The effects of mixing different leaf litter species on litter decomposition in streams have received considerable attention in recent years. However, contrasting results have been reported and the mechanisms behind the effects of litter diversity have been poorly examined. We compared the decomposition rates and associated fungi for two contrasting litter species, when incubated individually and in

Diverse communities are more productive than less diverse ones because of two overyielding mechanisms: a selection effect and a complementarity effect, which operate in different ways. Moreover, ecosystem multifunctionality is expected to increase and become more stable with increasing species diversity. However, it is unclear how the aforementioned processes operate in aquatic ecosystems, where the

Partial migration, whereby a population comprises multiple behavioural phenotypes that each have varying tendencies to migrate, is common among many animals. Determining the mechanisms by which these phenotypes are maintained is important for understanding their roles in population structure and stability. The aim here was to test for the temporal and spatial consistency of migratory phenotypes in

Lake surveys conducted in 1987–88 and 2018–19 show changes in the chemical and optical properties of Adirondack lakes recovering from acidification. Among chronically acidified lakes (1980s pH < 5.5, ANC < 0 µeq L−1), increases in pH and reductions in monomeric Al were accompanied by significant increases in light attenuation, DOC, and CDOM. DOC-specific dissolved color (CDOM:DOC) doubled over the

Although detritivorous Tubificinae and chironomid larvae are important groups in functioning of both, fresh and brackish water ecosystem, their co-occurrence patterns in sediment is weakly known. We carried out two-year-long research in the brackish Vistula Lagoon (southern Baltic Sea), where both Tubificinae (Limnodrilus hoffmeisteri and Potamothrix hammoniensis) and larvae of Chironomus balatonicus

Concentrations of lipid-phosphorus (LP) in aquatic ecosystems can be influenced by algal biomass and the nutritional state of microbial communities, potentially serving a useful indicator of P-limitation. We examined the effectiveness of LP as a bioindicator by examining concentrations of LP and environmental factors controlling its abundance across Lake Erie and its tributaries. LP concentrations

In alluvial plains, where shallow lakes are subject to inputs of sediments, the impact of turbidity on predator–prey interactions needs to be studied. We conducted an in situ mesocosm study in a shallow floodplain lake during 36 days to evaluate the main and interactive effect of fish predation and turbidity on the abundances, composition and habitat selection of a natural aquatic assemblage, including

A correction to this paper has been published: https://doi.org/10.1007/s00027-021-00785-9

Winter stream temperatures, though infrequently studied, exert important influences on aquatic communities. To quantify effects of watershed physical characteristics on stream winter thermal regime, 54 streams (watershed area = 0.2–7.9 km2; altitude < 1300 m) on the Olympic Peninsula, Washington, USA were monitored hourly for 4 years. During the study, an exceptionally warm winter (2015) was used to

Due to the higher anthropogenic impacts, streams from urban regions are expected to suffer more damage than those from rural regions. This study investigated whether environmental changes caused by human activities negatively affect the variability in ecomorphological and dietary characteristics of the ichthyofauna from ten streams (five urban and five rural). Contrary to expectations, ecomorphological

The process of chemosynthesis can represent an important source of organic matter and energy across the benthic zone. However, its detailed vertical distribution and importance in relation to other microbial processes are still poorly investigated in inland aquatic ecosystems. Here, we determined the rates of dark inorganic carbon fixation (DCF) compared to heterotrophic bacterial production (BP) and

Droughts are expected to become more common with climate change resulting in more frequent occurrences of flow intermittency in temperate streams. As intermittency has deleterious effects on fluvial microbial biofilms, there is a need to better understand how droughts affect the microbial functioning and thereby nutrient and organic matter processing in temperate stream ecosystems. Here, the hyporheic

Knowledge of the habitat associations and spatial–temporal distributions of wild animals is essential for successful ecosystem management, and effective analytical approaches are key to develop accurate models of these relationships. We explore the influence of several modeling techniques, tuning parameters, and assignment thresholds on a variety of model fit metrics to characterize habitat associations

In floodplain lakes, precipitation events shape the environmental heterogeneity and the occurrence of species and functional traits. However, the importance of each biotic and abiotic factor on structuring communities might depend on the local environmental conditions and the identity of such communities. We investigated through Permutational analyses of variance and functional β-diversity components

Harmful blooms of the filamentous cyanobacteria Planktothrix rubescens have become common in many lakes as they have recovered from eutrophication over the last decades. These cyanobacteria, capable of regulating their vertical position, often flourish at the thermocline to form a deep chlorophyll maximum. In Lake Zurich (Switzerland), they accumulate during stratified season (May–October) as a persistent

Greenhouse gas (GHG) emissions from freshwater streams are poorly quantified in sub-tropical climates, especially in the southern hemisphere where land use is rapidly changing. Here, we examined the distribution, potential drivers, and emissions of carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) from eleven Australian freshwater streams with varying catchment land uses yet similar hydrology

Aquatic plants are vital components of shallow aquatic ecosystems, and they can substantially contribute to food webs. However, the large spatial and temporal variations of δ13C and δ15N signatures of aquatic plants have hindered the interpretation of their trophic interactions with organisms at higher trophic levels, and the effects of temperature on plant isotopic signatures remain to be fully elucidated

Freshwater lakes are essential hotspots for the removal of excessive anthropogenic nitrogen (N) loads transported from the land to coastal oceans. The biogeochemical processes responsible for N removal, the corresponding transformation rates and overall removal efficiencies differ between lakes, however, it is unclear what the main controlling factors are. Here, we investigated the factors that moderate

The role of nitrogen and phosphorus in promoting cyanobacterial blooms has been researched for many decades. In contrast, much less is known about the effect of trace metals on regulating cyanobacterial bloom formation. This is particularity relevant for nitrogen-fixing species, as some trace metals act as co-factors in nitrogenase and nitrite reductase enzymes. In the present study, we assessed the

The interactions between sediment microbial assemblages and submerged macrophytes in aquatic ecosystems can be potentially regulated by benthic macrofauna, and the regulation effect may be closely related to macrophyte species with distinct properties; however, little information on this is available. An aquarium experiment was designed to evaluate the role of snail Bellamya aeruginosa (Reeve) in regulating

Hydroperiod is considered an important aspect in shaping community structure and ecosystem patterns in temporary wetlands. However, most studies have focused on the community structure, demonstrating that biotic diversity increases with hydroperiod. Theory suggests that ecosystem patterns like trophic interactions and food web structure will also respond to hydroperiod in the same way. However, there

Heterocystous Cyanobacteria of the genus Nodularia form major blooms in brackish waters, while terrestrial Nostoc species occur worldwide, often associated in biological soil crusts. Both genera, by virtue of their ability to fix N2 and conduct oxygenic photosynthesis, contribute significantly to global primary productivity. Select Nostoc and Nodularia species produce the hepatotoxin nodularin and

Macroinvertebrates play a key role in aquatic food webs, with amino acids (AA) playing an important role in determining their nutritional value to higher consumers. This study aimed to determine whether AA profile varies among four macroinvertebrate taxa, spatially and seasonally (summer/winter). The freshwater prawn, Macrobrachium australiense; freshwater shrimp, Paratya australiensis; freshwater

Recently, it has been reported that freshwater browning has less effect on planktonic invertebrate abundances than would be expected from current knowledge regarding of the biochemical activity of dissolved organic matter. It may be that the weak responses of whole communities to browning are masked because the individual mitigating strategies of community components have disparate demographic consequences

Freshwater reservoirs play a significant role in the global carbon cycle by processing and storing large quantities of dissolved organic matter (DOM). Quantifying the magnitude of DOM fluctuations across multiple temporal scales can advance our understanding of how the controls on reservoir carbon cycling may vary. We monitored fluorescent DOM (fDOM) using an in situ epilimnetic sensor at a ten-minute

Wetlands and ditches are both common aquatic habitats in lowland landscapes of northeast China. However, most biodiversity management and research for aquatic organisms has focused on the biota of natural wetlands, and the invertebrate fauna of ditches has not been previously addressed. Because ditch habitats can be so extensive in some landscapes, their contribution could be substantial. To assess

The role of trace metal micronutrients in limiting cyanobacterial growth and structuring the phytoplankton community is becoming more evident. However, little is known regarding the extent of micronutrient limitation in freshwaters or which micronutrient conditions favour potentially-toxic cyanobacteria. To assess how freshwater phytoplankton respond to micronutrient and macronutrient additions, we

Beta-diversity measures have been used to understand patterns of community distribution in natural ecosystems. Recent studies included different facets of beta-diversity analyses, e.g. trait- and phylogeny-based. Here, we used ostracod communities to evaluate the influence of environmental and spatial factors structuring different facets of beta-diversity and their components (Beta-total, replacement

Drying in alpine streams might decrease aquatic-terrestrial trophic linkages by reducing terrestrial predation on aquatic prey. We tested this hypothesis by investigating whether a common riparian predator (hunting spiders) in alpine environments assimilated a lower proportion of aquatic prey with increasing stream intermittency. We used high temporal-resolution data from electrical resistance sensors

Light and nutrients are bottom-up factors in controlling biofilm in tropical shaded oligotrophic streams. Regardless of the predominant resource source (autochthonous or allochthonous), greater availability of light and nutrients favors the development and, later, grazing (top-down factor) of the biofilm, with reflections on the trophic structure of these ecosystems. The increase in primary productivity

Flooding events in large rivers, termed flood pulses, expand and contract habitat available for fish populations, affecting fish abundance and catches. Here, we investigated if river hydrologic variability affected catch of curimatã (Prochilodus nigricans), a widely distributed and economically important fish species of the Amazon Basin. Using fish catch and fishing effort data for the lower Amazon

The grazing effects of zooplankton communities are predicted to be strongest in mesotrophic lakes relative to eutrophic and oligotrophic lakes, an idea known as the Mesotrophic Maximum Hypothesis. We tested if the predictions of this hypothesis depend on the community of zooplankton present by evaluating whether the community of zooplankton, in addition to lake trophic state, interact to determine

Dissolved organic carbon (DOC) impacts water quality, the carbon cycle, and the ecology of aquatic systems. Understanding what controls DOC is therefore critical for improving large-scale models and best management practices for aquatic ecosystems. The two main processes of DOC transformation and removal, photochemical and microbial DOC degradation, work in tandem to modify and remineralize DOC within

Lake browning—the increase in catchment-derived (allochthonous) dissolved organic matter (DOM) to lakes—is altering lake physicochemical environments, with consequences for phytoplankton biomass and community composition. We hypothesized that as lakes brown, there will be an increase in phytoplankton biomass and a shift to cyanobacteria-dominated phytoplankton communities as a result of the reduced

The alluvial valley of the Mississippi River is an extensive area harboring hundreds of lakes created by fluvial dynamics. These floodplain lakes are scattered throughout the valley and carved over thousands of years by shifting river courses and other hydro-fluvial processes associated with contemporary and prehistoric rivers. These lakes have significant ecological importance as they support a large

A pattern of increasing similarity among ecological communities in space or time is usually a consequence of anthropogenic pressures. However, natural causes such as flood pulse may also increase spatial similarity among lakes or temporal similarity within a lake. We assessed whether floods homogenize zooplankton and macrophyte assemblages in space and time using a 16 years data set obtained in six

Hydrological intermittency affects sediment biogeochemistry, organic carbon (OC) metabolism and carbon dioxide (CO 2 ) emission but the study of the effects of drying is generally confined to natural ecosystems. Agricultural canals are artificial, widespread elements in irrigated floodplains, and regularly subjected to water level fluctuations. The aim of this study was to quantify the CO 2 emissions

Sea surface temperature fronts in the Northeastern Arabian Sea (NEAS) facilitate nutrient enhancement in the surface layers, resulting in high primary production. Such high production areas contribute to the accumulation of fresh organic matter rich in carbohydrates, thereby supporting higher heterotrophic metabolism. Transparent exopolysaccharides (TEP) are one of the carbohydrate polymers released

Water quality degradation is one of the largest threats to freshwater ecosystems. Nutrient inputs, land use changes, and climate are expected to be the most important drivers of water quality degradation. Here, we quantify the relative influence of nutrient inputs, climate, and lake geomorphometry on primary production in freshwater lakes globally, using chlorophyll a (chla) as a proxy. We used a large

As fatty acids are one of the most crucial biomolecules transferred across the aquatic food webs, they are claimed to be bioindicators of stressors. Among the various environmental stressors, food shortage is of prime importance. Lower food availability can affect fatty acid metabolism of organisms. We investigated the effects of short-term starvation on fatty acid metabolism of Daphnia magna neonates

Submerged macrophytes are key components of shallow lake biological communities, and their presence has been associated with a predominantly clear-water state. Conversely, lakes lacking macrophytes are often turbid with elevated phytoplankton abundance. One main mechanism that influences the presence or absence of submerged macrophytes is turbidity that reduces the light available to macrophytes. Increases

Inputs of glacial meltwater and changes in climate can profoundly influence lake ecosystems. Anderson and Seton lakes, two morphologically and chemically similar fjord lakes within the Fraser River Basin, British Columbia, experience a common biogeoclimatic setting, yet contrasting turbid-water influences from a hydroelectric development which diverts glacially-turbid water into Seton Lake, but not

Aquatic macrophytes increase habitat complexity and influence the structure of fish communities. We investigated relations between macrophyte stand complexity and functional alpha and beta diversity of fish. We sampled fish and plants in 30 macrophyte stands with differences in density and diversity in the Paraná River floodplain. The functional alpha diversity, measured as functional richness index

In many lowland streams, macrophytes are highly abundant and play a key role in ecosystem structure and function. However, no studies on annual stream metabolism have been conducted in streams with significant macrophyte abundance, despite the well-known effect on both gross primary production (GPP) and ecosystem respiration (ER). Macrophyte abundance in temperate streams is strongly seasonal, with

Cootes Paradise Marsh (CP) is an urban wetland and is part of the Hamilton Harbour Area of Concern (AOC). Anthropogenic stressors have degraded the system’s water quality. Submerged aquatic vegetation (SAV) provides critical fish habitat, and its recovery is crucial to this AOC’s delisting efforts. We developed predictive models to recommend water clarity (Secchi depth) targets that can potentially

We evaluated temporal trends in zooplankton functional diversity (functional richness—FRic, evenness—FEve divergence—FDiv, and Community-Weighted Means—CWM) in 12 habitats of the Upper Parana River floodplain (Brazil) over 16 years (2000–2016) and their relationships with environmental predictors (chlorophyll-a, water depth, and turbidity). We hypothesized that different environmental drivers affect

We investigated the effects of seawater warming and CO2 enrichment on the microbial community metabolism (using O2 consumption as a proxy) in subtidal silt sediment. Intact sediment cores, without large dwelling infauna, were incubated for 24 days at 12 (in situ) and 18 °C to confirm the expected temperature response. We then enriched the seawater overlying a subset of cold and warm-incubated cores

Phosphorus (P) enrichment of headwater agricultural streams due to the runoff of fertilizers can lead to the eutrophication of downstream aquatic ecosystems. Agriculture is intensive but heterogeneous in the Mississippi River Basin, with a mixture of pasture, row crops, and patches of confined animal feedlot operations (CAFOs). Many studies have evaluated how a single form of agricultural land use

The complex environments and climatic conditions of the Qinghai-Tibet Plateau (QTP) create unique patterns of species diversity. However, the effect of uplift of the QTP on the distribution of Gymnocypris species (Gymnocypris) remain unclear. We found that the Qilian Mountain (QL) population has the highest genetic diversity by mitochondrial DNA hypervariable region of Gymnocypris species, the Tibetan

Freshwater ecosystems worldwide are facing the establishment of non-native species, which, in certain cases, exhibit invasive characteristics. The impacts of invaders on native communities are often detrimental, yet, the number and spread of non-native invasive species is increasing. This is resulting in novel and often unexpected combinations of non-native and native species in natural communities

The activity level-predation risk paradigm of community assembly is based on observable trade-offs between activity level and predation risk. Many species that live in ephemeral habitats are relatively more active, grow faster, and metamorphose sooner than those in more permanent habitats, thus enabling them to survive by escaping drying ponds. Species with high activity levels are shown to be superior

Here we analysed the taxonomic and functional diversity of microcrustaceans along a horizontal gradient from the littoral to pelagic zones of a marginal lake. We hypothesized that in the littoral zone, occupied by high density of macrophytes, the taxonomic and functional diversity would be higher because the macrophytes coverage offers greater availability of niches for microcrustaceans. The individuals

Understanding how long-term environmental variation and biotic interaction determine biological assemblages is critical for evaluating the response of biological communities to anthropogenic and climate changes. We sampled plankton and water quality from a man-made lake monthly from 2006 to 2015 for the period from after creation to 13-year old of the lake. We used correlation, variation partitioning

Diversity at the local scale is determined by different, and often interacting factors. One factor that is suggested to be important in determining community structure is productivity, which is related to diversity. Though this relationship might depend on different factors, a hump-shaped, U-shaped or positive linear relationship seems to be frequent at the local scale. On the other hand, the concept

Dissolved oxygen (DO) concentrations in streams are driven by multiple, interacting biotic and abiotic processes. While DO variability largely reflect cyclic patterns of respiration and photosynthesis coupled to diel cycles, physical processes such as floods that disturb biofilms and variation in temperature disrupt such cycles. In urban settings, DO cycles are typically greatly altered by elevating

Water level fluctuations (WLF), one of the most affected ecological drivers by climate change, are dominant forces controlling submerged macrophyte performance and distribution in freshwater ecosystems. Submerged macrophytes are prominent components of shallow lakes, predicting their response to WLF is therefore crucial for the management and conservation of these valuable and vulnerable ecosystems

Although aquaculture provides a stable and high-quality source of food, the environmental effects related to large-scale industrial aquacultural activities have raised concern. To identify the influence of aquacultural activities on sedimentary bacterial communities, we collected surface and deeper sediments from a series of sites subjected to varying intensities of aquacultural activities within Eastern

Growth of submerged and emergent macrophytes was studied together with heterotrophic bacterioplankton abundance and production in two Hungarian shallow lakes with dominant macrophyte covers. It was expected that bacterioplankton numbers and activity would have an effect on macrophyte biomass accumulation. Bacterial production and abundance showed a strong seasonal pattern with maximum in the warmest

Lepidurus arcticus (the Arctic tadpole shrimp) is a vulnerable keystone species in Arctic and alpine water bodies where its occurrence and population size may influence the viability and life history traits of resident salmonids. Using data from a Norwegian mountain hydropower reservoir, Aursjoen, we illustrate how reduced availability of L. arcticus as prey resulted in the reduced condition, growth

Freshwater bivalves can influence water quality by reducing phytoplankton levels through filter-feeding and altering nutrient levels through excretion and biodeposition. In northeast Australia, native freshwater bivalves (Corbicula australis) may help restore the water quality of coastal wetlands that receive high nutrient loads in runoff from nearby agricultural activity. We investigated the biofiltration