bluuebunny/crossref_metadata_2025_split huggingface dataset:
An overview of thirty years of research on ballast water as a vector for aquatic invasive species to freshwater and marine environments
Authors: Bailey Sarah A. 
Published: October 2017

Ballast water has been widely used by commercial vessels to control trim, draft and stability since the late 1870s. While the global transport of ballast water (and associated sediments) was first recognized as a potential dispersal mechanism for plankton in the late 1890s, quantitative research on the issue does not appear in the primary scientific literature until the mid-1980s. Following James T. Carlton's comprehensive review of the biology of ballast water in 1985, there was an explosion in research effort, with nearly 400 papers published in the last thirty years. This article provides a brief overview of the role that ballast water has played as a global vector for aquatic invasive species, summarizing the current state of ballast water research and emerging topics for future study, based on a review of articles in the primary scientific literature.
Initially, the main research focus was to document the community composition of ballast water in ships arriving to ports around the world. In the late 1990s, risk ssessments examining shipping traffic patterns and environmental tolerances of species likely transported in ballast water dominated. By 2000, ballast water studies examining efficacy of various treatment strategies dominated, and papers exploring new tools and methods for more accurate/representative sampling and analysis of ballast water emerged as an important research topic. There is currently insufficient data to confidently quantify the probability of invasion associated with any particular inoculum density (or discharge standard), as a result, laboratory, field and modeling studies examining the relationship between invasion risk and the size of the initially released population (the ‘risk-release relationship’) are an emerging, high priority field of study.
Environmental conditions, freshwater fishes and fishery management in the Ukraine
Authors: Movchan Yuriy V. 
Published: October 2017

Ukraine, with a total area of almost 604,000 km2, has 73,000 rivers and streams and about 20,000 lakes and estuaries. These aquatic resources belong to the Baltic Sea and the Black Sea (including the Sea of Azov) basins, and are inhabited by at least 137 fish species. Over the last 40–50 years, the freshwater fish fauna of Ukraine waters has changed considerably. Intensive fishing based on non-biological principles in the absence of aquaculture assistance caused significant degradation of fish populations: in particular, the replacement of long-life cycle species by short-life cycle species and “biological pollution” as a result of intentional and unintentional introductions. Twenty new exotic species were introduced and some of them became established. At the same time, a number of long-life cycle and migratory fishes, which were the most important for commercial fisheries, became extirpated. However, the growing number of nature reserves of different levels and categories gives some reasons to hope for stabilization of fish diversity in general and its possible improvements in the future. The freshwater fishery needs further modernization based on advanced principles that could guarantee a sustainable use of freshwater fish resources.
Assessment of fish species assemblage on mesohabitat scale: A case of middle stretch of Narmada River, India
Authors: Naskar Malay , Sahu S. K. , Sharma A. P. 
Published: October 2017

In river ecosystems, mesohabitat characteristics (i.e. pool, run, riffle, rapids, etc.) act as proximate variables to fish species occurrence. Fish occurrence and mesohabitat data are very often collected independently for different purposes, which invites challenges to characterize the fish species distribution pattern on mesohabitat scale. The present article delineates quantitative assessment of fish occurrence in relation to mesohabitat using secondary data. Middle stretch of the Narmada River of India has been selected for the study. Geographic information system tools have been used for integration of species and mesohabitat data. Nonmetric multidimensional scaling, cluster analysis and analysis of similarity techniques have been used for similarity analysis. Logistic regression model has been applied for model-based inferences on family-mesohabitat relationship. Two separate mesohabitat types, viz., Pool-Run and Run-Riffle, have been characterized by the fish species occurrence pattern. Dissimilarity of fish species composition between Pool-Run and Run-Riffle was statistically significant (p-value &lt; 0.05). The family-mesohabiat model predicted that the occurrence probability of a fish species was 14.49 times more in the Pool-Run than that in the Run-Riffle. The predictive accuracy of the model was 69.8%.
Periphyton responses to nitrogen and phosphorus enrichment of shallow lake systems dominated by submerged plants: A mesocosm study
Authors: Mei Xueying , Zhang Xiufeng 
Published: October 2017

The responses of periphyton to enrichment with nitrogen and phosphorus have been investigated in shallow lakes with low macrophyte biomass, but less is known about shallow lakes dominated by submerged plants. We examined the biomass and species composition of periphyton in 12 mesocosms dominated by Vallisneria natans (Lour.) Hara and subjected to different nitrogen and phosphorus enrichment regimes. Periphyton biomass measured as Chlorophyll a (Chl a) was higher in the nitrogen-enriched treatment relative to the controls. Chl a initially increased with phosphorus and nitrogen + phosphorus enrichment, but declined towards the end of the experiment. This delayed negative response of periphyton to nutrient enrichment appeared to be due to increased phytoplankton concentrations which inhibit light availability (nitrogen + phosphorus additions) and to increased growth of V. natans (phosphorus additions). Shifts in species composition of periphyton also occurred with different treatments. Our work demonstrated that periphyton are significantly affected by enrichment with nitrogen and phosphorus, and helped clarify the ecological role of these important primary producers.
Implications of climate warming for hydrology and water balance of small shallow lakes: A case of Wamala and Kawi, Uganda
Authors: Natugonza Vianny , Ogutu-Ohwayo Richard , Musinguzi Laban , Olokotum Mark , Naigaga Shamim , Kitabona Janet 
Published: October 2017

Climate variability and change that have been intensifying since the 1970s are accompanied by changes in hydrology and water balance of inland aquatic systems. These changes, however, have not been well documented with regard to small and shallow aquatic systems that are more vulnerable. Changes in temperature, rainfall and wind speed around Lakes Wamala and Kawi (Uganda) were examined to provide insight on how the increasing variability and change in climate affect water balance and lake water levels. Around Lake Wamala, average air temperature has increased by 0.018°C y−1 since 1980. Rainfall increased by 9.01 mm y−1 since 1970 and accounted for 79.5% of the water gain during 2011 and 2013 period. However, the gains were exceeded by losses as a result of evaporation that accounted for &gt;85% of the water loss. Despite the increase in rainfall, the mean lake depth of Lake Wamala decreased by 0.015 m y−1, apparently due to high evaporation rates. Around Lake Kawi, average air temperature has increased by 0.036°C y−1 since 1980. Rainfall, however, has decreased, although it still dominates the water inflows, accounting for 83% of the total water gains. Interviews with local fishermen on Lake Kawi indicated that the lake shoreline has receded by ∼50 m over the last two decades. These results suggested that most of the water in small shallow lakes is gained through direct rainfall, but more is lost through evaporation. Therefore, increase in rainfall around these lakes is no longer sufficient to sustain normal lake water levels and lake surface area as long as temperature and wind speed, which enhance evaporation, continue increasing. This has implications for lake productivity processes and needs to be understood and incorporated in management of fisheries and the catchment areas as climate warming intensifies.
Effect of four wetland plants on nutrient removal and growth of eutrophic algae
Authors: Zhong Tao , Tian Yun-Hui , Song Ben-Ru , Chen Zong-Jing , Zhang Yang , Chen Zhang-He 
Published: October 2017

We studied the removal of chlorophyll-a and eutrophic alga Ankistrodesmus acicularis by mixed and monoculture constructed wetlands of four common wetland macrophytes, Echinodorus berteroi, Hydrocotyle sibthorpioides, Vallisneria natans and Hydrilla verticillata. We also tested the effects of the macrophyte culture solution on the growth of three common eutrophic algae: Chlorella pyrenoidosa, Scnedesmus obliquus and Anabaena flosaquae.
The wetlands had significant effect on the removal of chlorophyll-a and A. acicularis. ANOVA results indicated a significant difference existed among different wetlands (P &lt; 0.01). There was generally no significant difference between the mixed and the monoculture wetlands, while the mixed wetlands generally showed significant difference between them.
Results also indicated that there were significant differences in the effect on the growth of three algae among the culture solutions of different wetlands (p &lt; 0.01). Almost all mixed culture solutions had a significant difference from their monocultures. Similarly, the monoculture treatments generally showed significant differences from their corresponding mixed treatments. However, combinations of different macrophytes generally cannot increase the effect intensity. The results indicated that combinations of macrophytes can produce different effects on alga growth from their monocultures and from their combinations with other macrophytes. Different algae showed different levels of susceptibility to the plant culture solution, and a same culture solution had different effects on different algae, including inhibiting, promoting, or neutral effects.
Contaminant concentrations and biomarkers in 21-day old Herring Gulls (Larus argentatus) and Double-crested Cormorants (Phalacrocorax auritus) from eastern Lake Ontario, and from Hamilton Harbour in western Lake Ontario in 1989 and 1990
Authors: Bishop Christine A. , Trudeau Suzanne , Janz David , Hughes Kimberley D. 
Published: October 2017

This study measured concentrations of polychlorinated biphenyls, polycyclic aromatic hydrocarbons, organochlorine pesticides, trace metals and biochemical markers of contaminant exposure and potential toxicity (plasma and hepatic retinol, hepatic retinyl palmitate, ethoxyresorufin O-deethylase, hepatic porphyrins) in 21 day-old Herring Gull (Larus argentatus) and Double-crested Cormorant (Phalacrocorax auritus) chicks. The chicks were collected from breeding colonies at Hamilton Harbour, an industrialized site in western Lake Ontario, and at Snake and Pigeon Islands in eastern Lake Ontario in 1989 and 1990. The polycyclic aromatic hydrocarbons, benzo[a]pyrene and naphthalene, were detected in bile and concentrations were higher in both species, but particularly in Cormorants, at Hamilton Harbour in comparison to eastern Lake Ontario. Ethoxyresorufin O-deethylase activity correlated positively with polyaromatic hydrocarbon exposure in Cormorants. At Hamilton Harbour, Cormorants had significantly greater liver to body weight ratios, increased hepatic ethoxyresorufin O-deethylase activities and elevated plasma retinol concentrations compared to those from eastern Lake Ontario. Liver concentrations of selected polychlorinated biphenyl congeners were generally low (&lt;2 ug g−1 w.wt) in birds from both areas but Hamilton Harbour Herring Gulls had mean concentrations that were significantly higher than eastern Lake Ontario Gulls, while Cormorants had low and similar polychlorinated biphenyl concentrations between sites. Trace metal levels did not vary substantially between sites for either species.
Population trends of colonial waterbirds nesting in Hamilton Harbour in relation to changes in habitat and management
Authors: Zanchetta Carolyn V. , Moore David J. , Weseloh D. V. Chip , Quinn James S. 
Published: October 2017

Since 1975, the diversity and abundance of colonial waterbirds breeding in Hamilton Harbour have increased, making it an important nesting site on the Great Lakes. An adaptive management approach has been employed to control hyper-abundant species and guide conservation efforts for vulnerable species, with the goal of maintaining a diverse waterbird community. Four species exhibited increasing or stable population trends (1975–2013): Double-crested Cormorants (Phalacrocorax auritus; from 0 to 4747 nests); Black-crowned Night-Herons (Nycticorax nycticorax; ranged from 6 to 259 nests); Herring Gulls (Larus argentatus; from 0 to 244 nests); and Caspian Terns (Hydroprogne caspia; from 0 to 496 nests). Cormorants are currently above (2,500 nests), while Caspian Terns (400–600 nests), Night-Herons (100–200 nests) and Herring Gulls (200–300 nests) are within population targets set out in the Hamilton Harbour Remedial Action Plan. Despite conservation efforts, Common Terns (Sterna hirundo) declined from a peak of 1,028 nests (1990) to 333 nests (2013), although currently within the population target (300–600 nests). Ring-billed Gulls (L. delawarensis), through long-term management and habitat restrictions, were reduced from a peak of 39,621 nests (1990) to 11,133 nests (2013), but still exceed the target (&lt;10,000 nests). Changes in the amount of available habitat have affected waterbird distributions: the loss of 42 ha (peak in 1999) of former nesting areas to development has been partially offset by the creation or securement of 1.9 ha of dedicated breeding habitat. Continued management, assessed and refined annually, is required to maintain species diversity in the area. Current management techniques focus on preventing Ring-billed Gulls from nesting on private lands and dedicated Tern nesting habitat, excluding Cormorants from nesting at specific sites, and reducing inter-specific competition with Night-Herons and Herring Gulls. Recommendations and considerations regarding future management and conservation efforts to reach Remedial Action Plan targets in the harbor are outlined.
Glider-observed anticyclonic eddy in northern South China Sea
Authors: Shu Yeqiang , Xiu Peng , Xue Huijie , Yao Jinglong , Yu Jiancheng 
Published: October 2017

Using high-resolution in situ data from gliders, satellite data of sea level anomaly and geostrophic currents, we presented the detailed structure of an anticyclonic eddy during spring 2015 in the northern South China Sea. The impact depth of the anticyclonic eddy reached about 1000 m and had a maximum temperature anomaly of about 3°C at ∼120 m and maximum salinity anomaly of more than 0.3 psu in the mixed layer. The maximum geostrophic velocities perpendicular to the glider path were about 0.3 m s−1 at 100 m. The estimated radius was about 72 km and the translation velocity was about 5.2 cm s−1. The rotational speed of the eddy was estimated to be 0.35 m s−1. The high temperature and large salinity of the anticyclonic eddy indicated it did not originate from the South China Sea locally. The analysis of water mass indicated the character of the eddy water was similar to Kuroshio water, and the time evolution of the sea level anomaly and surface geostrophic velocity anomaly further validated that it originated from the Kuroshio intrusion as a loop current to the southwest of Taiwan.
Long-term variations in oxygen in sub-tropical coastal waters: Influence of sewage effluent
Authors: Yuan Xiangcheng , Huang Hui , Zhou Weihua , Yuan Tao , Li Xiubao , Gao Yongli , Liu Sheng 
Published: October 2017

The increase in population in the Pearl River delta region has increased domestic sewage and industrial discharges, which influences biogeochemical (e.g. carbon dioxide release) and environmental (e.g. oxygen depletion) conditions. Dissolved oxygen and dissolved inorganic carbon concentrations along with salinity, temperature, pH, and chlorophyll a at the surface were collected during seven cruises at eight stations in different months in 2005–2006 to document the seasonal influence of anthropogenic inputs on dissolved oxygen in different areas of Hong Kong waters. Long-term data during 1997–2006 were used to assess air-sea exchange of dissolved oxygen. Near the Pearl River estuary, dissolved oxygen was undersaturated, while partial pressure carbon dioxide was oversaturated, which indicated that Pearl River estuary influenced waters were heterotrophic and represented net sources of carbon dioxide to the atmosphere. In Victoria Harbour, where there was greater sewage effluent influence, however, the degree of dissolved oxygen undersaturation was even more than the Pearl River estuary influenced waters throughout the year. In contrast, the eastern waters, where there was less influence of anthropogenic inputs, showed seasonal variability: undersaturation of dissolved oxygen (∼90%) in the dry season shifting to slight oversaturation (∼105%) in the wet season. The monthly average air-sea influx of oxygen decreased by ∼50 to 200 mmol m−2 d−1 in the wet season relative to that in the dry season in Victoria Harbour, which was coupled with an increase in chlorophyll a from the dry to wet season. These findings are important in understanding why the eutrophication impact from nutrient enrichments in Hong Kong waters is not as severe as one would expect, and also how sewage effluent influences biogeochemical processes of dissolved oxygen and carbon in coastal waters.
Studies on ecology, fish diversity and fisheries of Ken–Betwa rivers (India): Proposed for inter-linking
Authors: Joshi K. D. , Alam Md. A. , Jha D. N. , Srivastava K. , Srivastava S. K. , Kumar V. , Sharma A. P. 
Published: October 2017

The Ken and Betwa rivers traversing through Central India are the major tributaries of the river Yamuna. Both rivers originate above 550 m above sea level in the Vindhya region. An interlinking project proposed for the rivers envisages diversion of water from Ken basin to the Betwa. The river sediment is alkaline and dominated by sand (78–89%) in both rivers. Oxygen-rich alkaline water and moderate values of chemical parameters show the pollution free and productive nature of both the rivers. There was no statistically significant difference in water quality between the Ken and Betwa rivers, except for total alkalinity. The biotic parameters were observed in similar ranges and moderate condition. A total of 61 planktonic forms were recorded from the rivers out of which 55 were phytoplankton. For the first time, 89 fish species belonging to 10 orders, 26 families, and 62 genera have been recorded in the river Ken, while 81 species classified under 10 orders, 24 families, and 55 genera were found in the Betwa. Exotic fish species were also observed in the downstream stretches of both rivers. Out of the total fish species, 77 were common to both rivers, 12 were found only in the Ken River, and 4 species were restricted to the Betwa. Analysis of relative abundance showed dominance of Labeo boggut in the Ken and Osteobrama cotio in the Betwa River. On comparison of the Shannon–Wiener Diversity and Evenness Indices of fish diversity, these indicated slightly higher values in the Ken (3.76 and 0.842) than the Betwa (3.66 and 0.835). A total of nine near-threatened fish species was recorded in the rivers. Both rivers have already been obstructed by many developmental projects; the proposed interlinking would further negatively impact the ecology and fisheries.
Elevated zooplankton production in a eutrophic Lake Ontario embayment: Hamilton Harbour 2002–2014
Authors: Bowen K. L. , Currie W. J. S. 
Published: October 2017

Hamilton Harbour is an Area of Concern in western Lake Ontario, long stressed by cultural eutrophication, urbanization and invasive species. Despite high nutrient levels leading to hypolimnetic hypoxia and contaminated sediment, it is a highly productive environment. To better understand zooplankton dynamics in Hamilton Harbour, we conducted biweekly May to October sampling of zooplankton and rotifer composition at open water harbour sites from 2002–2014. May to October zooplankton density, dry biomass and total production averaged 265 ± 16 animals l−1, 306 ± 19 mg m−3 and 4131 ± 359 mg m−3, (±SE), respectively. These values are among the highest reported in the Great Lakes, with biomass two to seven times greater than in other eutrophic embayments. Zooplankton populations and taxonomic seasonality have remained relatively stable in Hamilton Harbour since 2002. Biomass is often dominated by smaller taxa such as Bosmina, Eubosmina and juvenile copepods, suggestive of high fish planktivory, but Daphnia retrocurva and D. galeata mendotae are also dominant during the summer, indicating improvements in the zooplankton community since the 1970s when Daphnia and cyclopoids were uncommon. Conversely, rotifers have declined over the last 40 years, though while still numerically dominant, now comprise &lt;4% of total biomass and production compared to 40% in the 1970s. Both adult Dreissenid Mussels and their veliger larvae are less abundant in Hamilton Harbour compared to nearshore Lake Ontario. Zooplankton appear to be effectively utilizing high production rates of edible algae and microorganisms in the harbour. More work is needed to explore trophic interactions in this eutrophic ecosystem and the effects of hypolimnetic hypoxia on the zooplankton community.
Microbial - Planktonic foodweb dynamics of a eutrophic Area of Concern: Hamilton Harbour
Authors: Munawar M. , Fitzpatrick M. 
Published: October 2017

Hamilton Harbour, located on the western end of Lake Ontario, has a long history of cultural eutrophication as well as industrial contamination. We explored the structure and function of the microbial – planktonic foodweb during the growing seasons (May–October) of 2004 and 2006 in order to consider the flow of autochthonous production from lower to higher trophic levels. Our analyses included microscope based assessments of bacteria, heterotrophic nanoflagellates, ciliates, phytoplankton and zooplankton as well as radioisotope based measurements of primary productivity and bacterial growth. While routine measures of total phosphorus (avg: 25–33 µg l−1) and chlorophyll a (avg: 12–15 µg l−1) were indicative of eutrophy, mean phytoplankton biomass in 2004 (2.0 g m−3) and 2006 (2.2 g m−3) suggested mesotrophic conditions. However, the appearance of algal blooms in the summer of 2006 was an obvious indicator of cultural eutrophication. With respect to the microbial – planktonic foodweb, the organic carbon pool increased from a mean of 757.5 mg C m−3 in 2004 to 1160.3 mg C m−3 in 2006 and this increase was almost evenly split between autotrophs (198.7 mg C m−3) and heterotrophs (204.1 mg C m−3). The increased autotrophic carbon is readily attributable to the observed algal blooms driven by warmer temperatures and higher concentrations of soluble reactive phosphorus. However, the increase in heterotrophic carbon, primarily heterotrophic nanoflagellates, was apparent from the earliest observations in 2006 and remained consistently high throughout the year. We hypothesize that the increased heterotrophic carbon was the consequence of increased allochthonous carbon being shunted through the microbial foodweb; the energy generated was not likely transferred to zooplankton and passed on to higher trophic levels. More research into the dynamics of allochthonous and autochthonous carbon in eutrophic environments is called for.