Isolation and characterization of polymorphic microsatellite loci in Wuchang bream (Megalobrama amblycephala)

Wuchang bream (Megalobrama amblycephala) is an economically important fish in China. From a (GT)(13)-enriched genomic library, 20 microsatellites were developed. Nine of these 20 loci were polymorphic in a test population with allele numbers ranging from two to four, and the observed and expected heterozygosities ranging from 0.2609 to 0.7826 and from 0.3739 to 0.7546, respectively. In the cross-species amplifications, six of these nine loci were also polymorphic in white amur bream (Parabramis pekinensis). These polymorphic microsatellite loci are potentially useful for population genetics of Wuchang bream and its closely related species.Wuchang bream (Megalobrama amblycephala) is an economically important fish in China. From a (GT)(13)-enriched genomic library, 20 microsatellites were developed. Nine of these 20 loci were polymorphic in a test population with allele numbers ranging from two to four, and the observed and expected heterozygosities ranging from 0.2609 to 0.7826 and from 0.3739 to 0.7546, respectively. In the cross-species amplifications, six of these nine loci were also polymorphic in white amur bream (Parabramis pekinensis). These polymorphic microsatellite loci are potentially useful for population genetics of Wuchang bream and its closely related species

University of South Carolina publications. Series 3. Biology. V.3 No.1

This publication is volume 3, issue 1 of the University of South Carolina Publications. Series III. Biology. on taxonomic studies of the flora and fauna of South Carolina

Application of FTIR spectroscopy for monitoring water quality in a hypertrophic aquatic ecosystem (Lake Auensee, Leipzig)

FTIR spectroscopy as molecular fingerprint has been used to assess macromolecular and ele-mental stoichiometry as well as growth rates of phytoplankton cells. Chemometric models have been developed to extract quantitative information from FTIR spectra to reveal macro-molecular composition (of proteins, carbohydrates and lipids), C:N ratio, and growth potential. In this study, we tested these chemometric models based on lab-cultured algal species in mon-itoring changes of phytoplankton community structure in a hypertrophic lake (Lake Auensee, Leipzig, Germany), where a seasonal succession of spring green algal bloom followed by cya-nobacterial dominance in summer can be commonly observed. Our results demonstrated that green algae reacted to environmental changes such as nitrogen limitation (due to imbalanced nitrogen and phosphorus supply) with restricted growth by changing carbon allocation from protein synthesis to storage carbohydrates and/or lipids, and increased C:N ratio. By contrast, cyanobacteria proliferated under nitrogen limiting conditions. Furthermore, the FTIR-based growth potential of green alga matched well with the population biomass determined by the Chl-a concentration. However, the predicted growth potential based on FTIR spectroscopy cannot describe the realistic growth development of cyanobacteria in this lake. These results revealed that green algae and cyanobacteria have different strategies of C-allocation stoichi-ometry and growth patterns in response to environmental changes. These taxon-specific re-sponses may explain at a molecular level why green algae bloomed in the spring under condi-tions with sufficient nutrient, lower pH and lower water temperature; while cyanobacteria overgrew green algae and dominated in the summer under conditions with limited nutrient availability, higher pH and higher water temperature. In addition, the applicability of these chemometric models for predicting field cyanobacterial growth is of limited value. This may be attributed to other special adaptation properties of cyanobacterial species under stress growth conditions. We used flow cytometry to isolate functional algal groups from the water samples. Despite some drawbacks of the flow cytometry combined FTIR spectroscopy tech-nique, this method provides prospects of monitoring water quality and early warning of harmful algal blooms

Protozoa parasitic in fish

Imperial Users onl

Biological invasions in brackish waters

Invasive non-native species (NNS) cause deleterious ecological, economic, social impacts worldwide. Brackish waters are transitional areas subject to invasion by taxa that may subsequently spread into adjacent freshwater and marine systems. The tendency for ports to be situated in brackish estuaries makes them particularly susceptible to ship-borne introductions of NNS. Despite being reported as heavily invaded ecosystems with a disproportionately high abundance of NNS, studies on biological invasion in brackish waters has received considerably less attention than truly freshwater and marine systems. In this thesis, I investigate the discovery, ecological impacts, and management of NNS in brackish waters. I begin by conducting a systematic review and meta-analysis comparing the ecological impacts of NNS in brackish, freshwater, and marine environments around the globe. I reveal that NNS have led to an overall decrease in the abundance and diversity of the resident communities in freshwater and marine environments, but not in brackish waters. NNS in brackish estuaries provide novel habitats, which can facilitate the establishment of other NNS, leading to an invasional meltdown. Next, I explore the first records of all freshwater, brackish and marine NNS in Great Britain and show that many NNS were first discovered in estuaries and often aggregated around the major shipping ports. This result provides support that many marine and freshwater NNS in Great Britain could have been introduced via international ships visiting brackish waters. I then focus on one NNS, the Gulf wedge clam, Rangia cuneata, which is a brackish water bivalve currently invading European waterways. I show that the growth and feeding rates of R. cuneata differed at the two extremes of salinity tolerated by this species, and consider how this intraspecific variation might drive context-specific ecological impacts. I go on to demonstrate the potential detrimental impacts of R. cuneata as a result of their much higher feeding rates and greater functional responses compared to a sympatric, native unionid mussels. I finish by investigating two methods to control invasive species in brackish waters. I show that using saline, but not freshwater, shock could effectively control R. cuneata. I then demonstrate the effectiveness of two new formulations of microencapsulated biocides in controlling R. cuneata. Taken together, these studies provide important insights into the discovery, impacts and management of NNS in brackish waters. My findings demonstrate the need for greater monitoring for NNS in brackish systems, and especially those subject to high ship traffic. The control methods proposed here have wide application in many brackish systems and for many species, thus providing much needed effective tools for the rapid response to the discovery of high risk invasive NNS in this important but overlooked transitional habitat.This study is funded by a Gulbenkian Yuval Cambridge Studentship at Churchill College and a Graduate Scholarship from Natural Sciences and Engineering Research Council of Canada

Detritus and microbial ecology in aquaculture

Proceedings of the 1985 Bellagio Conference on Detrital Systems for Aquaculture held in Bellagio, Como, Italy, to analyze and summarize available information on detrital food chains and the means for their manipulation in aquaculture. Contains 16 papers and related discussions.Detritus, Food chains, Microbial ecology, Aquaculture

Carp genetic resources for aquaculture in Asia

There are over 1 300 species of cyprinids in Asia, which form an important part of the worldÆs aquatic biodiversity. Aquaculture and capture fisheries involving cyprinids are a vital part of the livelihoods of many millions of people in this region. The production of carps from aquaculture in Asia constitutes over half of world finfish aquaculture production. Further growth in human populations will increase the demand for carps as food, but may also threaten wild populations. This publication focuses on carp genetic resources for aquaculture in major carp producing countries of Asia viz., Bangladesh, China, India, Indonesia, Thailand and Vietnam, describing the species of importance, our current knowledge of the genetics of these species and genetic improvement of these species for aquaculture.Carp, Fish culture, Aquaculture, Genetic resources, Fishery resources, Asia,

Hydrology-Shaped Plant Communities

Aquatic ecosystems and the water they hold have attracted people over the centuries. With the technological development and increasing needs of human society, the attitude to water and aquatic ecosystems has changed. Consequently, biodiversity of freshwater ecosystems has declined dramatically and it is still decreasing. Anthropogenic exploitation of these ecosystems and alterations of their hydrology has largely influenced hydrology-shaped plant communities. This Special Issue, “Hydrology-Shaped Plant Communities: Diversity and Ecological Function” brings new outcomes about the interactions between hydrological factors and wide spectrum of plant communities. In ecosystems, where human activities directly or indirectly affected the hydrological factors, dependent plant communities have also changed or even disappeared. These plant communities have multiple ecological functions, and one of the most important are the maintenance of water quality and enhancement of local and regional diversity of other biotic communities like diatoms, invertebrates or fish. Thus, detailed knowledge and suitable management of hydrology-shaped plant communities is a prerequisite for their unconstrained ecological functions and high diversity of aquatic ecosystems in the widest sense. The Special Issue consists of ten peer-reviewed papers on plant communities in a variety of ecosystems - from the small kettle-holes in the lowlands of northern Germany to the river Danube - the largest river within the European Union, and from different wetland types in Central Europe to the Donggting Lake – fourth largest lake in China