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Long term monitoring of photosystem II herbicides – Correlation with remotely sensed freshwater extent to monitor changes in the quality of water entering the Great Barrier Reef, Australia 全文
2012
Kennedy, Karen | Schroeder, Thomas | Shaw, Melanie | Haynes, David | Lewis, Stephen | Bentley, Christie | Paxman, Chris | Carter, S. (Steve) | Brando, Vittorio E. | Bartkow, Michael | Hearn, Laurence | Mueller, Jochen F.
Photosystem II (PSII) herbicides are used in large quantities on agricultural lands adjoining the Great Barrier Reef (GBR). Routine monitoring at 14 sites in inshore waters of the GBR using passive sampling techniques detected diuron (32–94% of sampling periods) at maximum concentrations of 1.7–430ngL⁻¹ in the relatively pristine Cape York Region to the Mackay Whitsunday Region, respectively. A PSII herbicide equivalent (PSII-HEq) index developed as an indicator for reporting was dominated by diuron (average contribution 89%) and typically increased during the wet season. The maximum PSII-HEq indicates the potential for photosynthetic inhibition of diatoms, seagrass and coral-symbionts. PSII herbicides were significantly positively correlated with remotely sensed coloured dissolved organic matter, a proxy for freshwater extent. Combining these methods provides for the first time the potential to cost-effectively monitor improvements in water quality entering the GBR with respect to exposure to PSII herbicides.
显示更多 [+] 显示较少 [-]CYP4 mRNA expression in marine polychaete Perinereis aibuhitensis in response to petroleum hydrocarbon and deltamethrin 全文
2012
Chen, Xue | Zhou, Yibing | Yang, Dazuo | Zhao, Huan | Wang, Lili | Yuan, Xiutang
A CYP4 cDNA was cloned and characterized to identify the relationship between persistent organic pollutants and stress response in marine polychaete Perinereis aibuhitensis. The full length of PaCYP4 cDNA is 1857bp and encodes 481 amino acids. The deduced amino acid sequence showed 73% identity with CYP4BB1 from polychaete Nereis virens and shared high homology to other known CYP4 sequences. The expression level of PaCYP4 under petroleum hydrocarbon (PH) and deltamethrin (DM) exposure was detected using Real-time PCR. PH and combined toxicity treatments elevated the mRNA level of PaCYP4 in a dose- and time-dependent manner. The mRNA transcripts of PaCYP4 increased at the beginning of DM exposure and then eventually decreased, and the expression level of PaCYP4 down-regulated with increasing concentration of DM. CYP4 in P. aibuhitensis plays an important role in the metabolism of petroleum hydrocarbon and organochlorine pesticide.
显示更多 [+] 显示较少 [-]Sedimentary records of metal contamination and eutrophication in Jinhae-Masan Bay, Korea 全文
2012
Lim, Dhong-il | Jung, Hoi Soo | Kim, Kyung Tae | Shin, Hyeon Ho | Jung, Seung Won
Historical environmental pollution in a semi-enclosed coastal bay was investigated using high-resolution sedimentary records for Cₒᵣg, Nₜₒₜ, CaCO₃, δ¹³C, and δ¹⁵N signatures, and trace metals. A temporal increase in organic matter might have been attributable to enhanced primary marine productivity, presumably caused by increased anthropogenic nutrient inputs in the semi-enclosed, eutrophic system. Metal accumulation occurred in three stages: a preindustrial stage before the 1930s with natural concentrations of metals, an industrialization stage (1940s–1970s) with the highest concentrations, and a postindustrial stage (post 1970s) with stable or decreasing concentrations. However, Hg exhibited a different accumulation history, with concentrations increasing in the early 1900s and accelerating after the 1920s, probably in response to coal burning.
显示更多 [+] 显示较少 [-]Regional assessment of PAHs contamination in SE Brazil using brown mussels (Perna perna Linnaeus 1758) 全文
2012
Yoshimine, Renato V. | Carreira, Renato S. | Scofield, Arthur L. | Wagener, Angela L.R.
Cultured and native brown mussels (Perna perna Linnaeus 1758) were used to evaluate the contamination by PAHs in the SE Brazilian coastal zone. Mean concentrations of total PAH (38 parental and alkylated compounds) and cluster analysis revealed that: (i) mussel farms (32.7–70.1ngg⁻¹) are located in uncontaminated areas; (ii) coastal rockyshore areas (89.7±25.8ngg⁻¹) have low level of contamination; and (iii) the Guanabara Bay (760.9±456.3ngg⁻¹) is chronically contaminated by hydrocarbons, which is consistent with previous results. PAH profiles and diagnostic ratios suggested mixed petrogenic and pyrolitic sources for group (ii) and petrogenic sources for group (iii). The levels of PAH in the cultured and native mussels are below threshold values for safe food, even in Guanabara Bay, and thus in such cases other contaminants and pathogens should be considered in order to evaluate the quality of shellfish for human consumption.
显示更多 [+] 显示较少 [-]Persistent organic pollutants in the endangered Hawaiian monk seal (Monachus schauinslandi) from the main Hawaiian Islands 全文
2012
Bohlander, Jessica | Boyd, Daryle | Ylitalo, Gina M. | Littnan, Charles | Pearce, R. (Ronald)
Little is known about levels or effects of persistent organic pollutants (POPs) in Hawaiian monk seals (HMS) from the main Hawaiian Islands (MHI) subpopulation. This study examined concentrations of a large suite of POPs in blubber and serum of juvenile and adult HMS from the MHI. Adult females have the lowest blubber levels of most POPs, whereas adult males have highest levels. POPs in serum were significantly different in adult males compared with adult females for chlordanes and summed dichlorodiphenyltrichloroethanes (DDTs). Lipid-normalized concentrations of chlordanes, DDTs, polychlorinated biphenyls, and mirex in paired blubber and serum samples were significantly correlated. Contaminant levels from the MHI were at similar or lower levels than those from remote Northwestern Hawaiian Island populations. Determining initial ranges of POPs is an important step towards assessing one of the many potential health threats to this critically endangered species.
显示更多 [+] 显示较少 [-]Twenty years of Belgian North Sea aerial surveillance: A quantitative analysis of results confirms effectiveness of international oil pollution legislation 全文
2012
Lagring, Ruth | Degraer, Steven | de Montpellier, Géraldine | Jacques, Thierry | Van Roy, Ward | Schallier, Ronny
Over the years many policy measures have been taken to prevent illegal oil discharges from ships, like the MARPOL 73/78 Convention (1983) and the Bonn Agreement (1969/1983). However, the number of discharges remained high, leading to chronic oiling of seabirds and sensitive coastlines, therefore further measures were taken. The aim of this study is to quantify the effectiveness of two key legislative regulations: the IMO-designation of the North Sea as MARPOL Special Area which took effect in 1999, and the adoption of the EU Directive on Port Reception Facilities in 2000. Under study is the heavily navigated Belgian Surveillance Area, monitored since 1991, characterised by shallow waters with ecologically important sandbanks. The aerial surveillance data from 1991 to 2010 show a stepwise decrease in ship-source oil pollution. Three time periods can be distinguished with two turning points coinciding with the actual implementation of these key legislative measures, confirming their effectiveness.
显示更多 [+] 显示较少 [-]Pigmentation of massive corals as a simple bioindicator for marine water quality 全文
2012
Cooper, Timothy F. | Fabricius, Katharina E.
Photo-acclimatisation by the algal endosymbionts of scleractinian corals to changes in environmental conditions may influence their density and/or the concentration of photosynthetic pigments, and hence coral brightness, on short time-scales. To examine coral pigmentation as a bioindicator of water quality, the brightness of massive corals was quantified using colour charts, concentrations of the pigment chlorophyll a and reflectance spectrometry in the field and with manipulative experiments. Along a water quality gradient, massive Porites became progressively lighter as nutrients decreased and irradiance increased. A laboratory experiment showed that Porites nubbins darkened within 25days following exposure to reduced water quality. The results of a transplantation experiment of Porites nubbins in a manipulation incorporating multiple depths and zones of water quality confirmed colony brightness as a simple tool to monitor changes in marine water quality, provided effects due to other influences on pigmentation, e.g. seawater temperatures, are taken into consideration.
显示更多 [+] 显示较少 [-]The effect of in situ shading on a Posidonia oceanica meadow situated within a fish farm induced moderately nutrient enriched environment 全文
2012
Puhr, Kristian | Pikelj, Kristina
The aim of this research was to explore the possibility of a successful and balanced integration of fish farming installations into an ecosystem dominated by Posidonia oceanica (L.) Delile species. We selected light, temperature, seabed topography, sediment characteristics, meadow density, bottom coverage, maximum leaf length and lower depth limit as principle components in assessing the influence of the fish farm. All P. oceanica descriptors showed significant correlation with light deprivation effect while sediment organic matter content revealed slightly higher values than normal, increasing with distance from the cages. The results point to a conclusion that in such lightly nutrient enriched ecosystems, the seagrass growth and distribution are principally controlled by the shadow that cages cast on the seabed below, and that when carefully planned, fish farms do not necessarily degrade the health status of the surrounding area, but in fact facilitate a transition into a secondary stable state.
显示更多 [+] 显示较少 [-]Thermal treatment as a method to control transfers of invasive biofouling species via vessel sea chests 全文
2012
Piola, Richard F. | Hopkins, Grant A.
This study examined the efficacy of heated seawater for the treatment and remediation of fouled vessel sea chest habitats. In laboratory trials, three temperature regimes (37.5°C for 60min, 40°C for 30min and 42.5°C for 20min) were tested on a range of temperate taxa commonly found in sea chests. Field validation trials further assessed the efficacy of heat treatment within a replica sea chest environment. During laboratory trials, 100% mortality was achieved across all three treatments for the majority of taxa; the exceptions being the barnacle Elminius modestus and the oyster Crassostrea gigas. Temperature tolerance limits observed in the laboratory were successfully replicated under simulated sea chest conditions; however, a failure to achieve even heat distribution was an obstacle to achieving uniform mortality. This study provides guidance on the temperature/exposure parameters required for vessels plying temperate latitudes, and demonstrates that heated seawater has potential for controlling biofouling in vessel sea chests.
显示更多 [+] 显示较少 [-]The cumulative impacts of reclamation and dredging on the marine ecology and land-use in the Kingdom of Bahrain 全文
2012
Zainal, Khadija | Al-Madany, Ismail | Al-Sayed, Hashim | Khamis, Abdelqader | Al Shuhaby, Suhad | Al Hisaby, Ali | Elhoussiny, Wisam | Khalaf, Ebtisam
This article assesses the ecological and economic impacts of land reclamation and dredging through consulting recent environmental impact assessment reports. Geographic features of Bahrain during 1963–2008 are produced using Geographical Information System. Extensive but inexpensive shallow coastal areas and tidal flats have been reclaimed particularly from 1997 to 2007 at a high rate of 21km²/year. Formal records show the increase in the original land mass by the year 2008 to be 91km². An estimated total cumulative loss of major habitats resulting from 10 reclamation projects was around 153.58km². Also much larger scale impacts should be considered resulting from the borrow areas used for the extraction of sand or infill materials. A number of key habitats and species are affected in the vicinity of these projects. The study attempts to assign a monetary value to the marine ecosystem functions. There is a need for efficient coastal zone management to regulate a sustainable use of the marine resources.
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