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

The emission of CO2 and CH4 by diffusion, bubbling and downstream was measured in ten reservoirs representative of the diversity of French hydropower reservoirs in 2016. In all reservoirs, higher fluxes were measured in summer than in spring and winter. Low fluxes were measured in alpine reservoirs as compared to run-of-the-river and storage reservoirs. The low temperatures as well as the low organic

We investigated which environmental variables of floodplain lakes act as potential drivers of fish assemblages and how they explain the variation in taxonomic and functional diversity of the community. We evaluated the taxonomic richness, functional dispersion (the distribution of species abundances with different traits) and redundancy (how similar the species are) of fish communities from six floodplain

Large quantities of material are moved annually from the ocean to freshwater systems by migrating Pacific salmon. Previous studies have focused on nitrogen and phosphorus provided by spawning salmon but largely ignored micronutrients essential to aquatic productivity. We collected salmon tissue, water, and biofilm from seven southeast Alaskan streams both before and during the salmon run to test for

The construction of drainage canals in the upper stretch of the Salado River has caused the input of salty waters into the basin, with unexplored consequences on zooplankton dynamics and reproduction. To determine the consequences of those anthropic interventions, zooplankton samples were taken under four hydrologic conditions (high water, mean flows, low flows, very low flows) in the canals and the

Terrestrial organic matter (OM) is an essential energy source that fuels many food webs. The factors contributing to OM decomposition and the rate at which OM decomposes can influence carbon fluxes through ecosystems. Previous research demonstrates that the factors driving OM decomposition can vary with environmental condition, prompting more research that characterizes the relative importance of each

Scaling relationships, including power laws, provide quantitative predictions used in basic and applied sciences. We investigated scaling relationships between catchment area and lake surface area, the ratio of which has important implications for terrestrial-aquatic linkages. Synthesizing evidence from 9 datasets from three continents, we show that there is an approximately linear relationship between

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This paper studies the influence of the impounding process during flood recession in the TGR on the distribution and rerelease of sediment phosphorus forms in the Xiangxi Bay in 2016. Influenced by the main stream of the Three Gorges Reservoir (TGR) flowing backward during impoundment, the water environmental conditions, sediment grain size and sediment-forming environment of the tributary bays change

Concentrations of dissolved organic carbon (DOC) have increased recently in many lakes at high latitudes in North America and Europe, but it is unclear what effect this will have on the identity of the limiting nutrient for phytoplankton [nitrogen (N) vs. phosphorus (P)]. Identifying the effect of changing DOC on phytoplankton nutrient limitation is complicated by spatial covariation between atmospheric

Our understanding of how ecosystems function has changed from an equilibria-based view to one that recognizes the dynamic, fluctuating, nonlinear nature of aquatic systems. This current understanding requires that we manage systems for resilience. In this review, we examine how resilience has been defined, measured and applied in aquatic systems, and more broadly, in the socioecological systems in

Beta diversity can be analysed using various approaches, but those integrating site and species contributions to beta diversity are rare in floodplain lake systems. We analysed the beta diversity of rotifers and cladocerans across 50 floodplain lakes in Brazil, focusing on both pelagic and littoral zones. We partitioned beta diversity into local contributions (LCBD), species contributions (SCBD), and

Small headwater streams interlink catchment soils with the river network. As water makes its way from the hillslopes to the stream, it may transport dissolved organic carbon (DOC) and potentially soil microbes into stream water. In this study, we aimed at quantifying the dynamic transfer of DOC and microbial life, namely bacteria from catchment soils into streams. We hypothesized that increased soil

Changes in land cover are one of the most extensive and influential human impacts on fluvial ecosystems. In this study, we assessed how changes in food resource quantity and type linked to forest cover affect mountain stream multitrophic macroinvertebrate community size structure. We tested whether the total organism biomass (size spectrum intercept) and the energy transfer efficiency among trophic

Extreme drying can dramatically shift abiotic characteristics of streams and species respond differently as conditions change. We modified a conceptual model describing responses of aquatic invertebrate assemblages to stream drying to facilitate predictions of fish assemblage shifts in which thresholds of physiochemical gradients lead to punctuated losses of fish diversity as stream connectivity diminishes

Elevational gradients are ideal ecological venues for testing how communities respond to environmental changes associated with global warming. Recent warming rates have been shown to increase with elevation, hypothetically translating into heat waves that more adversely affect cold-adapted alpine communities than lower montane communities exposed to cold waves. We tested this hypothesis by conducting

We investigated whether environmental filtering or dispersal-related factors mostly drive helophyte and hydrophyte species richness and community composition in 93 lakes situated in Baikal Siberia. Using partial linear regression and partial redundancy analysis, we studied (1) what are the relative roles of environmental variables, dispersal variables, spatial processes and region identity (i.e., river

In calcareous watersheds, groundwater alkalinity results largely from dissolution of carbonate minerals in soils. The alkalinity increases initially approximately in proportion to nitrate (NO3−) concentration and eventually approaches an apparent maximum of approximately 8 mmol L−1 at high NO3− concentrations. This close positive relationship between alkalinity and NO3− concentration appears to be

Channelization can have far-reaching and long-term impacts on stream ecology. In this study, we demonstrate that channelization is associated with lower stream quality as measured by macroinvertebrate bioindicators when compared to unchannelized streams. Citizen scientists collected the data for this study between 1995 and 2014, performing 3021 sampling events during the months of May and June across

Trait-based approaches have been used to explore ecosystem level consequences of local changes in biodiversity along environmental gradients. Using a novel response–effect trait framework, we seek to identify and explain the mechanisms governing the cascading effects of environment on plant traits and ecosystem multi-functioning in the large Poyang Lake wetland, China. We sampled the above-ground biomass