1
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Larsen S, Joyce F, Vaughan IP, Durance I, Walter JA, Ormerod SJ. Climatic effects on the synchrony and stability of temperate headwater invertebrates over four decades. GLOBAL CHANGE BIOLOGY 2024; 30:e17017. [PMID: 37933478 DOI: 10.1111/gcb.17017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 08/28/2023] [Accepted: 10/20/2023] [Indexed: 11/08/2023]
Abstract
Important clues about the ecological effects of climate change can arise from understanding the influence of other Earth-system processes on ecosystem dynamics but few studies span the inter-decadal timescales required. We, therefore, examined how variation in annual weather patterns associated with the North Atlantic Oscillation (NAO) over four decades was linked to synchrony and stability in a metacommunity of stream invertebrates across multiple, contrasting headwaters in central Wales (UK). Prolonged warmer and wetter conditions during positive NAO winters appeared to synchronize variations in population and community composition among and within streams thereby reducing stability across levels of ecological organization. This climatically mediated synchronization occurred in all streams irrespective of acid-base status and land use, but was weaker where invertebrate communities were more functionally diverse. Wavelet linear models indicated that variation in the NAO explained up to 50% of overall synchrony in species abundances at a timescale of 4-6 years. The NAO appeared to affect ecological dynamics through local variations in temperature, precipitation and discharge, but increasing hydrochemical variability within sites during wetter winters might have contributed. Our findings illustrate how large-scale climatic fluctuations generated over the North Atlantic can affect population persistence and dynamics in inland freshwater ecosystems in ways that transcend local catchment character. Protecting and restoring functional diversity in stream communities might increase their stability against warmer, wetter conditions that are analogues of ongoing climate change. Catchment management could also dampen impacts and provide options for climate change adaptation.
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Affiliation(s)
- Stefano Larsen
- Research and Innovation Centre, Fondazione Edmund Mach, San Michele all' Adige, Italy
| | - Fiona Joyce
- Water Research Institute, Cardiff School of Biosciences, Cardiff University, Cardiff, UK
| | - Ian P Vaughan
- Water Research Institute, Cardiff School of Biosciences, Cardiff University, Cardiff, UK
| | - Isabelle Durance
- Water Research Institute, Cardiff School of Biosciences, Cardiff University, Cardiff, UK
| | - Jonathan A Walter
- Center for Watershed Sciences, University of California, Davis, California, USA
- Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia, USA
| | - Steve J Ormerod
- Water Research Institute, Cardiff School of Biosciences, Cardiff University, Cardiff, UK
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2
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Li F, Zhang Y, Altermatt F, Yang J, Zhang X. Destabilizing Effects of Environmental Stressors on Aquatic Communities and Interaction Networks across a Major River Basin. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7828-7839. [PMID: 37155929 DOI: 10.1021/acs.est.3c00456] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Human-driven environmental stressors are increasingly threatening species survival and diversity of river systems worldwide. However, it remains unclear how the stressors affect the stability changes across aquatic multiple communities. Here, we used environmental DNA (eDNA) data sets from a human-dominated river in China over 3 years and analyzed the stability changes in multiple communities under persistent anthropogenic stressors, including land use and pollutants. First, we found that persistent stressors significantly reduced multifaceted species diversity (e.g., species richness, Shannon's diversity, and Simpson's diversity) and species stability but increased species synchrony across multiple communities. Second, the structures of interaction networks inferred from an empirical meta-food web were significantly changed under persistent stressors, for example, resulting in decreased network modularity and negative/positive cohesion. Third, piecewise structural equation modeling proved that the persistent stress-induced decline in the stability of multiple communities mainly depended upon diversity-mediated pathways rather than the direct effects of stress per se; specifically, the increase of species synchrony and the decline of interaction network modularity were the main biotic drivers of stability variation. Overall, our study highlights the destabilizing effects of persistent stressors on multiple communities as well as the mechanistic dependencies, mainly through reducing species diversity, increasing species synchrony, and changing interaction networks.
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Affiliation(s)
- Feilong Li
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Yan Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, People's Republic of China
| | - Florian Altermatt
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
- Department of Aquatic Ecology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland
| | - Jianghua Yang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, People's Republic of China
| | - Xiaowei Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, People's Republic of China
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3
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Li F, Wang S, Zhang Y, Zhang N, Cai Y, Yang Z. DNA metabarcoding reveals human impacts on macroinvertebrate communities in polluted headwater streams: Evidence from the Liao River in northeast China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 300:118929. [PMID: 35114307 DOI: 10.1016/j.envpol.2022.118929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/25/2022] [Accepted: 01/29/2022] [Indexed: 06/14/2023]
Abstract
Headwater streams are a hotspot of freshwater biodiversity, carrying indispensable resource pools of aquatic species. However, up to now, there remain many challenges to accurately and efficiently characterize the responses of this vulnerable ecosystem to human-induced changes. Here, we collected macroinvertebrate data from 12 different headwater streams in the Liao River of northeast China by DNA metabarcoding approach, to reveal biodiversity changes and ecological thresholds affected by human beings. Our data showed that the community composition and structure of headwater streams had unique and significant differences under human impacts, and 5-day biological oxygen demand (BOD5) and ammonia nitrogen (NH3-N) were the key variables explaining the variation in community structure. Although α diversity had a unimodal relationship with nutrients and organic loads, β diversity and its turnover component (species replacement) increased significantly. In addition, 22 and 33 indicative taxa were identified to have significant negative responses to BOD5 and NH3-N, respectively, and the change points derived from Threshold Indicator Taxa Analysis (TITAN) for the negative response of their frequency and abundance were BOD5 >3.42 mg/L and NH3-N >0.14 mg/L. Overall, this study reveals the biodiversity changes in headwater streams from the aspects of α and β diversity, and also determines the thresholds of BOD5 and NH3-N pollutants for one reach at one date from 12 headwater streams, suggesting the potential of DNA metabarcoding approach for threshold analyses in headwater streams.
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Affiliation(s)
- Feilong Li
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China
| | - Shuping Wang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yuan Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Nan Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yanpeng Cai
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China
| | - Zhifeng Yang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China
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4
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Lee F, Simon KS, Perry GLW. River networks: an analysis of simulating algorithms and graph metrics used to quantify topology. Methods Ecol Evol 2022. [DOI: 10.1111/2041-210x.13854] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Finnbar Lee
- School of Environment The University of Auckland, Private Bag 92019 Auckland New Zealand
| | - Kevin S. Simon
- School of Environment The University of Auckland, Private Bag 92019 Auckland New Zealand
| | - George L. W. Perry
- School of Environment The University of Auckland, Private Bag 92019 Auckland New Zealand
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5
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Terui A, Kim S, Dolph CL, Kadoya T, Miyazaki Y. Emergent dual scaling of riverine biodiversity. Proc Natl Acad Sci U S A 2021; 118:e2105574118. [PMID: 34795054 PMCID: PMC8617499 DOI: 10.1073/pnas.2105574118] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2021] [Indexed: 11/18/2022] Open
Abstract
A prevailing paradigm suggests that species richness increases with area in a decelerating way. This ubiquitous power law scaling, the species-area relationship, has formed the foundation of many conservation strategies. In spatially complex ecosystems, however, the area may not be the sole dimension to scale biodiversity patterns because the scale-invariant complexity of fractal ecosystem structure may drive ecological dynamics in space. Here, we use theory and analysis of extensive fish community data from two distinct geographic regions to show that riverine biodiversity follows a robust scaling law along the two orthogonal dimensions of ecosystem size and complexity (i.e., the dual scaling law). In river networks, the recurrent merging of various tributaries forms fractal branching systems, where the prevalence of branching (ecosystem complexity) represents a macroscale control of the ecosystem's habitat heterogeneity. In the meantime, ecosystem size dictates metacommunity size and total habitat diversity, two factors regulating biodiversity in nature. Our theory predicted that, regardless of simulated species' traits, larger and more branched "complex" networks support greater species richness due to increased space and environmental heterogeneity. The relationships were linear on logarithmic axes, indicating power law scaling by ecosystem size and complexity. In support of this theoretical prediction, the power laws have consistently emerged in riverine fish communities across the study regions (Hokkaido Island in Japan and the midwestern United States) despite hosting different fauna with distinct evolutionary histories. The emergence of dual scaling law may be a pervasive property of branching networks with important implications for biodiversity conservation.
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Affiliation(s)
- Akira Terui
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27412;
| | - Seoghyun Kim
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27412
| | - Christine L Dolph
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN 55108
| | - Taku Kadoya
- Biodiversity Division, National Institute for Environmental Studies, Tsukuba 305-8506, Japan
| | - Yusuke Miyazaki
- Department of Child Education and Welfare, Shiraume Gakuen College, Tokyo 187-8570, Japan
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6
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A Classification Framework to Assess Ecological, Biogeochemical, and Hydrologic Synchrony and Asynchrony. Ecosystems 2021; 25:989-1005. [DOI: 10.1007/s10021-021-00700-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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7
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Fortin MJ, Dale MRT, Brimacombe C. Network ecology in dynamic landscapes. Proc Biol Sci 2021; 288:20201889. [PMID: 33906397 PMCID: PMC8080002 DOI: 10.1098/rspb.2020.1889] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 04/01/2021] [Indexed: 12/25/2022] Open
Abstract
Network ecology is an emerging field that allows researchers to conceptualize and analyse ecological networks and their dynamics. Here, we focus on the dynamics of ecological networks in response to environmental changes. Specifically, we formalize how network topologies constrain the dynamics of ecological systems into a unifying framework in network ecology that we refer to as the 'ecological network dynamics framework'. This framework stresses that the interplay between species interaction networks and the spatial layout of habitat patches is key to identifying which network properties (number and weights of nodes and links) and trade-offs among them are needed to maintain species interactions in dynamic landscapes. We conclude that to be functional, ecological networks should be scaled according to species dispersal abilities in response to landscape heterogeneity. Determining how such effective ecological networks change through space and time can help reveal their complex dynamics in a changing world.
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Affiliation(s)
- Marie-Josée Fortin
- Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
| | - Mark R. T. Dale
- Ecosystem Science and Management, University of Northern British Columbia, Prince George, British Columbia, Canada
| | - Chris Brimacombe
- Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada
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8
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Larsen S, Comte L, Filipa Filipe A, Fortin MJ, Jacquet C, Ryser R, Tedesco PA, Brose U, Erős T, Giam X, Irving K, Ruhi A, Sharma S, Olden JD. The geography of metapopulation synchrony in dendritic river networks. Ecol Lett 2021; 24:791-801. [PMID: 33619868 PMCID: PMC8049041 DOI: 10.1111/ele.13699] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/30/2020] [Accepted: 01/07/2021] [Indexed: 02/07/2023]
Abstract
Dendritic habitats, such as river ecosystems, promote the persistence of species by favouring spatial asynchronous dynamics among branches. Yet, our understanding of how network topology influences metapopulation synchrony in these ecosystems remains limited. Here, we introduce the concept of fluvial synchrogram to formulate and test expectations regarding the geography of metapopulation synchrony across watersheds. By combining theoretical simulations and an extensive fish population time‐series dataset across Europe, we provide evidence that fish metapopulations can be buffered against synchronous dynamics as a direct consequence of network connectivity and branching complexity. Synchrony was higher between populations connected by direct water flow and decayed faster with distance over the Euclidean than the watercourse dimension. Likewise, synchrony decayed faster with distance in headwater than mainstem populations of the same basin. As network topology and flow directionality generate fundamental spatial patterns of synchrony in fish metapopulations, empirical synchrograms can aid knowledge advancement and inform conservation strategies in complex habitats.
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Affiliation(s)
- Stefano Larsen
- Unit of Computational Biology, Research and Innovation Centre, Fondazione Edmund Mach, via E. Mach 1, San Michele all'Adige, 38010, Italy.,Department of Civil Environmental and Mechanical Engineering, University of Trento, Trento, Italy
| | - Lise Comte
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, 98105, USA.,School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - Ana Filipa Filipe
- CIBIO/InBio, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal.,Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, Portugal
| | - Marie-Josée Fortin
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, M5S 3B2, Canada
| | - Claire Jacquet
- Department of Aquatic Ecology, Swiss Federal Institute of Aquatic Science and Technology, Eawag, Dübendorf, Switzerland.,Complex Systems Lab, INRAE - Centre Clermont-Auvergne-Rhône-Alpes, 9 avenue Blaise Pascal, Aubière,, 63170, France.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zürich, Switzerland
| | - Remo Ryser
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, 04103, Germany.,Institute of Biodiversity, Friedrich-Schiller-University Jena, Jena, 07743, Germany
| | - Pablo A Tedesco
- UMR EDB, CNRS 5174, UPS, Université Paul Sabatier, IRD 253, Toulouse, France
| | - Ulrich Brose
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, 04103, Germany.,Institute of Biodiversity, Friedrich-Schiller-University Jena, Jena, 07743, Germany
| | - Tibor Erős
- MTA Centre for Ecological Research, Balaton Limnological Institute, Klebelsberg K. u. 3, Tihany, 8237, Hungary
| | - Xingli Giam
- School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - Katie Irving
- Biology Department, Southern California Coastal Water Research Project, Costa Mesa, CA, 92626, USA.,Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Albert Ruhi
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Sapna Sharma
- Department of Biology, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada
| | - Julian D Olden
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, 98105, USA
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9
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Gross T, Allhoff KT, Blasius B, Brose U, Drossel B, Fahimipour AK, Guill C, Yeakel JD, Zeng F. Modern models of trophic meta-communities. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190455. [PMID: 33131442 PMCID: PMC7662193 DOI: 10.1098/rstb.2019.0455] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2020] [Indexed: 02/06/2023] Open
Abstract
Dispersal and foodweb dynamics have long been studied in separate models. However, over the past decades, it has become abundantly clear that there are intricate interactions between local dynamics and spatial patterns. Trophic meta-communities, i.e. meta-foodwebs, are very complex systems that exhibit complex and often counterintuitive dynamics. Over the past decade, a broad range of modelling approaches have been used to study these systems. In this paper, we review these approaches and the insights that they have revealed. We focus particularly on recent papers that study trophic interactions in spatially extensive settings and highlight the common themes that emerged in different models. There is overwhelming evidence that dispersal (and particularly intermediate levels of dispersal) benefits the maintenance of biodiversity in several different ways. Moreover, some insights have been gained into the effect of different habitat topologies, but these results also show that the exact relationships are much more complex than previously thought, highlighting the need for further research in this area. This article is part of the theme issue 'Integrative research perspectives on marine conservation'.
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Affiliation(s)
- Thilo Gross
- University of California Davis, Department of Computer Science, 1 Shields Avenue, Davis, CA 95616, USA
- Alfred Wegener Institut. Helmholtz Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
- Univeristät Oldenburg, Institut für Chemie und Biologie des Meeres, Carl-von-Ossietzky-Strasse 9-11, 26111 Oldenburg, Germany
- Helmholtz Institute for Functional Marine Bidiversity, Ammerländer Heerstrasse 231, Oldenburg, Germany
| | - Korinna T. Allhoff
- Universität Tübingen, Department of Biology, Auf der Morgenstelle 5, 72076 Tübingen, Germany
| | - Bernd Blasius
- Alfred Wegener Institut. Helmholtz Zentrum für Polar und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
- Univeristät Oldenburg, Institut für Chemie und Biologie des Meeres, Carl-von-Ossietzky-Strasse 9-11, 26111 Oldenburg, Germany
| | - Ulrich Brose
- German Centre for Integrative Biodiversity Research, Deutscher Platz 5e, 04103 Leipzig, Germany
- Institute for Biodiversity, Friedrich Schiller University Jena, Dornburger-Strasse 159, 07743 Jena, Germany
| | - Barbara Drossel
- TU Darmstadt, Institut für Festkörperphysik, Hochschulstrasse 6, 64289 Darmstadt, Germany
| | - Ashkaan K. Fahimipour
- National Oceanic and Atmospheric Administration, Southwest Fisheries Science Center, 110 McAllister Way, Santa Cruz, CA 95060, USA
| | - Christian Guill
- Universität Potsdam, Institut für Biochemie und Biologie, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam, Germany
| | - Justin D. Yeakel
- University of California, Merced, School of Natural Sciences, 5200 North Lake Road, Merced, CA 95343, USA
| | - Fanqi Zeng
- University of Bristol, Department of Engineering Mathematics, Merchant Venturers Building, Bristol BS8 1UB, UK
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10
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Chiu M, Li B, Nukazawa K, Resh VH, Carvajal T, Watanabe K. Branching networks can have opposing influences on genetic variation in riverine metapopulations. DIVERS DISTRIB 2020. [DOI: 10.1111/ddi.13160] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Affiliation(s)
- Ming‐Chih Chiu
- Center for Marine Environmental Studies (CMES) Ehime University Matsuyama Ehime Japan
- Institute of Hydrobiology Chinese Academy of Sciences Wuhan China
| | - Bin Li
- Center for Marine Environmental Studies (CMES) Ehime University Matsuyama Ehime Japan
- Institute of Environment and Ecology Shandong Normal University Jinan China
| | - Kei Nukazawa
- Department of Civil and Environmental Engineering University of Miyazaki Miyazaki Japan
| | - Vincent H. Resh
- Department of Environmental Science, Policy & Management University of California Berkeley CA USA
| | - Thaddeus Carvajal
- Center for Marine Environmental Studies (CMES) Ehime University Matsuyama Ehime Japan
| | - Kozo Watanabe
- Center for Marine Environmental Studies (CMES) Ehime University Matsuyama Ehime Japan
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11
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Carraro L, Bertuzzo E, Fronhofer EA, Furrer R, Gounand I, Rinaldo A, Altermatt F. Generation and application of river network analogues for use in ecology and evolution. Ecol Evol 2020; 10:7537-7550. [PMID: 32760547 PMCID: PMC7391543 DOI: 10.1002/ece3.6479] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/21/2020] [Accepted: 05/26/2020] [Indexed: 01/19/2023] Open
Abstract
Several key processes in freshwater ecology are governed by the connectivity inherent to dendritic river networks. These have extensively been analyzed from a geomorphological and hydrological viewpoint, yet structures classically used in ecological modeling have been poorly representative of the structure of real river basins, often failing to capture well-known scaling features of natural rivers. Pioneering work identified optimal channel networks (OCNs) as spanning trees reproducing all scaling features characteristic of natural stream networks worldwide. While OCNs have been used to create landscapes for studies on metapopulations, biodiversity, and epidemiology, their generation has not been generally accessible.Given the increasing interest in dendritic riverine networks by ecologists and evolutionary biologists, we here present a method to generate OCNs and, to facilitate its application, we provide the R-package OCNet. Owing to the stochastic process generating OCNs, multiple network replicas spanning the same surface can be built; this allows performing computational experiments whose results are irrespective of the particular shape of a single river network. The OCN construct also enables the generation of elevational gradients derived from the optimal network configuration, which can constitute three-dimensional landscapes for spatial studies in both terrestrial and freshwater realms. Moreover, the package provides functions that aggregate OCNs into an arbitrary number of nodes, calculate several descriptors of river networks, and draw relevant network features.We describe the main functionalities of the package and its integration with other R-packages commonly used in spatial ecology. Moreover, we exemplify the generation of OCNs and discuss an application to a metapopulation model for an invasive riverine species.In conclusion, OCNet provides a powerful tool to generate realistic river network analogues for various applications. It thereby allows the design of spatially realistic studies in increasingly impacted ecosystems and enhances our knowledge on spatial processes in freshwater ecology in general.
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Affiliation(s)
- Luca Carraro
- Department of Aquatic EcologySwiss Federal Institute of Aquatic Science and Technology (Eawag)DübendorfSwitzerland
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZürichSwitzerland
| | - Enrico Bertuzzo
- Department of Environmental Sciences, Informatics and StatisticsUniversity of Venice Ca' FoscariVeniceItaly
| | | | - Reinhard Furrer
- Department of Mathematics and Department of Computational ScienceUniversity of ZurichZürichSwitzerland
| | - Isabelle Gounand
- Department of Aquatic EcologySwiss Federal Institute of Aquatic Science and Technology (Eawag)DübendorfSwitzerland
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZürichSwitzerland
- CNRSUPECCNRSIRDINRA, Institut d’écologie et des sciences de l'environnement, IEESSorbonne UniversitéParisFrance
| | - Andrea Rinaldo
- Laboratory of EcohydrologySwiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
- Department of Civil, Environmental and Architectural EngineeringUniversity of PaduaPadovaItaly
| | - Florian Altermatt
- Department of Aquatic EcologySwiss Federal Institute of Aquatic Science and Technology (Eawag)DübendorfSwitzerland
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZürichSwitzerland
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12
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Tsuboi J, Morita K, Koseki Y, Endo S, Sahashi G, Kishi D, Kikko T, Ishizaki D, Nunokawa M, Kanno Y. Spatial covariation of fish population vital rates in a stream network. OIKOS 2020. [DOI: 10.1111/oik.07169] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Jun‐ichi Tsuboi
- Research Center for Freshwater Fisheries, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency JP‐321‐1661 Nikko Japan
| | - Kentaro Morita
- Hokkaido National Fisheries Research Institute, Japan Fisheries Research and Education Agency Sapporo Japan
| | - Yusuke Koseki
- Dept of Life Design, Faculty of Home Economics, Otsuma Women's Univ. Tokyo Japan
| | | | - Genki Sahashi
- Hokkaido National Fisheries Research Institute, Japan Fisheries Research and Education Agency Sapporo Japan
| | - Daisuke Kishi
- Gero Branch, Gifu Prefectural Research Inst. for Fisheries and Aquatic Environments Gero Japan
| | - Takeshi Kikko
- Shiga Prefectural Fisheries Experiment Station Hassaka, Hikone Shiga Japan
| | - Daisuke Ishizaki
- Shiga Prefectural Fisheries Experiment Station Hassaka, Hikone Shiga Japan
| | | | - Yoichiro Kanno
- Dept of Fish, Wildlife, and Conservation Biology, and Graduate Degree Program in Ecology, Colorado State Univ. Fort Collins CO USA
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13
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Kopp DA, Allen DC. Stream network geometry and the spatial influence of aquatic insect subsidies across the contiguous United States. Ecosphere 2019. [DOI: 10.1002/ecs2.2926] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Darin A. Kopp
- Ecology and Evolutionary Biology Program Department of Biology University of Oklahoma Norman Oklahoma 73071 USA
| | - Daniel C. Allen
- Ecology and Evolutionary Biology Program Department of Biology University of Oklahoma Norman Oklahoma 73071 USA
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14
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Zhang Z, Gao J, Cai Y. The effects of environmental factors and geographic distance on species turnover in an agriculturally dominated river network. ENVIRONMENTAL MONITORING AND ASSESSMENT 2019; 191:201. [PMID: 30826892 DOI: 10.1007/s10661-019-7309-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 02/11/2019] [Indexed: 06/09/2023]
Abstract
Both environmental and geographic factors interact to structure the metacommunities in river networks, but the importance of these factors is difficult to distinguish. We used six aquatic taxonomic groups to test the relationship between environmental and geographic factors and their effect on species turnover patterns in an agriculturally dominated river (Chaohu Lake Basin, China). The relationships between three dissimilarity indices and geographic distance were assessed using the Mantel test while considering the differences in environmental factors between sites. Then, we employed a variation partitioning method to distinguish the isolated and combined effects of environmental and geographic distance on species turnover. There were significant relationships between environmental distance and species turnover in all groups. All organisms except periphytic diatoms were significantly correlated with two geographic (Euclidean and network) distances when the Chao dissimilarity index was considered. The results suggest that the strength of the correlations changed with environmental and geographic distances and with the aquatic community. The communities displayed more complex relationships with the distance measures when different dissimilarity (Jaccard, Chao, and Bray-Curtis dissimilarity) indices were considered. Nevertheless, aquatic communities are strongly influenced by both environmental and geographic distance, and the former has a stronger effect than the latter.
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Affiliation(s)
- Zhiming Zhang
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
| | - Junfeng Gao
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
| | - Yongjiu Cai
- Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China
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15
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Yeakel JD, Gibert JP, Gross T, Westley PAH, Moore JW. Eco-evolutionary dynamics, density-dependent dispersal and collective behaviour: implications for salmon metapopulation robustness. Philos Trans R Soc Lond B Biol Sci 2019; 373:rstb.2017.0018. [PMID: 29581402 PMCID: PMC5882987 DOI: 10.1098/rstb.2017.0018] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2018] [Indexed: 11/12/2022] Open
Abstract
The spatial dispersal of individuals plays an important role in the dynamics of populations, and is central to metapopulation theory. Dispersal provides connections within metapopulations, promoting demographic and evolutionary rescue, but may also introduce maladapted individuals, potentially lowering the fitness of recipient populations through introgression of heritable traits. To explore this dual nature of dispersal, we modify a well-established eco-evolutionary model of two locally adapted populations and their associated mean trait values, to examine recruiting salmon populations that are connected by density-dependent dispersal, consistent with collective migratory behaviour that promotes navigation. When the strength of collective behaviour is weak such that straying is effectively constant, we show that a low level of straying is associated with the highest gains in metapopulation robustness and that high straying serves to erode robustness. Moreover, we find that as the strength of collective behaviour increases, metapopulation robustness is enhanced, but this relationship depends on the rate at which individuals stray. Specifically, strong collective behaviour increases the presence of hidden low-density basins of attraction, which may serve to trap disturbed populations, and this is exacerbated by increased habitat heterogeneity. Taken as a whole, our findings suggest that density-dependent straying and collective migratory behaviour may help metapopulations, such as in salmon, thrive in dynamic landscapes. Given the pervasive eco-evolutionary impacts of dispersal on metapopulations, these findings have important ramifications for the conservation of salmon metapopulations facing both natural and anthropogenic contemporary disturbances.This article is part of the theme issue 'Collective movement ecology'.
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Affiliation(s)
- Justin D Yeakel
- School of Natural Sciences, University of California, Merced, CA 95340, USA .,The Santa Fe Institute, Santa Fe, NM 87501, USA
| | - Jean P Gibert
- School of Natural Sciences, University of California, Merced, CA 95340, USA
| | - Thilo Gross
- Department of Engineering Mathematics, University of Bristol, Bristol BS8 1TH, UK
| | - Peter A H Westley
- Department of Fisheries, University of Alaska Fairbanks, Fairbanks, AK 99775, USA
| | - Jonathan W Moore
- Earth2Oceans Research Group, Simon Fraser University, Burnaby BC, Canada V5A 1S6
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16
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Laplacian matrices and Turing bifurcations: revisiting Levin 1974 and the consequences of spatial structure and movement for ecological dynamics. THEOR ECOL-NETH 2019. [DOI: 10.1007/s12080-018-0403-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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17
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de Andreazzi CS, Guimarães PR, Melián CJ. Eco-evolutionary feedbacks promote fluctuating selection and long-term stability of antagonistic networks. Proc Biol Sci 2019. [PMID: 29540515 DOI: 10.1098/rspb.2017.2596] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Studies have shown the potential for rapid adaptation in coevolving populations and that the structure of species interaction networks can modulate the vulnerability of ecological systems to perturbations. Although the feedback loop between population dynamics and coevolution of traits is crucial for understanding long-term stability in ecological assemblages, modelling eco-evolutionary dynamics in species-rich assemblages is still a challenge. We explore how eco-evolutionary feedbacks influence trait evolution and species abundances in 23 empirical antagonistic networks. We show that, if selection due to antagonistic interactions is stronger than other selective pressures, eco-evolutionary feedbacks lead to higher mean species abundances and lower temporal variation in abundances. By contrast, strong selection of antagonistic interactions leads to higher temporal variation of traits and on interaction strengths. Our results present a theoretical link between the study of the species persistence and coevolution in networks of interacting species, pointing out the ways by which coevolution may decrease the vulnerability of species within antagonistic networks to demographic fluctuation.
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Affiliation(s)
- Cecilia Siliansky de Andreazzi
- Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, 05508-090 São Paulo, SP, Brazil .,Fiocruz Mata Atlântica, Fundação Oswaldo Cruz, Estrada Rodrigues Caldas 3400, 22713-375 Rio de Janeiro, RJ, Brazil
| | - Paulo R Guimarães
- Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, 05508-090 São Paulo, SP, Brazil
| | - Carlos J Melián
- Department of Fish Ecology and Evolution, Center for Ecology, Evolution and Biogeochemistry, EAWAG, Dübendorf, Switzerland
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18
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Interaction paths promote module integration and network-level robustness of spliceosome to cascading effects. Sci Rep 2018; 8:17441. [PMID: 30487551 PMCID: PMC6261937 DOI: 10.1038/s41598-018-35160-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 10/26/2018] [Indexed: 11/22/2022] Open
Abstract
The functionality of distinct types of protein networks depends on the patterns of protein-protein interactions. A problem to solve is understanding the fragility of protein networks to predict system malfunctioning due to mutations and other errors. Spectral graph theory provides tools to understand the structural and dynamical properties of a system based on the mathematical properties of matrices associated with the networks. We combined two of such tools to explore the fragility to cascading effects of the network describing protein interactions within a key macromolecular complex, the spliceosome. Using S. cerevisiae as a model system we show that the spliceosome network has more indirect paths connecting proteins than random networks. Such multiplicity of paths may promote routes to cascading effects to propagate across the network. However, the modular network structure concentrates paths within modules, thus constraining the propagation of such cascading effects, as indicated by analytical results from the spectral graph theory and by numerical simulations of a minimal mathematical model parameterized with the spliceosome network. We hypothesize that the concentration of paths within modules favors robustness of the spliceosome against failure, but may lead to a higher vulnerability of functional subunits, which may affect the temporal assembly of the spliceosome. Our results illustrate the utility of spectral graph theory for identifying fragile spots in biological systems and predicting their implications.
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19
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Brechtel A, Gramlich P, Ritterskamp D, Drossel B, Gross T. Master stability functions reveal diffusion-driven pattern formation in networks. Phys Rev E 2018; 97:032307. [PMID: 29776185 DOI: 10.1103/physreve.97.032307] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Indexed: 11/07/2022]
Abstract
We study diffusion-driven pattern formation in networks of networks, a class of multilayer systems, where different layers have the same topology, but different internal dynamics. Agents are assumed to disperse within a layer by undergoing random walks, while they can be created or destroyed by reactions between or within a layer. We show that the stability of homogeneous steady states can be analyzed with a master stability function approach that reveals a deep analogy between pattern formation in networks and pattern formation in continuous space. For illustration, we consider a generalized model of ecological meta-food webs. This fairly complex model describes the dispersal of many different species across a region consisting of a network of individual habitats while subject to realistic, nonlinear predator-prey interactions. In this example, the method reveals the intricate dependence of the dynamics on the spatial structure. The ability of the proposed approach to deal with this fairly complex system highlights it as a promising tool for ecology and other applications.
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Affiliation(s)
- Andreas Brechtel
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Philipp Gramlich
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Daniel Ritterskamp
- Department of Engineering Mathematics, Merchant Venturers School of Engineering, University of Bristol, Woodland Road, Bristol BS8 1UB, United Kingdom
| | - Barbara Drossel
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Thilo Gross
- Department of Engineering Mathematics, Merchant Venturers School of Engineering, University of Bristol, Woodland Road, Bristol BS8 1UB, United Kingdom
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20
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Terui A, Ishiyama N, Urabe H, Ono S, Finlay JC, Nakamura F. Metapopulation stability in branching river networks. Proc Natl Acad Sci U S A 2018; 115:E5963-E5969. [PMID: 29895695 PMCID: PMC6042068 DOI: 10.1073/pnas.1800060115] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intraspecific population diversity (specifically, spatial asynchrony of population dynamics) is an essential component of metapopulation stability and persistence in nature. In 2D systems, theory predicts that metapopulation stability should increase with ecosystem size (or habitat network size): Larger ecosystems will harbor more diverse subpopulations with more stable aggregate dynamics. However, current theories developed in simplified landscapes may be inadequate to predict emergent properties of branching ecosystems, an overlooked but widespread habitat geometry. Here, we combine theory and analyses of a unique long-term dataset to show that a scale-invariant characteristic of fractal river networks, branching complexity (measured as branching probability), stabilizes watershed metapopulations. In riverine systems, each branch (i.e., tributary) exhibits distinctive ecological dynamics, and confluences serve as "merging" points of those branches. Hence, increased levels of branching complexity should confer a greater likelihood of integrating asynchronous dynamics over the landscape. We theoretically revealed that the stabilizing effect of branching complexity is a consequence of purely probabilistic processes in natural conditions, where within-branch synchrony exceeds among-branch synchrony. Contrary to current theories developed in 2D systems, metapopulation size (a variable closely related to ecosystem size) had vague effects on metapopulation stability. These theoretical predictions were supported by 18-y observations of fish populations across 31 watersheds: Our cross-watershed comparisons revealed consistent stabilizing effects of branching complexity on metapopulations of very different riverine fishes. A strong association between branching complexity and metapopulation stability is likely to be a pervasive feature of branching networks that strongly affects species persistence during rapid environmental changes.
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Affiliation(s)
- Akira Terui
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN 55108;
- Department of Forest Science, Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan
| | - Nobuo Ishiyama
- Department of Forest Science, Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan
| | - Hirokazu Urabe
- Salmon and Freshwater Fisheries Research Institute, Hokkaido Research Organization, 061-1433 Eniwa, Japan
| | - Satoru Ono
- Institute of Environmental Sciences, Hokkaido Research Organization, 060-0819 Sapporo, Japan
| | - Jacques C Finlay
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, MN 55108
| | - Futoshi Nakamura
- Department of Forest Science, Graduate School of Agriculture, Hokkaido University, 060-8589 Sapporo, Japan
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21
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Fullerton AH, Burke BJ, Lawler JJ, Torgersen CE, Ebersole JL, Leibowitz SG. Simulated juvenile salmon growth and phenology respond to altered thermal regimes and stream network shape. Ecosphere 2017; 8:1-23. [PMID: 29552374 DOI: 10.1002/ecs2.2052] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
It is generally accepted that climate change will stress coldwater species like Pacific salmon. However, it is unclear what aspect of altered thermal regimes (e.g., warmer winters, springs, summers, or increased variability) will have the greatest effect, and what role the spatial properties of river networks play. Thermally diverse habitats may afford protection from climate change by providing opportunities for aquatic organisms to find and use habitats with optimal conditions for growth. We hypothesized that climate-altered thermal regimes will change growth and timing of life history events such as emergence or migration but that changes will be moderated in topologically complex stream networks where opportunities to thermoregulate are more readily available to mobile animals. Because climate change effects on populations are spatially variable and contingent upon physiological optima, assessments of risk must take a spatially explicit approach. We developed a spatially-structured individual based model for Chinook Salmon (Oncorhynchus tshawytscha) in which movement decisions and growth were governed by water temperature and conspecific density. We evaluated growth and phenology (timing of egg emergence and smolting) under a variety of thermal regimes (each having a different minimum, rate of warming, maximum, and variability) and in three network shapes of increasing spatial complexity. Across networks, fish generally grew faster and were capable of smolting earlier in warmer scenarios where water temperatures experienced by fish were closer to optimal; however, growth decreased for some fish. We found that salmon size and smolt date responded more strongly to warmer springs and summers than to warmer winters or increased variability. Fish in the least complex network grew faster and were ready to smolt earlier than fish in the more spatially complex network shapes in the contemporary thermal regime; patterns were similar but less clear in warmer thermal regimes. Our results demonstrate that network topology may influence how fish respond to thermal landscapes, and this information will be useful for incorporating a spatiotemporal context into conservation decisions that promote long-term viability of salmon in a changing climate.
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Affiliation(s)
- Aimee H Fullerton
- Fish Ecology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd E, Seattle WA, 98112, USA
| | - Brian J Burke
- Fish Ecology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd E, Seattle WA, 98112, USA
| | - Joshua J Lawler
- School of Environmental and Forest Sciences, University of Washington, Box 352100, Seattle, WA, 98195-2100, USA
| | - Christian E Torgersen
- U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, Cascadia Field Station, University of Washington, Box 352100, Seattle, WA, 98195-2100, USA
| | - Joseph L Ebersole
- National Health and Environmental Effects Research Laboratory, Western Ecology Division, U.S. Environmental Protection Agency, 200 SW 35 St., Corvallis, OR, 97333, USA
| | - Scott G Leibowitz
- National Health and Environmental Effects Research Laboratory, Western Ecology Division, U.S. Environmental Protection Agency, 200 SW 35 St., Corvallis, OR, 97333, USA
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22
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Swan CM, Brown BL. Metacommunity theory meets restoration: isolation may mediate how ecological communities respond to stream restoration. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2017; 27:2209-2219. [PMID: 28718193 DOI: 10.1002/eap.1602] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 05/13/2017] [Accepted: 05/23/2017] [Indexed: 05/24/2023]
Abstract
An often-cited benefit of river restoration is an increase in biodiversity or shift in composition to more desirable taxa. Yet, hard manipulations of habitat structure often fail to elicit a significant response in terms of biodiversity patterns. In contrast to conventional wisdom, the dispersal of organisms may have as large an influence on biodiversity patterns as environmental conditions. This influence of dispersal may be particularly influential in river networks that are linear branching, or dendritic, and thus constrain most dispersal to the river corridor. As such, some locations in river networks, such as isolated headwaters, are expected to respond less to environmental factors and less by dispersal than more well-connected downstream reaches. We applied this metacommunity framework to study how restoration drives biodiversity patterns in river networks. By comparing assemblage structure in headwater vs. more well-connected mainstem sites, we learned that headwater restoration efforts supported higher biodiversity and exhibited more stable ecological communities compared with adjacent, unrestored reaches. Such differences were not evident in mainstem reaches. Consistent with theory and mounting empirical evidence, we attribute this finding to a relatively higher influence of dispersal-driven factors on assemblage structure in more well-connected, higher order reaches. An implication of this work is that, if biodiversity is to be a goal of restoration activity, such local manipulations of habitat should elicit a more profound response in small, isolated streams than in larger downstream reaches. These results offer another significant finding supporting the notion that restoration activity cannot proceed in isolation of larger-scale, catchment-level degradation.
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Affiliation(s)
- Christopher M Swan
- Department of Geography & Environmental Systems, University of Maryland, Baltimore County, 211 Sondheim Hall, 1000 Hilltop Circle, Baltimore, Maryland, 21250, USA
- Center for Urban Environmental Research & Education, University of Maryland, Baltimore County, 211 Sondheim Hall, 1000 Hilltop Circle, Baltimore, Maryland, 21250, USA
| | - Bryan L Brown
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, 24061, USA
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23
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Fullerton AH, Anzalone S, Moran P, Van Doornik DM, Copeland T, Zabel RW. Setting spatial conservation priorities despite incomplete data for characterizing metapopulations. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2016; 26:2558-2578. [PMID: 27865061 DOI: 10.1002/eap.1411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 06/13/2016] [Accepted: 06/22/2016] [Indexed: 06/06/2023]
Abstract
Management of spatially structured species poses unique challenges. Despite a strong theoretical foundation, practitioners rarely have sufficient empirical data to evaluate how populations interact. Rather, assumptions about connectivity and source-sink dynamics are often based on incomplete, extrapolated, or modeled data, if such interactions are even considered at all. Therefore, it has been difficult to evaluate whether spatially structured species are meeting conservation goals. We evaluated how estimated metapopulation structure responded to estimates of population sizes and dispersal probabilities and to the set of populations included. We then compared outcomes of alternative management strategies that target conservation of metapopulation processes. We illustrated these concepts for Chinook salmon (Oncorhynchus tshawytscha) in the Snake River, USA. Our description of spatial structure for this metapopulation was consistent with previous characterizations. We found substantial differences in estimated metapopulation structure when we had incomplete information about all populations and when we used different sources of data (three empirical, two modeled) to estimate dispersal, whereas responses to population size estimates were more consistent. Together, these findings suggest that monitoring efforts should target all populations occasionally and populations that play key roles frequently and that multiple types of data should be collected when feasible. When empirical data are incomplete or of uneven quality, analyses using estimates produced from an ensemble of available datasets can help conservation planners and managers weigh near-term options. Doing so, we found trade-offs in connectivity and source dominance in metapopulation-level responses to alternative management strategies that suggest which types of approaches may be inherently less risky.
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Affiliation(s)
- A H Fullerton
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
| | - S Anzalone
- University of Western Washington, 516 High Street, Bellingham, Washington, 98225, USA
| | - P Moran
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
| | - D M Van Doornik
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
| | - T Copeland
- Idaho Department of Fish and Game, Southwest Region, 1414 E Locust Lane, Nampa, Idaho, 83686, USA
| | - R W Zabel
- Fish Ecology and Conservation Biology Divisions, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard E, Seattle, Washington, 98125, USA
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24
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Sarhad J, Manifold S, Anderson KE. Geometric indicators of population persistence in branching continuous-space networks. J Math Biol 2016; 74:981-1009. [PMID: 27544197 DOI: 10.1007/s00285-016-1045-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 05/11/2016] [Indexed: 10/21/2022]
Abstract
We study population persistence in branching tree networks emulating systems such as river basins, cave systems, organisms on vegetation surfaces, and vascular networks. Population dynamics are modeled using a reaction-diffusion-advection equation on a metric graph which provides a continuous, spatially explicit model of network habitat. A metric graph, in contrast to a standard graph, allows for population dynamics to occur within edges rather than just at graph vertices, subsequently adding a significant level of realism. Within this framework, we stochastically generate branching tree networks with a variety of geometric features and explore the effects of network geometry on the persistence of a population which advects toward a lethal outflow boundary. We identify a metric (CM), the distance from the lethal outflow point at which half of the habitable volume of the network lies upstream of, as a promising indicator of population persistence. This metric outperforms other metrics such as the maximum and minimum distances from the lethal outflow to an upstream boundary and the total habitable volume of the network. The strength of CM as a predictor of persistence suggests that it is a proper "system length" for the branching networks we examine here that generalizes the concept of habitat length in the classical linear space models.
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Affiliation(s)
- Jonathan Sarhad
- Department of Biology, University of California, Riverside, CA, 92521, USA
| | - Scott Manifold
- Department of Engineering Science and Applied Mathematics, Northwestern University, Evanston, IL, USA
| | - Kurt E Anderson
- Department of Biology, University of California, Riverside, CA, 92521, USA.
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25
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Salisbury SJ, McCracken GR, Keefe D, Perry R, Ruzzante DE. A portrait of a sucker using landscape genetics: how colonization and life history undermine the idealized dendritic metapopulation. Mol Ecol 2016; 25:4126-45. [PMID: 27393723 DOI: 10.1111/mec.13757] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 06/28/2016] [Accepted: 06/28/2016] [Indexed: 01/19/2023]
Abstract
Dendritic metapopulations have been attributed unique properties by in silico studies, including an elevated genetic diversity relative to a panmictic population of equal total size. These predictions have not been rigorously tested in nature, nor has there been full consideration of the interacting effects among contemporary landscape features, colonization history and life history traits of the target species. We tested for the effects of dendritic structure as well as the relative importance of life history, environmental barriers and historical colonization on the neutral genetic structure of a longnose sucker (Catostomus catostomus) metapopulation in the Kogaluk watershed of northern Labrador, Canada. Samples were collected from eight lakes, genotyped with 17 microsatellites, and aged using opercula. Lakes varied in differentiation, historical and contemporary connectivity, and life history traits. Isolation by distance was detected only by removing two highly genetically differentiated lakes, suggesting a lack of migration-drift equilibrium and the lingering influence of historical factors on genetic structure. Bayesian analyses supported colonization via the Kogaluk's headwaters. The historical concentration of genetic diversity in headwaters inferred by this result was supported by high historical and contemporary effective sizes of the headwater lake, T-Bone. Alternatively, reduced allelic richness in headwaters confirmed the dendritic structure's influence on gene flow, but this did not translate to an elevated metapopulation effective size. A lack of equilibrium and upstream migration may have dampened the effects of dendritic structure. We suggest that interacting historical and contemporary factors prevent the achievement of the idealized traits of a dendritic metapopulation in nature.
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Affiliation(s)
- Sarah J Salisbury
- Department of Biology, Dalhousie University, Halifax, NS, B3H4R2, Canada
| | | | - Donald Keefe
- Department of Environment and Conservation, Newfoundland and Labrador, Corner Brook, NL, Canada
| | - Robert Perry
- Department of Environment and Conservation, Newfoundland and Labrador, Corner Brook, NL, Canada
| | - Daniel E Ruzzante
- Department of Biology, Dalhousie University, Halifax, NS, B3H4R2, Canada
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26
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Kuglerová L, Jansson R, Sponseller RA, Laudon H, Malm-Renöfält B. Local and regional processes determine plant species richness in a river-network metacommunity. Ecology 2015; 96:381-91. [PMID: 26240860 DOI: 10.1890/14-0552.1] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
River systems form dendritic ecological networks that influence the spatial structure of riverine communities. Few empirical studies have evaluated how regional, dispersal-related processes and local habitat factors interact to govern network patterns of species composition. We explore such interactions in a boreal watershed and show that riparian plant species richness increases strongly with drainage size, i.e., with downstream position in the network. Assemblage composition was nested, with new species successively added downstream. These spatial patterns in species composition were related to a combination of local and regional processes. Breadth in local habitat conditions increased downstream in the network, resulting in higher habitat heterogeneity and reduced niche overlap among species, which together with similar trends in disturbance, allows more species to coexist. Riparian edaphic conditions were also increasingly favorable to more species within the regional pool along larger streams, with greater nitrogen availability (manifested as lower C:N) and more rapid mineralization of C and N (as indicated by ratios of stable isotopes) observed with downstream position in the network. The number of species with the capacity for water dispersal increased with stream size, providing a mechanistic link between plant traits and the downstream accumulation of species as more propagules arrive from upstream sites. Similarity in species composition between sites was related to both geographical and environmental distance. Our results provide the first empirical evidence that position in the river network drives spatial patterns in riparian plant diversity and composition by the joint influence of local (disturbance, habitat conditions, and habitat breadth) and regional (dispersal) forces.
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27
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Fuller MR, Doyle MW, Strayer DL. Causes and consequences of habitat fragmentation in river networks. Ann N Y Acad Sci 2015; 1355:31-51. [DOI: 10.1111/nyas.12853] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew R. Fuller
- Nicholas School of the Environment; Duke University; Durham North Carolina
| | - Martin W. Doyle
- Nicholas School of the Environment; Duke University; Durham North Carolina
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28
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Seymour M, Fronhofer EA, Altermatt F. Dendritic network structure and dispersal affect temporal dynamics of diversity and species persistence. OIKOS 2015. [DOI: 10.1111/oik.02354] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Mathew Seymour
- Eawag: Swiss Federal Inst. of Aquatic Science and Technology; Dept of Aquatic Ecology; Überlandstrasse 133 CH-8600 Dübendorf Switzerland
- Dept of Environmental Systems Science; ETH Zentrum; CHN H41 CH-8092 Zürich Switzerland
| | - Emanuel A. Fronhofer
- Eawag: Swiss Federal Inst. of Aquatic Science and Technology; Dept of Aquatic Ecology; Überlandstrasse 133 CH-8600 Dübendorf Switzerland
| | - Florian Altermatt
- Eawag: Swiss Federal Inst. of Aquatic Science and Technology; Dept of Aquatic Ecology; Überlandstrasse 133 CH-8600 Dübendorf Switzerland
- Inst. of Evolutionary Biology and Environmental Studies, Univ. of Zurich; Winterthurerstr. 190 CH-8057 Zürich Switzerland
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Anderson SC, Moore JW, McClure MM, Dulvy NK, Cooper AB. Portfolio conservation of metapopulations under climate change. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2015; 25:559-72. [PMID: 26263675 DOI: 10.1890/14-0266.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Climate change is likely to lead to increasing population variability and extinction risk. Theoretically, greater population diversity should buffer against rising climate variability, and this theory is often invoked as a reason for greater conservation. However, this has rarely been quantified. Here we show how a portfolio approach to managing population diversity can inform metapopulation conservation priorities in a changing world. We develop a salmon metapopulation model in which productivity is driven by spatially distributed thermal tolerance and patterns of short- and long-term climate change. We then implement spatial conservation scenarios that control population carrying capacities and evaluate the metapopulation portfolios as a financial manager might: along axes of conservation risk and return. We show that preserving a diversity of thermal tolerances minimizes risk, given environmental stochasticity, and ensures persistence, given long-term environmental change. When the thermal tolerances of populations are unknown, doubling the number of populations conserved may nearly halve expected metapopulation variability. However, this reduction in variability can come at the expense of long-term persistence if climate change increasingly restricts available habitat, forcing ecological managers to balance society's desire for short-term stability and long-term viability. Our findings suggest the importance of conserving the processes that promote thermal-tolerance diversity, such as genetic diversity, habitat heterogeneity, and natural disturbance regimes, and demonstrate that diverse natural portfolios may be critical for metapopulation conservation in the face of increasing climate variability and change.
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Moore JW, Beakes MP, Nesbitt HK, Yeakel JD, Patterson DA, Thompson LA, Phillis CC, Braun DC, Favaro C, Scott D, Carr-Harris C, Atlas WI. Emergent stability in a large, free-flowing watershed. Ecology 2015; 96:340-7. [DOI: 10.1890/14-0326.1] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Bellmore JR, Baxter CV, Connolly PJ. Spatial complexity reduces interaction strengths in the meta‐food web of a river floodplain mosaic. Ecology 2015; 96:274-83. [DOI: 10.1890/14-0733.1] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- J. Ryan Bellmore
- Forest and Rangeland Ecosystem Science Center, U.S. Geological Survey, 777 NW 9th Street, Suite 400, Corvallis, Oregon 97330 USA
- Columbia River Research Laboratory, Western Fisheries Research Center, U.S. Geological Survey, Cook, Washington 98605 USA
- Stream Ecology Center, Department of Biological Sciences, Idaho State University, Pocatello, Idaho 83209-8007 USA
| | - Colden V. Baxter
- Stream Ecology Center, Department of Biological Sciences, Idaho State University, Pocatello, Idaho 83209-8007 USA
| | - Patrick J. Connolly
- Columbia River Research Laboratory, Western Fisheries Research Center, U.S. Geological Survey, Cook, Washington 98605 USA
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Terui A, Miyazaki Y, Yoshioka A, Kaifu K, Matsuzaki SIS, Washitani I. Asymmetric dispersal structures a riverine metapopulation of the freshwater pearl mussel Margaritifera laevis. Ecol Evol 2014; 4:3004-14. [PMID: 25247058 PMCID: PMC4161174 DOI: 10.1002/ece3.1135] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 05/06/2014] [Accepted: 05/13/2014] [Indexed: 12/03/2022] Open
Abstract
Unidirectional water flow results in the downstream-biased, asymmetric dispersal of many riverine organisms. However, little is known of how asymmetric dispersal influences riverine population structure and dynamics, limiting our ability to properly manage riverine organisms. A metapopulation of the freshwater pearl mussel Margaritifera laevis may be sensitive to river currents because mussels are repeatedly exposed to downstream drift during floods-a parasitic life stage is the only, limited period (∼40 days) during which larvae (glochidia) can move upstream with the aid of host fish. We hypothesized that water-mediated dispersal would overwhelm upstream dispersal via host fish, and therefore, that upstream subpopulations play a critical role as immigrant sources. To test this hypothesis, we examined the effects of both up- and downstream immigrant sources on the size of target subpopulations in the Shubuto River system, Hokkaido, Japan. We found that target subpopulation size was dependent on the upstream distribution range of reproductive subpopulations and the number of upstream tributaries, which are proxies for the number of potential immigrants moving downstream. In contrast, little influence was observed of downstream immigrant sources (proximity to downstream reproductive subpopulations). These results were consistent even after accounting for local environments and stream size. Our finding suggests that upstream subpopulations can be disproportionately important as immigrant sources when dispersal is strongly asymmetric.
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Affiliation(s)
- Akira Terui
- Department of Ecosystem Studies, Graduate School of Agricultural and Life Sciences, University of Tokyo1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
- Department of Forest Science, Graduate School of Agriculture, Hokkaido UniversityKita 9, Nishi 9, Kita-ku, Sapporo, 060-8589, Japan
| | - Yusuke Miyazaki
- Kanagawa Prefectural Museum of Natural History499 Iryuda, Odawara, Kanagawa, 250-0031, Japan
| | - Akira Yoshioka
- Department of Ecosystem Studies, Graduate School of Agricultural and Life Sciences, University of Tokyo1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
- National Institute for Environmental StudiesTsukuba-shi, Ibaraki, 305-8506, Japan
| | - Kenzo Kaifu
- Department of Ecosystem Studies, Graduate School of Agricultural and Life Sciences, University of Tokyo1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
- Faculty of Law, Chuo UniversityHachioji-shi, Higashi-nakano 742-1, Tokyo, 192-0393, Japan
| | | | - Izumi Washitani
- Department of Ecosystem Studies, Graduate School of Agricultural and Life Sciences, University of Tokyo1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
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Moore JW, Yeakel JD, Peard D, Lough J, Beere M. Life-history diversity and its importance to population stability and persistence of a migratory fish: steelhead in two large North American watersheds. J Anim Ecol 2014; 83:1035-46. [DOI: 10.1111/1365-2656.12212] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 02/03/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Jonathan W. Moore
- Earth to Ocean Research Group; Simon Fraser University; 8888 University Drive Burnaby BC Canada V5A 1S6
| | - Justin D. Yeakel
- Earth to Ocean Research Group; Simon Fraser University; 8888 University Drive Burnaby BC Canada V5A 1S6
| | - Dean Peard
- Ministry of Environment; 3726 Alfred Avenue Smithers BC Canada V0J 2N0
| | - Jeff Lough
- British Columbia Ministry of Forests, Lands and Natural Resource Operations; 3726 Alfred Avenue Smithers BC Canada V0J 2N0
| | - Mark Beere
- British Columbia Ministry of Forests, Lands and Natural Resource Operations; 3726 Alfred Avenue Smithers BC Canada V0J 2N0
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