copepod Articles
-
Impact of Microzooplankton and Copepods on the Growth of Phytoplankton in the Yellow Sea and East China Sea
Dilution and copepod addition incubations were conducted in the Yellow Sea (June) and the East China Sea (September) in 2003. Microzooplankton grazing rates were in the range of 0.37–0.83 d-1 in most of the experiments (except at Station A3). Correspondingly, 31–50% of the chlorophyll a (Chl a) stock and 81–179% of the Chl a production was grazed by microzooplankton. At the end of 24 h copepod ...
-
Biochemical responses of the copepod
Centropages tenuiremis to CO2-driven acidified seawaterAn ecophysiological experiment was conducted to examine the biochemical effects of acidified seawater containing elevated concentration of CO2 (CCO2 0.08, 0.20, 0.50 and 1.00%) on the copepod Centropages tenuiremis. AchE, ATPase, SOD, GPx, GST, GSH level and GSH/GSSG ratio of the copepod were analyzed. The results showed that elevated CCO2 and the duration of culture time significantly influenced ...
-
Planktonic microbial assemblages and the potential effects of metazooplankton predation on the food web of lakes from the maritime Antarctica and sub-Antarctic islands
Antarctica is the continent with the harshest climate on the Earth. Antarctic lakes, however, usually presents liquid water, at least during part of the year or below the ice cover, especially those from the sub-Antarctic islandsand the maritime Antarctic region where climatic conditions are less extreme. Planktonic communities in these lakes are mostly dominated by microorganisms, including ...
-
Toxicity of ZnO nanoparticles to the copepod, Acartia tonsa, exposed through a phytoplankton diet
Zinc oxide (ZnO) nanoparticles (NPs) are being increasingly utilized in a variety of products and applications and are therefore commonly discharged into aquatic environments, increasing exposure and potentially impacting aquatic organisms. ZnO NPs can depress growth of some marine phytoplankton, and several examples of NP trophic transfer have been documented, although not within planktonic ...
-
Benzoylurea pesticides used as veterinary medicines in aquaculture: Risks and developmental effects on non‐target crustaceans
Diflubenzuron and teflubenzuron are benzoylureas that are used in aquaculture to control sea lice. Flubenzurons have low toxicity to many marine species such as fish and algae, but by their nature are likely to have significant adverse effects on non‐target species such as crustaceans and amphipods. Although the exact mechanism of toxicity is not known, these compounds are thought to inhibit ...
-
Evaluating aquatic invertebrate vulnerability to insecticides based on intrinsic sensitivity, biological traits and toxic mode‐of‐action
In this study we evaluated the vulnerability of aquatic invertebrates to insecticides based on their intrinsic sensitivity and their population‐level recovery potential. The relative sensitivity of invertebrates to five different classes of insecticides was calculated at the genus, family and order levels using the acute toxicity data available in the USEPA AQUIRE database. Biological trait ...
-
Ecological characteristics of plankton and aquatic vegetation in Lake Qiluhu
Investigations of the phytoplankton, zooplankton, zoobenthos and aquatic vegetation in Lake Qiluhu were carried out in February, 2009. Over the whole lake, 13 sampling sites were set up for the analysis of phytoplankton and zooplankton, and 22 profiles for the collection of macrophytes and zoobenthos. In the survey, 7 phyla, 65 algae species were identified. The average abundance of ...
-
Standardized methods for acute and semichronic toxicity tests with the copepod Acartia tonsa
The availability of standardized protocols for both organism culture and bioassay with ecologically relevant species is of great concern in ecotoxicology. Acartia tonsa represents an important, often dominant, member of zooplankton communities and meets all the practical criteria suggested for model species. New standardized procedures for laboratory culturing of the copepod A. tonsa and ...
-
Stage‐dependent and sex‐dependent sensitivity to water‐soluble fractions of fresh and weathered oil in the marine copepod Calanus finmarchicus
Acute toxicity differs between species but also varies within a species. Important intraspecific factors are the exposure duration and properties of the animal such as life stage, sex, and physiological status. In the present study, the acute toxicity of water‐soluble fractions (WSFs) from fresh and artificially weathered oil was followed over time in different life stages of the calanoid ...
-
Feeding habits of the juvenile striped weakfish, Cynoscion guatucupa Cuvier 1830, in Bahía Blanca estuary (Argentina): seasonal and ontogenetic changes
The aim of this study was to analyze the feeding habits of the juvenile striped weakfish, Cynoscion guatucupa Cuvier, from Bahía Blanca estuary, Argentina. C. guatucupa is one of the most important regional fishing resources although in the last 10 years landings have greatly decreased. The year class strength of fish as well as stock size and yield are determined during the early life stages. ...
-
Chronic aquatic effect assessment for the fungicide azoxystrobin
This study examined ecological effects of a range of chronic exposure concentrations of the fungicide azoxystrobin in freshwater experimental systems (1270 L outdoor microcosms). Intended and environmentally relevant test concentrations of azoxystrobin were 0, 0.33, 1, 3.3, 10, 33 μg ai/L, kept at constant values. Responses of freshwater populations and community parameters were studied. Over ...
-
Characteristics of suspended solids affect bifenthrin toxicity to the calanoid copepods, Eurytemora affinis and Pseudodiaptomus forbesi
Bifenthrin is a pyrethroid pesticide that is highly toxic to aquatic invertebrates. The dissolved concentration is generally thought to be the best predictor of acute toxicity. However, for the filter feeding calanoid copepods, Eurytemora affinis and Pseudodiaptomus forbesi, ingestion of pesticide‐bound particles could prove to be another route of exposure. The present study investigated ...
-
Synthetic estrogen directly affects fish biomass and may indirectly disrupt aquatic food webs
Endocrine‐disrupting chemicals are known to alter the fitness of individual organisms via changes in growth, behavior, and reproduction. It is largely unknown, however, whether these effects cascade through the food web and indirectly affect other, less sensitive organisms. The authors present results from a mesocosm experiment whereby the effects of the synthetic estrogen 17α‐ethinylestradiol ...
-
A critical body residue approach for predicting persistent bioaccumulative toxicant effects on reproduction and population dynamics of meiobenthic copepods
Critical body residues (CBRs) are the measured tissue toxicant concentrations yielding a median dose–response on a dry‐weight or lipid‐normalized basis. They facilitate management decisions for species protection using tissue analysis. Population CBR is the mean dose yielding 50% population suppression and was predicted here in Amphiascus tenuiremis for fipronil sulfide (FS) using lifetables and ...
-
Secondary production of freshwater zooplankton communities exposed to a fungicide and to a petroleum distillate in outdoor pond mesocosms
Ecological Risk Assessment (ERA) of chemicals in mesocosms requires measurement of a large number of parameters at community scale. Studies on invertebrate communities usually focus on taxonomic approaches which only provide insights into taxonomic structure changes induced by chemicals. In the present study, abundance, biomass (B), theoretical production (P) and instantaneous P/B ratio were ...
-
Urban and agricultural pesticide inputs to a critical habitat for the threatened delta smelt (Hypomesus transpacificus)
The Cache Slough complex is an area of tidal sloughs in the Sacramento‐San Joaquin River Delta of California, and is surrounding by irrigated agricultural lands. Among the species of concern in the area is the delta smelt (Hypomesus transpacificus), a federally‐listed threatened species. Releases of the organophosphate insecticide chlorpyrifos and pyrethroid insecticides were examined to ...
Need help finding the right suppliers? Try XPRT Sourcing. Let the XPRTs do the work for you