Abstract
Small hydropower plants (SHPs) are proliferating globally, but their cumulative threat to blocking migratory fish and the fisheries that these fish sustain has been underappreciated when compared with large hydropower plants (LHPs). Here, we quantified the trade-offs between hydroelectric generation capacity and the impacts on river connectivity for thousands of current and projected future dams across Brazil. SHPs are the main source of river fragmentation, resulting in average connectivity losses of fourfold greater than LHPs. Fragmentation by SHPs is projected to increase by 21% in the future, and two-thirds of the 191 migratory species assessed occupy basins that will experience greater connectivity losses due to SHPs than LHPs. A Pareto frontier analysis identified future dam portfolios that could halve the number of hydropower plants that are required to deliver the same energy-generation capacity compared with the least-favourable solutions, while simultaneously resulting in lower river fragmentation and protecting numerous undammed basins. Our results highlight the need for strategic planning that considers the unprecedented growth and cumulative effects of SHPs.
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Data availability
All of the analyses were based on governmental (ANEEL, IBGE, ICMBio) or open source datasets, such as HydroSHEDS and HydroBASINS. All references are included in the text. A repository with a research compendium including non-reproduceable data sources, intermediate products, scripts and guidance to reproduce the results is available at Figshare (https://figshare.com/s/5ba67b7f58ccc812ae70). The output data generated by our analysis are provided in Supplementary Tables 1–6.
Code availability
The code used to analyse the data and generate figures are available at GitHub (https://github.com/messamat/BrazilDCI_Python and https://github.com/messamat/BrazilDCI_R).
References
Grill, G. et al. Mapping the world’s free-flowing rivers. Nature 569, 215–221 (2019).
Zarfl, C., Lumsdon, A. E., Berlekamp, J., Tydecks, L. & Tockner, K. A global boom in hydropower dam construction. Aquat. Sci. 77, 161–170 (2014).
Winemiller, K. O. et al. Balancing hydropower and biodiversity in the Amazon, Congo, and Mekong. Science 351, 128–129 (2016).
Sabo, J. L. et al. Designing river flows to improve food security futures in the Lower Mekong Basin. Science 358, eaao1053 (2017).
Couto, T. B. A. & Olden, J. D. Global proliferation of small hydropower plants—science and policy. Front. Ecol. Environ. 16, 91–100 (2018).
Premalatha, M., Tabassum-Abbasi, Abbasi, T. & Abbasi, S. A. A critical view on the eco-friendliness of small hydroelectric installations. Sci. Total Environ. 481, 638–643 (2014).
Kelly-Richards, S., Silber-Coats, N., Crootof, A., Tecklin, D. & Bauer, C. Governing the transition to renewable energy: a review of impacts and policy issues in the small hydropower boom. Energy Policy 101, 251–264 (2017).
Lange, K. et al. Basin-scale effects of small hydropower on biodiversity dynamics. Front. Ecol. Environ. 16, 397–404 (2018).
Kibler, K. M. & Tullos, D. D. Cumulative biophysical impact of small and large hydropower development in Nu River, China. Water Resour. Res. 49, 3104–3118 (2013).
Timpe, K. & Kaplan, D. The changing hydrology of a dammed Amazon. Sci. Adv. 3, e1700611 (2017).
ANEEL Sistema de Informações de Geração da ANEEL - SIGA (Agência Nacional de Energia Elétrica, accessed 8 December 2020); http://aneel.gov.br/siga
Athayde, S. et al. Improving policies and instruments to address cumulative impacts of small hydropower in the Amazon. Energy Policy 132, 265–271 (2019).
Anderson, E. P. et al. Fragmentation of Andes-to-Amazon connectivity by hydropower dams. Sci. Adv. 4, eaao1642 (2018).
McIntyre, P. B. et al. in Conservation of Freshwater Fishes (eds Closs, G. P. et al.) 324–360 (Cambridge Univ. Press, 2015); https://doi.org/10.1017/cbo9781139627085.012
Hoeinghaus, D. J. et al. Effects of river impoundment on ecosystem services of large tropical rivers: embodied energy and market value of artisanal fisheries. Conserv. Biol. 23, 1222–1231 (2009).
Leite Lima, M. A., Rosa Carvalho, A., Alexandre Nunes, M., Angelini, R. & Rodrigues da Costa Doria, C. Declining fisheries and increasing prices: the economic cost of tropical rivers impoundment. Fish. Res. 221, 105399 (2020).
Arantes, C. C., Fitzgerald, D. B., Hoeinghaus, D. J. & Winemiller, K. O. Impacts of hydroelectric dams on fishes and fisheries in tropical rivers through the lens of functional traits. Curr. Opin. Environ. Sustain. 37, 28–40 (2019).
Costa-Pereira, R., Correa, S. B. & Galetti, M. Fishing-down within populations harms seed dispersal mutualism. Biotropica 50, 319–325 (2018).
Flecker, A. S. et al. Migratory fishes as material and process subsidies in riverine ecosystems. Am. Fish. Soc. Symp. 73, 559–592 (2010).
Goulding, M. et al. Ecosystem-based management of Amazon fisheries and wetlands. Fish Fish. 20, 138–158 (2019).
Tonkin, J. D. et al. The role of dispersal in river network metacommunities: patterns, processes, and pathways. Freshw. Biol. 63, 141–163 (2018).
Cote, D., Kehler, D. G., Bourne, C. & Wiersma, Y. F. A new measure of longitudinal connectivity for stream networks. Landsc. Ecol. 24, 101–113 (2009).
Brennan, A. S. R. et al. Shifting habitat mosaics and fish production across river basins. Science 364, 783–786 (2019).
Tickner, D. et al. Managing rivers for multiple benefits—a coherent approach to research, policy and planning. Front. Environ. Sci. 5, 4 (2017).
Jager, H. I., Efroymson, R. A., Opperman, J. J. & Kelly, M. R. Spatial design principles for sustainable hydropower development in river basins. Renew. Sustain. Energy Rev. 45, 808–816 (2015).
Chen, W. & Olden, J. D. Designing flows to resolve human and environmental water needs in a dam-regulated river. Nat. Commun. 8, 2158 (2017).
Schmitt, R. J. P., Bizzi, S., Castelletti, A. & Kondolf, G. M. Improved trade-offs of hydropower and sand connectivity by strategic dam planning in the mekong. Nat. Sustain. 1, 96–104 (2018).
Almeida, R. M. et al. Reducing greenhouse gas emissions of Amazon hydropower with strategic dam planning. Nat. Commun. 10, 4281 (2019).
Ziv, G., Baran, E., Nam, S., Rodriguez-Iturbe, I. & Levin, S. A. Trading-off fish biodiversity, food security, and hydropower in the Mekong River basin. Proc. Natl Acad. Sci. USA 109, 5609–5614 (2012).
Perkin, J. S. & Gido, K. B. Fragmentation alters stream fish community structure in dendritic ecological networks. Ecol. Appl. 22, 2176–2187 (2012).
Jaeger, K. L., Olden, J. D. & Pelland, N. A. Climate change poised to threaten hydrologic connectivity and endemic fishes in dryland streams. Proc. Natl Acad. Sci. USA 111, 13894–13899 (2014).
Grill, G., Ouellet Dallaire, C., Fluet Chouinard, E., Sindorf, N. & Lehner, B. Development of new indicators to evaluate river fragmentation and flow regulation at large scales: a case study for the Mekong River basin. Ecol. Indic. 45, 148–159 (2014).
Barbarossa, V. et al. Impacts of current and future large dams on the geographic range connectivity of freshwater fish worldwide. Proc. Natl Acad. Sci. USA 117, 3648–3655 (2020).
Instituto Chico Mendes de Conservação da Biodiversidade Livro Vermelho da Fauna Brasileira Ameaçada de Extinção Vol. VI, Peixes (ICMBio/MMA, 2018).
Carolsfield, J., Harvey, B., Ross, C. & Baer, A. Migratory Fishes of South America: Biology, Fisheries and Conservation Status (World Fisheries Trust, World Bank, IDRC, 2003); https://doi.org/10.1596/1-5525-0114-0
Ferreira, J. H. I., Camacho, J. R., Malagoli, J. A. & Guimarães, S. C. J. Assessment of the potential of small hydropower development in Brazil. Renew. Sustain. Energy Rev. 56, 380–387 (2016).
Programas de Governo: Proinfa (Eletrobras, 2019); https://eletrobras.com/en/Paginas/Proinfa.aspx
Latrubesse, E. M. et al. Damming the rivers of the Amazon Basin. Nature 546, 363–369 (2017).
Fearnside, P. M. Amazon dams and waterways: Brazil’s Tapajós Basin plans. Ambio 44, 426–439 (2015).
Farinosi, F. et al. Future climate and land use change impacts on river flows in the Tapajós Basin in the Brazilian Amazon. Earth’s Future 7, 993–1017 (2019).
Almeida, J. D. E. Between distinct voracities: the hydro-energetic machine and the Iyakaliti’s response. Tapiti 12, 93–98 (2014).
Baigún, C., Minotti, P. & Oldani, N. Assessment of sábalo (Prochilodus lineatus) fisheries in the lower Paraná river basin (Argentina) based on hydrological, biological, and fishery indicators. Neotrop. Ichthyol. 11, 199–210 (2013).
Brown, P. H., Tullos, D., Tilt, B., Magee, D. & Wolf, A. T. Modeling the costs and benefits of dam construction from a multidisciplinary perspective. J. Environ. Manage. 90, S303–S311 (2009).
Petheram, C. & McMahon, T. A. Dams, dam costs and damnable cost overruns. J. Hydrol. X 3, 100026 (2019).
Poff, N. L. et al. Sustainable water management under future uncertainty with eco-engineering decision scaling. Nat. Clim. Change 6, 25–34 (2016).
CEPEL Manual for Hydropower Inventory Studies of River Basins English version (Ministry of Mines and Energy, 2007).
Duarte, C. G., Dibo, A. P. A., Siqueira-Gay, J. & Sánchez, L. E. Practitioners’ perceptions of the Brazilian environmental impact assessment system: results from a survey. Impact Assess. Proj. A. 35, 293–309 (2017).
Da Serra Costa, F. et al. Hydropower inventory studies of river basins in Brazil. Int. J. Hydropower Dams 18, 31–36 (2011).
Opperman, J. et al. Connected and Flowing: A Renewable Future for Rivers, Climate and People (WWF and The Nature Conservancy, 2019).
Lehner, B., Verdin, K. & Jarvis, A. New global hydrography derived from spaceborne elevation data. EOS Trans. 89, 93–94 (2008).
Lehner, B. & Grill, G. Global river hydrography and network routing: baseline data and new approaches to study the world’s large river systems. Hydrol. Process. 27, 2171–2186 (2013).
Sistema de Informações Geográficas do Setor Elétrico—SIGEL (ANEEL, 2018).
Potencial dos Recursos Energéticos no Horizonte 2050 (Empresa de Pesquisa Energética, 2018).
Base Cartográfica Contínua 1:250,000 (IBGE, 2019); https://www.ibge.gov.br/geociencias/cartas-e-mapas/
Vera-Escalona, I., Senthivasan, S., Habit, E. & Ruzzante, D. E. Past, present, and future of a freshwater fish metapopulation in a threatened landscape. Conserv. Biol. 32, 849–859 (2018).
Reis, R. E. et al. Fish biodiversity and conservation in South America. J. Fish. Biol. 89, 12–47 (2016).
Comte, L. & Olden, J. D. Evidence for dispersal syndromes in freshwater fishes. Proc. R. Soc. B 285, 20172214 (2018).
Comte, L. & Olden, J. D. Fish dispersal in flowing waters: a synthesis of movement- and genetic-based studies. Fish Fish. 19, 1063–1077 (2018).
Boletim Estatístico da Pesca e Aquicultura (Ministério da Pesca e Aquicultura, 2011).
Freire, K. M. F., Machado, M. L. & Crepaldi, D. Overview of inland recreational fisheries in Brazil. Fisheries 37, 484–494 (2012).
Brönmark, C. et al. There and back again: migration in freshwater fishes. Can. J. Zool. 92, 467–479 (2013).
Noonan, M. J., Grant, J. W. A. & Jackson, C. D. A quantitative assessment of fish passage efficiency. Fish Fish. 13, 450–464 (2012).
Pompeu, P. S., Agostinho, A. & Pelicice, F. M. Existing and future challenges: the concept of successful fish passage in South America. River Res. Appl. 28, 504–512 (2012).
Santos, J. M. et al. Ecohydraulics of pool-type fishways: getting past the barriers. Ecol. Eng. 48, 38–50 (2012).
Januchowski-Hartley, S. R., Jézéquel, C. & Tedesco, P. A. Modelling built infrastructure heights to evaluate common assumptions in aquatic conservation. J. Environ. Manage. 232, 131–137 (2019).
Agostinho, A. A. et al. Fish ladder of Lajeado Dam: migrations on one-way routes? Neotrop. Ichthyol. 5, 121–130 (2007).
Farah-Pérez, A., Umaña-Villalobos, G., Picado-Barboza, J. & Anderson, E. P. An analysis of river fragmentation by dams and river dewatering in Costa Rica. River Res. Appl. 1442–1448 https://doi.org/10.1002/rra.3678 (2020).
Torrente-Vilara, G., Zuanon, J., Leprieur, F., Oberdorff, T. & Tedesco, P. A. Effects of natural rapids and waterfalls on fish assemblage structure in the Madeira River (Amazon Basin). Ecol. Freshw. Fish 20, 588–597 (2011).
Roocks, P. Computing Pareto frontiers and database preferences with the rPref package. R J. 8, 393–404 (2016).
World Energy Outlook (International Energy Agency, 2018).
Acknowledgements
We thank J. Zuanon and R. Reis for validating our migratory species list and ICMBio for sharing their dataset on fish species occurrence; D. Li, D. Martins and J. Rocha for the assistance with the analysis. J.D.O. was supported by a H. Mason Keeler Endowed Professorship from the School of Aquatic and Fishery Sciences, University of Washington, who also supported T.B.A.C.; T.B.A.C. received the CNPq/Science Without Borders Fellowship (203991/2014-1), and research grants from Rufford Foundation and National Geographic Society.
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T.B.A.C. and J.D.O. designed the study, and all of the authors led the writing. T.B.A.C. and M.L.M. worked on the data acquisition, processing and analysis in R, and M.L.M. coded the spatial analysis in Python.
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Supplementary Information
Supplementary Figs. 1–10, Methods and references.
Supplementary Table 1
Estimates of river connectivity loss (DCIp) in the occurrence range of the 365 fish species considered migratory.
Supplementary Table 2
Projected effect of each future hydropower project on river connectivity (DCIp).
Supplementary Table 3
Projected nationwide connectivity loss (DCIp) and generation capacity gains for the favourable future hydropower dam portfolios.
Supplementary Table 4
Estimates of river connectivity loss (DCIi) in the occurrence range of the 365 fish species considered migratory. The DCIi is an estimate of river connectivity loss for migratory fish populations that are predominantly composed of external immigrants from downstream basins (see Supplementary Methods).
Supplementary Table 5
Projected effect of each future hydropower project on river connectivity (DCIi).
Supplementary Table 6
Projected nationwide connectivity loss (DCIi) and generation capacity gains for the favourable future hydropower dam portfolios.
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Couto, T.B.A., Messager, M.L. & Olden, J.D. Safeguarding migratory fish via strategic planning of future small hydropower in Brazil. Nat Sustain 4, 409–416 (2021). https://doi.org/10.1038/s41893-020-00665-4
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DOI: https://doi.org/10.1038/s41893-020-00665-4
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