Dispersal is one of the main determinants of metacommunity assembly, yet its interaction with the landscape network structure has not been fully elucidated. Large-scale regional factors such as the centrality–isolation gradient influence community abundance and richness, but small-scale regional factors, such as the direction or the distance among water bodies, might also influence them. Furthermore

The establishment probability of introduced alien fish can be context dependent, varying according to factors including propagule pressure and biotic resistance. The influence of nutrient enrichment on establishment outcomes of alien fishes is uncertain, yet this is a common anthropogenic stressor of many freshwaters. Here, the small-bodied alien topmouth gudgeon Pseudorasbora parva was used in mesocosms

Meiofaunal organisms are the predominant metazoans in benthic systems and important members of the benthic food web. They are defined by mesh size and specifically by their retention on a sieve with a 44-µm mesh size. In this study, we examined the accuracy of this standard collection method by counting the number of meiobenthic individuals, life stages and nematode species in a sample. A filter cascade

Meiofaunal abundance, biomass and secondary production were investigated over 13 months in an unpolluted first-order stream. Four microhabitats were considered: sediment and the biofilms on dead wood, macrophytes and leaf litter. The relative contribution of the microhabitats to secondary production and the influence of environmental factors on meiofaunal density distribution were estimated. We expected

The ciliate–metazooplankton trophic coupling is well documented from both laboratory and field experiments. The knowledge about these relationships during winter ice-covered periods is very scarce. The abundance and composition of planktonic ciliates, rotifers and crustaceans were studied during the ice-covered and ice-free periods in the Łuczański Canal (Masurian Lakeland, Poland). We hypothesised

Light affects bivalve behavior and gaping activity, but its potential effects on bivalve filtration remain poorly investigated. In this study, clearance rates of two bivalve species: the Asian clam, Corbicula fluminea and the paper pondshell, Utterbackia imbecillis, were assessed in light (6.5 ± 0.5 µmol m−2 s−1) and dark (0.0 µmol m−2 s−1) conditions. We found that clearance rates remained similar

The aim of this review is to analyze the literature on the impact of beavers on lakes, summarize their effects, describe consequences for biotic and abiotic components, and highlight unresolved issues and perspectives. Beaver activity changes vegetation structure to the greatest extent, indirectly affecting other ecosystem components. Damming of flowing lakes increases the littoral area, which affects

Deforestation of riparian areas is a major driver of biodiversity loss in aquatic ecosystems. Thus, we investigated the influence of forest cover and physical and chemical characteristics of streams on zooplankton communities in the southeastern Amazon. We addressed the following questions: (1) Are environmental factors (water physical and chemical characteristics and landscape variables) and dispersive

The non-indigenous colonial tunicate Didemnum vexillum plagues many shellfish aquaculture operations around the world by smothering crop and gear and displacing juvenile bivalves. There are two populations of D. vexillum in Oregon, but little is known regarding their spatial extent, seasonal dynamics, annual variability, reproductive biology, or ecology. SCUBA divers monitored the seasonal variation

Environmental heterogeneity and productivity are factors driving beta diversity of freshwater communities. Further, characteristics as spatial extent and connectivity, as well as land use and cover, can determine local biodiversity patterns. We evaluated the correlates of within-lake beta diversity of phytoplankton communities in 25 coastal shallow lakes in southern Brazil. We hypothesize that within-lake

Marine macroalgae serve as habitats that provide ideal shelter for a rich and diverse community of associated molluscs, but the true effects of the complexity of these habitats on fauna are still poorly understood. Replicates of four macroalgal species: Gracilaria domingensis (Kützing) Sonder ex Dickie 1874, Solieria filiformis (Kützing) Gabrielson 1985, Gracilaria cuneata Sonder ex Kützing 1859 and

Shrimp aquaculture has caused broadscale shifts in mangrove ecosystems worldwide, including changes in habitats and functional traits of mangroves, to the point of widespread destruction in some countries. The propagule is an important stage in mangrove life history, reflecting the resource investment of parents and the ability of offspring to build a population. However, the impacts of shrimp aquaculture

River regulation has altered the seasonal timing of flows in many rivers worldwide, impacting the survival and growth of riparian plants. In south-eastern Australia, demand for irrigation water in summer often results in high river flows during a season that would naturally experience low flows. Although unseasonal high summer flows are thought to significantly impact waterways, their effects on vegetation

Salinity can compromise the growth of aquatic macrophytes, influencing their nutrient content and interspecific interactions. In estuaries, the sediment characteristics vary in salinity as well as nutrient availability, granulometry and microbiota. The use of artificial substrates in manipulative experiments allows the evaluation of the isolated effect of salinity on plants. We evaluated the effects

The common octopus Octopus vulgaris Cuvier, 1797, once considered a cosmopolitan species, is a species complex composed by six species: O. tetricus, O. cf tetricus and O. sinensis in the Pacific; type I and II, in the West Atlantic; and type III in the Indian Ocean around South Africa. The tropical western central Atlantic is an important octopus fishing ground targeting O. maya, O. insularis, and

Rivers are heterogeneous and patchy-structured systems in which regional biodiversity of aquatic communities typically varies as a function of local habitat conditions and spatial gradients. Understanding which environmental and spatial constraints shape the diversity and composition of benthic communities is therefore a pivotal challenge for basic and applied research in river ecology. In this study

Two subspecies of bottlenose dolphins are observed, not simultaneously, in a narrow coastal area of the western South Atlantic Ocean. However, their trophic interaction is unknown. Such information can be explored using stable isotope composition in teeth, warranting time series data. We analyzed carbon and nitrogen isotopic values (δ13C and δ15N) of dentin growth layer groups in teeth of Tursiops

Fish–habitat relationships are a key element for conservation and management strategies, especially in highly disturbed areas where fish communities are subjected to many human pressures. In this regard, multiscale studies help to improve the knowledge of the spatial components and identify local (e.g. water width) and regional (e.g. elevation) key variables in species distribution. We examined local

Lake littoral environments are heterogeneous, and different organisms typically show specific responses to this environmental variation. We examined local environmental and spatial factors affecting lake littoral biodiversity and the structuring of assemblages of phytoplankton, zooplankton and macroinvertebrates within and among three basins of a large lake system. We explored congruence of species

Many methods of controlling invasive crayfishes have limited success because they fail to target all life stages of the population, notably by capturing only large adults that can result in increased juvenile recruitment by removing intraspecific predation. An alternative approach uses the sterile male release technique that involves the mass release of sterile males into the environment, which then

We tested whether changes in water transparency caused either by precipitation-mediated sedimentation (inorganic turbidity) or eutrophication (organic turbidity) differently interact with top predator presence to determine predation rates, and individual decisions of mesopredators between foraging and avoiding predators. We tested the hypothesis that fear-induced cascade effects are more pronounced

Successful coexistence with predators depends on the ability of prey to strike a balance between the costs of predator avoidance and the benefits of foraging and reproducing as there is a trade-off between these activities. Prey animals can balance this trade-off by responding to predation risk in a manner that matches the intensity of risk posed by the predator, which is known as the threat-sensitive

The East Asian common octopus Octopus sinensis is a bottom-dwelling species, but goes through a planktonic phase as ‘paralarvae’ during the first several weeks of life. As the swimming performance of the paralarvae is relatively poor, their dispersion relies primarily on ocean currents; however, vertical swimming may play an important role in their horizontal dispersion by controlling their buoyancy

Climate change can result in multiple indirect alterations of the environment in riverine ecosystems, due to changes in precipitation and runoff. Flow velocity, concentrations of CO2 and nutrients are thereby expected to change, and consequences of the combination of those effects for macrophytes, a key organism group, are still poorly understood. This was tested in a racetrack flume experiment on

Strategies of resource acquisition are subject to change due to introduced pressures placed upon individual animals. The pressures of food deprivation and competition can lead to a drastic change in previously established strategies of resource acquisition. We conducted a series of trials in which red swamp crayfish (Procambarus clarkii) were either deprived of food or satiated and competition was

Stormwater retention ponds receive a variety of urban and highway pollutants that may have adverse effects on water-dwelling organisms. In this exploratory study, the benthic diatom community composition at genus level of nine such ponds servicing highway, residential, industrial, and mixed industrial/residential catchments was examined. Thirteen biocides were measured in the pond water as one of the

Large wood (LW) is an indispensable element in riverine ecosystems, especially in lower river parts. The presence of LW significantly shapes local hydraulics, morphology, the nutrient budget; promotes overall river dynamics; and additionally presents a unique habitat for numerous benthic invertebrate species. Therefore, LW is recognized as valuable asset for river restoration measures. Experiences

Predicting fish community structure in streams is a challenge considering the strong dynamics of these environments. In this study, we tested whether using a fish dataset obtained in a previous time was relevant to predict fish community structure in a subsequent time. We also tested whether temporal beta diversity of fish communities was correlated with environmental variability, stream size and order

Egeria densa and Elodea canadensis are two common invasive submerged macrophytes in streams and rivers worldwide. We conducted a six-week growth experiment with monocultures of E. densa and E. canadensis and mixed communities of the two species under five different shade levels (35%, 63%, 79%, 90% and 95%). Our aim was to test the effect of shade and competition on colonization of vegetative propagules

Marine planktonic copepods frequently exhibit diel feeding cycles coupled with vertical migrations. However, copepod feeding rhythms can be influenced by factors others than different food availability between layers. In this study, we determined the changes in the diel feeding behaviour of two marine copepod species (Centropages typicus and Paracartia grani) through multigenerational laboratory rearing

Summer and perennial planktonic rotifers from temperate regions can vary greatly in their ability to reproduce at low temperatures. The population growth rate (r day−1) of a Patagonian Keratella tropica was 0.025 at 3.9 °C and gradually increased to 0.083 at 9.3 °C. The ability of this rotifer to survive and reproduce at low winter temperatures suggests that populations in permanent waters with cold

Although freshwater systems comprise a small portion of land surface, they play a pivotal role in landscape carbon (C) cycling. Carbon processing by heterotrophic bacteria is critical, contributing to ecosystem production and dissolved organic carbon (DOC) processing. Riverine bacterial C metabolism is related to a diversity of factors, including (1) physiochemical conditions and inorganic nutrient

Patterns of abundance and shell morphology of intertidal gastropods are typically thought to depend on environmental conditions, but ecosystem engineers such as canopy-forming seaweeds can also influence these traits. The intertidal seaweed Hormosira banksii (H. banksii) is an abundant species and important ecosystem engineer on rocky shores and estuaries in south-east Australia, where it creates thick

The storied Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri; YCT) population of Yellowstone Lake, Yellowstone National Park, Wyoming, USA, has shown a profound and mostly continuous decline since the 1970s despite pristine habitat and vanishing angler harvests. An age-structured Leslie model that had a broad climate index as its only driver (regulating age-0 YCT survival) was Bayesian-fitted

This study investigates the morphological changes in cyanobacterial and microbial distribution characteristics of surface sediments, throughout different cyanobacterial blooms periods in Zhushan Bay, Taihu Lake. Comparative microscopic analysis of cyanobacterial morphology (n = 36) was performed during the formation period (W1), stationary period (W2), decline period (W3) and decomposition period (W4)

Phytoplankton growth and degradation are associated with bacterial communities in phycosphere. We compared the bacterial communities in two algal blooms (Microcystis aeruginosa and Euglena sanguinea). In particular, large particle-associated, small particle-associated, and free-living bacteria were collected in succession using membranes with three different pore sizes (10 µm, 1 µm, and 0.22 µm) in

While transfer of freshwater cyanobacteria to estuaries has been observed worldwide, the associated transfer of cyanotoxins is less often reported, in particular the sediment contribution. During fall 2018, we monitored the co-occurrence of cyanobacteria and microcystin (MC) in both the water column and in surface sediments at five stations along a river continuum, from a freshwater reservoir to the

The study and monitoring of communities within microbiomes is important as some organisms can synthesize toxic substances, such as cyanotoxins synthesized by cyanobacteria. Cyanobacteria is a large portion of the periphyton biomass and is responsible for toxic blooms in aquatic environments. This makes urban environments an interesting environment for observing cyanobacteria diversity, due to the disturbances

Macroinvertebrate signature traits’ and ecological preferences’ distribution patterns and their responses to urban and agricultural pollution were explored in rivers-draining urban–agricultural catchments within the Niger Delta ecoregion of Nigeria. Physico-chemical variables (water temperature, electrical conductivity, depth, flow velocity, dissolved oxygen, biochemical oxygen demand, nitrates and

Many biological sources of sound in tropical coastal shallow-water marine environments remain unidentified. Characterizing the soundscape of such environments requires that all sources of biological sound be examined for their distinct patterns and specific frequency ranges. The present study identified soniferous fish in the ecosystem and measured underwater ambient sound in terms of its sound pressure

Population structure studies play an increasingly integral role in conservation and management of marine mammal species. Genetic markers are commonly used; however, ecological markers (i.e. chemical compounds) are a fairly recent and useful tool to investigate ecological management units. The objective of this study is to investigate the population structure of the Atlantic spotted dolphin (Stenella

Foraging is key for most animals, because their energy and matter income depend on food ingestion. However, animals may respond adaptively to perceived competitor and/or predator proximity by modifying their foraging rates. Increased foraging activity is expected to improve the chances of succeeding in competition. However, the benefits of increased foraging activity could be offset by the risks of

Amphibian chytridiomycosis panzootic is ongoing and continuing to have extensive worldwide impact on amphibians. Severity of chytridiomycosis-associated amphibians declines is partly associated with species’ altitudinal ranges. Michoacán state in México harbors 54 amphibian species on a wide range of climates, including high-altitude areas (above 3000 masl), suitable for Bd growth, such as the Monarch

During their ontogenetic development, many species of fishes undergo drastic changes which may be defined as true metamorphosis when they are induced by thyroid hormones. Sicyopterus lagocephalus is an amphidromous goby that has to change biome twice during its life cycle. The first biome shift occurs few hours after hatching in the river. The aim of the present study is to determine what external/environmental

Biological invasions are a growing threat to global biodiversity due to negative impacts on native biota and ecosystem functioning. Research has expanded from investigating native and alien species interactions to examining relationships among alien species. Invasive crayfish may have similar life histories, niche preferences, and adaptation strategies, but their mutual interactions are little understood

Serious cyanobacterial blooms lead to the release of harmful microcystin-LR and ammonia to eutrophic waters, thereby posing serious challenges to zooplankton. The physiological and ecological responses of Brachionus calyciflorus Pallas to microcystin-LR and ammonia stresses were evaluated. Neonates (< 2 h old) were exposed to microcystin-LR (0, 10, 50, 100, and 200 µg L−1) and ammonia (0, 740, and

Fish diversity is generally high in drainage networks in perennial systems. On the other hand, little is known about the importance of drainage networks in semiarid regions. The scant attention given to rivers in semiarid regions so far may in part be explained by the high intermittency and low ramification of these drainage networks and their incorrect classification as systems of low diversity and

Spatial and temporal complexities of reproductive behaviour and sex ratios of two harpacticoid species Canuella perplexa Scott T. & Scott A., 1893 and Bryocamptus sp. were evaluated monthly from September 2007 to August 2008. Collections were made from four ponds at different salinities in the solar saltern of Sfax, Tunisia, considering other environmental features as well. The salinities ranged from

Abstract In studies on coral–algal interactions, particular attention has been devoted to corals. Focusing on the macroalgal genus Lobophora (Dictyotales, Phaeophyceae), common on coral reefs and extensively studied in coral–algal interactions, this review aims to summarize what is known and highlight the conditions necessary for Lobophora blooms, the contrasting effects on corals, and the taxonomic

Abstract Most temporary pond zooplankton species produce drought-resistant eggs that accumulate in the sediment and form an egg bank. When a pond dries and the egg bank is exposed, wind erodes eggs and wind action has been suggested as an important determinant of population demographics. While field observations suggest that egg bank erosion may be highest shortly after pond drying and physical disturbance

Abstract The Classical Karst (sensu stricto) represents a complex hydro-geomorphological unit as well as one of the best-known karstic systems in the world. For this reason, it was selected as a model area both for applied research and for the conservation of its highly diverse subterranean fauna. With this paper, we aim to provide an overview of groundwater fauna in the phreatic zone of the Classical

Abstract Variation in biomass allocation patterns has been considered a strategy in clonal plants to adapt to various environments. It has been predicted that clonal plants allocate more biomass to spacers (i.e., stolon and rhizomes) at moderate resource levels. We tested the prediction in an aquatic clonal plant Salvinia natans by subjecting it to nine nutrient levels under either a low or a high

Abstract Predators shape the phenotype of prey by means of local adaptation, within-generation plasticity, and transgenerational plasticity. Theory predicts that the influence of these three mechanisms on phenotype is determined by the number of generations exposed to the predator and the autocorrelation between parent and offspring predator environments. To test theoretical predictions about the relative

In freshwater environments, the relative contributions of top-down and bottom-up effects on invertebrate communities in relation to productivity are largely ecosystem dependent. Artificial wetlands are increasingly developed to compensate for the loss of natural wetlands; however, their trophic processes remain poorly studied. The present study aimed to evaluate the respective contributions of bottom-up

Within the Gulf of Aden, Djibouti is an important site where whale sharks (Rhincodon typus Smith 1828) aggregate seasonally; however, up to now, only few studies have been carried out in the area (Rowat et al. in Environ Biol Fishes, 2007. https://doi.org/10.1007/s10641-006-9148-7; Mar Freshw Res, 2011. https://doi.org/10.1071/MF10135; Rezzolla and Storai in Cybium 34:195–206, 2010). From 2015 to 2018

Despite the fact that native species of amphipods have been recognized as active predators similarly to invasive species, little is known about their predatory impact on aquatic communities. In this study, we used a laboratory experiment, a field enclosure experiment, and an analysis of natural community data to demonstrate how Gammarus fossarum affects the species composition of benthic communities

To understand interactions between ecological properties of ostracod species and the habitat types, 89 different aquatic bodies with nine different habitat types were randomly visited in Artvin province, Turkey. A total of 24 taxa, all new for the province, were found from 62 sites. Shannon–Weaver alpha diversity of the numbers of species value was higher (3.972) than the mean index value of all samples

Understanding the drivers of species distribution is an important topic in conservation biology and ecology, pertaining to species traits like dispersal strategies and species–environment interactions. Here we examined the drivers of benthic species distribution at 20 sections of a second-order stream network. Environmental and spatial factors and the dispersal modes of the organisms were considered

The decomposition of dead organic matter is a key process for the metabolism and functioning of lotic ecosystems. Particulate organic matter from fallen leaves is the main source of energy input also in forested springs. However, detritus processing in spring habitats has been rarely investigated. The present paper is aimed to assess, for the first time, the influence of detritus origin on leaf litter

Invasive aquatic plants constitute a great problem in many freshwater systems. Although many studies have addressed the potential threats of invasion by exotic species in aquatic ecosystems, few studies have considered the interactions (competition, facilitation, coexistence) between exotic aquatic plants of similar growth form in invaded communities. Our aim was to investigate experimentally the effect