bluuebunny/crossref_metadata_2025 huggingface dataset:
Water quality remediation in a heavily polluted tidal river in Guangzhou, South China
Authors: Sheng Yanqing , Chen Fanzhong , Sheng Guoying , Fu Jiamo
Published: October 2017

A field-scale experiment was performed to remediate a heavily polluted river located in the urban area of Guangzhou, China using biological and chemical techniques combined with engineering processes. Before comprehensive remediation was undertaken, several small-scale experiments to test river-water remediation techniques were successfully performed. After comprehensive remediation, the average reduction rates of chemical oxygen demand and biochemical oxygen demand and removal rates of other pollutants were all above 70 percent. Furthermore, the unpleasant odor emanating from the polluted river was also greatly reduced. The field-scale experiment thus indicated the feasibility and validity of the method applied to remediate this heavily polluted river; this method can therefore be applied to remediate other heavily polluted rivers in the Guangzhou urban area and elsewhere.
Fluctuations of satellite-derived chlorophyll concentrations and optical indices at the Southern Yellow Sea
Authors: Xing Qianguo , Loisel Hubert , Schmitt François G. , Dessailly David , Hao Yanju , Han Qiuying , Shi Ping
Published: October 2017

Time series of chlorophyll-a concentration (chl a), backscattering coefficient at 490 nm (bbp(490)) and spectral slope of bbp (γ) derived from satellite imagery of ocean color were used to study the aquatic ecosystem of the Southern Yellow Sea during the time period of 1997–2007. Our study indicated that chl a increased in offshore waters by 0.02 mg m−3 y −1 (p < 0.05), in contrast to a decline observed in the middle and low-latitude global waters. bbp(490), a proxy of total suspended particulate matter concentration did not have any significant trend, while γ, a proxy of the relative proportion of small-sized and larger particles in the surface ocean, decreased significantly. Annual spring phytoplankton blooms occurred in nearshore and offshore waters of the central Southern Yellow Sea; while autumn blooms only occurred in nearshore waters.
Statistical analysis of accumulation patterns of heavy metals in biota from the Pearl River Estuary, South China
Authors: Zeng Yanyi , Huang Xiaoping , Ye Feng , Tian Lei
Published: October 2017

The object of this study was to identify the accumulation patterns of Cu, Pb, Zn and Cd in different consumers living in the Pearl River Estuary. Concentrations of metals in water, sediments and tissues of demersal fish, crustaceans and molluscs were determined. Cluster analysis and principal component analysis were used to evaluate accumulation patterns of these four metals among species. Fish species were clustered as a group which was characterized by low accumulation of Cu, Zn and Cd. By contrast, crustaceans and molluscs were clustered to another group which was characterized by high accumulation of Cu, Zn and Cd. However, no significant difference of Pb accumulation between the two groups was identified. In addition, the concentrations of the four metals in fish were strongly correlated with metal concentrations in sediments, indicating that the sediment was the source of heavy metals in fish. Moreover, the accumulation of a heavy metal in fish was correlated with the same metal element and other heavy metals in the sediments. This may demonstrate a tendency of cross-acclimation in fish to different metals within the special habitat from the Pearl River Estuary. Dietary attention should be paid to the high concentrations of Pb in fish and crustaceans.
Levels, spatial distribution and sources of selected antibiotics in the East River (Dongjiang), South China
Authors: Zhang Ruijie , Zhang Gan , Tang Jianhui , Xu Weihai , Li Jun , Liu Xiang , Zou Yongde , Chen Xiaoxiang , Li Xiangdong
Published: October 2017

Eleven selected antibiotics in the East River, South China, were measured using high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-EI-MS-MS). Erythromycin, roxitromycin, azithromycin, clarithromycin, sulfadimidine, sulfamethoxazole, sulfadiazine and trimethoprim were detected with frequencies of more than 75%, and average concentrations ranging from 0.9 to 67.4 ng l−1. The other three compounds’ (sulfathiazole, sulfacetamide and spiramycin) concentrations were below detection limits. In general, the concentrations of sulfonamides and trimethoprim were higher than those of macrolides. The concentrations of macrolides showed a spatial distribution pattern of delta > lower reach > middle reach (or urban area > agriculture area), while sulfonamides and trimethoprim did not have a significant spatial pattern. Principal component analysis and comparison with wastewater were further used to explore source information of the antibiotics. The results suggested that macrolides in the East River were mainly associated with domestic sewage, while sulfonamides and trimethoprim may be more related to agriculture wastewater, especially livestock industrial wastewater. It is suggested that to ensure/improve the drinking water quality in the region, a better pollution control of livestock industry in the lower and middle reaches is of critical importance.
Organotin residues in Rock Shell, Thais clavigera, and their sources in Kagoshima Bay, Japan
Authors: Koyama Jiro , Takenouchi Aya , Nigaya Sayoko , Kokushi Emiko , Uno Seiichi
Published: October 2017

Organotin compounds (OTCs) such as tributyltin (TBT) and triphenyltin (TPT), which are contaminating many coastal areas, are known to induce imposex in female gastropods. Hence, imposex induction in the Rock Shell Thais clavigera from 2003 to 2010 and OTC concentrations in the water, sediments, T. clavigera and in their prey were investigated from 2004 to 2006 at Iso (reference site) and Akobaru (polluted site) in Kagoshima Bay, Japan. Almost all female Rock Shells at Akobaru had imposex induction, but none at Iso. Higher concentrations of TBT and TPT in sediments (123 ng g-1 dry weight for TBT and 6.4 ng g−1 for TPT), Rock Shell (97 ∼ 182 ng g−1 for TBT and less than detection limit for TPT) and their prey (2.7 ∼ 289 ng g−1 for TBT and 1.8 ∼ 4.1 ng g−1 for TPT) were detected at Akobaru as compared to Iso. However, TBT and TPT in the water at Akobaru were less than 3.6 ng l−1 and less than 0.2 ng l−1, respectively. These results suggested that prey organisms were the main sources of organotin compounds in Rock Shells, while the source of these compounds in prey organisms was possibly the sediments or suspended particles.
PCDD/F contamination of the Venice Lagoon: A history of industrial activities and past management choices
Authors: Bellucci Luca Giorgio , Mugnai Cristian , Giuliani Silvia , Romano Stefania , Albertazzi Sonia , Frignani Mauro
Published: October 2017

The history of the Venice Lagoon contamination is presented here, based on sediment records and on information about industrial activities and past management choices. We used polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as tracers since the relative abundance of their congeners can help in locating their sources. The most important PCDD/F source to the canals of the first industrial area (built in the 1920s) can be ascribed to processes involving pyrite to obtain sulfuric acid and recovery of copper and other metals. Indeed, homologue profiles and documents show that the PCDD/Fs contamination is mainly related to the use and disposal of both these industrial wastes and materials dredged from the most contaminated canals. In particular, these latter constitute the ground under the second industrial area (built after World War II). Furthermore, hazardous materials were stored until 1992 in an islet exposed to erosion, whereas tracts of industrial canal banks eroded until 2000. Similar situations are frequent in transition and coastal areas worldwide.
Relinkage of the Mfolozi River to the St. Lucia estuarine system – urgent imperative for the long-term management of a Ramsar and World Heritage Site
Authors: Whitfield Alan K. , Bate Guy C. , Forbes Ticky , Taylor Ricky H.
Published: October 2017

The St. Lucia Estuary was separated from the Mfolozi River in the early 1950s following canalisation of the Mfolozi floodplain swamp that resulted in the deposition of large amounts of sediment in the estuary. A separate Mfolozi River mouth has been maintained artificially since then and the deleterious consequences in terms of freshwater supply to the St. Lucia system are now becoming fully apparent, especially following the latest drought. Fish and penaeid prawn stocks in Lake St. Lucia have collapsed and the loss of this major southern African estuarine nursery area for these faunal components has had a significant impact on fish and prawn catches in adjacent coastal waters. It is therefore imperative that a re-linkage of the Mfolozi River to the St. Lucia system occurs so that the health and conservation status of the St. Lucia ecosystem, which is a Ramsar and World Heritage Site, can be assured. This review of the major findings presented at a recent scientific workshop explores the need for, and consequences of, a reconnection between the Mfolozi River and St. Lucia Estuary and makes some preliminary suggestions towards the achievement of that goal. Foremost amongst these proposals is to use the subsiding Mfolozi floodplain as a sink for excess sediment carried by the Mfolozi River before it enters the St. Lucia system, as well as various strategies in terms of reconnection options.
Temporal and spatial variability of benthic macrofauna communities in the Yangtze River estuary and adjacent area
Authors: Shou Lu , Zeng Jiangning , Liao Yibo , Xu Ting , Gao Aigen , Chen Ziqiang , Chen Quanzhen , Yang Jiaxin
Published: October 2017

Four cruise surveys were carried out in summer, winter, spring, and autumn from 2006 to 2007 to evaluate the seasonal distribution of macrobenthos in the Yangtze River estuary and its adjacent waters. A total of 59 sites were sampled and divided into three areas (estuary, inshore, and offshore areas). In all, 335 taxa were collected with polychaetes and mollusks being the dominant groups. Two-way ANOVA revealed significant differences among the numbers of species, densities, and biomasses in the areas. However, several differences were found among seasons. SIMPER analysis showed that the dominant species of macrobenthos varied in different areas, and the inshore area was the most complex of the three. The abundance/biomass comparison (ABC) curve of macrobenthos in the inshore area showed apparent rises and falls, which are characteristic of disturbance to macrobenthos. Canonical correspondence analysis showed that echinoids were closely related to the presence of silicates and temperature, whereas polychaetes were closely related to depth and temperature.
The science of ecosystem-based management on a global scale: The Laurentian Great Lakes, Lake Ontario, and the Bay of Quinte as a nested case study
Authors: Minns C. K.
Published: October 2017

Lake ecosystems are our sentinels of environmental change and their effective management is one of our key planetary challenges in the 21st century. The evolution of ecosystem science as a basis for management is reviewed using the nested set of the Laurentian Great Lakes, Lake Ontario, and the Bay of Quinte as a primary focus. Other great lakes of the world, many of which are in Canada, provide a secondary focus. Ecosystem science has a long history in the Laurentian Great Lakes with developments driven in large part by the Great Lakes Water Quality Agreement, Lake-Wide Management Plans, and Remedial Action Plans for Areas of Concern. By comparison most other large Canadian lakes have received little attention as is the case with many of the world's great lakes. The substantial arsenal of tools and knowledge accumulated in the Great Lakes can serve as a model for other lake systems. As the range of ecosystem management problems has continued to grow, the motivating theme has shifted from restoration through rehabilitation to adaptation. The main challenge is to coalesce the many stresses we previously have sought to manage singly: land use, population growth, habitat degradation, resource exploitation, invasive species, pollutant and contaminant loadings, and, finally, climate change. Essential features of effective ecosystem-based management are: a whole system view, active adaptive management, acceptance of science-based evidence, and shared goals with common objectives. The last two may prove the greatest hurdle as society becomes ever more divided and fractious given the global onslaught of environmental and societal challenges. The Great Lakes experience shows there is hope.
May we eat biodiversity? How to solve the impasse of conservation and exploitation of biodiversity and fishery resources
Authors: Van der Knaap Martin
Published: October 2017

Some of the characteristics of the African Great Lakes are the numerous species of fish, crustaceans, mollusks, plankton, and other phyla, most of them endemic. The usual sources of perturbation when speaking about Great Lakes also have their impacts on the African Great Lakes, such as overfishing, dumping of untreated sewage, pebble and sand mining, agricultural run-off and other threats. Should this biodiversity be protected in times of sheer poverty of the riparian populations? Should it be exposed to exploitation for food security? What are the values of these endemic species in economic terms? This article reviews the impacts on biodiversity by human-induced factors like exotic fish introductions and the invasive water hyacinth, but also by indirect factors like climate change. Lake Victoria has a long history of fish introductions and invasive weeds, but on Lake Tanganyika the original species composition of many taxa can still be preserved and protected, at a cost. The Great Lakes surrounding these countries, by means of conventions and regional management bodies, sought to protect the environments and called for international collaboration to improve management of the natural resources, both terrestrial and aquatic. The way forward will be to involve local fishing communities in nature conservation and management, but there are many communities and many fishermen. How to reach them in areas where there is no municipal electricity supply, no portable phone network, nor internet facilities. In the 21st century, around the African Great Lakes the keyword is survival, not only of biodiversity, but also of the inhabitants of their basins.
Application and transferability of Great Lakes coastal wetland indices of biotic integrity to high quality inland lakes of Beaver Island in northern Lake Michigan
Authors: Calabro Eric J. , Murry Brent A. , Woolnough Daelyn A. , Uzarski Donald G.
Published: October 2017

Biological indicators or indices of biotic integrity (IBI) have been developed for land management and regulatory agencies to categorize the condition of a given ecosystem. IBIs are more widely used in lotic systems and those that can be used over wide geographic regions or multiple systems are deemed most valuable. Lacustrine wetlands have intrinsic complexity and multidimensionality making them very difficult to classify. This, in turn, greatly affects the transferability of indices created for explicit regions and wetland types. Similarly, due to scarcity, relatively pristine reference conditions are seldom included in IBI calibration and represent a critical end of the disturbance continuum.

The robustness and transferability of macroinvertebrate and fish IBIs created for fringing lacustrine and drowned river mouth wetlands of the Great Lakes for use in wetlands occurring in inland-lakes on islands within the Great Lakes were tested. Islands within the Laurentian Great Lakes contain unique and critical habitats that have received little attention, but also require specialized tools for monitoring and management. Inland-lake wetlands of Beaver Island, Lake Michigan, were ranked a priori along a disturbance gradient based on adjacent land use/cover. Transferability of the pre-existing Great Lakes IBIs was determined by correlating the site-specific IBI rank with the site-specific disturbance ranks. Results indicated that the IBIs were not directly transferable and may require substantial modification.
Landscape indicators of stream water quality in central Appalachia (USA): Land use/land cover or land surface condition?
Authors: McMichael Christine E. , Smith David P. , Johnson Robert C.
Published: October 2017

Relationships between land use/cover (LUC) and stream water quality have been well-documented in many environments and at a range of spatial scales. From these analyses, reduced in-stream biological integrity and habitat quality are commonly associated with increasing amounts of anthropogenic LUC. However, very few studies have examined the influence of landscape condition, relative to studies using LUC, on water quality parameters. Landscape condition indices use remote sensing-based data to quantify biophysical land surface condition.

The primary objective of this study was to assess the relationships between LUC class proportions and indices of land surface condition (LSC) and macroinvertebrate-based water quality metrics. These relationships were examined at three spatial scales (reach, stream network, and catchment). Strong correlations were observed between both LUC class proportions and LSC indices with macroinvertebrate-based metrics, although there was almost twice the number of significant correlations for LUC as compared with LSC. Similar to previous research, relationships between landscape variables and macroinvertebrate metrics were not consistent across spatial scales. Overall, results suggest that LUC class proportions are better indicators of water quality conditions in the study area. Future work will expand this analysis and include additional water quality parameters and landscape variables with the goals of deepening the understanding of landscape impacts on stream water quality and providing resource managers with valuable information that will to help guide planning and assessment activities.
Spatial distribution of pelagic fish larvae in the northern main basin of Lake Huron
Authors: Roseman Edward F. , O’Brien Timothy P.
Published: October 2017

Larval fish occurrence in inshore and offshore zones in the northern main basin of Lake Huron was assessed during 2007 as part of a larger ecological examination of Lake Huron foodwebs and habitats. Day and night collections using neuston and conical nets at inshore (1.5–15 m depths) and offshore (37 and 91 m depths) locations at De Tour and Hammond Bay to assess the abundance, phenology, and spatial distribution of pelagic ichthyoplankton during spring and early summer were made. In general, densities of larval fishes were higher at De Tour than Hammond Bay during daytime neuston net collections, with the exception of Longnose Sucker, which were only collected at Hammond Bay. Lake Whitefish, Burbot, and Rainbow Smelt dominated inshore catches in early spring with Cisco, Deepwater Sculpin, Emerald Shiner, Bloater, Slimy Sculpin, Ninespine Stickleback, and Yellow Perch larvae also collected.

Nighttime nearshore and offshore sampling revealed that Rainbow Smelt and Burbot larvae were present in relatively high abundances compared to inshore densities. Concentrations of larvae of deepwater demersal fishes such as Lake Whitefish and Deepwater Sculpin suggest that inshore zones in northern Lake Huron are important nursery habitats emphasizing a critical production and recruitment linkage between inshore and deepwater zones.
Management of land-based sources of marine pollution
Authors: Al-Muzaini Saleh
Published: October 2017

The coastal waters of Kuwait Bay have been extensively used for the disposal of domestic wastewater, increasing the level of pollution. Recent studies indicated that the amount of waste discharged into Kuwait Bay is expected to grow further, from raw sewage, illegal disposal of partially treated sewage, and industrial waste. These sources play significant roles in heavy metal, hydrocarbon, and fecal coliform bacteria inputs to Kuwait's coastal waters, which impact the marine environment and lower water quality. This article introduces information relating to pollution levels in Kuwait's marine environment from land-based sources, and compares the level of pollutants in marine waters with water quality standards. This study also recommends an environmental waste management procedure to control waste discharges to the marine environment with a view to future aspects of sustainable development.
Ichthyofaunal diversity, assemblage structure and seasonal dynamics in the freshwater tidal stretch of Hooghly estuary along the Gangetic delta
Authors: Roshith C. M. , Sharma A. P. , Manna R. K. , Satpathy B. B. , Bhaumik U.
Published: October 2017

The tidal freshwater areas of estuaries have received little attention in ecological research although they are often heavily stressed by environmental impacts. These critical habitats contribute significantly to the biodiversity of the entire estuarine system. The present study aims to describe the fish diversity, assemblage structure and seasonal dynamics through data collected by intensive sampling of the tidal freshwater stretch of the Hooghly estuary (June 2010 to June 2012), the largest estuary in India formed in the Gangetic delta. The tidal freshwater zone of Hooghly has gained importance due to ecological changes during the post-Farakka period since this zone covers 74% of the total estuarine stretch. During the study, a total of 155 fish species belonging to 49 families and 15 orders were recorded from the tidal freshwater zone of the Hooghly estuary. The exotic ornamental fish Barbonymus altus (Tinfoil Barb) has been recorded from the tidal freshwater zone which is the first record of these species in Indian inland waters. A detailed analysis of the fish diversity revealed that of the total 155 species recorded from the study, 19 species have been listed in category of threatened fishes by National Bureau of Fish Genetic Resources (Lakra et al., 2010). This includes 16 vulnerable (VU) species and 4 endangered (EN) species. This signifies the role of tidal freshwater zone as an essential fish habitat due to its rich fish diversity and as a sheltered area which favours the growth and survival of larval and juvenile fish assemblages.
Spatio-temporal distribution and community structure of zooplankton in the Gangetic Dolphin Sanctuary, 2009
Authors: Roy S. P. , Roy Richa , Prabhakar A. K. , Pandey Arpita , Kumar Ram , Tseng Li-Chun
Published: October 2017

The Vikramshila Gangetic Dolphin Sanctuary (VGDS) covers a 50 km stretch of the main channel of the Ganga River and is protected for the endangered freshwater dolphin (Platanista gangetica). We studied spatio-temporal patterns of zooplankton community structure during January through December 2009, at three sites. A total of 35 species including rotifers, cladocerans and copepods were identified. Integrating all samples, the top five dominant zooplankton included copepodids, copepod nauplii, B. caudatus, Ceriodaphnia rigaudi and Mesocyclops leuckarti. The zooplankton community was represented by diverse feeding groups including herbivores, carnivores, detritivores and bacterivores. The hierarchical dendrogram revealed distinct spatiotemporal variations. The Sultanganj community was separated at first hierarchical level, whereas species assemblage of August–October at Kahalgaon was distinguished at second hierarchical level. Top three indicative species at site-I (Sultanganj) were C. reticulata, Daphnia pulex and B. quadridentatus throughout the year. During monsoon the top three indicator species were C. rigaudi, M. leuckarti and B. falcatus at Bhagalpur and copepod developmental stages, B. caudatus and Keratella tropica at Kahalgaon. Adult Mesocyclops sp., copepod developmental stages and D. carinata were dominant in winter, whereas, Moina sp., C. rigaudi and M. leuckarti were the top three indicator species in summer at Bhagalpur and Kahalgaon. Of all the sites studied, Kahalgaon was recorded as having higher species richness.
Invasion and impacts of alien fish species in the Ganga River, India
Authors: Singh Atul K. , Kumar Dinesh , Srivastava Sharad C. , Ansari Abubakar , Jena J. K. , Sarkar U. K.
Published: October 2017

In this study, we document an increasing trend of catches of alien fish species from the Ganga River system. The changing fishery during 1980 to 2011 and the fish yield rate (kg km−1) are positively correlated with an invasion coefficient index (Ixi) of alien species within the river. The reproductive propagule pressure (PPP) of alien fishes (Cyprinus carpio, Oreochromis niloticus, Aristichthys nobilis, Ctenopharyngodon idella, Hypophthalmichthys molitrix and Clarias gariepinus) was determined and found to be 19.45×106 for C. carpio, 0.33×106 for O. niloticus and 0.82×106 for A. nobilis at confluences suggesting that these alien species may be migrating into new habitats. Further, these invaded species exhibited all reproductive stages, indicating their likely establishment within the river. The trophic spectrum of alien fishes spanned all levels and the gut repetitive index (GRI) indicated that that food items in most of the fishes were similar showing early trends of food-web alteration and biotic homogenization. The results of this study suggested a continuous decline in the catch of local fishes by wet weight, particularly Indian major carps (IMC) from 128.91 kg km−1 to 38.58 kg km−1 owing to increased catches of alien species from nil to 384.27 kg km−1. Invasion of alien species in the Ganga River represented one of many possible causes of the decline in river health and overall loss of native aquatic communities.
Metal and pesticide pollution scenario in Ganga River system
Authors: Samanta Srikanta
Published: October 2017

The River Ganga passes through a large number of cities, towns, villages and agricultural fields. A sizable fraction of effluents and sewages generated from all these diverse sectors enters into the river. The incoming water is, therefore, carrying huge amounts of organic substances, residues of the used pesticides and metals along with other contaminants. Review of the pesticide residue studies indicate that hexachlorocyclohexane (HCH), dichlorodiphenyltrichloroethane (DDT) and endosulfan were the major contaminants in water and biota while HCH, DDT, aldrin and dieldrin dominate the sediment phase. In water the residues are frequently crossing the permissible limits of US EPA standards for aquatic organisms and their consumers, indicating various levels of risk. In fishes, the permissible limits for HCH, endosulfan and DDT are exceed only in some occasions, signifying minor risks on human consumption. Regarding metal contaminations, the uppermost stretch, up to Haridwar, is relatively free from pollutions. The middle stretch, receiving diverse kinds of effluents, is markedly polluted. Although a significant stretch of the estuarine zone is densely industrialized and regularly receives effluents, the tidal action is maintaining the metals in lower level than the middle stretch. However, in majority of the cases the reported levels in water were much higher than the US EPA permissible limits for aquatic organisms. With respect to the metal contaminations in sediments, the river is found moderately polluted. In some fishes, contamination of Pb, Hg and Cr crosses the limits. However, the alkaline pH, high sediment transportation and rigorous flushing during monsoons are protecting the river from accumulation of these toxic contaminants. With respect to aquatic health, it is anticipated that the metal and pesticide contaminations might have adversely affected fish health. Systematic studies are, however, lacking on this aspect.
Management of Lake Victoria fishery: Are we looking for easy solutions?
Authors: Njiru M. , Van der Knaap M. , Taabu-Munyaho A. , Nyamweya C. S. , Kayanda R. J. , Marshall B. E.
Published: October 2017

Lake Victoria, East Africa, supports a fishery that yields about one million tonnes per annum consisting predominantly of three species, Nile Perch (Lates niloticus), Nile Tilapia (Oreochromis niloticus) and a native sardine-like cyprinid called Dagaa (Rastrineobola argentea). The non-native Nile Perch is the most valuable of these species and supports an important commercial export industry; there are fears that overfishing, due to the growth of fishing capacity, is threatening the Nile Perch fishery. Based on its economic importance and the notion that overfishing is threatening the resource, the current fishery management system was developed to control fishing capacity and effort. This system, using the concepts of co-management, where fishing communities and stakeholders participate through community organizations called Beach Management Units (BMUs) to actively manage the fishery in partnership with the central government, has been criticized that it is “fishery-based,” focusing on a single species and taking no account of ecological conditions in the lake, nor other species. A more “holistic” approach, which places a greater emphasis on changing nutrient concentrations and primary productivity as drivers of fish populations, has been proposed. Though fishery biologists and managers on Lake Victoria recognize that ecological conditions affect fishery populations, there appears to be two major challenges hindering the implementation of such approaches: first, the lack of a coherent objective of the Lake Victoria fishery, and second, the challenges associated with incorporating and implementing concepts of nutrient information and multiple species into a practical fishery management program.

This article describes the current fishery co-management program to determine the feasibility of implementing a holistic approach on Lake Victoria. It is concluded that whether a management system should be “holistic” or “fishery-based” is of little importance; what is needed on Lake Victoria are clear objectives and a management plan that will enable those objectives to be achieved, utilizing both ecological and fisheries data where appropriate.
Evaluating impairment in Wisconsin Areas of Concern using relative abundance of Smallmouth Bass
Authors: Fayram Andrew H. , Weigel Brian M. , Lyons John , Simmons Thomas
Published: October 2017

Smallmouth Bass (Micropterus dolomieu) is an important sportfish and has been suggested as a restoration target species in degraded aquatic environments such as “Areas of Concern” in the Great Lakes basin. Determining expected relative densities of fish and wildlife populations, such as Smallmouth Bass, in least-impacted situations is central to developing effective monitoring programs, assessing the level of relative impairment, determining appropriate restoration goals, and evaluating the efficacy of restoration efforts. We tested a straightforward classification scheme of Smallmouth Bass populations in least impacted non-wadeable rivers in Wisconsin based on parameters related to substrate and geographic location as both variables have been associated with relative Smallmouth Bass density. Coarse-substrate rivers tended to have higher Smallmouth Bass catch per effort values than fine-substrate rivers and southern rivers tended to have higher catch per effort values than northern rivers in Wisconsin. We used the expected Smallmouth Bass relative density estimates to assess the level of impairment of Smallmouth Bass populations in three Areas of Concern in Wisconsin (Milwaukee River and Estuary, Sheboygan River and Estuary, and the Fox River and Green Bay). We found that Smallmouth Bass catch per effort values were significantly higher in Areas of Concern than both the minimum and 25th percentile values for least-impacted rivers and were not significantly different from the median least-impacted values. Based on abundance, it does not appear that Smallmouth Bass populations are particularly impaired in these three Areas of Concern.
Effects of localized temperature and precipitation on historic Walleye recruitment in Wisconsin, USA with implications for climate change
Authors: Fayram Andrew H. , Tober Griffin Joanna D. , Wendel Jamison L.
Published: October 2017

Walleye (Sander vitreus) populations in Wisconsin are near the center of their geographical range and support valuable fisheries. The role of seasonal temperature and precipitation in Walleye recruitment was examined using regression tree analysis. Climatological variables were estimated at the 8 km2 scale and Walleye recruitment was estimated based on 298 individual electrofishing surveys. Estimated changes in Walleye recruitment between 1950 and 2006 were examined based on changes in explanatory climatological variables. Spring precipitation and summer maximum temperature were significant predictors of age-0 Walleye density and mean estimated changes in these variables between 1950 and 2006 were used to estimate changes in Walleye recruitment. The model predicted a small overall increase in Walleye recruitment and provides insight into the direct role of climatological variables in Walleye recruitment. However, given the low explanatory power (R2 = 0.103), it is likely that historic climatological changes have had a limited effect on recruitment levels.
Elucidation of ecosystem attributes of two Mackenzie great lakes with trophic network analysis
Authors: Janjua Muhammad Yamin , Tallman Ross , Howland Kimberly
Published: October 2017

The Mackenzie Basin in northwestern Canada is a high-latitude region, with one of the largest watersheds in the world. The Mackenzie great lakes, consisting of Great Bear Lake, Great Slave Lake and Lake Athabasca form the large lake complex. The human presence in the area is small in terms of population and industry and thus these ecosystems remain comparatively pristine and show no major changes in the fish communities. Ecopath with Ecosim (EwE), the most important and most used ecosystem trophic network modelling tool to study the ecosystem-level responses to changes, and information available in the scientific literature together with traditional knowledge about Great Slave Lake and Great Bear Lake was used to elucidate the ecosystem attributes. Our models give a cohesive view of these two ecosystems that will allow researchers and decision makers to explore questions regarding the stability of fisheries and future ecological change. The moderate trophic level of fish catch along with the small percentage of primary production required to sustain fisheries in both lakes demonstrated that fisheries were sustainable during the time period modelled. The ecosystem indices and attributes of the comparatively pristine Mackenzie great lakes were compared with those of two Laurentian Great Lakes having similar types of Ecopath ecosystem models. The metrics utilized to assess comparatively the ecosystem's maturity, stability and health indicated a decline in ecosystem maturity and stability from pristine Great Bear Lake to transitioning Lake Ontario.
On structure and maturity changes of the Bohai Sea ecosystem during the 1980s–1990s
Authors: Zheng Ting , You Xue-Yi
Published: October 2017

To quantify the historical ecosystem changes in the Bohai Sea, the Ecopath models (EWE 6.2) were developed in three time periods (1982–1983, 1992–1993 and 1998–1999), where measured data was available. The trends in the structure, maturity and keystone of the Bohai Sea ecosystem from 1982 to 1999 were assessed and planning and management measures were proposed. Numerical results indicated that (1) the ecosystem size of the Bohai Sea in terms of flow is becoming small; (2) the Bohai Sea has experienced a decline in maturity ascribed to the anthropogenic and natural factors; (3) the Bohai Sea ecosystem is in the developing state. In addition, organisms of the highest trophic level (trophic level ≥3.34), such as Squid, exert significant influences on the Bohai Sea ecosystem, but their biomass is declining. To alleviate and prevent further decline in the ecosystem size in terms of flow and maturity of the Bohai Sea, ecosystem-based management and abundance of organisms of the highest trophic level need to be considered in future conservation planning and management.
A modeling assessment of contaminant fate in the Bay of Quinte, Lake Ontario: Part 2. Organic chemicals
Authors: Gandhi Nilima , Diamond Miriam L. , Razavi Roshanak , Bhavsar Satyendra P. , Hodge Erin M. , Gewurtz Sarah B. , Arhonditsis George B.
Published: October 2017

A mass balance model of contaminant fate-transport was applied to 11 organic compounds in the Bay of Quinte and its foodweb. Total loadings were back-calculated from measured concentrations in sediment and/or fish for most chemicals due to limited measured concentrations in the contributing tributaries and point sources such as STPs. Total loadings decreased between 1988 and 2000 from 1–2 orders of magnitude for TCDD/F to 30% B[a]P and 80% for ΣPCBs. Total loadings in 2000 ranged from 10 mg day−1 for TCDD/TCDF to ∼0.01–0.5 kg year−1 for mirex, p,p′-DDT and BDE-47, to ∼1 kg year−1 for dieldrin and HCB, ∼10–50 kg year−1 for ΣPCB and B[a]P, and 2000 kg year−1 for atrazine. Despite concentration reductions, sport fish exceeded the lowest Ontario fish consumption guidelines for ΣPCB, TCDD and TCDF. Model results suggested that atmospheric deposition was the main source of lower molecular weight PCBs, TCDD/F and DDT, tributaries for higher molecular weight PCBs, and Lake Ontario for mirex, atrazine and dieldrin loadings. The main source of B[a]P was thought to be urban runoff, unknown for long-banned HCB and sewage treatment plants for 17β-estradiol. Results for BDE-47 were illustrative due to the lack of data. Industrial sources did not contribute to overall sediment or fish concentrations (not including “hot spots”). Organic compounds in the Bay were estimated to have a short residence time of days in the water column due to rapid export to Lake Ontario, except for HCB and 17β-estradiol which were estimated to be lost by volatilization and transformation, respectively. The response time of organic compounds in sediment varied from <1 year (atrazine) to ∼50 years (ΣPCB).
The saga of community learning: Mariculture and the Bolinao experience
Authors: David Laura T. , Pastor-Rengel Davelyn , Talaue-McManus Liana , Magdaong Evangeline , Salalila-Aruelo Rose , Bangi Helen Grace , San Diego-McGlone Maria Lourdes , Villanoy Cesar , Cordero-Bailey Kristina
Published: October 2017

The per capita fish consumption in the Philippines has not significantly changed through the years (1987–2003), but the increase in human population has created an ever-increasing demand for food fish. The Philippine Bureau of Fisheries and Aquatic Resources has responded to the food fish shortage by promoting mariculture. We support this policy within a comprehensive planning and management framework that includes siting and density of mariculture facilities. The case of Bolinao-Anda, Pangasinan is presented in this article to highlight the multi-faceted process for a successful mariculture enterprise. We use remote sensing tools to track the responses of stakeholder groups to various local legislation, mariculture-induced disasters, and scientific recommendations. Using hydrodynamic models, we assess these responses and highlight potential adjustments that may alleviate the pressure on and maintain the ecosystem health of the Bolinao-Anda coastal waters.
Spatial extent and dissipation of the deep chlorophyll layer in Lake Ontario during the Lake Ontario lower foodweb assessment, 2003 and 2008
Authors: Watkins J. M. , Weidel B. C. , Rudstam L. G. , Holeck K. T.
Published: October 2017

Increasing water clarity in Lake Ontario has led to a vertical redistribution of phytoplankton and an increased importance of the deep chlorophyll layer in overall primary productivity. We used in situ fluorometer profiles collected in lakewide surveys of Lake Ontario in 2008 to assess the spatial extent and intensity of the deep chlorophyll layer. In situ fluorometer data were corrected with extracted chlorophyll data using paired samples from Lake Ontario collected in August 2008. The deep chlorophyll layer was present offshore during the stratified conditions of late July 2008 with maximum values from 4–13 μg l−1 corrected chlorophyll a at 10 to 17 m depth within the metalimnion. Deep chlorophyll layer was closely associated with the base of the thermocline and a subsurface maximum of dissolved oxygen, indicating the feature's importance as a growth and productivity maximum. Crucial to the deep chlorophyll layer formation, the photic zone extended deeper than the surface mixed layer in mid-summer. The layer extended through most of the offshore in July 2008, but was not present in the easternmost transect that had a deeper surface mixed layer. By early September 2008, the lakewide deep chlorophyll layer had dissipated. A similar formation and dissipation was observed in the lakewide survey of Lake Ontario in 2003.
An Observing System Simulation Experiments framework based on the ensemble square root Kalman Filter for evaluating the concentration of chlorophyll a by multi-source data: A case study in Taihu Lake
Authors: Li Yuan , Li Yun-Mei , Wang Qiao , Zhu Li , Guo Yu-Long
Published: October 2017

Data assimilation is a method to produce a description of the system state, as accurately as possible, under the control of observations by using all the available information and by taking into account the observation and model errors. We developed a framework for Observing System Simulation Experiments (OSSEs) based on the ensemble square root Klaman filter (EnSRF) technique, and the framework could assimilate two data sets of chlorophyll a retrieved from Environmental Satellite 1 (HJ-1) and moderate resolution imaging spectro-radiometer (MODIS) onboard the Terra platform, separately. We assumed that one of the retrieved results was the proxy “truth value” and the other one contained errors. Based on EnSRF technique, combined with the three dimensional numerical model of wind-driven circulation and pollutant transportation in a large-scale lake, we investigated the potential impact of location distributions of simulated observation stations in Taihu Lake (China) on the performance of data assimilation. In addition, the effectiveness of this method for evaluation and prediction of the concentration of chlorophyll a was validated. The results showed that the location of simulated observation stations not only influenced the accuracy of evaluating and forecasting results, but also the performance of data assimilation. We also discuss the impact of assimilation time and background error on the results. This study demonstrated that this method of data assimilation is effective for evaluation and prediction of the concentration of chlorophyll a in highly turbid case 2 waters.
Seasonal and intraseasonal variability of surface chlorophyll a concentration in the South China Sea
Authors: Tang Shilin , Liu Fenfen , Chen Chuqun
Published: October 2017

Seasonal and intraseasonal variability of surface chlorophyll a concentration in the South China Sea is explored using the NASA standard Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) monthly and 8-day level-3 products from 1997 to 2007. The link between the seasonal and intraseasonal variability of the chlorophyll and physical forcing is revealed. Continuous wavelet transform indicates that chlorophyll in the South China Sea presents pronounced seasonal, as well as intraseasonal, variability. Chlorophyll a variability shows significant correlation with wind speed in all five sub-regions, while significant correlation with sea surface temperature only appears in the northern Sea. Intraseasonal variability of chlorophyll appears mainly in the winter, with spectral peaks around 32–64 days. It shows high commonalities for some periods in the intraseasonal cycle between chlorophyll a and sea surface temperature, wind stress curl or wind speed using cross wavelet transform.
Preliminary remote sensing observation of sea surface temperature increase during Ulva prolifera blooms
Authors: Wang Sufen , Tang Danling
Published: October 2017

A massive bloom of green macroalgae Ulva prolifera occurred in June 2008 in the Yellow Sea, resulting in perhaps the largest “green tide” event in the history of bloom research. The covered area is about 1,200 km2 and the impacted area reached 40,000 km2 on 31 May. This also occurred in the following two years, 2009 and 2010. We analyzed the satellite data from MODIS and the results showed that sea surface temperature increased 1–3°C in U. prolifera bloom locations. The macroalgae in the water may have been the cause of the increase of sea surface temperatures. Rapid increases of U. prolifera biomass during the blooms may have increased radiation absorption of the water, and thus enhanced the rate of heating at the sea surface. The present study represents a preliminary observation, which is an important step for understanding influences of macroalgae on ocean surface conditions.
Flow prediction using ENVISAT RA-2 sea surface height validated model: A case study for the effect of Hong Kong-Zhuhai-Macau Bridge in the Pearl River Estuary, China
Authors: Lu Jianzhong , Wai Onyx W. H. , Chen Xiaoling , Zhang Peng
Published: October 2017

The Delft3D-Flow hydrodynamic model was used to predict the impact of the Hong Kong-Zhuhai-Macau Bridge on the tidal flow in the Pearl River Estuary. In addition, the impacts of the flow currents on nearby bridge piers and artificial islands were assessed. To obtain additional spatial and temporal observations relative to the tidal gauge station observations, the sea surface height, which was derived from satellite altimetry ENVISAT RA-2, was closely correlated with the simulated tidal levels on individual days. These variables were modeled in the presence and absence of the Bridge, and the sea surface height validated numerical model was used to study the impacts of the Bridge on local water levels and circulation patterns. The construction of this Bridge resulted in small changes in tidal levels in that area. The average highest and lowest tidal levels changed by less than 0.01 m, which is about 0.4% of the highest tidal level and 2% of the lowest tidal level. The total tidal range changed by nearly 0.015 m. These results indicated that coastal engineering hardly affects the tidal flow in the Pearl River Estuary. In addition, complex eddy and circulation patterns were discovered near artificial islands. It is important to understand the complex flow patterns to ensure traffic safety during bridge construction and to determine the associated impacts of the bridge on tidal currents in the Estuary.
Temporal variability of chromophoric dissolved organic matter in the Pearl River Estuary, China from 2003 to 2009
Authors: Liu Fenfen , Tang Shilin , Chen Chuqun
Published: October 2017

The present study aims to investigate the temporal variability of chromophoric dissolved organic matter through remote sensing and to determine its influence factors in the Pearl River Estuary. A medium resolution imaging spectrometer, chromophoric dissolved organic matter product was evaluated with in situ absorption coefficient (R2 = 0.9605, RMS = 0.1672 and MRE = 0.3930). L2 daily products were then averaged into monthly data to analyze variability in the specified area from January 2003 to December 2009. Accumulated anomaly analysis and the wavelet analysis showed that the variability had a significant period of one year from 2003 to 2009, accompanied with 3 and 6 month periods in 2004 and 2008 separately. Cross wavelet transform was used to analyze the relationships between chromophoric dissolved organic matter and its influence factors including rainfall and phytoplankton in time frequency space. Relationships with salinity and light were also analyzed. It was found that photobleaching induces lower dissolved organic matter in summer even though there is greater discharge due to large rainfall intensity during this season. However, the anomalous strong precipitation may cause significantly higher findings in the study area. An example was a heavy flood caused by strong precipitation in 2008 induced higher findings for the period for less than half a year.