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 (CO2) 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 CO2 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 Paraná 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

AbstractLepidurus 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

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

Understanding how environmental factors and short-term evolution affect the growth of invasive plants is a central issue in Invasion Biology. For macrophytes, salinity is one of the main factors determining distribution along estuarine environments. Urochola arrecta is a Poaceae with high invasive potential in several freshwater and estuarine ecosystems. In South Brazilian estuaries, this species is

Cyanobacterial blooms aggravate with increasing temperature, and the increased concentrations of toxicants such as cyanotoxins and nitrite during bloom decay adversely affect the growth of aquatic animals. Heat-shock proteins (Hsps) are induced by a wide range of environmental stressors, including temperature and toxicants. In this study, Brachionus calyciflorus Pallas was exposed to different combined

Environmental filtering and dispersal limitation are essential processes affecting the variability of ecological communities. However, their relative contributions are highly debated and remain largely unknown in several systems, such as the hyperdiverse Amazon Basin. We determined the relative role of local, catchment, spatial, and biogeographical variables on the taxonomic and functional alpha and

Shoreline erosion in lakes is a pressing issue for many landowners, yet common erosion mitigation practices that involve armoring can alter littoral habitat and potentially diminish near-shore biodiversity. We studied the effects of two armoring methods (i.e., riprap, retaining walls) on habitat, taxonomic richness, relative abundance, and total abundance of fishes and benthic macroinvertebrates at

Temporally intensive observations of sediment biogeochemical fluxes were used to examine the effects of water column oxygen depletion and associated loss of sediment bioirrigation on denitrification rates. In the tidal Choptank River, a subestuary of the Chesapeake Bay, coupled nitrification/denitrification was identified as the main pathway for the production of N2 gas in the sediment. Although denitrification

Stream bacterial communities are shaped by a combination of local and regional processes, such as environmental filtering, biotic interactions and dispersal, but biotic interactions have received comparatively less attention. Here, we investigated stream bacterial alpha and beta diversity within taxonomic and phylogenetic contexts around Qiandao Lake in China. We further examined abiotic and biotic

AbstractOne debate about lake restoration is whether there is overemphasis of a “Phosphorus (P)-only” paradigm, while overlooking the limiting effect of nitrogen (N). In particular, the roles of internal nutrient cycling which could act as drivers of algal blooms are not yet well assessed. However, it is hardly possible to identify the complex mechanisms of nutrient limitation patterns in lakes only

Large wood is a key component of river channels that affects numerous hydrological, physical and geomorphological processes. It promotes a diversity of benthic habitats in-channel and has shown to support more abundant and diverse benthic macroinvertebrate assemblages in previous ecological studies. However, the effects of large wood on the structural and functional diversities of hyporheic invertebrates

The question of the efficient plot size for sampling vegetation has been discussed many times, but aquatic vegetation is rarely considered. Here we examine a dataset of aquatic (267) and littoral (456) vegetation samples from 60 sandpits across the Czech Republic to determine appropriate plot size while trying to maximise both efficiency and accuracy of the sampling effort. A dataset of littoral vegetation

The permeability of sediments at the sediment–water interface is an important control on several stream ecosystem services. It is well known that streambed permeability varies over several orders of magnitude, however, the environmental processes influencing this variation have received little attention. This review synthesizes the state-of-art knowledge and gaps in our understanding of the key physical

In urban stream networks, the headwaters are comprised of engineered headwaters where particulate organic matter collects during and between storms. During storms, dissolved organic matter leached from these pools is transported to the stream as stormflow connects these ephemeral channels to the network. Throughout the urban network, microbial processing consumes, produces, and transforms DOM, changing

Reservoir sediment is a major player in the terrestrial carbon (C) budget, and the quantification of C burial in sediments is important in assessing the reservoir’s role in the global C budget. However, assessments of C burial in sediments of sub-tropical hydroelectric reservoirs and their potential as C sinks are thus far limited due to a lack of whole reservoir assessments of C burial. In this study

Phytotelmata are habitats that house several species. Oftentimes invertebrate species need to disperse themselves sometimes carried by other animals, an interaction called phoresy. Phoresy can be influenced by different factors, therefore, we aim to investigate which factors influence the phoretic potential between anurans and invertebrates from bromeliads in semideciduous Atlantic Forest, as well

Determining where fish are distributed across days and seasons is valuable for understanding their ecology, evolution and conservation. The results presented here provide insight into the spatial and temporal distribution of brown trout (native salmonid species) and dace (invasive cyprinid species) in an artificially impounded section of lowland river, demonstrating that both species remain relatively

Trait variation across environmental gradients results from two processes: intraspecific variation (ITV) and turnover. Trait plasticity promotes intraspecific variation and can mediate, increasing or decreasing, interspecific variation. Here we evaluate patterns of ITV and trait-environment relationships in an anuran metacommunity from southern Brazil. We hypothesize that the contribution of ITV and

Like many wetlands globally, the Mulwaree River chain-of-ponds system exists in two dichotomous states characterised by the presence or absence of surface flow connecting large, deep, permanently inundated ponds. We develop a conceptual model of hydrological function of this chain-of-ponds system combining surface and subsurface water levels, 2H and 18O stable isotopes and 222Rn as a groundwater tracer

Through the artificial manipulation of hydrological residence time, hydropower operations on alpine lakes should not only alter their hydro-biogeochemical characteristics but also modulate the degree of sensitivity of the lake to atmospheric forcing. These hypotheses were addressed by means of in situ observations that were combined with a three-dimensional lake model of a high-altitude pump-storage

The oligotrophication of freshwater is the reduction of the nutrient concentration in the water column, which causes the depletion of organic matter and diminishes the biological production of the ecosystem. To elucidate the zooplankton response to nutrient depletion (oligotrophication), an experiment was performed in mesocosms simulating real scenarios. Phytoplankton and zooplankton inocula were collected

Continuous temperature monitoring for two adjacent tropical crater lakes in Mexico at 4200 m amsl shows that the lakes have rhythmic episodes of heating and cooling with a duration of ~ 30 days during the warmest months. The episodes were caused by rise and decline of solar irradiance reaching the lake surface. One lake, El Sol, showed over each heating and cooling episode a stable mixed layer (~ 20 days)

Deconstructing beta diversity patterns into site or species contributions is a modern approach to understand the factors affecting variation in biodiversity. In this context, estimating the Local Contribution to Beta Diversity (LCBD) and the individual Species Contribution to Beta diversity (SCBD) have been shown to be a good approach to improve knowledge of the drivers of beta diversity. We examined

In Lake Grande de Peñalara, an originally fishless small high mountain lake in the Central Iberian Peninsula, brook trout (Salvelinus fontinalis) was introduced in the 1970s, and then eradicated 30 years later using gillnets. In this study, we investigated the time-course and changes in macroinvertebrates and zooplankton communities, before and after the eradication, by studying their richness and

Shallow lake sediments may be anoxic despite overlying aerated water. In the current study, we aimed to ascertain the contribution of shallow areas to internal phosphorus (P) loading due to sediment anoxia in stratifying lakes. Moreover, we analyzed relationships of the key water quality variables with internal P loading due to sediment anoxia originating solely from stratifying areas (IPobs) and that

Estimating air–water gas transfer velocities (k) is integral to understand biogeochemical and ecological processes in aquatic systems. In lakes, k is commonly predicted using wind-based empirical models, however, their predictive performance under conditions that differ from their original calibration remains largely unassessed. Here, we collected 2222 published k estimates derived from various methods