Analysis of continental scale vegetation
cover over the last decade
DECEMBER 2011
PRODUCED BY Sandra Berry, Fenner School of Environment and Society
The Australian National University
FOR the Department of Sustainability, Environment, Water, Population and Communities
ON BEHALF OF the State of the Environment 2011 Committee
Citation
Berry S. Analysis of continental scale vegetation cover over the last decade. Report prepared
for the Australian Government Department of Sustainability, Environment, Water, Population
and Communities on behalf of the State of the Environment 2011 Committee. Canberra:
DSEWPaC, 2011.
© Commonwealth of Australia 2011.
This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no
part may be reproduced by any process without prior written permission from the
Commonwealth. Requests and enquiries concerning reproduction and rights should be
addressed to Department of Sustainability, Environment, Water, Populations and
Communities, Public Affairs, GPO Box 787 Canberra ACT 2601 or email
public.affairs@environment.gov.au
Disclaimer
The views and opinions expressed in this publication are those of the author and do not
necessarily reflect those of the Australian Government or the Minister for Sustainability,
Environment, Water, Population and Communities.
While reasonable efforts have been made to ensure that the contents of this publication are
factually correct, the Commonwealth does not accept responsibility for the accuracy or
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occasioned directly or indirectly through the use of, or reliance on, the contents of this
publication.
Cover image
Fitzroy Bluff, Mornington Station in the Kimberley, WA
Photo by Nick Rains
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Preface
This report was commissioned by the Department of Sustainability, Environment, Water,
Population and Communities to help inform the Australia State of the Environment (SoE)
2011 report.
The Minister for Environment is required, under the Environment Protection and Biodiversity
Conservation Act 1999, to table a report in Parliament every five years on the State of the
Environment.
The Australia State of the Environment (SoE) 2011 report is a substantive, hardcopy report
compiled by an independent committee appointed by the Minister for Environment. The
report is an assessment of the current condition of the Australian environment, the pressures
on it and the drivers of those pressures. It details management initiatives in place to address
environmental concerns and the effectiveness of those initiatives.
The main purpose of SoE 2011 is to provide relevant and useful information on
environmental issues to the public and decision-makers, in order to raise awareness and
support more informed environmental management decisions that lead to more sustainable
use and effective conservation of environmental assets.
The 2011 SoE report, commissioned technical reports and other supplementary products are
available online at www.environment.gov.au/soe.
Australia ■ State of the Environment 2011 Supplementary information
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Analysis of continental scale vegetation cover over the last decade
Analysis of continental scale vegetation cover over the last decade.
Green vegetation cover is an indicator of the health of the landscape, being strongly related to the
capacity of vegetation to assimilate carbon dioxide and energy from sunlight through
photosynthesis. In addition to its role of producing fibre and food, green vegetation cover acts to
modify local climate parameters including the near surface air temperature, humidity, wind, and
cloud formation. It also impacts on the hydrological cycle, intercepting precipitation and transferring
water from the lithosphere to the atmosphere through the process of transpiration that
accompanies photosynthesis.
Data collected by sensors carried on satellites that make regular passes over Australia reveal the
extent to which green vegetation cover (greenness) varies in response to fluctuations in rainfall, and
major disturbances such as wildfires, cyclones and severe storms. Analysis of a ten-year time series
of vegetation greenness calculated from the MODIS 16-day 250 m (MOD13Q1) NDVI product (Paget
and King 2008) reveals the extent of variability over the decade. Comparison of maximum and
minimum between-year mean annual greenness for individual (250 m × 250 m) pixels over the time
series (July 2000 to June 2010), and the years in which these extremes occurred (Figures 1 and 2)
reveals broad-scale patterns of climate (ENSO) effects.
The maximum mean annual greenness over the decade (Figure 1a) indicates the potential for
productivity at the scale of individual(250 m × 250 m) pixels. The highest values occur where the
vegetation cover is rainforest or wet eucalypt forest. There is a strong relationship between the
greenness of natural vegetation and the availability of water for plant growth. Where the natural
vegetation has been thinned or cleared the greenness is reduced. When vegetation is cleared or
thinned, evergreen cover is removed. Although land under agriculture may support crops having
dense foliage during the growing season, for much of the year bare soil or dead plant tissues
dominate the surface cover. Consequently the mean annual greenness is reduced below that of
nearby native vegetation. This is evident in Figure 1a in the wheat-growing regions of Australia
(south-western Western Australia, the Eyre and York Peninsulas of South Australia, and western
Victoria and New South Wales). Over much of the eastern half of Australia the maximum greenness
occurred at either the beginning or the end of the decade (Figure 1b). The maximum greenness of
some regions (notably south-eastern Queensland/northern New South Wales, and south-western
Western Australia), however, is distinctly out of phase. In contrast, minimum greenness (Figures 2a
and b) over much of Australia occurred over a range of years from mid-2002 to mid-2008. The
minimum greenness (Figure 2) does not always correspond to the period of most extreme drought.
For example, areas severely burnt by fires in the summer of 2003 in south-eastern Australia, western
Tasmania, and the Great Western Woodlands (eastern goldfields region) of south-western Western
Australia, have minimum greenness for the year 2003-2004.
Whilst Figures 1a and 2a show the range of mean greenness over the annual period, Figure 3 shows
the minimum greenness recorded over the 120 months of the time-series. This represents the
minimum greenness of the evergreen vegetation (mostly trees and shrubs) over the decade. At
some time during the decade much of Australia supported very sparse vegetation cover, or no green
vegetation cover. That is to be expected for agricultural areas following harvest and prior to
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Analysis of continental scale vegetation cover over the last decade
planting. It is also to be expected in the alpine areas where there is snow on the ground for several
weeks during winter. More surprising is the reduction in green cover over the rainforests of tropical
north Queensland. Loss of green foliage in these normally dense forests may have resulted from
water stress, fire or severe wind storms such as Cyclone Larry or any combination of these.
The annual average rainfall for each state over the decade corresponding to the greenness data is
shown in Figure 4. Variability in greenness over the same period at the regional scale (based on IBRA
regions) is summarised in Figure 5. Average rainfall for Tasmania remained high but variable
throughout the decade. For many IBRA regions in Tasmania (Fig 5a) this variability is not reflected in
the greenness as precipitation exceeds potential evaporation. The greenness of most IBRA regions
over Australia, however, broadly tracks the large-scale variability in annual rainfall (Fig 5b-5h).
References and further reading
Berry, S.L., Keith, H., Mackey, B., Brookhouse, M. and Jonson, J. (2010) Green carbon: the role of
natural forests in carbon storage Part 2. Biomass carbon stocks in the Great Western Woodlands
ANU E Press, The Australian National University, Canberra
Berry, S. L. and Roderick, M. L. (2002). Estimating mixtures of leaf functional types using continentalscale satellite and climatic data. Global Ecology and Biogeography 11: 23-40.
Donohue, R.J., McVicar, T.R. and Roderick, M. L. (2009). “Climate-related trends in Australian
vegetation cover as inferred from satellite observations, 1981-2006.” Global Change Biology
15:1025-1039.
Keith, H., Mackey, B., Berry, S., Lindenmayer, D. and Gibbons, P. (2010). Estimating carbon carrying
capacity in natural forest ecosystems across heterogeneous landscapes: addressing sources of error.
Global Change Biology, 16: 2971-2989.
Paget, M. J. and King, E. A. (2008) MODIS land data sets for the Australian region, CSIRO Marine and
Atmospheric Research internal report No. 004, CSIRO Marine and Atmospheric Research, Canberra,
[for further information with regard to this data set, contact: Matt Paget, <matt.paget@csiro.au> or
Edward King, <edward.king@csiro.au>].
Captions to Figures
Figure 1 (a). This map shows the maximum mean annual greenness of 250m x 250m pixels over the
decade July 2000 through June 2010. (b) This map shows the year (July to June) that corresponds to
the year having maximum mean annual greenness.
Figure 2 (a). This map shows the minimum mean annual greenness of 250m x 250m pixels over the
decade July 2000 through June 2010. (b) This map shows the year (July to June) that corresponds to
the year having minimum mean annual greenness.
Figure 3. This map shows the minimum monthly value of greenness over the 120 months of the
time-series. The minimum greenness here is due to the presence of a surface cover of evergreen
vegetation. In alpine regions the evergreen vegetation may be obscured by snow cover.
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Analysis of continental scale vegetation cover over the last decade
Figure 4. Average annual rainfall for the period July 2000 through June 2010. Data source: Bureau of
Meteorology (<http://www.bom.gov.au/cgi-bin/climate/change/timeseries.cgi>). This figure
incorporates climate data that are Copyright Commonwealth of Australia 2009.
Figure 5. Mean annual greenness within IBRA Regions - (a) Tasmania; (b) South-eastern Australia; (c)
Mid-eastern Australia; (d) Northern Queensland; (e) Northern Territory; (f) Central Australia; (g)
Western Australia; (h) Southern Australia.
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Analysis of continental scale vegetation cover over the last decade
Fig 1a.
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Analysis of continental scale vegetation cover over the last decade
Fig 1b
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Analysis of continental scale vegetation cover over the last decade
Fig 2a
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Analysis of continental scale vegetation cover over the last decade
Fig 2b
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Analysis of continental scale vegetation cover over the last decade
Fig 3
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Analysis of continental scale vegetation cover over the last decade
1800
1600
1400
Rainfall mm yr -1
1200
1000
TAS
NT
Qld
800
Vic
NSW
600
WA
SA
400
200
0
Fig 4.
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Analysis of continental scale vegetation cover over the last decade
80
70
60
Greenness (%)
50
15. Tasmanian
Southern Ranges
80. Tasmanian
Northern Slopes
14. Tasmanian
West
11. Ben Lomond
40
85. King
30
16. Tasmanian
Central Highlands
20
13. Tasmanian
South East
12. Tasmanian
Northern Midlands
10
0
Fig 5a. Mean annual greenness within IBRA Regions - Tasmania.
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Analysis of continental scale vegetation cover over the last decade
80
10. South East Corner
70
6. Australian Alps
60
5. South Eastern
Highlands
9. Flinders
Greenness (%)
50
4. South East Coastal
Plain
40
30
20
10
3. Victorian Volcanic
Plain
2. Naracoorte Coastal
Plain
7. NSW South
Western Slopes
8. Riverina
1. Murray Darling
Depression
0
Fig 5b. Mean annual greenness within IBRA Regions - South-eastern Australia
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Analysis of continental scale vegetation cover over the last decade
80
27. NSW North Coast
70
60
Greenness (%)
50
40
30
20. Sydney Basin
74. South Eastern
Queensland
26. New England
Tablelands
23. Nandewar
76. Brigalow Belt
South
22. Brigalow Belt
North
24. Cobar Peneplain
20
17. Darling Riverine
Plains
18. Mulga Lands
10
21. Channel Country
0
25. Broken Hill
Complex
19. Simpson
Strzelecki Dunefields
Fig 5c. Mean annual greenness within IBRA Regions - Mid-eastern Australia
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Analysis of continental scale vegetation cover over the last decade
80
42. Wet Tropics
70
60
Greenness (%)
50
40
43. Central Mackay
Coast
40. Cape York
Peninsula
44. Einasleigh Uplands
46. Gulf Fall and
Uplands
39. Gulf Plains
45. Desert Uplands
38. Mount Isa Inlier
30
20
10
0
Fig 5d. Mean annual greenness within IBRA Regions - Northern Queensland
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Analysis of continental scale vegetation cover over the last decade
80
83. Tiwi Cobourg
70
81. Arnhem Coast
79. Darwin Coastal
60
77. Central Arnhem
Greenness (%)
50
75. Pine Creek
82. Arnhem Plateau
40
73. Daly Basin
72. Gulf Coastal
30
84. Davenport
Murchison Ranges
20
10
0
Fig 5e. Mean annual greenness within IBRA Regions - Northern Territory
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Analysis of continental scale vegetation cover over the last decade
80
50. Sturt Plateau
70
60
Greenness (%)
50
52. Victoria
Bonaparte
51. Ord Victoria
Plain
48. Burt Plain
47. MacDonnell
Ranges
49. Tanami
40
30
20
10
0
Fig 5f. Mean annual greenness within IBRA Regions - Central Australia
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Analysis of continental scale vegetation cover over the last decade
80
62. Warren
70
61. Jarrah Forest
69. Swan Coastal Plain
60
57. Esperance Plains
66. Northern Kimberley
Greenness (%)
50
56. Coolgardie
64. Mallee
67. Geraldton Sandplains
40
58. Dampierland
55. Central Kimberley
30
70. Avon Wheatbelt
71. Yalgoo
20
68. Pilbara
54. Carnarvon
65. Murchison
10
60. Great Sandy Desert
63. Little Sandy Desert
0
59. Gibson Desert
53. Gascoyne
Fig 5g. Mean annual greenness within IBRA Regions - Western Australia
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Analysis of continental scale vegetation cover over the last decade
80
70
37. Kanmantoo
60
35. Eyre Yorke Block
34. Hampton
Greenness (%)
50
40
36. Flinders Lofty
Block
33. Nullarbor
29. Finke
28. Central Ranges
30
20
32. Great Victoria
Desert
31. Gawler
30. Stony Plains
10
0
Fig 5h. Mean annual greenness within IBRA Regions - Southern Australia
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