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Sustainability and the Spanish port system. Analysis of the relationship between economic and environmental indicators
2016
Laxe, Fernando González | Bermúdez, Federico Martín | Palmero, Federico Martín | Novo Corti, Isabel
Research into the methodological development of alternative systems of sustainability measures is recent. In understanding sustainable development in a multi-dimensional sense, one of the most significant advances was the construction of Synthetic Indexes, applicable to different spatial spheres or to organisations, businesses, institutions, etc.The Spanish port system of general interest comprises 46 ports integrated in 28 Port Authorities, which in 2014 moved 482,000,000t of goods and more than 28 million passengers. This gives an idea of its importance for the Spanish economy.Using a derivation of the procedure used to calculate the Port Sustainability Synthetic Index, in this research the analysis of the relationship that exists between the findings obtained for the economic and environmental dimensions is used. This enables the existence of links between ports and economic and environmental indicators for a sample of 16 Port Authorities of Spain to be verified.
Afficher plus [+] Moins [-]Investigation on the differences of accumulating Escherichia coli in three types of shellfish species, involving in the environmental factors
2016
Jin, Lei | Li, Tiejun | Liu, Huan | Zhu, Jinping
This study investigated accumulation of Escherichia coli and aerobic colony count in three types of shellfish species. The results indicated that the capability of accumulating E. coli and aerobic colony count for Sinonovacula constricta was stronger than that for Meretrix meretrix and Tegillarca granosa, and capability of accumulating E. coli for M. meretrix was slightly stronger than that for T. granosa. However, no significant difference was observed in the capability of accumulating aerobic colony count between M. meretrix and T. granosa. Moreover, accumulation of E. coli in S. constricta is affected by contaminated seawater and E. coli were accumulated much faster and more in S. constricta when the seawater contaminated more serious. Meanwhile, the results suggested that the populations of E. coli in S. constricta changed in accordance with the weather. This is the first study to investigate the differences of accumulating E. coli in three types of shellfish species.
Afficher plus [+] Moins [-]Preliminary investigation of perfluoroalkyl substances in exploited fishes of two contaminated estuaries
2016
Taylor, Matthew D. | Johnson, Daniel D.
Perfluoroalkyl substances (PFASs) are being increasingly detected in a range of aquatic and terrestrial ecosystems, often resulting from the use of legacy fire-fighting foams. This study conducted an initial investigation of the concentrations of PFASs in the commercially and recreationally exploited species Dusky Flathead, Mud Crab, School Prawn, Sea Mullet, Yellowfin Bream, Eastern King Prawn and Sand Whiting, across two contaminated estuaries. All samples contained perfluoro-n-octane sulfonate (PFOS) except four Yellowfin Bream samples (two from each estuary). Perfluoro-n-octanoic acid (PFOA) was detected only in School Prawn samples from Fullerton Cove, while perfluoro-n-hexane sulfonate (PFHxS) was detected in prawn muscle and in fish liver samples from both estuaries. This study presents one of the first surveys of PFAS in a range of edible saltwater fish and crustaceans in Australia, and these baseline levels of contamination will prove useful for informing future surveys of these emerging contaminants.
Afficher plus [+] Moins [-]Use of Amendments to Restore Ecosystem Function to Metal Mining-Impacted Sites: Tools to Evaluate Efficacy
2016
Brown, Sally L. | Chaney, Rufus L.
As in situ use of amendments for restoration of metal-contaminated mining sites becomes increasingly accepted, the expected level of ecosystem function at these sites will increase. Use of appropriate tools to measure both the level and value of that function is critical to expand use of this approach. For these sites, amendment mixtures must reduce metal availability in situ and restore ecosystem function. Combinations of mixtures, typically consisting of a material with high metal binding capacity (cyclonic ashes, municipal biosolids, or other materials rich in Fe, Al, or Mn oxides), material to adjust soil pH (sugar beet lime, cement kiln dust, dolomitic limestone), and an organic residual to provide soil structure and nutrients (composts, animal manures, municipal biosolids) have been tested in multiple lab and field trials on metal-contaminated sites. This review focuses on field tests of this approach with the goal of providing methods to quantify reduction of hazard and restoration of functional systems. Methods to evaluate success of amendments including extractions to measure changes in metal availability, microbial function and diversity, phytoavailability of metals, and earthworm and small mammal assays are discussed. In most cases, measures of metal availability and ecosystem function are related. For example, surveys of small mammals on restored sites provide information on metal availability as well as suitability of restored habitat. Additional measures of ecosystem function including soil fertility, physical properties, and diversity of habitat are described. Finally, measures of the value of this approach for restoring ecosystems are detailed.
Afficher plus [+] Moins [-]Measures for environmental conservation in enclosed coastal seas
2016
Tomita, Akio | Nakura, Yoshio | Ishikawa, Takuya
With putting a focus on the balance among the nutrient salts such as nitrogen and phosphorus, the Ministry of the Environment (MOE) developed the Action Plan for Healthy Material Circulation in Ocean (just called the Healthy Plan). The plan aims to facilitate the healthy and smooth circulation of the nutrients with an integrated management over land and sea as a package in respective sea areas. The Healthy Plan is now in a pilot phase and is to be implemented for some selected model regions.Meanwhile, devastating tsunamis caused by the Great East Japan Earthquake on March 11th, 2011 severely damaged the natural environments in the affected regions. In the affected bays, seaweed beds and spawning grounds disappeared in a blink. MOE has launched on the recovery activities of Zostera (eelgrass) beds, using the concepts and the methods used in the “Sato-umi Creation” activity which is a purposeful environmental recovery project.
Afficher plus [+] Moins [-]Distribution and contamination assessment of heavy metals in surface sediments of the Luanhe River Estuary, northwest of the Bohai Sea
2016
Liu, Jinqing | Yin, Ping | Chen, Bin | Gao, Fei | Song, Hongying | Li, Meina
33 surface sediment samples from the Luanhe River Estuary have been analyzed for heavy metals to evaluate the spatial distribution pattern and their potential ecological risk. Higher metal concentrations were found in the river mouth and southern areas where being covered by fine particulate matters. In comparison with the threshold effect level and the probable effect level, Cu, Pb, Cr, Ni, and As had occasionally adverse biological effects on the aquatic ecosystems. Both the enrichment factor and geoaccumulation index values show that all the regions have been weakly polluted by Pb, Hg, As, and Cd with an exception of being moderately to strongly polluted by Hg in the river mouth and southern areas. The sources of Zn, Ni, Cd, Hg, and Cr were mainly from the river input and coastal discharge, whereas Cu, Pb, and As were mainly derived from vehicle emissions, coal and oil combustion.
Afficher plus [+] Moins [-]Dynamics of phytoplankton communities in eutrophying tropical shrimp ponds affected by vibriosis
2016
Lemonnier, Hugues | Lantoine, François | Courties, Claude | Guillebault, Delphine | Nézan, Elizabeth | Chomérat, Nicolas | Escoubeyrou, Karine | Galinié, Christian | Blockmans, Bernard | Laugier, Thierry
Tropical shrimp aquaculture systems in New Caledonia regularly face major crises resulting from outbreaks of Vibrio infections. Ponds are highly dynamic and challenging environments and display a wide range of trophic conditions. In farms affected by vibriosis, phytoplankton biomass and composition are highly variable. These conditions may promote the development of harmful algae increasing shrimp susceptibility to bacterial infections. Phytoplankton compartment before and during mortality outbreaks was monitored at a shrimp farm that has been regularly and highly impacted by these diseases. Combining information from flow cytometry, microscopy, pigment and phylogenetic analysis, the presence of Picocyanobacteria, Prasinophyceae and Diatomophyceae were detected as dominant phytoplankton groups and Cryptophyceae, Prymnesiophyceae and Dinophyceae as minor components. At the onset of the first shrimp mortalities, Bacillariophyceae increased while Cyanobacteria, Prymnesiophyceae and Dinophyceae decreased in the water column, followed by proliferation of Prasinophyceae. Several taxa were identified as potential harmful algae (Cyanobacteria, dinoflagellates and Phaeocystis).
Afficher plus [+] Moins [-]Ingestion of microplastics by demersal fish from the Spanish Atlantic and Mediterranean coasts
2016
Bellas, Juan | Martínez-Armental, José | Martínez-Cámara, Ariana | Besada, Victoria | Martínez-Gómez, Concepción
Microplastic pollution has received increased attention over the last few years. This study documents microplastic ingestion in three commercially relevant demersal fish species from the Spanish Atlantic and Mediterranean coasts, the lesser spotted dogfish Scyliorhinus canicula, the European hake Merluccius merluccius and the red mullet Mullus barbatus. Overall 212 fish were examined, 72 dogfish, 12 hakes and 128 red mullets. The percentage of fish with microplastics was 17.5% (15.3% dogfish, 18.8% red mullets and 16.7% hakes), averaging 1.56±0.5 items per fish, and the size of the microplastics ranged from 0.38 to 3.1mm. These fish species are used currently as biomonitors for marine pollution monitoring within the Spanish Marine Pollution Monitoring Programme (SMP), and may be as well suitable candidates for monitoring spatial and temporal trends of ingested litter. The data presented here represent a baseline for the implementation of the Marine Strategy Framework Directive descriptor 10 in Spain.
Afficher plus [+] Moins [-]Composition and temporal stability of turf sediments on inner-shelf coral reefs
2016
Gordon, Sophie E. | Goatley, Christopher H.R. | Bellwood, David R.
Elevated sediment loads within the epilithic algal matrix (EAM) of coral reefs can increase coral mortality and inhibit herbivory. Yet the composition, distribution and temporal variability of EAM sediment loads are poorly known, especially on inshore reefs. This study quantified EAM sediment loads (including organic particulates) and algal length across the reef profile of two bays at Orpheus Island (inner-shelf Great Barrier Reef) over a six month period. We examined the total sediment mass, organic load, carbonate and silicate content, and the particle sizes of EAM sediments. Throughout the study period, all EAM sediment variables exhibited marked variation among reef zones. However, EAM sediment loads and algal length were consistent between bays and over time, despite major seasonal variation in climate including a severe tropical cyclone. This study provides a comprehensive description of EAM sediments on inshore reefs and highlights the exceptional temporal stability of EAM sediments on coral reefs.
Afficher plus [+] Moins [-]Small-scale temporal and spatial variability in the abundance of plastic pellets on sandy beaches: Methodological considerations for estimating the input of microplastics
2016
Moreira, Fabiana Tavares | Prantoni, Alessandro Lívio | Martini, Bruno | de Abreu, Michelle Alves | Stoiev, Sérgio Biato | Turra, Alexander
Microplastics such as pellets have been reported for many years on sandy beaches around the globe. Nevertheless, high variability is observed in their estimates and distribution patterns across the beach environment are still to be unravelled. Here, we investigate the small-scale temporal and spatial variability in the abundance of pellets in the intertidal zone of a sandy beach and evaluate factors that can increase the variability in data sets. The abundance of pellets was estimated during twelve consecutive tidal cycles, identifying the position of the high tide between cycles and sampling drift-lines across the intertidal zone. We demonstrate that beach dynamic processes such as the overlap of strandlines and artefacts of the methods can increase the small-scale variability. The results obtained are discussed in terms of the methodological considerations needed to understand the distribution of pellets in the beach environment, with special implications for studies focused on patterns of input.
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