- Email: [email protected]
Ecohydraulic case studies: Interdisciplinarity and technological evolutions
Limnologica 62 (2017) 140–141
Contents lists available at ScienceDirect
Limnologica journal homepage: www.elsevier.com/locate/limno
Editorial
Ecohydraulic case studies: Interdisciplinarity and technological evolutions
The articles in this Special Issue were presented at the 10th International Symposium on Ecohydraulics in Trondheim, Norway (2014), where the first symposium on ecohydraulics was organised 20 years before. The 10th issue of the symposium celebrated 20 years of ecohydraulic research and had about 300 delegates, giving 194 talks and presenting 86 posters. Over these 20 years, the field of ecohydraulics evolved from physical habitat simulations, mainly focusing on fish and rivers, to an interdisciplinary field of research linking biology, ecology, fluvial geomorphology, sediment transport, hydrology, fluvial hydraulics, river engineering and water resources. Technological evolutions allowed sophisticated data collection and processing, opening opportunities to address new topics like fish behaviour, species distribution modelling and microscale hydraulics. The articles in this special issue illustrate the diversity of ecohydraulic approaches: simulation models, field studies and laboratory or in situ experiments to investigate and analyse the complex relationships present in ecohydraulic problems, always linking to pragmatic management solutions. Since the last decades, advanced data analysis and modelling played a crucial role in selecting the optimal management options. In particular, the species distribution modelling of ecohydraulics shifted from univariate habitat preference curves to complex, multivariate and non-parametric species distribution modelling. This ˜ was illustrated by Munoz-Mas et al. (2017), who applied ensemble modelling techniques that combined different models to develop more robust and accurate models. The authors also compared the performance of these models at different spatial scales and demonstrated how these models can support management decisions like e-flow assessment. Species distribution models can become a powerful tool when they are combined with high-resolution (either spatial or temporal or both) data. Pauwels et al. (2017) for instance analysed the habitat use and preference of northern pike by combining radio telemetry data and species distribution models. They demonstrated the value of good quality habitats in anthropogenic impacted river systems and observed substantial behavioural differences in habitat use between individuals. This not only underlines the importance of habitat heterogeneity, but also suggests that river management options should focus on different individual preferences within a particular target species, and not only on general knowledge of this species. The results also provide insight into the impact of riparian habitat restoration on adult pike and may be used to more efficiently manage pike rivers, e.g. by enhancing the lateral conhttp://dx.doi.org/10.1016/j.limno.2017.03.001 0075-9511/© 2017 Published by Elsevier GmbH.
nectivity with river side arms or by reconstructing natural riparian habitats. Additionally to ecohydraulics articles focusing on species distribution modelling, physical habitat preferences and fish behaviour, the impact of more integrated variables like erosion and sediment load, often at larger spatial scales, is worth investigating. Valero et al. (2017) provided a contribution that assesses the chronic effect of sediment yield on fish communities at 104 river sites located in two different sub-catchments. Due to the integrative and relatively large-scale character of their study, they combined different models to quantify environmental variables and fish response to these variables. One of the most important results of this study is that intermediate values of sediment yield led to maximum densities of the present fish species, which may suggest the benefits of habitat heterogeneity and intermediate sediment yields for fish species. However, when this heterogeneity may be beneficiary at the community level, they can be limiting at the individual species level. This was illustrated by Asaeda and Rashid (2017), who studied one completely submerged and two floating leaved macrophytes under different turbulence velocities. They found that high turbulence velocity inhibits metabolic activities of all three plants, while this effect is not observed at low to medium turbulence for the floating leaved plants. This article demonstrates the role of inventive coping strategies affecting habitat preferences at the species level. Similar coping strategies play a crucial role in the contribution of Yu et al. (2017), who observed longitudinal variations in phytoplankton composition in a river downstream a eutrophic lake. Different phytoplankton species dominated the sampled communities based on their adaptation to lentic, stratified or epilimnic habitats. In addition, the authors showed that functional group analysis may identify the length of the transition zone between different aquatic habitats. Heterogenity in physical conditions is also important when considering fish migration past barriers that should be effective for several fish species. Muraoka et al. (2017) tested the effect on swimming performance of two fish species with different compositions, shape and spatial distribution of boulders in a rocky ramp fishway. They found that a diverse arrangement of boulders is required to allow movement and migration of multiple species. The articles in this Special Issue demonstrate that multidisciplinarity and the ability to combine both theoretical and practical skills, as well as several hydro-environmental sciences are
Editorial / Limnologica 62 (2017) 140–141
needed in applied research. We hope that these examples of ecohydraulics applications can serve as motivation for investigating more of the unknown relationships in ecohydraulics, applying various and combined techniques and sciences to bridge knowledge gaps and ensure sustainable management of water resources in the increasing water–energy–environment nexus. The Guest Editors would like to thank the authors and coauthors of the articles in this Special Issue for their patience in waiting for reviewers’ and editors’ comments, and for their ability to incorporate changes and improving their manuscripts. We would also like to thank all reviewers for their efforts, and Limnologica for their willingness to collaborate and allowing us to publish some of the most interesting contributions seen at the Ecohydraulics Symposium 2014. References Asaeda, Takashi, Rashid, Harun, 2017. Effects of turbulence motion on the growth and physiology of aquatic plants. Limnologica 62, 181–187. ˜ Munoz-Mas, Rafael, Martínez-Capel, Francisco, Alcaraz-Hernández, Juan, Mouton, Ans, 2017. On species distribution modelling, spatial scales and environmental flow assessment with multi-layer perceptron ensembles: a case study on the redfin barbel. Limnologica 62, 161–172.
141
Muraoka, Keiko, Nakanishi, Satoru, Kayaba, Yuichi, 2017. Boulder arrangement on a rocky ramp fishway based on the swimming behavior of fish. Limnologica 62, 188–193. Pauwels, Ine Sara, Goethals, Peter, Coeck, Johan, Mouton, Ans, 2017. Habitat use and preference of adult pike (Esox lucius L.) in an anthropogenically impacted lowland river. Limnologica 62, 151–160. Valero, Celia, Alonso, Carlos, De Miguel, Ramón J., Fernandez-Delgado, Carlos, de Jalon, Diego Garcia, 2017. Response of fish communities in rivers subjected to a high sediment load. Limnologica 62, 142–150. Yu, Qian, Chen, Yongcan, Liu, Zhaowei, Zhu, Dejun, Wang, Haoran, 2017. Longitudinal variations of phytoplankton compositions in lake-to-river systems. Limnologica 62, 173–180.
Ans Mouton Ghent University, Faculty of Bioscience Engineering, Coupure Links 653, 9000 Ghent, Belgium Alte Harby ∗ SINTEF Energy Research, P.O. Box 4761 Sluppen, 7465 Trondheim, Norway ∗ Corresponding
author. E-mail address: [email protected] (A. Harby)
Contents lists available at ScienceDirect
Limnologica journal homepage: www.elsevier.com/locate/limno
Editorial
Ecohydraulic case studies: Interdisciplinarity and technological evolutions
The articles in this Special Issue were presented at the 10th International Symposium on Ecohydraulics in Trondheim, Norway (2014), where the first symposium on ecohydraulics was organised 20 years before. The 10th issue of the symposium celebrated 20 years of ecohydraulic research and had about 300 delegates, giving 194 talks and presenting 86 posters. Over these 20 years, the field of ecohydraulics evolved from physical habitat simulations, mainly focusing on fish and rivers, to an interdisciplinary field of research linking biology, ecology, fluvial geomorphology, sediment transport, hydrology, fluvial hydraulics, river engineering and water resources. Technological evolutions allowed sophisticated data collection and processing, opening opportunities to address new topics like fish behaviour, species distribution modelling and microscale hydraulics. The articles in this special issue illustrate the diversity of ecohydraulic approaches: simulation models, field studies and laboratory or in situ experiments to investigate and analyse the complex relationships present in ecohydraulic problems, always linking to pragmatic management solutions. Since the last decades, advanced data analysis and modelling played a crucial role in selecting the optimal management options. In particular, the species distribution modelling of ecohydraulics shifted from univariate habitat preference curves to complex, multivariate and non-parametric species distribution modelling. This ˜ was illustrated by Munoz-Mas et al. (2017), who applied ensemble modelling techniques that combined different models to develop more robust and accurate models. The authors also compared the performance of these models at different spatial scales and demonstrated how these models can support management decisions like e-flow assessment. Species distribution models can become a powerful tool when they are combined with high-resolution (either spatial or temporal or both) data. Pauwels et al. (2017) for instance analysed the habitat use and preference of northern pike by combining radio telemetry data and species distribution models. They demonstrated the value of good quality habitats in anthropogenic impacted river systems and observed substantial behavioural differences in habitat use between individuals. This not only underlines the importance of habitat heterogeneity, but also suggests that river management options should focus on different individual preferences within a particular target species, and not only on general knowledge of this species. The results also provide insight into the impact of riparian habitat restoration on adult pike and may be used to more efficiently manage pike rivers, e.g. by enhancing the lateral conhttp://dx.doi.org/10.1016/j.limno.2017.03.001 0075-9511/© 2017 Published by Elsevier GmbH.
nectivity with river side arms or by reconstructing natural riparian habitats. Additionally to ecohydraulics articles focusing on species distribution modelling, physical habitat preferences and fish behaviour, the impact of more integrated variables like erosion and sediment load, often at larger spatial scales, is worth investigating. Valero et al. (2017) provided a contribution that assesses the chronic effect of sediment yield on fish communities at 104 river sites located in two different sub-catchments. Due to the integrative and relatively large-scale character of their study, they combined different models to quantify environmental variables and fish response to these variables. One of the most important results of this study is that intermediate values of sediment yield led to maximum densities of the present fish species, which may suggest the benefits of habitat heterogeneity and intermediate sediment yields for fish species. However, when this heterogeneity may be beneficiary at the community level, they can be limiting at the individual species level. This was illustrated by Asaeda and Rashid (2017), who studied one completely submerged and two floating leaved macrophytes under different turbulence velocities. They found that high turbulence velocity inhibits metabolic activities of all three plants, while this effect is not observed at low to medium turbulence for the floating leaved plants. This article demonstrates the role of inventive coping strategies affecting habitat preferences at the species level. Similar coping strategies play a crucial role in the contribution of Yu et al. (2017), who observed longitudinal variations in phytoplankton composition in a river downstream a eutrophic lake. Different phytoplankton species dominated the sampled communities based on their adaptation to lentic, stratified or epilimnic habitats. In addition, the authors showed that functional group analysis may identify the length of the transition zone between different aquatic habitats. Heterogenity in physical conditions is also important when considering fish migration past barriers that should be effective for several fish species. Muraoka et al. (2017) tested the effect on swimming performance of two fish species with different compositions, shape and spatial distribution of boulders in a rocky ramp fishway. They found that a diverse arrangement of boulders is required to allow movement and migration of multiple species. The articles in this Special Issue demonstrate that multidisciplinarity and the ability to combine both theoretical and practical skills, as well as several hydro-environmental sciences are
Editorial / Limnologica 62 (2017) 140–141
needed in applied research. We hope that these examples of ecohydraulics applications can serve as motivation for investigating more of the unknown relationships in ecohydraulics, applying various and combined techniques and sciences to bridge knowledge gaps and ensure sustainable management of water resources in the increasing water–energy–environment nexus. The Guest Editors would like to thank the authors and coauthors of the articles in this Special Issue for their patience in waiting for reviewers’ and editors’ comments, and for their ability to incorporate changes and improving their manuscripts. We would also like to thank all reviewers for their efforts, and Limnologica for their willingness to collaborate and allowing us to publish some of the most interesting contributions seen at the Ecohydraulics Symposium 2014. References Asaeda, Takashi, Rashid, Harun, 2017. Effects of turbulence motion on the growth and physiology of aquatic plants. Limnologica 62, 181–187. ˜ Munoz-Mas, Rafael, Martínez-Capel, Francisco, Alcaraz-Hernández, Juan, Mouton, Ans, 2017. On species distribution modelling, spatial scales and environmental flow assessment with multi-layer perceptron ensembles: a case study on the redfin barbel. Limnologica 62, 161–172.
141
Muraoka, Keiko, Nakanishi, Satoru, Kayaba, Yuichi, 2017. Boulder arrangement on a rocky ramp fishway based on the swimming behavior of fish. Limnologica 62, 188–193. Pauwels, Ine Sara, Goethals, Peter, Coeck, Johan, Mouton, Ans, 2017. Habitat use and preference of adult pike (Esox lucius L.) in an anthropogenically impacted lowland river. Limnologica 62, 151–160. Valero, Celia, Alonso, Carlos, De Miguel, Ramón J., Fernandez-Delgado, Carlos, de Jalon, Diego Garcia, 2017. Response of fish communities in rivers subjected to a high sediment load. Limnologica 62, 142–150. Yu, Qian, Chen, Yongcan, Liu, Zhaowei, Zhu, Dejun, Wang, Haoran, 2017. Longitudinal variations of phytoplankton compositions in lake-to-river systems. Limnologica 62, 173–180.
Ans Mouton Ghent University, Faculty of Bioscience Engineering, Coupure Links 653, 9000 Ghent, Belgium Alte Harby ∗ SINTEF Energy Research, P.O. Box 4761 Sluppen, 7465 Trondheim, Norway ∗ Corresponding
author. E-mail address: [email protected] (A. Harby)