bluuebunny/crossref_metadata_2025 huggingface dataset:
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 (>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.
Community structure of macrobenthic invertebrates in the River Ganga in Bihar, India
Authors: Kumar Ram , Nesemann Hasko , Sharma Gopal , Tseng Li-Chun , Prabhakar A. K. , Roy S. P.
Published: October 2017

Benthic macroinvertebrates are reliable indicators of the environmental health of rivers as their distributions vary in response to variations in time and space and available habitats. We investigated the longitudinal and seasonal distribution of macrobenthic assemblages in different habitats (such as vegetated and unvegetated/sand, silt, rock and clay) in the River Ganga. Samples were collected in September 2010, and January, April and June 2011 at four study sites in the heterotrophic Meta-Potamon part extending from Patna through Bhagalpur covering a 249-km stretch of the river. Sampling stations were located along a gradient of macrophytic coverage in marginal water and sediment texture. A total of 69 taxa belonging to 47 families and 23 orders were identified. The data of benthic communities from all samples were subjected to non-metric multi-dimensional scaling (NMDS). NMDS of all data segregated samples on the basis of seasons. The most indicative taxon of monsoon was Culicidae followed by the Corixidae (Sigara distorta) and Micronectidae; whereas, the most indicative taxon in January was Plumatella bombayensis followed by Libellulidae. Highest abundance and species richness were recorded at Bhagalpur. Species richness and abundance were significantly higher in marginal habitats with macrophytes compared to similar habitats without vegetation. Furthermore, differences in species composition were recorded at different substrate types. The persistence of a well-structured macrobenthic community, including families of marine origin in the middle to lower reaches, indicates that the Ganga ecosystem is resilient enough to recover to its pristine ecological value.
Ecosystem health indicators in the Ganga Basin (Uttarakhand, India): Biodiversity, spatial patterns in structure and distribution of benthic diatoms, macro-invertebrates and ichthyofauna
Authors: Nautiyal Prakash , Nautiyal Rachna , Semwal Vijay Prakash , Mishra Asheesh Shivam , Verma Jyoti , Uniyal Devi Prasad , Uniyal Manisha , Singh Krishna Raj
Published: October 2017

This is the pioneering attempt to study the spatial patterns in structure of lotic ecosystems that form the Ganga River system in the Himalaya. The diversity of source (glacier-fed [GF], snow-fed [SN] and spring-fed [SF]) and stream-size (both interrelated) across the altitudinal panorama, create numerous habitats that contribute to structural diversity. The spatial patterns in richness, density and taxonomic composition and distribution of benthic diatoms are less affected by source compared with macro-invertebrates but shows strong influence on the distribution of fish fauna that are poikiliotherms, because a glacier-fed river carries ice-cold water (usually <20°C) in contrast to normal waters in spring-fed system (22°C near snowline, 32°C in foothills). The abundance patterns of biota of lower organisation grade (diatoms, macro-invertebrates) do not differ sharply even across distant river basins as they are more influenced by proximate factors; thus the sub-basins of the Alaknanda resemble more by virtue of one basin and there is notable resemblance between distant SF Bemunda (lower Ganga basin) and SF Gomti (East Rāmgangā basin) and even the farthest Yamuna and Rāmgangā. Fish are more sensitive to temperature and current velocities that are related to altitude and hence longitudinal rather than the spatial gradients in the mountains. The lotic ecosystem of Doon Valley harbour rich and diverse diatom flora, macroinvertebrate fauna and ichthyofauna. The examination of trophic, saprobic and ecological status shows that organic pollution, degradation and anthropogenic eutrophication are non-existent in the Lesser Himalayan rivers and streams, but the fragile Doon Valley is under severe anthropogenic stress. This and habitats fragmented by hydropower projects in the major rivers has threatened the iconic game fish Himalayan mahseer in the Ganga.
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.
Environmental governance dimensions and perspectives for three transboundary African lakes
Authors: Mwima Henry Kankomba
Published: October 2017

Factors considered necessary for effective environmental governance in large, transboundary lakes are presented. Institutional processes and governance structures are examined for three transboundary African lakes: Chad, Victoria and Tanganyika. Shortcomings in environmental governance for these lakes are: (i) inadequate linkages between science and policy and (ii) inadequate application of innovative, adaptive management approaches. Other shortcomings include: (i) untimely fulfillment of national and regional obligations by the riparian governments and (ii) lack of long-term sustainable financing mechanisms. Key recommendations for effective environmental governance are: linking scientific thinking and information to political decision making; investment in research and management; adoption and/or adaption of innovative management approaches; exchange of information and expertise; strategic partnerships; political commitment; long-term sustainable resource allocation; and development of mechanisms for addressing impacts of climate change and variability. Commitment to international conventions and sub-regional initiatives is also recommended for redressing environmental governance challenges for transboundary African lakes.
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.
Use of macrophytes in the bioassessment of the health of King’wal Wetland, Lake Victoria Basin, Kenya
Authors: Achieng’ A. O. , Raburu P. O. , Okinyi L. , Wanjala S.
Published: October 2017

King’wal wetland, at the upper catchment of Lake Victoria, is undergoing anthropogenic disturbances which degrade its health. In this study, the wetland's health was assessed using water quality parameters and wetland macrophytes, sampled monthly at five stations from November 2010 to February 2011, and the health was evaluated using the Plant Index of Biotic Integrity. Mean dissolved oxygen and biological oxygen demand were significantly different among the stations (F = 10.67, p = 0.000 and F = 10.12, p = 0.000, respectively). Correlation matrix in principle component analysis for stations and the two mean measurements were negative in stations 3, 4 and 5 with component 1 at 62.3% variance and component 2 at 33.9% variance, and positive for mean TN and TP in the same stations indicating a nutrient rich environment. Anthropogenic activities including agriculture, livestock grazing, human settlement and urbanization were the main threats to the health of King’wal wetland. The index scores at the three transect delineated areas with minimum disturbance (ST 3) and those that were highly disturbed (ST 5). However, the entire wetland can be classified as being moderate in health. Wise use and regular monitoring of the wetland is recommended to ensure maintenance of its health.
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 (<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.
Seasonal variation of chlorophyll a in the South China Sea from 1997–2010
Authors: Liu Fenfen , Chen Chuqun
Published: October 2017

This study aims to document the seasonal cycle of chlorophyll a interannual variability and to determine the dynamic framework for understanding the mechanisms that produce it. We investigated the variation in sea surface chlorophyll a concentration from autumn 1997 to summer 2010 in the South China Sea using the Sea-Viewing Wide Field-of-View Sensor products. Using the Season-Reliant Empirical Orthogonal Function method, we revealed the interannual and seasonal variations and their dependency on climate variability. The time coefficient of the first mode shows a sudden drop in 2007. Corresponding season-reliant empirical orthogonal function (spatial pattern) is the largest in the southern centre in the autumn, which can be explained by a large increase in chlorophyll a concentration during which Typhoon Hagibis passed through. The second mode reflected an anomalous event of low phytoplankton biomass in the western center of the sea during the summer of 1998 and 2010 due to an El Niño event. Time coefficient is negatively related with the Multivariate El Niño–Southern Oscillation Index. The third mode revealed an interannual variability of chlorophyll a in the region to the northwest of Luzon Islands, which appeared from autumn to the next spring. To better understand the chlorophyll a variation off the South Vietnam coast, we analyzed the summer chlorophyll a variability in this local region solely using the Empirical Orthogonal Function method.
Atlantic Salmon and Brown Trout in Lake Vänern: A proposal for a co-management system
Authors: Bergman Eva , Norrgård Johnny R. , Piccolo John J. , Gustafsson Pär , Nilsson Fredrik , Hart Paul J. B.
Published: October 2017

Co-management is of increasing interest for fisheries management. We explore possibilities for, and barriers to, developing a co-management system, using threatened populations of landlocked Atlantic Salmon and Brown Trout as examples. Good management of natural resources requires not only knowledge about the resource, but also suitable tools to collect information and make decisions. In large ecosystems this can be difficult because many actors are involved, and various societal borders and traditions become barriers. Vänern is the largest lake in the European Union and it holds several distinct populations of large-bodied landlocked Atlantic Salmon and Brown Trout. The lake is used for commercial, subsistence, and sport fishing as well as for other recreational activities; in Klarälven, the largest river entering Vänern, sport fishing is popular. These salmonid populations were at critically low levels during the 1960s, but a stocking program since then has maintained the fishery. At least one wild stock appears to be recovering since being protected in 1993. Ecosystem users all have different needs: in the lake, sport fishermen say that catches of hatchery fish have declined, and commercial fishermen have focused on other species. In the river, wild salmon may be recovering: sport fishing is popular and an ongoing project investigates the possibilities for salmon to be able to circumvent hydro-electrical plants and reach historical Norwegian spawning areas. Not only do we lack information about the salmonids’ different life stages, we also lack a suitable socio-political organization to find sustainable solutions to the different needs of diverse user groups. We argue that a co-management system that enfranchises user groups in the Vänern-Klarälven ecosystem will improve sustainable management of wild and hatchery fish.
A test of sampling methods for fishes in the littoral zone of Lake Vänern, Sweden
Authors: Sandström Alfred , Bergquist Björn , Ragnarsson-Stabo Henrik , Andersson Magnus
Published: October 2017

Shallow, vegetated habitats play an important role as spawning and nursery areas for several species of fish. Such habitats are often laborious to monitor with conventional sampling methods. We evaluated two quantitative methods for sampling of young fishes in shallow habitats; point abundance with electrofishing and low-impact pressure wave sampling using small underwater detonations. The study was conducted in the littoral zone of an archipelago area in Lake Vänern, Sweden. Both methods rendered quantitative estimates on the most common fish species. However, underwater detonations yielded more species and lower variation among samples. These differences are likely due to the larger sample area of detonations. Species distribution and juvenile fish density estimates and size-structure were compared with results from multi-mesh gill nets. The dominant fish species in the gill net program were recorded with both active methods although the relative composition differed, mainly as a consequence of differences in species and size selectivity. Detonations provided additional, small-bodied, species that were not recorded in the gill net program. Quantitative methods can provide relevant information for identifying essential fish habitats, understanding ecosystem dynamics and providing a baseline for assessing long-term changes (e.g. due to climate change or new water level regimes) in Lake Vänern.
Progress towards the implementation of the European Water Framework Directive (2000–2012)
Authors: Phillips Geoff
Published: October 2017

The European Water Framework Directive, which came into force in 2000, introduced a system of river basin management which required member states to develop a range of new biological assessment systems to determine the status of Europe’s surface waters. Member states were free to use existing methods or to develop new ones, which resulted in a large number of methods being used across Europe. To ensure the comparability of the resulting assessments, these states were required to compare their methods to demonstrate that the boundary criteria they established represented similar levels of ecological change. Although it is desirable to align status class boundaries to significant changes of ecological status, so that the resulting classifications can be linked to ecosystem function, many methods simply divide status into five equal classes along a pressure gradient. An exception was the approach used for lakes, where a greater understanding of the impacts of eutrophication has been established. Here, boundaries were derived from the likelihood of undesirable disturbances caused by the secondary impacts of eutrophication. The Water Framework Directive has now been in force for twelve years, new monitoring systems have been developed and management plans have been adopted. While it is unlikely that the aim of achieving good ecological status can be achieved in the majority of surface waters by 2015, the default target established by the directive, good progress is being made and Europe is on the path to establishing a sustainable future for its water environment.
Aquatic ecosystems across boundaries: Significance of international agreements and cooperation
Authors: Dave Göran , Munawar Mohiuddin
Published: October 2017

Historically, international environmental agreements on shared transboundary waters have dealt with exploitation of natural resources like oil, minerals, forests, fisheries, shipping and trade. Presently the focus is on environmental issues relevant to conservation, restoration, protection, sustainability over-fishing, pollution, invasive species and climate change. Global assessment indicates a lack of international agreements between multiple users. A brief review of major conventions and agreements is offered with emphasis on the Great Lakes Water Quality Agreement on the North American Great Lakes and the European Water Framework Directive, since they appear to be ecologically sound and predominantly ecosystem-based. This article exemplifies the history behind these agreements with examples of environmental threats and consequences (eutrophication, pollution, invasive species and loss of biodiversity). It is concluded that such ecosystem-based agreements are essential for all large aquatic ecosystems shared by multiple users or countries for holistic and integrated management of aquatic resources.
Analysis of sediments and suspended material in lake ecosystems using near-infrared spectroscopy: A review
Authors: Malley D. F. , Williams P.
Published: October 2017

Lake sediments serve as archives that reflect biological and chemical conditions of lakes. Carbon, nitrogen and phosphorus are determined in sediments and in suspended material in lakes, termed seston, for a number of purposes. These include: assessment of sediment quality, identification of the trophic level of lakes, and study of contaminants. The use of near-infrared spectroscopy provides a rapid and cost-effective alternative for routine analysis of large numbers of samples. Calibration equations developed from spectral data and the results of conventional chemical analysis on an initial set of representative samples are used to predict constituents in future unknown samples of the same type. In sediment samples and seston, carbon, nitrogen and phosphorus were generally predicted very successfully by near-infrared spectroscopy. The best samples for analyzing sediment quality are generally those from the deepest part of a lake. Spatial variability in sediment quality of a lake was successfully explored by this method, suggesting that near-infrared spectroscopy is a potential complementary tool to standard methods for analyzing and characterizing sediments.
Health of the Salish Sea as measured using transboundary ecosystem indicators
Authors: Wong Cecilia , Rylko Michael
Published: October 2017

The Salish Sea ecosystem is a transboundary area of ecological, social, and economic significance shared by Canada and the United States. Accordingly, the United States Environmental Protection Agency and Environment Canada have committed to cross-border collaboration on Salish Sea issues. The transboundary ecosystem indicators project was established to support knowledge sharing and to identify common priorities for action. Mixed trends were observed among ecosystem indicators, reflecting the complexity of the system. Improvements were demonstrated among indicators of air quality, freshwater quality, and toxics in the food web. Declining trends were observed among indicators of marine water quality, marine species at risk, Chinook Salmon, and summer stream flow. Variable or neutral trends were observed among indicators of southern resident Killer Whale abundance, access to Shellfish beaches, and access to swimming beaches. While the indicators represent separate ecosystem components, including air, water, species condition, and human wellbeing, these indicators are interrelated through biophysical cycles. Methods and results of tracking transboundary ecosystem indicators are presented to facilitate the identification of primary drivers and pressures of observed trends, and responses that have had positive results on a site specific basis.
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 < 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 <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.
Invasion history and vector dynamics in coastal marine ecosystems: A North American perspective
Authors: Ruiz Gregory M. , Fofonoff Paul W. , Steves Brian P. , Carlton James T.
Published: October 2017

The known extent of biological invasions exhibits strong variation with respect to space, time, taxonomic group, and vector. Using a synthesis of nonindigenous species (NIS) occurrences in North America, we characterized the invasion history for coastal marine ecosystems by invertebrates and algae through 2010, to evaluate variation and existing patterns at a continental scale. This study updates a previous analysis of invasions for the same taxonomic groups in North America, providing a first assessment of changes in the last 11 year period (2000–2010). Overall, we documented 450 marine and estuarine NIS that are considered to have established populations in tidal waters of North America, representing a 51% increase in NIS richness compared to the earlier analysis. Of the 152 species added, 71 species (47%) have first documented records since the year 1999, and 81 species (53%) were additions attributed to earlier time periods due to recent reports and further analysis. Across all time periods, taxonomic groups with the largest contribution were Crustaceans (112 species) and Molluscs (80 species), together providing 43% of the total species richness for North America. Species richness was unevenly distributed among coasts, with most documented on the Pacific Coast (310 species) and fewer on the Atlantic Coast (189 species) and Gulf Coast (88 species). Commercial ships have contributed between (a) 44–78% of the initial (primary) invasions of all nonindigenous species to North America and (b) 52–82% of NIS in the last 30-year time interval, being driven by transfers associated with ballast water and hull biofouling. Importantly, invasion dynamics are a shifting landscape, where the past may not predict the future, especially with emerging trade patterns and global to local environmental changes. Thus, effective management to reduce future invasions requires a dynamic and multi-vector approach, instead of single vector strategies based on past history alone.
Fish diversity in Kyrgyzstan: Species composition, fisheries and management problems
Authors: Kustareva L. A. , Naseka A. M.
Published: October 2017

The territory of Kyrgyz Republic (or Kyrgyzstan) is interesting from a zoogeographical point of view, as it straddles several major ecoregions: Balkhash Lake basin, Chu River drainage, Lake Issyk-Kul basin, Talas-Ters drainage, Upper Syr Darya system, Upper Amu Darya system and Tarim basin. Species composition of fish faunas of all ecoregions are discussed and endemic species and subspecies listed. The degree of endemism is notable, reaching 55 and 70% in the Talas River and Issyk-Kul Lake ecoregions, respectively. Some aspects of human impact on native fish populations are analysed, including the introduction and establishment of exotic species that dominate some lakes and reservoirs, fisheries and aquaculture. A review of fishery resources management underlines the need to formulate a compromise strategy for the conservation of unique native fish communities, and the development and management of capture fisheries, based on both native and exotic species, and aquaculture in Kyrgyzstan.
The fishes and fishery in Lake Baikal
Authors: Matveyev A. N. , Samusenok V. P.
Published: October 2017

This article reviews the fish fauna of Lake Baikal, the world's deepest and largest lake in volume. The nucleus of the fish fauna of Lake Baikal is a unique complex of endemic cottoid fishes (56% of the total number of species and 41% of the total number of genera) and endemic species and subspecies of the coregonid and thymallid families. Abundance and composition of the fish fauna have changed during the 20th Century in each of the three main parts of the lake: north, central and south. Historical and present environmental conditions, such as main habitats, water quality and anthropogenic impacts, are discussed. Key objectives of fishery management on Lake Baikal include: (i) protection of fishes, especially commercial species, during periods of preparation for spawning, on spawning runs and in spawning areas; (ii) progressive restriction of the industrial fisheries and rapid expansion of sports and recreational fisheries; (iii) reallocation of priorities in the artificial breeding of fishes to restore the natural population structure of Omul and to restore the abundance of other valuable species that are important for sport fishing; (iv) prevention of the introduction into the Baikal basin of any new non-indigenous fish species; (v) conservation of habitats used by different ecological groups of fishes.
Dagestan fisheries in the Western Caspian Sea: Current status, factors of impact and recommendations to sustainable management
Authors: Abdusamadov A. S. , Belyaeva H. S.
Published: October 2017

This article reviews the status of fisheries in the western parts of the North and Middle Caspian Sea in the territory of Dagestan Republic, the Russian Federation. Commercial fish stocks are greatly influenced by changes in the Caspian environment induced by natural (sea level fluctuations, water advection, seabed seismicity) and anthropogenic (regulation of major rivers, pollution, invasive species, etc.) factors, as well as fishery management. Fisheries development in Dagestan is reviewed by: (1) summarizing data on the biological and eco-geographical context of biological productivity; (2) evaluating the current status of stocks of the major commercial fish species in this region and assessing the prospects for their commercial use; (3) analyzing the responses of aquatic biological resources to natural and anthropogenic impacts. A number of recommendations are suggested for establishing sustainable fisheries management in the Western Caspian Region.
Review of environmental conditions in the water level fluctuation zone: Perspectives on riparian vegetation engineering in the Three Gorges Reservoir
Authors: Yang Fan , Wang Yong , Chan Zhulong
Published: October 2017

We reviewed the current ecological and environmental conditions within the water level fluctuation zone of the Three Gorges Reservoir. This zone encountered several eco-environmental problems, including the loss of biodiversity, soil erosion, challenges for land use, non-point-source pollution, nutrient accumulation, and heavy metal pollution, which seriously affected the ecological integrity and water quality of the Three Gorges Reservoir. Our review revealed that vegetation restoration of the water level fluctuation zone may be an ideal system response to cope with its eco-environmental problems. Further, riparian vegetation had potential in reducing soil erosion, preventing nutrient accumulation, and adsorbing heavy metal pollutants in this fluctuation zone. We also described remedial riparian vegetation engineering in the Three Gorges Reservoir fluctuation zone: both past and potential. Vegetation engineering will be critical for improving the eco-environmental conditions in the fluctuation zone, and for maintaining ecological integrity of the Reservoir. Recommendations for on-going remedial actions were provided.
Risk assessment: Cornerstone of an aquatic invasive species program
Authors: Mandrak Nicholas E. , Cudmore Becky
Published: October 2017

Understanding the biological and socio-economic risks associated with existing and potential aquatic invasive species is essential for an aquatic invasive species program to be successful. Effective programs are based on risk analyses, in which risk assessment informs risk management and both are communicated to resource managers and the public. Risk assessments provide valuable information that can be applied to many areas of an aquatic invasive species program. Based on biological and socio-economic risk assessments, appropriate risk management actions related to prevention, early detection and rapid response, and control can be undertaken. In particular, biological risk assessments inform both socio-economic risk assessment and subsequent preventative, monitoring, and control management actions. The uncertainty and knowledge gaps identified in risk assessments help identify and prioritize future research. Risk assessments are used to identify the riskiest aquatic invasive species and pathways and can be used to identify effective management, policy, and legislative actions to minimize risk. This, in turn, allows for the optimal allocation of limited resources to combat aquatic invasive species; therefore, risk assessment should be considered the cornerstone of a successful aquatic invasive species program. This article describes the risk analysis of aquatic invasive species, with emphasis on biological risk assessment and how they can be managed using marine and freshwater examples, with particular emphasis on the risk assessment of Bigheaded Carps in North America.
Primary nitrite maximum in the euphotic layer near the Xisha Islands, South China Sea
Authors: Wu Mei-Lin , Liu Qin-Yan , Dong Jun-De , Wang You-Shao , Wang Dong-Xiao
Published: October 2017

A subsurface nitrite maximum was observed along one transection near the Xisha Islands in the South China Sea in early September 2009. Possible causes were examined using in situ observed data and remote sensing data. A cold eddy was identified near the Xisha Islands during the periods of study. The Xisha Islands' water receives copious supplies of nutrients through cold eddies. Accumulation of nitrite about 50 m deep reaches 0.49 μmol l−1, and forms and maintains the primary nitrite maximum. The relationship between NO2− and Chl-a is very significant (R2 = 0.5829, p-value(statistical significance) = 0.00). Nitrification processes would result in apparent oxygen utilization (AOU) ranging from 0.22 to 35.88 μM, around 24.60% of the total biological oxygen demand in the water column of under-saturation of dissolved oxygen. This value is very close to the Redfield stoichiometry (32/138 = 23%) of total oxygen consumption associated with organic matter diagenesis. These results may support the hypothesis that phytoplankton and the nitrification process have an important influence on the PNM or 260 maintenance in the euphotic layer. Our results indicate that physical conditions and biological activities near the Xisha Islands play a significant role in regulating biogeochemistry.
Can a copper sulphate pulse below toxic threshold change plankton communities?
Authors: Del Arco Ana I. , Jiménez-Gómez Francisco , Guerrero Francisco , Parra Gema
Published: October 2017

More field relevant ecological assessments, apart from single species tests using standard species, are needed to better predict agrochemical effects at higher ecosystems levels. Therefore, an experiment using a non-target aquatic community was used to test the hypothesis of the negative effect of a single pulse of copper sulfate on plankton abundance, structure, richness and diversity endpoints. Microcosms (20 l volume) were established during 21 days of experimentation, using six replicates for controls and with two concentrations of copper sulfate (High treatment, H: 20 µg Cu l−1; and Low treatment, L: 2 µg Cu l−1), both within the copper legal threshold following the Water Framework Directive (2000). The general lineal model found significant differences at the phytoplankton abundance endpoint at the end of the experiment, with an increase of phytoplankton abundance in L treatments dominated by the smaller cell size class. The principal response curve on zooplankton data, despite being insignificant, pointed out some dissimilarities in abundance and structure between treatments and controls: treatments showed lower abundances and were richer in cladocerans and copepods than the control microcosm where rotifers and nauplii were dominant. This indicated that trends change in community structure due to the effects of copper sulfate, and that even if the copper concentrations under study were within legal limits, they showed potential to induce changes in planktonic communities.