Charles Darwin University

CDU eSpace
Institutional Repository

 
CDU Staff and Student only
 

Rain forest invasion of eucalypt-dominated woodland savanna, Iron Range, north-eastern Australia: II. Rates of landscape change

Russell-Smith, Jeremy, Stanton, P. J., Edwards, Andrew C. and Whitehead, Peter J. (2004). Rain forest invasion of eucalypt-dominated woodland savanna, Iron Range, north-eastern Australia: II. Rates of landscape change. Journal of Biogeography,31(8):1305-1316.

Document type: Journal Article
Citation counts: Scopus Citation Count Cited 38 times in Scopus Article | Citations

Google Scholar Search Google Scholar

Title Rain forest invasion of eucalypt-dominated woodland savanna, Iron Range, north-eastern Australia: II. Rates of landscape change
Author Russell-Smith, Jeremy
Stanton, P. J.
Edwards, Andrew C.
Whitehead, Peter J.
Journal Name Journal of Biogeography
Publication Date 2004
Volume Number 31
Issue Number 8
ISSN 0305-0270   (check CDU catalogue  open catalogue search in new window)
Scopus ID 2-s2.0-3543089312
Start Page 1305
End Page 1316
Total Pages 12
Place of Publication Oxford
Publisher Blackwell
Field of Research 0403 - Geology
0406 - Physical Geography and Environmental Geoscience
HERDC Category C1 - Journal Article (DEST)
Abstract Aim To explore rates of rain forest expansion and associated ecological correlates in Eucalyptus-dominated woodland savanna vegetation in north-eastern Australia, over the period 1943-91. Location Iron Range National Park and environs, north-east Queensland, Australia. This remote region supports probably the largest extent of lowland (< 300 m) rain forest extant in Australia. Rainfall (c. 1700 mm p.a.) occurs mostly between November and June, with some rain typically occurring even in the driest months July-October. Methods Interpretation of change in lowland rain forest vegetation cover was undertaken for a 140 km(2) area comprising complex vegetation, geology and physiography using available air photos (1943, 1970 and 1991). A GIS database was assembled comprising rain forest extent for the three time periods, geology, elevation, slope, aspect, proximity to streams and roads. Using standard GIS procedures, a sample of 6996 10 x 10 m cells (0.5% of study area) was selected randomly and attributed for vegetation structure (rain forest and non-rain forest), and landscape features. Associations of rain forest expansion with landscape features were examined with logistic regression using the subset of cells that had changed from other vegetation types to rain forest, and remained rain forest over the assessment period, and comparing them with cells that showed no change from their original, non-rain forest condition. Results Rain forest in the air photo study area increased from 45 km(2) in 1943 to 78.1 km(2) by 1970, and to 82.6 km(2) by 1991. Rainfall (and atmospheric CO2 concentration) was markedly lower in the first assessment period (1943-70). Modelled rates of rain forest invasion differed predominantly with respect to substrate type, occurring faster on substrates possessing better moisture retention properties, and across all elevation classes. Greatest expansion, at least in the first assessment period, occurred on the most inherently infertile substrates. Expansion was little constrained by slope, aspect and proximity to streams and roads. On schist substrates, probability of invasion remained high (> 60%) over distances up to 1500 m from mature rain forest margins; on less favourable substrates (diorite, granites), probability of expansion was negligible at sites more than 400 m from mature margins. Main conclusions (i) Rain forest expansion was associated primarily with release from burning pressure from c. the 1920s, following major disruption of customary Aboriginal lifestyles including hunting and burning practices. (ii) Decadal-scale expansion of rain forest at Iron Range supports extensive observations from the palaeoecological literature concerning rapid rain forest invasion under conducive environmental conditions. (iii) The generality of these substrate-mediated observations requires further testing, especially given that landscape-scale rain forest invasion of sclerophyll-dominated communities is reported from other regions of north-eastern Australia.
Keywords rain forest
tropical rain forest
eucalyptus
frugivore
dispersal
succession
expansion
margin extension
nucleation
irruption
tropical dry forest
northeastern queensland
fire protection
pollen record
vegetation
expansion
conservation
quaternary
dynamics
boundary
DOI http://dx.doi.org/10.1111/j.1365-2699.2004.01070.x   (check subscription with CDU E-Gateway service for CDU Staff and Students  check subscription with CDU E-Gateway in new window)
 
Versions
Version Filter Type
Access Statistics: 55 Abstract Views  -  Detailed Statistics
Created: Wed, 28 Nov 2007, 14:16:08 CST