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  1. Article ; Online: Diatom and Macroinvertebrate assemblages to inform management of Brazilian savanna’s watersheds

    Camila Aida Campos / Mark J. Kennard / José Francisco Gonçalves Júnior

    Ecological Indicators, Vol 128, Iss , Pp 107834- (2021)

    2021  

    Abstract: Human activities are increasingly affecting freshwater ecosystems and biodiversity, especially in neotropical regions like the Brazilian savanna. Limited research and data availability have inhibited the development and implementation of systematic ... ...

    Abstract Human activities are increasingly affecting freshwater ecosystems and biodiversity, especially in neotropical regions like the Brazilian savanna. Limited research and data availability have inhibited the development and implementation of systematic bioassessment programs and management guidelines. Identifying drivers of biological assemblages’ composition and ecological thresholds along human disturbance gradients is an important step to protect and recover freshwater ecosystems while avoiding threats to biodiversity, goods and services of value to humans. The objectives of this study were to: 1) assess changes in the composition and density of periphytic diatom and macroinvertebrate assemblages relative to natural and human disturbance gradients in Brazilian savanna’s streams, and 2) identify ecological thresholds for direct and indirect human disturbances and potential indicator taxa that could inform the development of biomonitoring programs in Brazil and other neotropical countries. Samplings were carried out in 52 stretches of streams located in central Brazil during two campaigns throughout 2018. Ordination analyses (NMDS) were applied to identify the main drivers of biological assemblages' composition and analyses of taxa distribution in disturbance gradients (TITAN) were carried out to detect possible thresholds and potential bioindicator taxa. Our results pointed out that the scale of land use in the catchment, treated sewage input, and water quality variables (nitrate, phosphate, and conductivity) were the main drivers of diatom and macroinvertebrate assemblages. Taxa such as Eunotia (diatoms) and some families of the orders Ephemeroptera, Plecoptera, and Trichoptera (EPT, macroinvertebrates) were associated with natural conditions, while Nitzschia palea and Gomphonema (diatoms) and Oligochaeta and Hirudinea (macroinvertebrates) were related to environments with a higher degree of disturbance. Although ecological thresholds along disturbance gradients varied among taxa and biotic groups, our results ...
    Keywords Diatoms ; Macroinvertebrates ; Gradients ; Human disturbances ; Ecological thresholds ; Environmental assessment ; Ecology ; QH540-549.5
    Subject code 333
    Language English
    Publishing date 2021-09-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Setting thresholds of ecosystem structure and function to protect streams of the Brazilian savanna

    Camila Aida Campos / Alan M. Tonin / Mark J. Kennard / José Francisco Gonçalves Júnior

    Frontiers in Environmental Science, Vol

    2022  Volume 10

    Abstract: Freshwater environments are among the most threatened by human activities, consequently, their ecosystem structures and functions are targets of significant transformations. It makes monitoring an essential tool in the management of these environments. ... ...

    Abstract Freshwater environments are among the most threatened by human activities, consequently, their ecosystem structures and functions are targets of significant transformations. It makes monitoring an essential tool in the management of these environments. Ecological metrics have been proven to be effective in monitoring programs aimed at assessing freshwater ecosystem integrity. Structural and functional aspects of the ecosystem may allow for a comprehensive view of the multiple human impacts that occur at different scales. However, a gap in the effective use of such ecological tools lies in the identification of the relative importance of different mechanisms that cause impacts and the interactions between them. Using Boosted Regression Tree (BRT) models, we evaluated the relative importance of natural and human impact factors, from local to catchment scales, on metrics related to diatom and macroinvertebrate assemblages and ecosystem processes. The study was carried out in 52 stream reaches of the Brazilian savanna in central Brazil. Conductivity was the most relevant factor to explain the variation of ecological metrics. In general, macroinvertebrate metrics and algal biomass production responded to both water quality and land use factors, while metrics of diatoms and microbial biomass responded more strongly to water quality variables. The nonlinear responses allowed the detection of gradual or abrupt-changes curves, indicating potential thresholds of important drivers, like conductivity (100–200 µS cm−1), phosphate (0.5 mg L−1) and catchment-scale urbanization (10–20%). Considering the best performance models and the ability to respond rather to stress than to natural factors, the potential bioindicators identified in the study area were the macroinvertebrates abundance, the percentage of group Ephemeroptera/Plecoptera/Trichoptera abundance, the percentage of group Oligochaeta/Hirudinea abundance, the percentage of genus Eunotia abundance, the Trophic Diatom Index and the algal biomass production. The results ...
    Keywords ecosystem integrity ; boosted regression tree ; ecological metrics ; freshwater management ; monitoring programs ; Environmental sciences ; GE1-350
    Subject code 551
    Language English
    Publishing date 2022-08-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: New integrated hydrologic approach for the assessment of rivers environmental flows into the Urmia Lake

    Ali Mobadersani / Ali Hosseinzadeh Dalir / Mehdi Yasi / Hadi Arvanaghi / Mark J. Kennard

    Scientific Reports, Vol 12, Iss 1, Pp 1-

    2022  Volume 18

    Abstract: Abstract Recent research has greatly focused on the environmental water supplement of rivers individually and independently. However, a comprehensive and integrated view of all rivers in the basin is simultaneously required in closed basins leading to ... ...

    Abstract Abstract Recent research has greatly focused on the environmental water supplement of rivers individually and independently. However, a comprehensive and integrated view of all rivers in the basin is simultaneously required in closed basins leading to lakes and wetlands. This has affected Lake Urmia, which is the second largest saltwater lake in the world. It has been in danger of drying up in recent years as a result of not allocating the required environmental flow (e-flow) due to the increase in water resource consumption in the agricultural sector and climate changes. In this study, a method derived from the flow duration curve shifting (FDCS) method is presented in addition to explaining the possibility of providing the e-flow of rivers leading to the lake. The method can make the least amount of change in the hydrological characteristics of rivers while providing the volume of required water by the ecosystem of lakes or downstream wetlands. Unlike the conventional method which presents the results on a monthly basis, the above-mentioned method is based on daily data of hydrometric stations and can calculate the amount of the environmental requirement of rivers in real-time according to the upstream inlet of the river. This method has been used in the Urmia Lake basin. According to the results, it can provide the environmental requirement of the lake by allocating 70.5% of the annual flow of rivers and thus can save the lake and the ecosystem of the region from the current critical conditions.
    Keywords Medicine ; R ; Science ; Q
    Subject code 333
    Language English
    Publishing date 2022-05-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: The importance of groundwater for riverine fish faunas in a region of shale gas development in northern Australia

    Jenny Davis / Erica A. Garcia / Karen S. Gibb / Mark J. Kennard / Alea Rose / Nicola Stromsoe / Dion Wedd

    Frontiers in Environmental Science, Vol

    2023  Volume 11

    Abstract: Northern Australia contains the continent’s largest number of intact river systems, but these are facing increasing pressure as the proposed development of multiple and large-scale industries, including onshore gas, mining, horticulture, and agriculture, ...

    Abstract Northern Australia contains the continent’s largest number of intact river systems, but these are facing increasing pressure as the proposed development of multiple and large-scale industries, including onshore gas, mining, horticulture, and agriculture, accelerates. These developments will require the diversion or extraction of large amounts of water and increase the risk of contamination by industrial and agricultural chemicals. There is an urgent need to collect baseline biophysical information on these aquatic systems before major developments proceed. Much community concern has been expressed about the potential environmental impacts of a developing shale gas industry (fracking) in the Beetaloo Sub-basin and upper Roper River region of the Northern Territory. Here we describe the first major survey of the freshwater fish fauna of this region and an assessment of the importance of groundwater in supporting fish biodiversity. This region is remote from major human settlements and the waterbodies are often difficult to access. Accordingly, we maximised the information we collected from limited sampling sessions by using both traditional fish survey methods (netting and electrofishing) and eDNA analysis of water and benthic sediment samples. Water column eDNA doubled the number of species recorded to those obtained from traditional survey methods alone. We found that the fish fauna was richest at sites on northward-flowing groundwater-dependent rivers. More work is needed to fully understand the dependence of individual species on groundwater inflows. However, it is evident that conserving freshwater fish biodiversity in these rivers will require protection of the groundwater resources to ensure baseflows and aquatic refuges persist through the most extended of dry seasons.
    Keywords baseline environmental surveys ; groundwater-dependent ; aquatic refuges ; eDNA ; baseflows ; Environmental sciences ; GE1-350
    Subject code 333
    Language English
    Publishing date 2023-05-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: The influence of landscape at multiple spatial scales of the river basins at the Eastern Amazon fish assemblage

    Thiely O. Garcia / Naraiana L. Benone / Bruno S. Prudente / Naiara R. Torres / Stuart E. Bunn / Mark J. Kennard / Luciano F. A. Montag

    Neotropical Ichthyology, Vol 21, Iss

    2023  Volume 2

    Abstract: Abstract The Amazon River basins present distinct natural and anthropogenic characteristics that influence the structure of stream habitats and their associated biota. The influence of these characteristics can be evaluated through different spatial ... ...

    Abstract Abstract The Amazon River basins present distinct natural and anthropogenic characteristics that influence the structure of stream habitats and their associated biota. The influence of these characteristics can be evaluated through different spatial scales. We aimed to assess the influence (with and without the effect of spatial-geographical factors) of local, macroscale, and land-use variables in the structure of stream fish assemblages of Amazonian catchments with different deforestation levels. A partial redundancy analysis and a reduced metrics model were used to assess these influences. With geographic-spatial effects, we verified that the macroscale and local variables explained the variation in fish composition, and, without the effects, land use also explained the variation in this composition. In the forested catchments, the biota was associated with streams with natural characteristics (e.g., leaf banks). In the deforested catchments, it was associated with land use, sandy catchments with higher soil density (higher capacity of degradation), and less complex streams (fewer leaf banks, more sand). The associated fish have life features linked to these characteristics (e.g., Gymnorhamphichthys rondoni associated with sand). This configuration seems to be a result of both the impact of land use in the catchment (i.e., increased erosion, increased sedimentation) and the naturally sandy constitution of the catchment as well, reflecting the sandy substrate.
    Keywords Conservation ; Degradation ; Land use ; Soil density and spatial scale ; Zoology ; QL1-991
    Subject code 550
    Language English
    Publishing date 2023-07-01T00:00:00Z
    Publisher Sociedade Brasileira de Ictiologia
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Assessing Changes in Terrestrial Water Storage Components over the Great Artesian Basin Using Satellite Observations

    Pankaj R. Kaushik / Christopher E. Ndehedehe / Ryan M. Burrows / Mark R. Noll / Mark J. Kennard

    Remote Sensing, Vol 13, Iss 4458, p

    2021  Volume 4458

    Abstract: The influence of climate change and anthropogenic activities (e.g., water withdrawals) on groundwater basins has gained attention recently across the globe. However, the understanding of hydrological stores (e.g., groundwater storage) in one of the ... ...

    Abstract The influence of climate change and anthropogenic activities (e.g., water withdrawals) on groundwater basins has gained attention recently across the globe. However, the understanding of hydrological stores (e.g., groundwater storage) in one of the largest and deepest artesian basins, the Great Artesian Basin (GAB) is limited due to the poor distribution of groundwater monitoring bores. In this study, Gravity Recovery and Climate Experiment (GRACE) satellite and ancillary data from observations and models (soil moisture, rainfall, and evapotranspiration (ET)) were used to assess changes in terrestrial water storage and groundwater storage (GWS) variations across the GAB and its sub-basins (Carpentaria, Surat, Western Eromanga, and Central Eromanga). Results show that there is strong relationship of GWS variation with rainfall (r = 0.9) and ET (r = 0.9 to 1) in the Surat and some parts of the Carpentaria sub-basin in the GAB (2002–2017). Using multi-variate methods, we found that variation in GWS is primarily driven by rainfall in the Carpentaria sub-basin. While changes in rainfall account for much of the observed spatio-temporal distribution of water storage changes in Carpentaria and some parts of the Surat sub-basin (r = 0.90 at 0–2 months lag), the relationship of GWS with rainfall and ET in Central Eromanga sub-basin (r = 0.10–0.30 at more than 12 months lag) suggest the effects of human water extraction in the GAB.
    Keywords Great Artesian Basin ; groundwater storage variation ; GRACE ; PCA ; MLRA ; rainfall ; Science ; Q
    Subject code 550
    Language English
    Publishing date 2021-11-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article: Depth-related composition and structuring of tropical riverine fish assemblages revealed by baited video

    Cousins, Stephen / Mark J. Kennard / Brendan C. Ebner

    Marine & freshwater research. 2017, v. 68, no. 10

    2017  

    Abstract: The aim of the present study was to determine whether boat-based deployment of remote underwater video cameras is effective for surveying fish assemblages in the deepest reaches of two large tropical rivers in north-eastern Australia. In addition, we ... ...

    Abstract The aim of the present study was to determine whether boat-based deployment of remote underwater video cameras is effective for surveying fish assemblages in the deepest reaches of two large tropical rivers in north-eastern Australia. In addition, we compared fish assemblages recorded on baited versus unbaited cameras, and evaluated the sampling effort (duration of recording) required to estimate fish assemblages using remote underwater videos. We found that fish assemblages differed according to the depth, with statistically significant differences largely attributable to the prevalence of small-bodied species (<10-cm total length, TL), such as Ambassis sp., Melanotaenia sp. and Pseudomugil signifer recorded in shallow (0.4–2.0m) and intermediate (2.1–4.9m) depths, and larger-bodied fish species (>10cm TL), such as Lutjanus argentimaculatus, Mesopristes argenteus and Caranx sexfasciatus, in deep water (>5.0m). Estimates of fish assemblage attributes generally stabilised after 60min recording duration, suggesting that interrogation of video footage beyond this duration may not be cost-effective. We conclude that depth is an important consideration when surveying large and deep river fish assemblages and that where water clarity is favourable, underwater video provides one of the means by which an assemblage can be investigated across the entire depth profile.
    Keywords Caranx ; Lutjanus argentimaculatus ; Melanotaenia ; Pseudomugil signifer ; cost effectiveness ; fish ; rivers ; surveys ; video cameras ; water quality ; Australia
    Language English
    Size p. 1965-1975.
    Publishing place CSIRO Publishing
    Document type Article
    ZDB-ID 1283028-8
    ISSN 1323-1650
    ISSN 1323-1650
    DOI 10.1071/MF16278
    Database NAL-Catalogue (AGRICOLA)

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  8. Article ; Online: Effects of a low-head weir on multi-scaled movement and behavior of three riverine fish species

    Luke Carpenter-Bundhoo / Gavin L. Butler / Nick R. Bond / Stuart E. Bunn / Ivars V. Reinfelds / Mark J. Kennard

    Scientific Reports, Vol 10, Iss 1, Pp 1-

    2020  Volume 14

    Abstract: Abstract Despite providing considerable benefits to society, dams and weirs threaten riverine ecosystems by disrupting movement and migration of aquatic animals and degrading riverine habitats. Whilst the ecological impacts of large dams are well studied, ...

    Abstract Abstract Despite providing considerable benefits to society, dams and weirs threaten riverine ecosystems by disrupting movement and migration of aquatic animals and degrading riverine habitats. Whilst the ecological impacts of large dams are well studied, the ecological effects of low-head weirs that are periodically drowned out by high flows are less well-understood. Here we examine the effects of a low-head weir on fine- and broad-scale movements, habitat use, and breeding behaviour of three species of native freshwater fish in the Nymboida River in coastal eastern Australia. Acoustic telemetry revealed that eastern freshwater cod (Maccullochella ikei) and eel-tailed catfish (Tandanus tandanus) made few large-scale movements, but Australian bass (Percalates novemaculeata) upstream of the weir were significantly more mobile than those below the weir. Within the weir pool, all three species displayed distinctive patterns in fine-scale movement behaviour that were likely related the deeper lentic environment created by the weir. No individuals of any species crossed the weir during the study period. Tandanus tandanus nesting behaviour varied greatly above and below the weir, where individuals in the more lentic upstream environment nested in potentially sub-optimal habitats. Our results demonstrate the potential effects of low-head weirs on movement and behaviour of freshwater fishes.
    Keywords Medicine ; R ; Science ; Q
    Subject code 590
    Language English
    Publishing date 2020-04-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article: Catchment zoning to enhance co‐benefits and minimize trade‐offs between ecosystem services and freshwater biodiversity conservation

    Hermoso, Virgilio / Lorenzo Cattarino / Mark J. Kennard / Simon Linke

    Aquatic conservation. 2018 Aug., v. 28, no. 4

    2018  

    Abstract: Integrating ecosystem services (ESs) in landscape planning can help to identify conservation opportunities by finding co‐benefits between biodiversity conservation and the maintenance of regulating and cultural ecosystem services. The adequate ... ...

    Abstract Integrating ecosystem services (ESs) in landscape planning can help to identify conservation opportunities by finding co‐benefits between biodiversity conservation and the maintenance of regulating and cultural ecosystem services. The adequate integration of ESs needs careful consideration of potential trade‐offs, however, especially between provisioning services and biodiversity conservation (e.g. the potentially negative consequences of agricultural water extraction within areas important for the maintenance of biodiversity). These trade‐offs have been overlooked in systematic spatial planning to date, especially in freshwater systems. marxan with zones was used to identify priority areas for the conservation of freshwater biodiversity (139 species of freshwater fish, turtles, and waterbirds) and the provision of freshwater ESs in the Daly River, northern Australia. Four different surrogates for ESs were mapped, including those potentially incompatible with conservation goals (i.e. groundwater provision for agriculture and recreational fisheries) and those that are more compatible with conservation (i.e. flood regulation by riparian forests; provision of perennial water). The spatial allocation of multiple management zones was prioritized: (i) three conservation zones, aiming to represent freshwater biodiversity and compatible ESs to enhance co‐benefits; and (ii) two production zones, where access to provisioning ESs could be granted. The representation of ESs obtained when using the multi‐zoning approach was compared with that achieved with a single management zone approach. The comparison was performed across different representation targets. Different results were found with low and high targets for ESs. With low targets (<25% of all ESs), the multi‐zoning approach achieved up to 53% more co‐benefits than the single‐zone approach. With high targets (>25% of all ESs), the trade‐offs avoided were more evident, with up to 56% less representation of incompatible ESs within conservation zones. Multi‐zone planning could help decision makers respond better to the increasingly complex catchment management context, caused by an increasing demand for provisioning services and a diminishing availability of resources, as well as manage and plan for challenges in other realms facing similar problems.
    Keywords biodiversity ; biodiversity conservation ; decision making ; ecosystem services ; freshwater ; groundwater ; landscapes ; planning ; riparian forests ; rivers ; sport fishing ; turtles ; water birds ; watershed management ; watersheds ; zoning ; Australia
    Language English
    Dates of publication 2018-08
    Size p. 1004-1014.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 1146285-1
    ISSN 1052-7613
    ISSN 1052-7613
    DOI 10.1002/aqc.2891
    Database NAL-Catalogue (AGRICOLA)

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  10. Article: Fish assemblage dynamics in an intermittent river of the northern Australian wet–dry tropics

    Pusey, Bradley J / Mark J. Kennard / Michael Douglas / Quentin Allsop

    Ecology of freshwater fish. 2018 Jan., v. 27, no. 1

    2018  

    Abstract: Intermittent rivers make up a large portion of the global river network and are the dominant river type in northern Australia. Increased pressure is being placed on such systems, and a better understanding of their ecology is needed. We examined, over a ... ...

    Abstract Intermittent rivers make up a large portion of the global river network and are the dominant river type in northern Australia. Increased pressure is being placed on such systems, and a better understanding of their ecology is needed. We examined, over a 7‐year period, the fish fauna of the intermittent Fergusson River, a major tributary of the Daly River of the northern Australia. Changes in habitat structure with the onset of the dry season involved contraction of the riffle/run/pool habitat to a single refugial pool, the size of which was determined by antecedent wet season hydrology. The fishes present comprised a subset of species present within the Daly River main channel and consisted of the most widely distributed of northern Australia's freshwater fishes. The Fergusson River provides suitable spawning habitat for species during the wet season (e.g. Hephaestus fuliginosus, Leiopotherapon unicolor and Neosilurus catfishes) and during the dry season for a different set of species (e.g. Amniataba percoides, Melanotaenia australis and Glossogobius aureus). Little year‐to‐year variation in assemblage structure was observed early in the dry season, whereas interannual variation in late dry season assemblages was substantial. Dry season recruitment imparted some of the interannual variability in assemblage structure recorded between late dry season samples. Piscivorous fishes were an important, but temporally variable, component of the assemblage present in the late dry season refugial habitat, and predation was potentially another important source of variation in assemblage structure.
    Keywords Amniataba ; Glossogobius ; Leiopotherapon ; Melanotaenia australis ; Neosilurus ; catfish ; dry season ; fauna ; freshwater fish ; habitats ; hydrology ; piscivores ; predation ; rivers ; spawning ; tropics ; wet season ; Australia
    Language English
    Dates of publication 2018-01
    Size p. 78-88.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 913011-1
    ISSN 0906-6691
    ISSN 0906-6691
    DOI 10.1111/eff.12325
    Database NAL-Catalogue (AGRICOLA)

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