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Baetidae; DNA; barcoding; claws; conservation status; females; genetic distance; genetic markers; genetic variation; gills; males; models; nymphs; rivers; species diversity; water quality; watersheds; Andes region
Abstract:
... Andesiops peruvianus is widely distributed in the Andean region and has been preliminarily used as a bioindicator of good water quality. Given the morphological variations that are reported for the species, this study aimed to address whether such morphological variability in nymphs captured in tributaries of the Upper Chinchiná River Basin, Caldas-Colombia, could be connected to genetic differenc ...
aeration; agricultural runoff; constructed wetlands; cost effectiveness; energy; municipal wastewater
Abstract:
... With the unique advantages of cost-effectiveness and low energy consumption, constructed wetlands (CWs) are commonly used for treatment of secondary municipal wastewaters. Over the last decades, CWs have gained increased popularity for treating agricultural runoff and agro-industrial wastewater. This review highlights the practice, application, and research on wetland technology, placing them in t ...
... In shallow freshwater ecosystems, submerged macrophytes and algae usually compete for nutrients, light and space. Previous studies mainly focused on the growth effects (biomass, growth rate, photosynthetic activities) of algae by submerged macrophytes. The present study found that submerged macrophytes could also have morphological influences on green algae. We used the green alga Chlorella vulgar ...
community structure; dams (hydrology); ecosystems; fish; fish communities; floodplains; hydrology; introduced species; macrophytes; models; oligotrophication; rivers; species diversity; temporal variation; uncertainty
Abstract:
... We investigated correlates of long-term temporal variation in the beta diversity of macrophytes, sedentary fish, and migratory fish communities in the Upper Paraná River floodplain. Two metrics of among-site variation in community composition were calculated in up to 45 sampling periods over 12 years for each biological group. We then tested the following beta diversity correlates: richness and pr ...
Ekaterina P. Shchapova; Denis V. Axenov-Gribanov; Yulia A. Lubyaga; Zhanna M. Shatilina; Kseniya P. Vereshchagina; Ekaterina V. Madyarova; Eugeniy S. Protasov; Maxim A. Timofeyev
Amphipoda; acute exposure; acute toxicity; aquaculture; aquatic environment; ecosystems; enzyme activity; fisheries; lipid peroxidation; littoral zone; monitoring; oils; petroleum; stress response; water reservoirs; water solubility; Lake Baikal; Russia
Abstract:
... The current study evaluated the possible toxic effects of the water-soluble fraction of crude oil on the general cellular stress-response mechanisms of two dominant representatives of Lake Baikal’s littoral community, the endemic amphipod species Eulimnogammarus verrucosus and E. cyaneus. The acute toxicity effects on the cellular stress-response mechanisms of amphipods were studied in the laborat ...
... To identify the mechanisms whereby substrate embeddedness and water velocity influence Nooksack dace (Rhinichthys cataractae subsp. cataractae) prey capture efficiency, we stocked dace in foraging arenas with varying substrate types over a range of velocities (0, 25, 35 cm s⁻¹) and measured their efficiency of prey capture. We stocked a known number of mayfly (Ephemeroptera), black fly (Simuliidae ...
... Environmental DNA (eDNA) is a powerful method for assessing the presence and distribution of invasive aquatic species. We used this tool to detect and monitor several invasive crayfishes Procambarus clarkii, Orconectes limosus and Pacifastacus leniusculus present in, or likely to invade, the ponds of the Brenne Regional Natural Park. A previous study showed that the eDNA method was not very effici ...
Artemia franciscana; animals; dormancy; hatching; models; photoperiod; salinity; Portugal; Spain; United States
Abstract:
... Dormancy, the physiological start of rest, occurs in numerous animal species. Many crustaceans release various types of encased embryos in a state of dormancy (e.g., cysts, ephippia, etc.). These dormant propagules require specific combinations of abiotic environmental cues to terminate dormancy. Our goal was to determine if population-specific responses to varying levels of salinity and light (ph ...
climate change; dissolved organic carbon; energy transfer; fish; fish production; phytoplankton; planktivores; trophic levels; zooplankton; Northern European region
Abstract:
... Climate change projections indicate increased precipitation in northern Europe, leading to increased inflow of allochthonous organic matter to aquatic systems. The food web responses are poorly known, and may differ depending on the trophic structure. We performed an experimental mesocosm study where effects of labile dissolved organic carbon (DOC) on two different pelagic food webs were investiga ...
... Brycon amazonicus is widely distributed in the Amazon basin. The species has traditionally been the focus of subsistence and commercial fisheries, and recently has become an important aquaculture species. Aquaculture relies on the removal of individuals from nature which form the basis of breeding stocks. The breeding stocks are often derived from local populations, but equally often are a mix of ...
... The impact of fine sediments on both habitat quality and macroinvertebrate communities of riverine systems has been well documented over recent years. However, there is a paucity of studies examining the mechanisms that relate macroinvertebrate sensitivity and responses of individual macroinvertebrate species to burial by sediment. Laboratory-based burial experiments were undertaken to study the r ...
Lates niloticus; carbon; environmental factors; fish; fish communities; invertebrates; omnivores; primary productivity; stable isotopes; stomach; trophic levels; wet season; Lake Victoria; Tanzania
Abstract:
... Stable isotope analyses and derived population-level metrics were used to quantitatively analyse spatial and seasonal heterogeneity in the fish trophic dynamics in relation to environmental variables in Mwanza Gulf, Lake Victoria (Tanzania). The fish community in Lake Victoria, including the top predator Nile perch, is generally omnivorous with a heavy reliance on invertebrates. This is in contras ...
Cyprinus carpio; abnormal development; breeding stock; climate change; eggs; energy; fish development; food intake; freshwater fish; hatching; larvae; models; morphometry; temperature; yolk sac; France; Northern European region
Abstract:
... The aim of the present study is to test the effects of temperature on the early life stages of one of the most common freshwater fish species worldwide, the common carp. About 16,000 eggs coming from 3-year-old broodstock were randomly distributed into five incubators, one incubator by tested temperature (16, 18, 20, 22, and 24°C). Several parameters (survival and malformation rates, development t ...
Torgeir B. Havn; Eva B. Thorstad; Maxim A. K. Teichert; Stein A. Sæther; Lisa Heermann; Richard D. Hedger; Meelis Tambets; Ola H. Diserud; Jost Borcherding; Finn Økland
Salmo salar; mortality; power plants; predation; radio frequency identification; risk; rivers; smolts; turbines; water power
Abstract:
... We studied downstream migration of 256 radio-tagged Atlantic salmon smolts passing a low-head power station where technical facilities have been improved to allow safe migration via several bypass routes. Extra mortality was 7 and 17% (two years) in the power station reservoir, and a minimum of 10 and 13% at the power station compared to in a control stretch. The majority of the smolts followed th ...
... Instream large wood (LW) constitutes an indispensable element of natural river ecosystems. It affects local hydraulics, morphology, nutrient budget, overall habitat complexity, and dynamics. Despite numerous studies about LW as a habitat for benthic communities, information on the varying importance along the longitudinal gradient of a river is lacking. The focus of this study is therefore to inve ...
... Species diversity can be a result of environmental and spatial constrains that act at small and large spatial scales. An important question in community ecology is to know the contribution of each one in studies with multiple spatial scales. We examined aquatic insect assemblages in small streams from the Atlantic Forest in a mainland-island scenario, with the aim of measuring which variables expl ...
... The genus Chaetoceros is among the most species-rich marine planktonic diatoms. Most Chaetoceros are considered important primary producers in various marine environments, but because of their small size, we know little about their ecology and distribution. Therefore, from 2008 to 2012, we examined the occurrence of C. tenuissimus Meunier, one of the smallest members in the genus, and its infectio ...
... A number of modelling results suggested thermocline shifts as a consequence of global climate change in stratifying lakes. Abundance and composition of the phytoplankton assemblage is strongly affected by the stratification patterns, and therefore, change in the thermocline position might have a substantial effect on this community or even on the whole lake ecosystem. In this study, thermocline de ...
... Understanding the evolutionary response of organisms to environmental gradients is important in light of increasing anthropogenic changes to our environment. In this study, we use ecological genetic tools to determine local adaptation of the model organism, Daphnia pulicaria, across a pH gradient in three North American lakes. We predicted that there would be genetic differentiation and local adap ...
... Unregulated rivers provide unobstructed corridors for the dispersal of both native and invasive species. We sought to evaluate range size and habitat use of an invasive species (Silver Carp, Hypophthalmichthys molitrix) in an unimpounded river reach (Wabash River, IN), to provide insights into the dispersal of invasive species and their potential overlap with native species. We hypothesized that r ...
... Acidification has adversely affected freshwater ecosystems in many areas, and recovery from acidification is often interrupted by acidic events. We lack detailed information about how benthic algae react to short-term acidic events and long-term recovery from acidification. We sampled 15 stream sites in the Czech Republic to study the effects of (a) water pH, aluminium and lead concentrations, (b) ...
... We aim to test the hypothesis that an assemblage of characid fishes coexist by partitioning food resources. We calculated dietary niche overlap of four syntopic species of the Characidae using gut content analysis. Secondly, we used a carbon (¹³C) and nitrogen (¹⁵N) isotope Bayesian mixing model to estimate relative assimilation. All characids consumed large proportions of plant material and aquat ...
... Several studies have shown that the origin of carbon fuelling food webs in streams depends on riparian cover type. In forested stream sites allochthonous resources fuel food webs, whereas autochthonous resources support biomass in grassland (open-canopy) stream sites. However, some studies suggest that autochthonous carbon (of highest quality) is preferentially assimilated regardless of riparian c ...
... Ecological applications of stable isotope data require knowledge on the isotopic turnover rate of tissues, usually described as the isotopic half-life in days (T ₀.₅) or the change in mass (G ₀.₅). Ecological studies increasingly analyse tissues collected non-destructively, such as fish fin and scales, but there is limited knowledge on their turnover rates. Determining turnover rates in situ is ch ...
... The production of diapausing eggs is an ecological strategy commonly used by zooplanktonic organisms to cope with adverse conditions in time-varying habitats. Traits related to diapause (e.g., the time spent in diapause, the hatching fraction of diapausing eggs, or the amount of reserves allocated to them) should be combined by natural selection to favor adaptation to particular habitat conditions ...
Bacillariophyceae; Cyanobacteria; aquatic ecosystems; biomass; case studies; intermediate flow; mixing; models; moieties; nutrient content; nutrients; phytoplankton; rain; stochastic processes; water flow; wet season; Brazil
Abstract:
... We analyzed the temporal (dry and rainy periods) and spatial (zones) phytoplankton biomass variation (FGs—functional groups) in a tropical reservoir, and determined the main drivers. We hypothesized that water flow negatively affects the FG–environment relationship because high flow promotes dispersal stochasticity. Our results indicated that the FG–environment relationship was affected mainly by ...
... Territorial farmer damselfishes are facilitators that selectively farm turf algae in degraded reef patches. The effect of damselfish on algae and corals has been widely studied but the ability of the damselfish to establish farms on other substrates is less understood. In the giant clam ocean nursery in Bolinao, northwestern Philippines, farmer damselfishes, particularly Stegastes nigricans, Disch ...
Maria W. Pil; Rafael A. Baggio; Marcel K. Tschá; Flávio M. Marteleto; Raphael Orélis-Ribeiro; Luciana Patella; Marcelo Chammas; Antonio Ostrensky; Walter A. Boeger
... The present study sought to identify general patterns of genetic variability and structure of fish stocks (migratory and non-migratory species) along one of the largest Brazilian rivers, the São Francisco. Given that genetic variability of populations of all organisms is governed by both present and past influences, herein we investigate both these aspects by evaluating the current genetic differe ...