Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration

S. Yoshikawa, A. Yanagawa, Y. Iwasaki, P. Sui, S. Koirala, K. Hirano, A. Khajuria, R. Mahendran, Yukiko Hirabayashi, C. Yoshimura, S. Kanae

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Changes in river discharge due to human activities and climate change would affect the sustainability of freshwater ecosystems. To globally assess how changes in river discharge will affect the future status of freshwater ecosystems, global-scale hydrological simulations need to be connected with a model to estimate the durability of freshwater ecosystems. However, the development of this specific modelling combination for the global scale is still in its infancy. In this study, two statistical methods are introduced to link flow regimes to fish species richness (FSR): one is based on a linear relationship between FSR and mean river discharge (hereafter, FSR-MAD method), and the other is based on a multi-linear relationship between FSR and ecologically relevant flow indices involving several other flow characteristics and mean river discharge (FSR-FLVAR method). The FSR-MAD method has been used previously in global simulation studies. The FSR-FLVAR method is newly introduced here. These statistical methods for estimating FSR were combined with a set of global river discharge simulations to evaluate the potential impact of climate-change-induced flow alterations on FSR changes. Generally, future reductions in FSR with the FSR-FLVAR method are greater and much more scattered than with the FSR-MAD method. In arid regions, both methods indicate reductions in FSR because mean discharge is projected to decrease from past to future, although the magnitude of reductions in FSR is different between the two methods. In contrast, in heavy-snow regions a large reduction in FSR is shown by the FSR-FLVAR method due to increases in the frequency of low and high flows. Although further research is clearly needed to conclude which method is more appropriate, this study demonstrates that the FSR-FLVAR method could produce considerably different results when assessing the global role of flow alterations in changing freshwater ecosystems.

Original languageEnglish
Pages (from-to)621-630
Number of pages10
JournalHydrology and Earth System Sciences
Volume18
Issue number2
DOIs
Publication statusPublished - 2014 Feb 19
Externally publishedYes

Fingerprint

species richness
fish
river discharge
freshwater ecosystem
method
simulation
climate change
arid region
durability
human activity
snow
sustainability

ASJC Scopus subject areas

  • Water Science and Technology
  • Earth and Planetary Sciences (miscellaneous)

Cite this

Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration. / Yoshikawa, S.; Yanagawa, A.; Iwasaki, Y.; Sui, P.; Koirala, S.; Hirano, K.; Khajuria, A.; Mahendran, R.; Hirabayashi, Yukiko; Yoshimura, C.; Kanae, S.

In: Hydrology and Earth System Sciences, Vol. 18, No. 2, 19.02.2014, p. 621-630.

Research output: Contribution to journalArticle

Yoshikawa, S, Yanagawa, A, Iwasaki, Y, Sui, P, Koirala, S, Hirano, K, Khajuria, A, Mahendran, R, Hirabayashi, Y, Yoshimura, C & Kanae, S 2014, 'Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration', Hydrology and Earth System Sciences, vol. 18, no. 2, pp. 621-630. https://doi.org/10.5194/hess-18-621-2014
Yoshikawa, S. ; Yanagawa, A. ; Iwasaki, Y. ; Sui, P. ; Koirala, S. ; Hirano, K. ; Khajuria, A. ; Mahendran, R. ; Hirabayashi, Yukiko ; Yoshimura, C. ; Kanae, S. / Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration. In: Hydrology and Earth System Sciences. 2014 ; Vol. 18, No. 2. pp. 621-630.
@article{64acc6b67b0b42eeaad9d12d3052073c,
title = "Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration",
abstract = "Changes in river discharge due to human activities and climate change would affect the sustainability of freshwater ecosystems. To globally assess how changes in river discharge will affect the future status of freshwater ecosystems, global-scale hydrological simulations need to be connected with a model to estimate the durability of freshwater ecosystems. However, the development of this specific modelling combination for the global scale is still in its infancy. In this study, two statistical methods are introduced to link flow regimes to fish species richness (FSR): one is based on a linear relationship between FSR and mean river discharge (hereafter, FSR-MAD method), and the other is based on a multi-linear relationship between FSR and ecologically relevant flow indices involving several other flow characteristics and mean river discharge (FSR-FLVAR method). The FSR-MAD method has been used previously in global simulation studies. The FSR-FLVAR method is newly introduced here. These statistical methods for estimating FSR were combined with a set of global river discharge simulations to evaluate the potential impact of climate-change-induced flow alterations on FSR changes. Generally, future reductions in FSR with the FSR-FLVAR method are greater and much more scattered than with the FSR-MAD method. In arid regions, both methods indicate reductions in FSR because mean discharge is projected to decrease from past to future, although the magnitude of reductions in FSR is different between the two methods. In contrast, in heavy-snow regions a large reduction in FSR is shown by the FSR-FLVAR method due to increases in the frequency of low and high flows. Although further research is clearly needed to conclude which method is more appropriate, this study demonstrates that the FSR-FLVAR method could produce considerably different results when assessing the global role of flow alterations in changing freshwater ecosystems.",
author = "S. Yoshikawa and A. Yanagawa and Y. Iwasaki and P. Sui and S. Koirala and K. Hirano and A. Khajuria and R. Mahendran and Yukiko Hirabayashi and C. Yoshimura and S. Kanae",
year = "2014",
month = "2",
day = "19",
doi = "10.5194/hess-18-621-2014",
language = "English",
volume = "18",
pages = "621--630",
journal = "Hydrology and Earth System Sciences",
issn = "1027-5606",
publisher = "European Geosciences Union",
number = "2",

}

TY - JOUR

T1 - Illustrating a new global-scale approach to estimating potential reduction in fish species richness due to flow alteration

AU - Yoshikawa, S.

AU - Yanagawa, A.

AU - Iwasaki, Y.

AU - Sui, P.

AU - Koirala, S.

AU - Hirano, K.

AU - Khajuria, A.

AU - Mahendran, R.

AU - Hirabayashi, Yukiko

AU - Yoshimura, C.

AU - Kanae, S.

PY - 2014/2/19

Y1 - 2014/2/19

N2 - Changes in river discharge due to human activities and climate change would affect the sustainability of freshwater ecosystems. To globally assess how changes in river discharge will affect the future status of freshwater ecosystems, global-scale hydrological simulations need to be connected with a model to estimate the durability of freshwater ecosystems. However, the development of this specific modelling combination for the global scale is still in its infancy. In this study, two statistical methods are introduced to link flow regimes to fish species richness (FSR): one is based on a linear relationship between FSR and mean river discharge (hereafter, FSR-MAD method), and the other is based on a multi-linear relationship between FSR and ecologically relevant flow indices involving several other flow characteristics and mean river discharge (FSR-FLVAR method). The FSR-MAD method has been used previously in global simulation studies. The FSR-FLVAR method is newly introduced here. These statistical methods for estimating FSR were combined with a set of global river discharge simulations to evaluate the potential impact of climate-change-induced flow alterations on FSR changes. Generally, future reductions in FSR with the FSR-FLVAR method are greater and much more scattered than with the FSR-MAD method. In arid regions, both methods indicate reductions in FSR because mean discharge is projected to decrease from past to future, although the magnitude of reductions in FSR is different between the two methods. In contrast, in heavy-snow regions a large reduction in FSR is shown by the FSR-FLVAR method due to increases in the frequency of low and high flows. Although further research is clearly needed to conclude which method is more appropriate, this study demonstrates that the FSR-FLVAR method could produce considerably different results when assessing the global role of flow alterations in changing freshwater ecosystems.

AB - Changes in river discharge due to human activities and climate change would affect the sustainability of freshwater ecosystems. To globally assess how changes in river discharge will affect the future status of freshwater ecosystems, global-scale hydrological simulations need to be connected with a model to estimate the durability of freshwater ecosystems. However, the development of this specific modelling combination for the global scale is still in its infancy. In this study, two statistical methods are introduced to link flow regimes to fish species richness (FSR): one is based on a linear relationship between FSR and mean river discharge (hereafter, FSR-MAD method), and the other is based on a multi-linear relationship between FSR and ecologically relevant flow indices involving several other flow characteristics and mean river discharge (FSR-FLVAR method). The FSR-MAD method has been used previously in global simulation studies. The FSR-FLVAR method is newly introduced here. These statistical methods for estimating FSR were combined with a set of global river discharge simulations to evaluate the potential impact of climate-change-induced flow alterations on FSR changes. Generally, future reductions in FSR with the FSR-FLVAR method are greater and much more scattered than with the FSR-MAD method. In arid regions, both methods indicate reductions in FSR because mean discharge is projected to decrease from past to future, although the magnitude of reductions in FSR is different between the two methods. In contrast, in heavy-snow regions a large reduction in FSR is shown by the FSR-FLVAR method due to increases in the frequency of low and high flows. Although further research is clearly needed to conclude which method is more appropriate, this study demonstrates that the FSR-FLVAR method could produce considerably different results when assessing the global role of flow alterations in changing freshwater ecosystems.

UR - http://www.scopus.com/inward/record.url?scp=84897605744&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84897605744&partnerID=8YFLogxK

U2 - 10.5194/hess-18-621-2014

DO - 10.5194/hess-18-621-2014

M3 - Article

AN - SCOPUS:84897605744

VL - 18

SP - 621

EP - 630

JO - Hydrology and Earth System Sciences

JF - Hydrology and Earth System Sciences

SN - 1027-5606

IS - 2

ER -