bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trace metals and rare earth elements in Rock Oyster Saccostrea cucullata along the east coast of Peninsular Malaysia
Authors: Fuad M. M. , Shazili N. A. M. , Faridah M. 
Published: October 2017

Trace metals and rare earth elements (REEs) in the soft tissue of rocky shore Rock Oyster, Saccostrea cucullata, along the east coast of Peninsular Malaysia were determined. Significant inter-spatial variations ( p &lt; 0.05) in trace metals and REEs were recorded. Significant positive correlations ( p &lt; 0.01) were found among REEs concentrations. A few significant correlations were found for trace metals and REEs. Average distribution of metals indicated that Johor State had the highest concentrations compared with Pahang and Terengganu for all metals, except for Pb and Cu. This could most likely be attributed to the highly urbanized and industrialized activities such as sewage discharge.
The metal accumulation patterns in the oyster indicated enrichment of essential metals. Sites with relatively high concentrations of the contaminant metals Hg, Cu, Pb and Zn were related to their close proximity to industrial and urban sites or to boating and aquaculture activities. Relative enrichment of Cu, Pb and Zn in oysters in the whole study even from relatively pristine areas is thought to be derived from natural sources as these metals are significantly correlated to REEs distribution. The distribution of REEs show close similarity between all sampling sites, suggesting that they are of similar origins. In all sites, typical saw-tooth chondrite-normalized patterns were observed, which strongly suggested the REEs bioaccumulated in oyster tissues is derived from geogenic sources. Typical deviations from this pattern were found for Ce and Eu and could be explained by their redox chemistry. Results of light to heavy REEs (LREE/HREE) ratios suggested REEs fractionation in coastline marine environment produced more light REEs and less heavy REEs absorbed in the soft tissue of S. cucullata. The ratio of La/Yb in the oyster of 27.3 was remarkably similar to Terengganu River basin soil of 33.0 and to Terengganu River sediment of 27.6. Comparison of metal concentration with maximum permissible limits of toxic metals in food established in different countries, as well as Malaysian Food Act 1983 and Food Regulations 1985 Fourteen Schedule, indicated values were well within safety levels, except for Cu and Zn. Along with its wide distribution on rocky shore areas along the east coast, the present results of trace metals and REEs recorded in soft tissue of S. cucullata collected from 14 sites along the east coast of Peninsular Malaysia served as baseline data for future reference.
Modelling the photochemical generation kinetics of 2-methyl-4-chlorophenol, an intermediate of the herbicide MCPA (2-methyl-4-chlorophenoxyacetic acid) in surface waters
Authors: De Laurentiis Elisa , Minella Marco , Bodrato Marco , Maurino Valter , Minero Claudio , Vione Davide 
Published: October 2017

2-Methyl-4-chlorophenol (MCP) is the main transformation intermediate of the herbicide MCPA in surface waters and it is more toxic than its parent compound. MCP is produced from MCPA by both direct photolysis and •OH reaction. The latter process has higher yield of MCP from MCPA: 0.5 vs. 0.3 for the direct photolysis. Our model results show that the formation rate of MCP would be higher in waters that contain low organic matter and high nitrate and nitrite. Such conditions are favourable to MCPA direct photolysis and •OH-induced transformation, which are both inhibited by organic matter, while •OH formation is enhanced by nitrate and nitrite. Good agreement is obtained between model predictions and field data of MCPA transformation in the Rhône river delta (Southern France). The field data also suggest that MCP undergoes slightly faster transformation than MCPA in that environment.
Planktonic community metabolism in two stratified Mediterranean reservoirs with different trophic status
Authors: Romero-Martínez Leonardo , Morales-Pineda María , Úbeda Bárbara , Loiselle Steven A. , Cózar Andrés , Gálvez José A. 
Published: October 2017

Community metabolism plays a crucial role in the carbon dynamics of continental aquatic ecosystems. In the present work, two Mediterranean reservoirs (Southern Spain) with different trophic status were monitored during the stratified phase over two consecutive years (2009 and 2010) to evaluate community metabolic dynamics and potential controlling factors. Dark and light incubations were performed in order to estimate the daily rates of gross production (GP), community respiration (CR) and net community production (NCP). Temperature, irradiance, chlorophyll, phosphorus and carbon concentration were also measured at different depths within the mixed layer. On average, results showed heterotrophic behavior (GP &lt; CR) in both reservoirs, which was particularly evident in the more eutrophic reservoir. Interannual climate variability was high due to the exceptionally rainy winter of 2010. This resulted in a significant decrease in the magnitude of the heterotrophic balance in both reservoirs. The change in NCP was especially evident in the most eutrophic reservoir where high water renewal rates lead to a lower CR. In general, NCP was found to be directly related to the ratio between the euphotic layer depth and the mixed layer depth, and inversely related to the particulate phosphorus concentration. Autotrophic behavior was only found in conditions of high irradiance (mixed layer shallower than euphotic layer), relatively low concentrations of dissolved organic carbon (&lt;6 mg L−1) and particulate phosphorus (&lt;10 μg L−1), and moderate chlorophyll concentration (2–9 μg L−1), albeit these conditions did not always lead to a net autotrophic balance.
Are symbiotic algae in corals in northern parts of the Persian Gulf resistant to thermal stress?
Authors: Mostafavi Pargol Ghavam , Ashrafi Mahmoud Ghayyem , Dehghani Hamed 
Published: October 2017

One of the most important factors threatening the ecosystem today is global warming resulting from human-induced climate change. Coral dominated ecosystems sensitive to such stressors are negatively affected by an increase in sea surface temperatures which can lead to the deterioration of coral reef communities. This occurs following the break-down of the symbiosis between corals and their endosymbiotic zooxanthellae which play an important role in the corals’ capacity to thrive in extreme conditions. Various Symbiodinium clades also exhibit differing resistance to such circumstances. The present study aimed to specify the zooxanthella types of coral reefs in northern parts of the Persian Gulf. For this purpose, different coral species were collected from several locations, i.e. from Larak, Farur and Hendourabi Islands. Throughout the study, partial 28S nuclear ribosomal (nr) DNA of Symbiodinium was amplified using polymerase chain reaction (PCR), and the resulting PCR products were analyzed.
Results showed that Symbiodinium clade D was the most abundant symbiont in the sampled corals. Clade C was the next most common Symbiodinium at the studied sites, with the exception of Larak Island in the Strait of Hormuz, where clade C was not found and the rarer clade A occurred. The frequency with which clade D, A and C were found was 70%, 18.3% and 11.7%, respectively. The prevalent abundance of clade D may be due to its physiology which is best adapted to the specific conditions of the Persian Gulf and its bleaching history. Hence, with global temperatures continuously on the rise, the capacity of the host-symbiont combination to mitigate the effects of global warming could result in fewer bleaching events.
Comparative analysis of fisheries restoration and public participation in Lake Victoria and Lake Tanganyika
Authors: Van der Knaap Martin 
Published: October 2017

Four decades after the initial export of Nile Perch from Lake Victoria, which reached an annual maximum harvest of 330,000 tons in 2000 (LVFO, 2009), Nile Perch resources are under pressure. With a form of co-management in place, it is not clear who is responsible for resources management. The fishers claim the Governments are responsible and the Governments say that the fish export industry is responsible. Results of six years of research led the Council of Ministers of the Lake Victoria Fisheries Organization in 2003 to endorse the recommendation to enforce drastic measures. When the measures came into force they were strictly adhered to, but with time, the authorities unwillingly relaxed them until draconian measures then had to be taken. Identical measures were adopted by the Council in 2009 and this resulted in the professional fish export associations rigidly maintaining one portion, while claiming that no scientific evidence existed for the other part.
The co-management system making use of Beach Management Units (BMU) is well developed on Lake Victoria, but has only been partly introduced to the shores of Lake Tanganyika, where certain management structures have existed for many years. This article discusses how the state of the optimum fish stocks could be regenerated, but notes that other external factors may also play roles (including climate change).
On Lake Tanganyika an industrial fishery was operational in the northern part of the lake from the mid-1970s to the mid-1990s, which gradually moved southwards with time and was outcompeted by the emerging artisanal fishery, whose effort is still increasing.
Whilst riparian Governments subscribe to international action plans, messages have to be put across to the fishing communities about regeneration of lake ecosystems.
Microbial foodweb comparison of the Laurentian Great Lakes during the summers of 2001–2004
Authors: Munawar M. , Munawar I. F. , Fitzpatrick M. 
Published: October 2017

A structural and functional assessment of the microbial foodweb of Lakes Superior, Huron, Erie and Ontario was undertaken during late summer (August) between 2001 and 2004. One lake was sampled in each year. Our analysis included microscopic enumerations of bacteria, autotrophic picoplankton, phytoplankton, heterotrophic nanoflagellates and ciliates coupled with radioisotope tracer measurements of primary productivity (14C) and bacterial growth (3H). Phytoplankton biomass was highest on average in Lake Erie (≈1.9 g m−3) and lowest in Lake Ontario (≈0.2 g m−3), whereas microbial loop biomass was highest in Lake Ontario (≈2.4 g m−3) and lowest in Lake Huron (≈0.1 g m−3). The organic carbon pool was found to be predominantly autotrophic (&gt;80%) in Lakes Superior (≈280 mg C m−3), Huron (≈195 mg C m−3) and Erie (≈660 mg C m−3) and smaller picoplankton had the highest carbon turnover rates (≈0.4–1.5 d−1). However, in Lake Ontario (≈335 mg C m−3) the carbon pool was about 75% heterotrophic and larger net plankton had the highest carbon turnover rates (≈6.8 d−1). Despite differences in trophic state, the microbial foodwebs of Lakes Superior, Huron and Erie appeared to function in a similar and efficient manner. In contrast, the microbial foodweb of Lake Ontario appeared to be unhealthy with autochthonous production being sequestered by heterotrophic nanoflagellates. More detailed work is needed to understand the foodweb linkages both within the Great Lakes and among them.
Impacts and vulnerability of inland fisheries to climate change in the Ganga River system in India
Authors: Das M. K. , Sharma A. P. , Sahu S. K. , Srivastava P. K. , Rej A. 
Published: October 2017

Climate change is evident in India as manifested by increased air temperatures, regional variation in the monsoon, frequent occurrence of droughts, and a regional increase in severe storm incidence in coastal states of India. The impacts are evident for freshwater fisheries and fishers of the River Ganga and the water bodies in its plains and deltaic areas. Analysis of time series data for 32 years from published literature and from current investigations showed a 0.99°C increase in the minimum water temperature recorded in the upper stretch of River Ganga and 0.5 to 1.4°C increases in aquaculture water on the Gangetic Plains of West Bengal. The minimum air temperature showed a 15% shift upwards during the colder months of January–February. Rainfall showed a 1% increase in the post monsoon months of September–December. The impacts were manifest in a geographic shift of warm water fish species such as Glossogobius giuris, Xenentodon cancila into the colder stretch of the River Ganga. The breeding of the Indian Major Carps (IMC) has been affected and a consequent decline in fish spawn availability in River Ganga recorded. However a positive impact on breeding in fish farm hatcheries in the Gangetic Plains was evident in the advancement and extension of the breeding period for IMC by 45–60 days. Drought in West Bengal during 2009 was evident in rainfall deficits of 29% and 27% in the districts of North 24 Parganas and Bankura, respectively, in the fish breeding months of March–September and 92% of fish spawn hatcheries were affected. These districts recorded losses on average 61% to 73% of fish spawn during 2009 compared to the previous four years. A study of the potential impact of cyclones and storms on saline water inundation using a digital elevation model generated for coastal district of South 24 Parganas indicated the potential for 3% to 11% submergence of aquaculture areas in response to 1 to 2 meter rises due to sea water incursions. The inland fisheries sector in coming years will face stiff competition for water from the industrial, municipal and agricultural sectors and climate change will compound these problems. Under such a scenario implementation of integrated water resource management involving different stake holders of fresh water would be the most effective management approach.
Institutional arrangements in fisheries of Ganges River system
Authors: Katiha Pradeep K. , Sharma Anil P. , Chandra Ganesh 
Published: October 2017

Institutional arrangements have been compared in three stretches under different management regimes, namely: (i) open access (River Ganges from Kanpur to Farakka); (ii) private contractor (River Yamuna from Yamuna Nagar to Panipat; (iii) fishermen co-operative (River Ghagra from Ghagra Barrage to Faizabad). The ownership of riverine stretches of Ganges River system is with Departments of Fisheries, Forests, Revenue and the Village Panchayats under Governments of riparian states. The ownership of more than one department in some stretches resulted in more than one lessee for fishing and conflicts among local fishers and degradation of fish stocks. The open access regime has no institutional arrangements, while for cooperative and individual/private regime, the river was leased out for 3–7 years. The lease was generally renewed for fishermen co-operatives, but for private contractors it was not certain due to bidding through open auction system and higher base price. The annual fishing efforts were at maximum and probability of irrational exploitation was high under private regime due to fishing practices adopted and limited lease period. Equity issues were better in co-operative and open access. CPUE was the highest under open access, while the costs were lowest for fisher co-operatives. Fish prices were better for fish co-operatives due to better bargaining power and collective fish disposal. The annual net returns were the maximum for fishers under open access, but net returns per kg of fish produced and output – input ratios were the highest for fishers of co-operatives. This indicated the highest working efficiency and equitable distribution of benefits under co-operative regime. The study concluded that involvement of actual fisher institutions in riverine fisheries may be encouraged for better fisheries management. A need was also felt for periodic evaluation of these institutional arrangements towards their performance and natural resources use.
Seasonal changes in the pelagic catch of two clupeid zooplanktivores in relation to the abundance of copepod zooplankton in the northern end of Lake Tanganyika
Authors: Mulimbwa N'sibula , Raeymaekers Joost A. M. , Sarvala Jouko 
Published: October 2017

Catches of clupeid fish were recorded twice a week from February 2007 to May 2008 in the northern end of Lake Tanganyika, and allocated to species (Stolothrissa tanganicae and Limnothrissa miodon) according to representative catch samples from ten artisanal lift-net fishing units. In each sample, clupeids were measured and weighed for length frequency analysis. Age was estimated from length growth curves based on otolith weight. Copepod zooplankton was sampled twice a month from February 2007 to January 2008. Peaks of copepod zooplankton were recorded in the rainy season, and there was overall a tight positive correlation between monthly rainfall and copepod biomass. The clupeids appeared in the catch at 30–50 mm length when they were two–three (S. tanganicae) or three–four months old (L. miodon). For S. tanganicae, three catch peaks were due to cohorts born when copepod food was abundant, but one catch peak was due to a cohort which originated in the dry season when copepods were scarce. Likewise, two of the L. miodon cohorts giving rise to high catches likely originated from the rainy season when food was abundant, but two cohorts apparently originated from the dry season with low food conditions. The success of several cohorts of both clupeids therefore seems to be linked to rainfall and abundance of copepods, but sometimes strong cohorts could arise even under poor food conditions. Both species were recruited in the catch far before the age of maturity, making them vulnerable to overfishing.
Estimating recreational fishing tackle loss in Mediterranean coastal areas: Potential impacts on wildlife
Authors: Lloret J. , Garrote A. , Balasch N. , Font T. 
Published: October 2017

This study evaluates the loss of recreational fishing tackle, for the first time, in a Mediterranean coastal area and discusses the potential biological impacts on fish and wildlife from exposure to lead, plastic and other toxic materials from recreational fishing. The estimation of lost fishing gear on the seabed took place over a three-year period (2010, 2011 and 2012) using divers, in two zones (4700 m2 and 5300 m2, respectively). The most abundant were lead weights (sinkers), which made up 36% of the total. Overall, the presence of a multitude of potentially harmful materials in our study area, particularly in shallow waters, demonstrates the importance of conducting studies to determine the actual impact resulting from the loss of recreational fishing tackle so that effective regulatory measures can be developed for this activity. Management concerns about these potential impacts, as well as possible solutions, are discussed.
The phytoplankton community of Lake Ontario in 2008: Structure, biodiversity and long term changes
Authors: Munawar M. , Munawar I. F. , Fitzpatrick M. , Niblock H. , Lorimer J. 
Published: October 2017

The phytoplankton community of Lake Ontario was assessed during April, July and September 2008 as part of the Cooperative Science and Monitoring Initiative (CSMI) framework. Results were also compared with historic surveys that began in 1970. A total of 320 unique species were identified during 2008, the vast majority being considered ‘rare’ or ‘less common’. The biomass was found to be, on average, 1.6 g m−3 in spring, 3.0 g m−3 in early summer and 2.4 g m−3 in late summer with rare and less common species accounting for 60–80% of the total. Analysis of the size structure of the phytoplankton community combined with size fractionated primary productivity experiments revealed that one picoplankton (&lt;2 μm) species, Chroococcus dispersus var. minor, accounted for up to half of the observed primary productivity, despite contributing 1% or less to total biomass. Our results also showed that the lake was mesotrophic during the summer of 2008 (July and September) and that trophic state has fluctuated between hyper-eutrophic and ultra-oligotrophic since monitoring began in 1970. These findings demonstrate that the Lake Ontario ecosystem is continually changing and more frequent sampling is needed. A high level of taxonomic expertise is required for even the most basic assessments of the phytoplankton community structure and improved taxonomic training and implementation of standardized techniques are necessary.
Bioaccumulation and dietary exposure of the Red-Crowned Cranes (Grus japonensis) to arsenic in Zhalong Wetland, northeastern China
Authors: Luo Jinming , Ye Yajie , Yin Xiongrui 
Published: October 2017

Arsenic concentrations in the habitat and the prey of the Red-Crowned Crane (i.e. reed rhizomes and three aquatic animal families [Perccottus glehni Dybowski, Cybister japonicus Sharp and Viviparidae]) were analyzed to examine the bioaccumulation of arsenic in Red-Crowned Cranes in northeastern China. The results indicated that arsenic concentrations in the prey of the Red-Crowned Cranes were elevated via food chain. Most of the detected arsenic contents in the sediments were below the natural background level (7.49 ppm) and ranged from 0.34 to 8.32 ppm (dry weight). The geo-accumulation indices at all sites were less than 0, which suggests the region had only background concentrations of arsenic. Three aquatic animal families were observed to contain some arsenic, with the following order of increasing concentrations: primary consumer &lt; secondary consumers. The arsenic concentrations of sediments and water animals in the buffer zone were significantly higher than those in the core area, and increased in higher trophic level animals. The highest arsenic metal concentrations were found in the livers of the Red-Crowned Cranes (in a range of 145.46 ppb to 367.78 ppb) compared with the kidneys (116.44 ppb to 257.46 ppb) and muscles (63.45 ppb to 94.26 ppb). By contrast, the feathers had the lowest concentrations, with an average of 32.25 ppb. The dietary exposure level of arsenic to the Red-Crowned Crane population in Zhalong wetland of northeastern China appeared to be below arsenic toxicity threshold concentrations.
Phytoplankton composition and microcystin concentrations in open and closed bays of Lake Victoria, Tanzania
Authors: Mbonde Athanasio S. , Sitoki Lewis , Kurmayer Rainer 
Published: October 2017

This study was carried out in order to investigate the spatial variation of algal toxin (microcystin) concentrations along the shoreline of Lake Victoria. A total of 16 nearshore stations differing in connectivity to the main lake basin were categorized as either closed bays (ratio of bay area to bay opening &lt;1) or open bays (ratio ≥1) and sampled during November and December 2009. Water samples were analyzed for total phosphorus, chlorophyll a, phytoplankton community composition and concentrations of microcystin. Open and closed bays were significantly different for phytoplankton abundance and composition: Average phytoplankton biovolume was higher for closed bays (45 mm3l−1 ± 11 SE) than open bays (5 ± 2 mm3l−1). Cyanobacterial biovolume (mainly Microcystis spp., Anabaena spp. and Planktolyngbya spp.) was also significantly higher in closed bays (82 ± 9% of total biovolume) than in open bays (44 ± 5%). In contrast, diatom biovolume was lower in closed bays (7 ± 1%) than in open bays (36 ± 6%). Microcystins were found only among sites from closed bays and concentrations ranged from 0.4 to 13 µg l−1 Microcystin-LR equivalent and coincided with high abundance of Microcystis spp. It is concluded that the level of water exchange from individual bays to the main basin is an important factor influencing eutrophication and microcystin production in nearshore habitats of Lake Victoria.