Forest structure, flooding and grazing predict understorey composition of floodplain forests in southeastern Australia

Gillis Horner, Shaun Cunningham, Jim THOMSON, Patrick J. Baker, Ralph MAC NALLY

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

Most floodplains have been drastically altered by vegetation clearance and river regulation for human needs. In the mid-latitudes, these degraded ecosystems now face the formidable challenge of rapid warming and drying of climates. If the plant diversity of floodplain forests is to be maintained under future climates, their management must be informed by an understanding of how anthropogenic stressors and environmental gradients shape these ecosystems. We used a field survey to examine the potential drivers (forest structure, flooding and anthropogenic disturbance e.g. grazing and logging) of species richness and composition of Eucalyptus camaldulensis floodplain forests in southeastern Australia. Ninety–three stands were surveyed over 15,500 ha of forest, covering a representative range of forest structures and landscape positions, on a mesic and a semi-arid floodplain. Forest structure was an important predictor of the richness and composition of the understorey of river red gum forests on both floodplains. In particular, richness of native species was associated negatively with increasing canopy cover. On the semi-arid floodplain, where there was recent flooding and grazing, these disturbances were also associated with changes in understorey composition. Recent flooding was associated positively with native species richness, with flooded stands having twice the number of native species found in unflooded stands. Recent grazing was associated with an increase in species richness, which may reflect the concentration of herbivores around flooded areas. Targeted thinning to increase structural diversity among stands may temporarily enhance habitat heterogeneity and plant diversity of floodplain forests. If a diverse, native floodplain forest community is to be sustained in these landscapes, management must include regular flooding that approximates the diversity of historical flooding regimes.
Original languageEnglish
Pages (from-to)148-158
Number of pages11
JournalForest Ecology and Management
Volume286
DOIs
Publication statusPublished - 2012
Externally publishedYes

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floodplain forest
floodplains
understory
flooding
grazing
floodplain
native species
species richness
species diversity
Eucalyptus camaldulensis
indigenous species
disturbance
ecosystem
climate
environmental gradient
river
field survey
thinning
herbivore
landscape position

Cite this

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title = "Forest structure, flooding and grazing predict understorey composition of floodplain forests in southeastern Australia",
abstract = "Most floodplains have been drastically altered by vegetation clearance and river regulation for human needs. In the mid-latitudes, these degraded ecosystems now face the formidable challenge of rapid warming and drying of climates. If the plant diversity of floodplain forests is to be maintained under future climates, their management must be informed by an understanding of how anthropogenic stressors and environmental gradients shape these ecosystems. We used a field survey to examine the potential drivers (forest structure, flooding and anthropogenic disturbance e.g. grazing and logging) of species richness and composition of Eucalyptus camaldulensis floodplain forests in southeastern Australia. Ninety–three stands were surveyed over 15,500 ha of forest, covering a representative range of forest structures and landscape positions, on a mesic and a semi-arid floodplain. Forest structure was an important predictor of the richness and composition of the understorey of river red gum forests on both floodplains. In particular, richness of native species was associated negatively with increasing canopy cover. On the semi-arid floodplain, where there was recent flooding and grazing, these disturbances were also associated with changes in understorey composition. Recent flooding was associated positively with native species richness, with flooded stands having twice the number of native species found in unflooded stands. Recent grazing was associated with an increase in species richness, which may reflect the concentration of herbivores around flooded areas. Targeted thinning to increase structural diversity among stands may temporarily enhance habitat heterogeneity and plant diversity of floodplain forests. If a diverse, native floodplain forest community is to be sustained in these landscapes, management must include regular flooding that approximates the diversity of historical flooding regimes.",
keywords = "Biodiversity, Eucalyptus camaldulensis, Exotic weeds, Flooding, Forest dieback, Grazing.",
author = "Gillis Horner and Shaun Cunningham and Jim THOMSON and Baker, {Patrick J.} and {MAC NALLY}, Ralph",
year = "2012",
doi = "10.1016/j.foreco.2012.08.023",
language = "English",
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pages = "148--158",
journal = "Forest Ecology and Management",
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Forest structure, flooding and grazing predict understorey composition of floodplain forests in southeastern Australia. / Horner, Gillis; Cunningham, Shaun; THOMSON, Jim; Baker, Patrick J.; MAC NALLY, Ralph.

In: Forest Ecology and Management, Vol. 286, 2012, p. 148-158.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Forest structure, flooding and grazing predict understorey composition of floodplain forests in southeastern Australia

AU - Horner, Gillis

AU - Cunningham, Shaun

AU - THOMSON, Jim

AU - Baker, Patrick J.

AU - MAC NALLY, Ralph

PY - 2012

Y1 - 2012

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KW - Biodiversity

KW - Eucalyptus camaldulensis

KW - Exotic weeds

KW - Flooding

KW - Forest dieback

KW - Grazing.

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DO - 10.1016/j.foreco.2012.08.023

M3 - Article

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SP - 148

EP - 158

JO - Forest Ecology and Management

JF - Forest Ecology and Management

SN - 0378-1127

ER -