Scientific Publications

This section gives the overview of scientific publications. Publications are listed in reversed chronological order, i.e. new ones appear on top.
For each publication you will find title, abstract, full reference and DOI.
Due to copy rights we are not allowed to make the full publication online available.
In case you wish to receive it then please contact the corresponding author by email.
Information for this can be found through the DOI.

Can macroinvertebrate biological traits indicate fine-grained sediment conditions in streams? (Murphy et al. 2017)

Excessive inputs of fine-grained sediment can damage aquatic ecosystems both by degrading habitat condition and by directly impairing biota. Recent research has improved our understanding of how benthic macroinvertebrates respond to fine-grained sediment stress, leading to the development of a variety of bioassessment indices based on changes in taxonomic composition and biological trait composition. Use of biological traits as indicators of stress has been advocated on the basis of a better mechanistic understanding of the biotic and abiotic factors acting on benthic communities. We quantified changes in the macroinvertebrate biological trait assemblage from a large number of river reaches spanning a national-scale gradient of increasing agricultural fine sediment delivery and retention, having first factored out variation associated with the natural environmental gradient, with the aim of robustly testing predictions of trait response.

Controls on anastomosis in lowland river systems: Towards process-based solutions to habitat conservation (Marcinkowski et al. 2017)

Anastomosing rivers were historically common around the world before extensive agricultural and industrial development in river valleys. Few lowland anastomosing rivers remain in temperate zones, and the protection of these river-floodplain systems is an international conservation priority. However, the mechanisms that drive the creation and maintenance of multiple channels, i.e. anabranches, are not well understood, particularly for lowland rivers, making it challenging to identify effective management strategies. This study uses a novel multi-scale, process-based hydro-geomorphological approach to investigate the natural and anthropogenic controls on anastomosis in lowland river reaches. Using a wide range of data (hydrologic, cartographic, remote-sensing, historical), the study (i) quantifies changes in the planform of the River Narew, Poland over the last 100 years, (ii) documents changes in the natural and anthropogenic factors that could be driving the geomorphic change, and (iii) develops a conceptual model of the controls of anastomosis.

Using historical data in fluvial geomorphology (Grabowski & Gurnell 2016)

This chapter addresses the range of sources that can be used to investigate changes in fluvial geomorphology; including documentary evidence, cartographic sources, topographic surveys and remotely sensed data. Documentary evidence serves two primary roles in the historical analysis of channel and catchment characteristics. The first is to extend analyses back in time prior to the collection of systematic survey data. The second is to corroborate observations or measurements from other sources or to serve as a temporal or spatial benchmark with which to gauge river change.

Dispersal capacity shapes responses of river island invertebrate assemblages to vegetation structure, island area, and flooding (Vanbergen et al 2017)

Riparian invertebrate communities occupy a dynamic ecotone where hydrogeomorphological (e.g. river flows) and ecological (e.g. succession) processes may govern assemblage structure by filtering species according to their traits (e.g. dispersal capacity, niche). We surveyed terrestrial invertebrate assemblages (millipedes, carabid beetles, spiders) in 28 river islands across four river catchments over 2 years.

We predicted that distinct ecological niches would produce taxon-specific responses of abundance and species richness to: (i) disturbance from episodic floods, (ii) island area, (iii) island vegetation structure, and (iv) landscape structure. We also predicted that responses would differ according to species’ dispersal ability (aerial vs. terrestrial only), indicating migration was sustaining community structure.

Using fuzzy cognitive maps for predicting river management responses: A case study of the Esla River basin, Spain (Solana-Gutiérrez et al 2017)

The planning and management of river ecosystems affects a variety of social groups (i.e., managers, stakeholders, professionals and users) who have different interests about water uses. To avoid conflicts and reach an environmentally sustainable management, various methods have been devised to enable the participation of these actors. Mathematical modelling of river systems is highly recommended to forecast, but we do not always have enough information to do it. In these cases, the soft and meta-models can be valid alternatives to simulate these complex systems. The Fuzzy Cognitive Maps (FCMs) are presented as a tool that facilitates the modelling of ecological systems, functions and services.

Modeling invasive alien plant species in river systems: Interaction with native ecosystem engineers and effects on hydro‐morphodynamic processes (van Oorschot et al 2017)

Invasive alien plant species negatively impact native plant communities by out-competing species or changing abiotic and biotic conditions in their introduced range. River systems are especially vulnerable to biological invasions, because waterways can function as invasion corridors. Understanding interactions of invasive and native species and their combined effects on river dynamics is essential for developing cost-effective management strategies. However, numerical models for simulating long-term effects of these processes are lacking. This paper investigates how an invasive alien plant species affects native riparian vegetation and hydro-morphodynamics. A morphodynamic model has been coupled to a dynamic vegetation model that predicts establishment, growth and mortality of riparian trees.

Riparian plant species preferences indicate diversification of site conditions after river restoration (Modrak et al 2017)

Numerous river restoration projects have been undertaken to improve the hydromorphology of rivers and their floodplains. Subsequent ecological monitoring is usually restricted to instream quality assessment, but riparian areas and floodplains are rarely assessed. A good indicator for riparian assessment could be vegetation as its diversity is dependent on functioning hydromorphological processes. We used a comparative survey to test the effect of newly created river morphological features on riparian plant composition at restored reaches relative to nonrestored reaches.

How much ecological integrity does a lake need? Managing the shores of a peri-urban lake (Lorenz et al 2017)

Physical modifications leading to a homogenization of previously diverse littoral habitats increasingly affect the ecological integrity of lake shores in urban landscapes. The European Water Framework Directive (EU WFD) requires integrative assessment of the ecological status of lake ecosystems including lake shore assessment aimed at reaching good ecological status (GES). The ecological consequences of lake shore modifications can be assessed site-specifically by ecological assessment tools based on benthic invertebrates in compliance with the EU WFD. However, it still remains unclear which percentage of the lake shore may be morphologically altered until whole-lake ecological status is affected. We studied a peri-urban lake with ∼50% of the shoreline altered by urban developments and recreational facilities and the other 50% still remaining in a near-natural, undeveloped state. We assessed the ecological status of each shore type using the Littoral Invertebrate Multimetric Index based on Composite Sampling (LIMCO).

The Environmental Costs of Water Flow Regulation: an Innovative Approach Based on the ‘Polluter Pays’ Principle (García de Jalón et al. 2017)

The EU Water Framework Directive (WFD) explicitly requires the full cost recovery of water services, including the environmental costs incurred from the damage that water uses inflict on the environment. Although flow regulation by river damming is one of the most prominent human impact on fresh water ecosystems its environmental costs are not properly included in water pricing. This paper presents a novel approach to assessing the environmental costs of flow regulation based on the polluter-pays principle.

Integrated planning framework for successful river restoration projects: upscaling lessons learnt from European case studies (Angelopoulos et al. 2017)

Despite considerable investment in river restoration projects, there is still limited information on the efficacy and success of river restoration activities. One of the main reasons is poor or improper project design, resulting in common problems such as: not addressing the root cause of habitat degradation; not establishing reference conditions, benchmarks and not defining endpoints against which to measure success; inappropriate uses of common restoration techniques because of lack of pre-planning; and inadequate monitoring or appraisal of restoration projects. In this paper peer-reviewed and grey literature and a large database of existing case studies were reviewed to identify the prevailing challenges river managers face when planning and developing river restoration projects. To overcome these current challenges an integrated project planning framework has been developed that incorporates adaptive management and project management techniques.

Hydromorphological restoration stimulates river ecosystem metabolism (Kupilas et al. 2017)

Both ecosystem structure and functioning determine ecosystem status and are important for the provision of goods and services to society. However, there is a paucity of research that couples functional measures with assessments of ecosystem structure. In mid-sized and large rivers, effects of restoration on key ecosystem processes, such as ecosystem metabolism, have rarely been addressed and remain poorly understood. We compared three reaches of the third-order, gravel-bed river Ruhr in Germany: two reaches restored with moderate (R1) and substantial effort (R2) and one upstream degraded reach (D). Hydromorphology, habitat composition, and hydrodynamics were assessed. We estimated gross primary production (GPP) and ecosystem respiration (ER) using the one-station open-channel diel dissolved oxygen change method over a 50-day period at the end of each reach.

Mechanistic modeling for predicting the effects of restoration, invasion and pollution on benthic invertebrate communities in rivers (Paillex et al. 2017)

Habitat destruction, biological invasions and water quality deterioration are serious threats to native communities and can lead to modifications in community composition and structure, and in ecosystem function. To predict the consequences of river restoration, biological invasions and water quality change in the taxonomic composition of macroinvertebrate communities in rivers, we extended the mechanistic model Streambugs, which describes growth, respiration and death of interacting taxa under given environmental

New tools for the hydromorphological assessment and monitoring of European streams (Rinaldi et al. 2016)

Hydromorphological stream assessment has significantly expanded over the last years, but a need has emerged from recent reviews for more comprehensive, process-based methods that consider the character and dynamics of the river with greater accuracy. With this as a focus, a series of hydromorphological tools have been developed and/or further extended in Europe within the context of the REFORM (REstoring rivers FOR effective catchment Management) project.

Characterising physical habitats and fluvial hydromorphology: A new system for the survey and classification of river geomorphic units (Belletti et al. 2017)

Geomorphic units are the elementary spatial physical features of the river mosaic at the reach scale that are nested within the overall hydromorphological structure of a river and its catchment. Geomorphic units also constitute the template of physical habitats for the biota. The assessment of river hydromorphological conditions is required by the European Water Framework Directive 2000/60 (WFD) for the classification and monitoring of water bodies and is useful for establishing links between their physical and biological conditions.

Public values and preference certainty for stream restoration in forested watersheds in Finland (Lehtoranta et al 2017)

Agriculture and forestry activities increase the deposition of fine sediments in river and streambeds, with negative consequences for biodiversity and stream ecosystem functioning. However, little is known about the economic value of headwater stream restoration and the associated improvement in ecosystem services. Here, we apply the contingent valuation method to assess the awareness, knowledge, and values held by different stakeholder groups regarding a change in the set of ecosystem services related to the restoration of sediment-stressed forest streams in a large boreal catchment. 

Habitat rehabilitation in urban waterways: the ecological potential of bank protection structures for benthic invertebrates (Weber et al. 2017)

Compensating for the adverse ecological impacts of waterway development and improving their ecological functioning to achieve good ecological potential (GEP) have become mandatory within the European Union (EU). The technical rehabilitation measures presented here aim to functionally minimize the hydraulic impacts of navigation on aquatic biota in highly urbanized waterways. Their ecological functioning and potential to enhance biodiversity locally was assessed by comparing their macro-invertebrate community composition with nearby non-restored sites. 

Response of fish communities in rivers subjected to a high sediment load (Valero et al. 2016)

Erosion and sediment yield are a significant problem in the Guadalquivir River basin. Such phenomena are largely driven by a land use devoted to intensive cultivation of olive trees, with a large socioeconomic influence in Andalusia. This sediment overload in rivers causes serious impacts on all fluvial ecosystem components. In this study we assess the chronic effect of sediment yield on fish communities at 104 river sites located in two different sub-catchments – the Bembézar and Guadajoz rivers – both with different lithological composition and erosion rates. Sediment yield was estimated using a semi-quantitative Factorial Score Model (FSM), developed specifically for Spanish rivers. The fish populations of both basins were evaluated in composition and abundances by the study of Fernández-Delgado et al., 2014. The influence of sediment yield on the fish community was analyzed using General Additive Models.

Responses of fish and invertebrates to floods and droughts in Europe (Piniewski et al. 2016)

Floods and droughts, two opposite natural components of streamflow regimes, are known to regulate population size and species diversity. Quantifiable measures of these disturbances and their subsequent ecological responses are needed to synthesize the knowledge on flow–ecosystem relationships. This study for the first time combines the systematic review approach used to collect evidence on the ecological responses to floods and droughts in Europe with the statistical methods used to quantify the extreme events severity. 

Environmental and spatial controls of taxonomic versus trait composition of stream biota (Göthe et al. 2016)

The spatial organisation of biotic communities derives from factors operating at a wide range of spatial and temporal scales. Despite strong scientific evidence of prevalent spatial control of community composition in freshwater ecosystems, local environmental factors are often considered as the main drivers of community change. Furthermore, taxonomic approaches are most frequently used, and few studies have compared the relative importance of local and regional control of trait versus the taxonomic composition in stream ecosystems.

Using a spatially dense data set covering all stream sizes in a lowland European region of c. 42 000 km2 and three organism groups (macrophytes, macroinvertebrates and fishes), we compared the relative importance of spatial and environmental determinants of species and trait composition in the study streams, classified into headwaters (stream order 1–2) and downstream sites (stream order >2).

Linking environmental flows to sediment dynamics (García de Jalón et al 2016)

This is a policy discussion paper aimed at addressing possible alternative approaches for environmental flows (e-Flows) assessment and identification within the context of best strategies for fluvial restoration. We focus on dammed rivers in Mediterranean regions. Fluvial species and their ecological integrity are the result of their evolutionary adaptation to river habitats. Flowing water is the main driver for development and maintenance of these habitats, which is why e-Flows are needed where societal demands are depleting water resources. Fluvial habitats are also shaped by the combined interaction of water, sediments, woody/organic material, and riparian vegetation. 

Effective restoration of aquatic ecosystems: scaling the barriers (Friberg et al 2016)

The focus of ecosystem restoration has recently shifted from pure rehabilitation objectives to both improving ecological functioning and the delivery of ecosystem services. However, these different targets need to be integrated to create a unified, synergistic, and balanced restoration approach. This should be done by combining state-of-the-art knowledge from natural and social sciences to create manageable units of restoration that consider both the temporal and multiple spatial scales of ecosystems, legislative units, and policy agendas. 

A new paradigm for biomonitoring: an example building on the Danish Stream Plant Index (Baattrup-Pedersen et al 2016)

Despite intensive efforts for more than a decade to develop Water Framework-compliant assessment systems, shortcomings continue to appear. In particular, the lack of reference conditions has hindered the development of assessment systems capturing the heart of the Water Framework Directive (WFD) – that ecological status should be set as the deviation from the natural, undisturbed condition. Recently, the Danish Stream Plant Index (DSPI) was developed. This system contrasts existing systems in that it builds on an expert interpretation of the normative definitions of ecological status classes in the WFD without taking pressure–impact relationships into account.

Effective River Restoration in the 21st Century: From Trial and Error to Novel Evidence-Based Approaches (Friberg et al. 2016)

This paper is a comprehensive and updated overview of river restoration and covers all relevant aspects from drivers of restoration, linkages between hydromorphology and biota, the current restoration paradigm, effects of restorations to future directions and ways forward in the way we conduct river restoration. A large part of this paper is based on the outcomes of the REFORM (REstoring rivers FOR effective catchment Management, http://reformrivers.eu/) project that was funded by EU's 7th Framework Programme (2011–15). REFORM included the most comprehensive comparison, to date, of existing river restorations across Europe and their effect on biota, both in relation to preintervention state and project size in terms of river length restored. The REFORM project outcomes are supplemented by an extensive literature review and two case studies to illustrate key points. 

Evaluating good-practice cases for river restoration across Europe: context, methodological framework, selected results and recommendations (Muhar et al. 2016)

This introductory paper presents 20 river restoration cases throughout Europe that were investigated in the EU-funded research project REFORM. In the following, this special issue provides seven specific papers that highlight and discuss the effects of restoration on the investigated river–floodplain systems. Additionally, restoration success was estimated from a socio-economic perspective. 

Preface: Effects of hydromorphological river restoration—a comprehensive field investigation of 20 European projects (Kail et al. 2016)

All over Europe, river stretches are being restored to achieve “good ecological status” or “good ecological potential,” the targets of the EU Water Framework Directive. Hydromorphological restoration is one of the most frequently applied methods, including re-meandering, widening, and the re-connection of river and floodplain. Within the EU-funded project Restoring rivers FOR effective catchment Management (REFORM), an international team of scientists has addressed this question, by studying twenty restored river stretches in ten European catchments, always in comparison to a nearby non-restored stretch of the same river. Ten of the restored river sections represented a major restoration effort and a comparatively long restored river stretch, while the other ten restored sections were shorter. The special issue gives insight in the details of the study.

Pages