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Effects of CO2 on benthic biota: An in situ benthic chamber experiment in Storfjorden (Norway) Full text
2013
Ishida, Hiroshi | Golmen, Lars G. | West, Julia | Kruger, Martin | Coombs, Patricia | Berge, John Arthur | Fukuhara, Tastuo | Magi, Michimasa | Kita, Jun
Carbon capture and storage (CCS) methods, either sub-seabed or in ocean depths, introduces risk of CO2 leakage and subsequent interaction with the ecosystem. It is therefore important to obtain information on possible effects of CO2. In situ CO2 exposure experiments were carried out twice for 10days during 2005 using a Benthic Chamber system at 400m depth in Storfjorden, Norway. pCO2 in the water above the sediment in the chambers was controlled at approximately 500, 5000 and 20,000μatm, respectively. This article describes the experiment and the results from measured the biological responses within the chamber sediments. The results show effects of elevated CO2 concentrations on biological processes such as increased nanobenthos density. Methane production and sulphate reduction was enhanced in the approximately 5000μatm chamber.
Show more [+] Less [-]Environmental perverse incentives in coastal monitoring Full text
2013
Gibbs, Mark T.
It can be argued that the intensity of monitoring of coastal marine environments lags behind the equivalent terrestrial environments. This results in a paucity of long-term time series of key environmental parameters such as turbidity. This lack of management information of the sources and sinks, and causes and impacts of stressors to the coastal marine environment, along with a lack of co-ordination of information collection is compromising the ability of environmental impact assessments of major coastal developments to discriminate between local and remote anthropogenic impacts, and natural or background processes. In particular, the quasi outsourcing of the collection of coastal information can lead to a perverse incentive whereby in many cases nobody is actively or consistently monitoring the coastal marine environment effectively. This is particularly the case with regards to the collection of long-term and whole-of-system scale data. This lack of effective monitoring can act to incentivise poor environmental performance.
Show more [+] Less [-]Bioavailability of heavy metals in water and sediments from a typical Mediterranean Bay (Málaga Bay, Region of Andalucía, Southern Spain) Full text
2013
Alonso Castillo, M.L. | Sánchez Trujillo, I. | Vereda Alonso, E. | García de Torres, A. | Cano Pavón, J.M.
Concentrations of heavy metals were measured in sediment and water from Málaga Bay (South Spain). In the later twentieth century, cities such as Málaga, have suffered the impact of mass summer tourism. The ancient industrial activities, and the actual urbanization and coastal development, recreation and tourism, wastewaters treatment facilities, have been sources of marine pollution. In sediments, Ni was the most disturbing metal because Ni concentrations exceeded the effects range low (ERL), concentration at which toxicity could start to be observed in 85% of the samples analyzed. The metal bioavailability decreased in the order: Cd>Ni>Pb>Cu>Cr. In the sea water samples, Cd and Pb were the most disturbing metals because they exceeded the continuous criteria concentration (CCC) of US EPA in a 22.5% and 10.0% of the samples, respectively. Statistical analyses (ANOVA, PCA, CA) were performed.
Show more [+] Less [-]Distributions, possible sources and biological risk of DDTs, HCHs and chlordanes in sediments of Beibu Gulf and its tributary rivers, China Full text
2013
Xu, Yiyin | Wang, Yinghui | Li, Jun | Liu, Xiang | Zhang, Ruijie | Guo, Songjun | Huang, Wenyu | Zhang, Gan
Thirty-five surface sediment samples collected from Beibu Gulf and its tributary rivers, China were analyzed for DDTs, HCHs and chlordanes. Total concentrations of DDTs, HCHs and chlordanes in sediments ranged from 0.59 to 126ngg−1, ND to 2.65ngg−1 and 0.27 to 3.41ngg−1 based on dry weight (dw), respectively. Concentrations of DDTs were higher than those reported in the sediments from other regions of the world, while concentrations of HCHs and chlordanes were relatively low. High concentrations of DDTs were observed in the harbor region and aquaculture bases and high concentrations of HCHs were found in the Qin River Estuary. The ratios of (DDE+DDD)/DDTs reflected a mixed input of weathered and fresh DDTs. The predominant β-HCH indicated that HCHs in the study area mainly originated from the historical usage of technical HCH. The residues of DDTs would pose adverse biological effects on the study area.
Show more [+] Less [-]Habitat degradation correlates with tolerance to climate-change related stressors in the green mussel Perna viridis from West Java, Indonesia Full text
2013
Wendling, Carolin Charlotte | Huhn, Mareike | Ayu, Nurina | Bachtiar, Ramadian | Juterzenka, Karen von | Lenz, Mark
It is unclear whether habitat degradation correlates with tolerance of marine invertebrates to abiotic stress. We therefore tested whether resistance to climate change-related stressors differs between populations of the green mussel Perna viridis from a heavily impacted and a mostly pristine site in West Java, Indonesia. In laboratory experiments, we compared their oxygen consumption and mortality under lowered salinity (−13 and −18 units, both responses), hypoxia (0.5mg/l, mortality only) and thermal stress (+7°C, mortality only). Mussels from the eutrophied and polluted Jakarta Bay showed a significantly smaller deviation from their normal oxygen consumption and higher survival rates when stressed than their conspecifics from the unaffected Lada Bay. This shows that human induced habitat degradation correlates with mussel tolerance to environmental stress. We discuss possible mechanisms – e.g. the selection of tolerant genotypes or habitat-specific differences in the nutritional status of the mussels – that could explain our observation.
Show more [+] Less [-]A bi–level model for transferable pollutant prices to mitigate China’s interprovincial air pollution control problem Full text
2013
Zhao, Laijun | Xue, Jian | Li, Changmin
In this paper, we develop a bi–level transferable air pollutant price (TAPP) model, and use the model to find ways to mitigate China’s interprovincial air pollution control problem. In this model, the leader is China’s central government and the followers consist of China’s 31 provinces. The leader aims to decrease the nation’s total pollutant control costs, whereas each province attempts to minimize its pollution control costs by balancing its own pollutant reduction cost with transfer payments to or from other provinces, in the context of a transfer price set by the leader. We chose a Karush–Kuhn–Tucker approach with an embedded bisection algorithm to solve the model. We then applied the TAPP model to the seriously polluted Beijing–Tianjin–Hebei area of China. Compared with the current command–and–control regulation approach, the TAPP model for the Beijing–Tianjin–Hebei area decreased the total environmental cost by US$ 3 964.61×103 (10.5% of the current command–and–control regulation cost). This demonstrated that the TAPP model was superior because it both mitigated the problem of air pollution transport across regional boundaries and utilized the available resources of the study area more efficiently.
Show more [+] Less [-]Levels of phenolic compounds in Tibouchina pulchra after fumigation with ozone Full text
2013
da Rosa Santos, Ana Clara | Furlan, Claudia Maria
Tibouchina pulchra (Cham.) Cogn. (Melastomataceae) is a native tree species from the southeast region of Brazil. This early successional species significantly contributes to the characteristic physiognomy and structure of the Atlantic Rain Forest. Saplings were exposed to carbon filtered air (CF), ambient non–filtered air (NF), and ambient non–filtered air +40 ppb ozone (NF+O3), 8 h per day during two months, using open top chambers (OTC). The AOT40 values at the end of the experiment were 48, 910 and 12 895 ppb h–1, respectively for each treatment. After 25 days of exposure, interveinal red stippling appeared in plants in the NF+O3 chamber (AOT40=3 871 ppb h–1). In the NF chamber, symptoms were observed only after 60 days of exposure (AOT40=910 ppb h–1). No changes were observed for total phenolic contents when comparing ozone treatments. However, amounts of tannins and flavonoids were different among treatments. NF+O3 and NF treatment showed enhanced contents of flavonoids, when tannins seem to be reduced after ozone fumigation (p<0.01). Results suggest alteration on phenolic metabolism when saplings are ozone fumigated; those responses, considered T. pulchra, seem to occur before leaf injury appeared, once contents of flavonoids and tannins are also altered by NF treatment (AOT40=910 ppb h–1). This study demonstrates that total phenolic and tannins contents of saplings of T. pulchra also decreased when exposed to ozone. The same alterations were observed for T. pulchra after industrial air pollution, suggesting the reduction on total phenolic and tannins probably is a characteristic response of T. pulchra to presence of any kind of pollutant.
Show more [+] Less [-]Artificial radionuclides 90Sr and 241Am in the sediments of the Baltic Sea: Total and spatial inventories and some temporal trends Full text
2013
Hutri, Kaisa-Leena | Mattila, Jukka | Ikäheimonen, Tarja Tuulikki | Vartti, Vesa-Pekka
The Baltic Sea was contaminated by radioactivity following global nuclear fallout and later by the Chernobyl accident. Despite the decrease of radioactivity caused by radioactive decay, radionuclides have a prolonged residence time in the water of the Baltic Sea due to slow water exchange and relatively rapid sedimentation. Very little is known about the amounts or spatial differences of 90Sr and 241Am in the Baltic Sea sediments. In this study, 20 sediment cores taken around the Baltic Sea were investigated to estimate inventories of these radionuclides. The rough results show that the Chernobyl fallout added the amount of 90Sr in the same areas where the increase of 137Cs can be detected, whereas this is not the case for 241Am which is more evenly distributed in the sea bottom. In addition, local differences occur in the concentrations. These results are an important amendment to the radioactivity baseline of the Baltic Sea.
Show more [+] Less [-]Trace element contamination in the estuarine sediments along Tuticorin coast – Gulf of Mannar, southeast coast of India Full text
2013
Magesh, N.S. | Chandrasekar, N. | Krishnakumar, S. | Glory, M.
Sediment samples were collected from Kallar, Korampallam creek and Punnakayal estuaries of Tuticorin coast for assessing the level of contamination by trace elements in these estuarine sediments. The trace element concentration, calcium carbonate, organic carbon and mercury level were analyzed by Inductively Coupled Plasma Atomic Emission Spectrophotometer, Titrimetric method and SnCl2 reduction method. The results reveals that the enrichment factor, metal pollution index and geo-accumulation index of these estuarine sediments were predominantly polluted by Cd, As, Zn, Hg and Pb. The factor analysis revealed the source of trace element accumulation in the estuarine sediments particularly Mn and Fe are from riverine inputs and As and Hg from untreated industrial effluents. Among the selected estuaries, Korampallam creek was found to be highly contaminated by trace elements due to the discharge of effluents from thermal power plant, Tuticorin alkali chemicals, copper smelting, Petrochemical industries and shipping activities.
Show more [+] Less [-]Interspecific introgression and changes in population structure in a flatfish species complex after the Prestige accident Full text
2013
Crego-Prieto, V. | Danancher, D. | Campo, D. | Pérez, J. | Garcia-Vazquez, E. | Roca, A.
Oil spills cause aggressive impacts on marine ecosystems affecting immense areas and the species inhabiting them. If wastes are not cleaned up properly, the remnants may affect local populations for a long time. This work focuses on the long-term impacts of the Prestige spillage that occurred off Galician coast (Spain) in November 2002. Model species were two sympatric flatfish, the megrims Lepidorhombus whiffiagonis and Lepidorhombus boscii. Samples obtained before and nine years after the Prestige accident from affected and unaffected areas were genotyped for six hypervariable nuclear markers and for the mitochondrial D-loop sequence. The results revealed a high proportion of post-F1 interspecific hybrids in the area affected, and also increased intraspecific population differentiation likely due to such localized introgression of foreign genes. These changes suggest the appearance of a hybrid zone following the accident and emphasize the need of paying special attention to potential evolutionary impacts of oil spills.
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