supply of nutrient loads.
Afficher plus [+] Moins [-]Taiwan's legal framework for marine pollution control and responses to marine oil spills and its implementation on T.S. Taipei cargo shipwreck salvage
2018
Fan, Chihhao | Hsu, Cheng-Jui | Lin, Jia-Yu | Kuan, Yung-Kai | Yang, Chieh-Chung | Liu, Ruixiang | Yeh, Jiunn-Horng
Many shipwreck events occur in the neighboring areas of Taiwan due to the volume of maritime traffic and geographical conditions around Taiwan. The oil spills from such events can be devastating for the surrounding sea and coastal areas. The government realized the importance of marine pollution prevention and enforced the Marine Pollution Control Act and the Major Marine Oil Pollution Emergency Response Plan to mitigate the impact of oil spill pollution. The T.S. Taipei shipwreck highlighted the effectiveness of the national marine pollution prevention system. Inter-departmental cooperation and collaboration with private sectors are the keys for effective response. This article is the first detailed documentation of an oil spill response for a maritime incident from the beginning to the final termination of shipwreck removal. It shows the people in Taiwan intend to collaborate with other states to make a significant contribution to marine environment conservation and sustainability.
Afficher plus [+] Moins [-]Persistent organic pollutants in sediments, intertidal crabs, and the threatened Olrog's gull in a northern Patagonia salt marsh, Argentina
2018
Commendatore, Marta | Yorio, Pablo | Scenna, Lorena | Ondarza, Paola M. | Suárez, Nicolás | Marinao, Cristian | Miglioranza, Karina S.B.
Persistent organic pollutants (POPs) are of great concern for the environment. In this study we (a) determine levels and distribution of OCPs, PCBs, and PBDEs in sediments and two crab species (Neohelice granulata and Cyrtograpsus altimanus), (b) assess bioaccumulation in crabs, and (c) explore the occurrence of POPs in the Near Threatened Olrog's gull (Larus atlanticus) chicks and eggs in one of the most important salt marsh environments in the South West Atlantic. Sediments, crabs, and gull chicks and eggs showed POPs presence at low levels; being α-endosulfan, PCB-153, and BDE-47 the most represented compounds. In sediments, pollutant concentrations were lower than those reported in Canadian guidelines for the protection of the aquatic life. POP bioaccumulation was recorded in crabs, suggesting a risk to upper trophic level predators. Further studies are needed to understand the trophic effects of POPs in San Blas bay, particularly on the threatened Olrog's gull.
Afficher plus [+] Moins [-]Dispersal of alien invasive species on anthropogenic litter from European mariculture areas
2018
Rech, Sabine | Salmina, Simone | Borrell Pichs, Yaisel J. | García Vázquez, Eva
The importance of mariculture areas for the dispersal of alien invasive species (AIS) on artificial floating items has recently been highlighted as a priority research need. Here we present the results of surveys in two important European shellfish culture areas that release rafting AIS, the Venetian lagoon and the Portuguese Algarve region. We found eight aquaculture-related non-native, invasive species attached to anthropogenic litter items mostly related to aquaculture: Amphibalanus amphitrite, Austrominius modestus, Balanus trigonus, Hesperibalanus fallax, Hydroides elegans, Hydroides sanctaecrucis, and Magallana angulata. These species are well-adapted to rafting on artificial surfaces and have a high potential to disperse via this vector. This is the first record of the notorious nuisance species H. sanctaecrucis both in the Mediterranean and Eastern Atlantic, as well as on floating litter. We also present the first records of M. angulata, H. sanctaecrucis, Sabellaria alveolata, Mytilus edulis and Chthamalus montagui on stranded anthropogenic litter.
Afficher plus [+] Moins [-]Simultaneous grading of microplastic size sampling in the Small Islands of Bintan water, Indonesia
2018
Syakti, Agung Dhamar | Hidayati, Nuning Vita | Jaya, Yales Veva | Siregar, Sofyan Husein | Yude, Renald | Suhendy, | Asia, Laurence | Wong-Wah-Chung, Pascal | Doumenq, Pierre
Despite Indonesia being considered as second highest source of marine plastic debris in the world, few studies have been conducted on plastic debris in Indonesia, particularly microplastics. By using a simple device to simultaneously grade floating microplastics, we investigated microplastic contamination in the ecosystem of small islands in Bintan Regency, Riau Island Province, Indonesia. The average number of floating microplastics from 11 beach stations around Bintan Island was 122.8 ± 67.8 pieces per station, which corresponds to 0.45 pieces per m3 and represents a low-medium microplastic pollution level compared to the levels of other marine environments worldwide. Polymer identification using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) Spectroscopy successfully identified Polyethylene (PE) (17.3 ± 8.3%), Low Density PE (17.6 ± 5.5%), Oxidized LDPE (<0.1%), Polypropylene (PP) (54 ± 13%), PP Atactic (<0.4%), PP isotactic (<0.2%) and Polystyrene (PS) (10.4 ± 9.1%) from different forms and shapes of microplastics i.e., fragments (50.9 ± 4.9%), fibers (26.2 ± 3%), granule (13.1 ± 3.8%) and films (9.8 ± 5.1%). We suggest that the generation of these microplastics was likely due to physicochemical processes, including biological degradation in this tropical ecosystem. Environmental implication of microplastics in this area increases the problems associated with ingestion, bioaccumulation and biomagnification across trophic levels and co-pollutants absorbed onto microplastics.
Afficher plus [+] Moins [-]The sources and ecological risk assessment of elemental pollution in sediment of Linggi estuary, Malaysia
2018
Elias, Md Suhaimi | Ibrahim, Shariff | Samuding, Kamarudin | Rahman, Shamsiah Ab | Hashim, Azian
In this study, concentrations of heavy metals, rare earth elements (REEs), Uranium (U) and Thorium (Th) of the actinide group were determined from Linggi estuary sediment samples by neutron activation analysis (NAA) and inductive coupled plasma - mass spectrometry techniques. The geo-accumulation (Igeo) and ecological risk index (Ri) values were calculated to identify the quality status of Linggi estuary sediments. Results indicated Linggi estuary was polluted by arsenic (As), lead (Pb) and antimony (Sb). REEs, U and Th showed significant increase of concentration in Linggi estuary sediments. Ri of Linggi estuary was categorised as low to considerable ecological risk, which indicates no significant to moderate effect on the majority of the sediment-dwelling organisms. Correlation matrix and principal component analysis assessed pollution sources to be both natural and anthropogenic.
Afficher plus [+] Moins [-]A preliminary study on coastal debris in Nallathanni Island, Gulf of Mannar Biosphere Reserve, Southeast coast of India
2018
Krishnakumar, S. | Srinivasalu, S. | Saravanan, P. | Vidyasakar, A. | Magesh, N.S.
Nine sampling stations were fixed to carry out the preliminary investigation on coastal debris from Nallathanni island, Gulf of Mannar Biosphere Reserve, Southeast coast of India. The coastal debris were separated and identified using hand picking, visual identification and microscopic studies. The coastal areas of the study region were less dominated by micro plastic contamination. The coastal debris was dominated by polyethylene bottles and fibrous fishnet materials. The distribution of the coastal debris along the coastal region is chiefly controlled by winnowing action of sea waves and Aeolian action along the berm region.
Afficher plus [+] Moins [-]Movement patterns of California brown pelicans (Pelecanus occidentalis californicus) following oiling and rehabilitation
2018
Lamb, J.S. | Fiorello, C.V. | Satgé, Y.G. | Mills, K. | Ziccardi, M. | Jodice, P.G.R.
Direct mortality of wildlife is generally used to quantify the damage caused by pollution events. However, free-ranging wildlife that survive initial exposure to pollutants may also experience long-term consequences. Individuals that are rehabilitated following oil exposure have a known history of oiling and provide a useful study population for understanding behavior following pollution events. We GPS-tracked 12 rehabilitated brown pelicans and compared their movements to those of eight non-oiled, non-rehabilitated controls over 87–707 (mean = 271) days. Rehabilitated pelicans traveled farther, spent more time in long-distance movements, and occupied more productive waters than controls. These differences were more apparent among females than males. Rehabilitated pelicans also visited breeding colonies and nest sites at lower rates than controls. Our results indicate that, although rehabilitated pelicans undertake long-distance movements, they may display increased dispersion and reduced breeding investment, particularly among females. Such behavioral changes could have long-term effects on populations.
Afficher plus [+] Moins [-]Accumulation of quaternary ammonium compounds as emerging contaminants in sediments collected from the Pearl River Estuary, China and Tokyo Bay, Japan
2018
Dai, Xi | Wang, Cuicui | Lam, James C.W. | Yamashita, Nobuyoshi | Yamazaki, Eriko | Horii, Yuichi | Chen, Weifang | Li, Xiaolin
In this work, the distribution of quaternary ammonium compounds (QACs) in two dated sediment cores, collected from the Pearl River Estuary (PRE) and Tokyo Bay (TB), were investigated to understand the historical input of QACs and their diagenetic behavior in urban estuarine environments. The vertical variation profiles of QAC concentrations showed that benzylalkyldimethyl ammonium compounds (BACs) and dialkyldimethyl ammonium compounds (DADMACs) were widely used during 1970s and 1980s both in China and Japan. The declining environmental concentrations of QACs suggested a compositional change of commodities and the effectiveness of emission control strategies. For the individual QAC homologues, BAC homologues decreased significantly over time, while DADMAC compositions remained relatively stable. The differences in concentration and composition profiles of BACs and DADMACs in the sediment cores provided useful information on the patterns of use of QACs in China and Japan, as well as their diagenetic behaviors in the sediments.
Afficher plus [+] Moins [-]Marine litter disrupts ecological processes in reef systems
2018
de Carvalho-Souza, Gustavo F. | Llope, Marcos | Tinôco, Moacir S. | Medeiros, Diego V. | Maia-Nogueira, Rodrigo | Sampaio, Cláudio L.S.
Marine litter (ML) contaminates essentially all global coastal and marine environments and drives multiple ecosystem-level effects. Although deleterious effects of ML on several organisms have been investigated in the last years, this information tends to be dispersed or underreported, even in marine biodiversity hotspots such as reef ecosystems. Two are the main goals of this paper: (i) to integrate and synthesize current knowledge on the interactions of ML and reef organisms, and (ii) to evaluate the multiple disruptions on the ecological processes in reef systems. We report here ML-driven ecological disruptions on 418 species across eight reef taxa, including interactions that were previously not addressed in detail, and evaluate their major conservation implications. These results can help raise awareness of global impacts on the world's reefs by highlighting ML associations in different reef systems around the world, and can aid in ML input reduction and marine management.
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