Assessing risk of estuarine ecosystem collapse

P. C. Mahoney, M. J. Bishop

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Estuarine ecosystems are increasingly threatened by coastal development and climate change. The large number of estuaries globally necessitates risk assessment to prioritise conservation efforts. Schemes for assessing risk of ecosystem collapse have been designed around terrestrial ecosystems, often defined by a single characteristic vegetation type, with their applicability to estuaries unclear. Here we consider the causes and symptoms of estuarine ecosystem collapse and assess, using a case study of the Chesapeake Bay, the applicability of ecosystem-level risk assessments to estuarine ecosystems, typified by mosaics of habitats. Functional estuaries are characterised by habitat heterogeneity and connectivity, maintenance of constituent habitats through recruitment, and a complex trophic structure including apex predators. Additionally, primary production and biomass are dominated by benthic, as opposed to pelagic, species. Hence, homogenisation of habitat types, decreased connectivity, recruitment failure, loss of apex predators and a decreased ratio of benthic to pelagic biomass may be symptoms of a trajectory towards collapse. In terrestrial ecosystems, criteria used for assessing risk of ecosystem collapse include declining or restricted distribution of ecosystems, degradation of the abiotic environment, changes in species composition and declining ecological function. As the boundaries of estuaries are typically defined by topography, rarely do significant changes in the area of the ecosystem occur. Furthermore, because the extent of estuaries is typically small, assessments based on area of occupancy may over-inflate risk. Instead, criteria based on abiotic and biotic changes, many of which are documented through monitoring programs, may be most useful for risk assessments of estuarine ecosystems.
LanguageEnglish
Pages46-58
Number of pages13
JournalOcean and Coastal Management
Volume140
DOIs
Publication statusPublished - May 2017

Fingerprint

estuarine ecosystem
estuary
ecosystems
risk assessment
ecosystem
estuaries
terrestrial ecosystem
connectivity
habitat
predator
coastal development
trophic structure
habitats
biomass
habitat type
vegetation type
primary production
trajectory
predators
topography

Keywords

  • biodiversity assessment
  • threatening processes
  • risk assessment
  • IUCN red list of ecosystems
  • habitat mosaic

Cite this

@article{2349e8360361448f9a0f398431ff037c,
title = "Assessing risk of estuarine ecosystem collapse",
abstract = "Estuarine ecosystems are increasingly threatened by coastal development and climate change. The large number of estuaries globally necessitates risk assessment to prioritise conservation efforts. Schemes for assessing risk of ecosystem collapse have been designed around terrestrial ecosystems, often defined by a single characteristic vegetation type, with their applicability to estuaries unclear. Here we consider the causes and symptoms of estuarine ecosystem collapse and assess, using a case study of the Chesapeake Bay, the applicability of ecosystem-level risk assessments to estuarine ecosystems, typified by mosaics of habitats. Functional estuaries are characterised by habitat heterogeneity and connectivity, maintenance of constituent habitats through recruitment, and a complex trophic structure including apex predators. Additionally, primary production and biomass are dominated by benthic, as opposed to pelagic, species. Hence, homogenisation of habitat types, decreased connectivity, recruitment failure, loss of apex predators and a decreased ratio of benthic to pelagic biomass may be symptoms of a trajectory towards collapse. In terrestrial ecosystems, criteria used for assessing risk of ecosystem collapse include declining or restricted distribution of ecosystems, degradation of the abiotic environment, changes in species composition and declining ecological function. As the boundaries of estuaries are typically defined by topography, rarely do significant changes in the area of the ecosystem occur. Furthermore, because the extent of estuaries is typically small, assessments based on area of occupancy may over-inflate risk. Instead, criteria based on abiotic and biotic changes, many of which are documented through monitoring programs, may be most useful for risk assessments of estuarine ecosystems.",
keywords = "biodiversity assessment, threatening processes, risk assessment, IUCN red list of ecosystems, habitat mosaic",
author = "Mahoney, {P. C.} and Bishop, {M. J.}",
year = "2017",
month = "5",
doi = "10.1016/j.ocecoaman.2017.02.021",
language = "English",
volume = "140",
pages = "46--58",
journal = "Ocean and Coastal Management",
issn = "0964-5691",
publisher = "Elsevier",

}

Assessing risk of estuarine ecosystem collapse. / Mahoney, P. C.; Bishop, M. J.

In: Ocean and Coastal Management, Vol. 140, 05.2017, p. 46-58.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Assessing risk of estuarine ecosystem collapse

AU - Mahoney,P. C.

AU - Bishop,M. J.

PY - 2017/5

Y1 - 2017/5

N2 - Estuarine ecosystems are increasingly threatened by coastal development and climate change. The large number of estuaries globally necessitates risk assessment to prioritise conservation efforts. Schemes for assessing risk of ecosystem collapse have been designed around terrestrial ecosystems, often defined by a single characteristic vegetation type, with their applicability to estuaries unclear. Here we consider the causes and symptoms of estuarine ecosystem collapse and assess, using a case study of the Chesapeake Bay, the applicability of ecosystem-level risk assessments to estuarine ecosystems, typified by mosaics of habitats. Functional estuaries are characterised by habitat heterogeneity and connectivity, maintenance of constituent habitats through recruitment, and a complex trophic structure including apex predators. Additionally, primary production and biomass are dominated by benthic, as opposed to pelagic, species. Hence, homogenisation of habitat types, decreased connectivity, recruitment failure, loss of apex predators and a decreased ratio of benthic to pelagic biomass may be symptoms of a trajectory towards collapse. In terrestrial ecosystems, criteria used for assessing risk of ecosystem collapse include declining or restricted distribution of ecosystems, degradation of the abiotic environment, changes in species composition and declining ecological function. As the boundaries of estuaries are typically defined by topography, rarely do significant changes in the area of the ecosystem occur. Furthermore, because the extent of estuaries is typically small, assessments based on area of occupancy may over-inflate risk. Instead, criteria based on abiotic and biotic changes, many of which are documented through monitoring programs, may be most useful for risk assessments of estuarine ecosystems.

AB - Estuarine ecosystems are increasingly threatened by coastal development and climate change. The large number of estuaries globally necessitates risk assessment to prioritise conservation efforts. Schemes for assessing risk of ecosystem collapse have been designed around terrestrial ecosystems, often defined by a single characteristic vegetation type, with their applicability to estuaries unclear. Here we consider the causes and symptoms of estuarine ecosystem collapse and assess, using a case study of the Chesapeake Bay, the applicability of ecosystem-level risk assessments to estuarine ecosystems, typified by mosaics of habitats. Functional estuaries are characterised by habitat heterogeneity and connectivity, maintenance of constituent habitats through recruitment, and a complex trophic structure including apex predators. Additionally, primary production and biomass are dominated by benthic, as opposed to pelagic, species. Hence, homogenisation of habitat types, decreased connectivity, recruitment failure, loss of apex predators and a decreased ratio of benthic to pelagic biomass may be symptoms of a trajectory towards collapse. In terrestrial ecosystems, criteria used for assessing risk of ecosystem collapse include declining or restricted distribution of ecosystems, degradation of the abiotic environment, changes in species composition and declining ecological function. As the boundaries of estuaries are typically defined by topography, rarely do significant changes in the area of the ecosystem occur. Furthermore, because the extent of estuaries is typically small, assessments based on area of occupancy may over-inflate risk. Instead, criteria based on abiotic and biotic changes, many of which are documented through monitoring programs, may be most useful for risk assessments of estuarine ecosystems.

KW - biodiversity assessment

KW - threatening processes

KW - risk assessment

KW - IUCN red list of ecosystems

KW - habitat mosaic

UR - http://www.scopus.com/inward/record.url?scp=85014480419&partnerID=8YFLogxK

U2 - 10.1016/j.ocecoaman.2017.02.021

DO - 10.1016/j.ocecoaman.2017.02.021

M3 - Article

VL - 140

SP - 46

EP - 58

JO - Ocean and Coastal Management

T2 - Ocean and Coastal Management

JF - Ocean and Coastal Management

SN - 0964-5691

ER -