Problems of placing boundaries on ecological continua - options for a workable national rainforest definition in Australia

Lynch, A. Jasmyn J.; Neldner, Victor J.

doi:10.1071/bt97022

Cited by 18 publications

(10 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…), but at least it provides a yardstick – there is no other such listing available. There is a gradation from obligate rainforest species to those that occur mostly in rainforest but are present also (in less abundance) in open forest, and it is something of an artifice to cut this continuity, especially so as the very definition of rainforest may be extremely slippery (Bowman 2000, 2001; Hill 2000; Lynch & Neldner 2000; Neldner & Lynch 2001).…”

Section: Discussionmentioning

confidence: 99%

Response of vegetation and vertebrate fauna to 23 years of fire exclusion in a tropical Eucalyptus open forest, Northern Territory, Australia

Woinarski¹,

Risler²,

Kean³

2004

Austral Ecology

206

View full text Add to dashboard Cite

This opportunistic study compares the vegetation, fuel loads and vertebrate fauna of part of a 120-ha block of tropical open forest protected from fire for 23 years, and an adjacent block burnt annually over this period. Total fuel loads did not differ significantly between the unburnt and annually burnt sites, but their composition was markedly different, with far less grassy fuel, but far more litter fuel, in the unburnt block. There were major differences between treatments in the composition of trees and shrubs, manifest particularly in the number of stems. There was no overall difference in plant species richness between the two treatments, but richness of woody species was far higher in the unburnt treatment, and of annual and perennial grasses, and perennial herbs in the annually burnt treatment. Change in plant species composition from annually burnt to unburnt treatment was directional, in that there was a far higher representation of rainforest-associated species (with the percentage of woody stems attributable to 'rainforest' species increasing from 24% of all species in the annually burnt treatment to 43% in the unburnt treatment, that of basal area from 9% to 30%, that of species richness from 8% to 17%, and that of cover from 12 to 47%). The vertebrate species composition varied significantly between treatments, but there was relatively little difference in species richness (other than for a slightly richer reptile fauna in the unburnt treatment). Again, there was a tendency for species that were more common in the unburnt treatment to be rainforest-associated species. The results from this study suggest that there is a sizeable and distinct set of species that are associated with relatively long-unburnt environments, and hence that are strongly disadvantaged under contemporary fire regimes. We suggest that such species need to be better accommodated by fire management through strategic reductions in the frequency of burning.

show abstract

Section: Discussionmentioning

confidence: 99%

Response of vegetation and vertebrate fauna to 23 years of fire exclusion in a tropical Eucalyptus open forest, Northern Territory, Australia

Woinarski¹,

Risler²,

Kean³

2004

Austral Ecology

206

View full text Add to dashboard Cite

show abstract

“…3). This rule‐based approach is significant, at least in the Australian context, because standardized definitions of vegetation types and particularly ‘rain forest’ are mired in controversy (Bowman, 2000; Lynch & Neldner, 2000). Furthermore, in the monsoon tropics many tree species can occur in a wide variety of vegetation types, making neat and absolute dichotomization of ‘rain forest’ and ‘non‐rain forest’ species impossible (e.g.…”

Section: Discussionmentioning

confidence: 99%

Forest expansion and grassland contraction within a Eucalyptus savanna matrix between 1941 and 1994 at Litchfield National Park in the Australian monsoon tropics

Bowman¹,

Walsh²,

Milne

2001

Global Ecology and Biogeography

123

View full text Add to dashboard Cite

Analysis of digitized aerial photographs taken in 1941 and 1994, using image processing and geographical information system technology, enabled the quantification of change in the coverage of forest and grassland patches that occur within a Eucalyptus savanna matrix in a subcoastal region of the Australian monsoon tropics. The 3058 ha study area was orientated along a low escarpment that separated a sandstone plateau from lowlands that comprised 58% and 42% of the area, respectively. In the 53‐year period, humans modified less than 1% of the study area, primarily for road building, and primarily in savanna areas. More than 85% of the study area at both sample times was covered by savanna. However, over the same period, the forest coverage increased from 5.03% to 9.91% of the study area and coverage of grassland decreased from 6.70% to 2.47%. The aerial photography also showed that tree density in the savanna had increased, although this was not assessed quantitatively. There was an increase in the number of forest patches from 116 to 142. The number of grassland patches decreased (particularly those > 1 ha) from 87 to 59, although the size class distribution of forest and grassland patches was statistically similar for both sample times. A 50‐m GIS buffer was used to distinguish creek‐lines environments from surrounding catchments. Using this criterion, 14% of the study area was classified as plateau creek‐lines and 9% lowland creek‐lines. Although the expansion of forest and loss of grassland varied significantly amongst catchment and creek‐lines on the plateau and lowlands, the 1941 rank order of coverage of each vegetation type was maintained in these four landscape categories in 1994. In both years the greatest extent of forest and grassland occurred on the lowland catchments, despite their accounting for only one‐third of the study area. Transition matrices for vegetation change among the four landscape categories demonstrated that, unlike the other vegetation types, grasslands, particularly on the plateau, had a low probability of remaining unchanged during the study period. The cause(s) of the overall increase of woody biomass across the topographic and edaphic gradient remains unclear but may be related to a period of increased rainfall since the 1970s, as well as to the cessation of Aboriginal landscape burning at the beginning of the study period.

show abstract

“…2005; Campbell & Clarke 2006). Rainforest plants may be defined as species not dependent on fire for successful regeneration (Lynch & Neldner 2000), although abundant recruitment of new plants via seedlings and root‐coppicing after fire has been documented (Stocker 1981; Unwin 1983; Williams 2000).…”

Section: Introductionmentioning

confidence: 99%

Mechanisms of rainforest persistence and recruitment in frequently burnt wet tropical eucalypt forests

Williams¹,

Parsons²,

Jensen³

et al. 2011

Austral Ecology

View full text Add to dashboard Cite

The role of fire in governing rainforest-eucalypt forest ecotone dynamics is of theoretical interest and has conservation management implications. Several eucalypt forests in the Wet Tropics of Australia have an endangered status due to extensive conversion to rainforest. Rainforest plants are known to survive occasional low intensity fires in the eucalypt forest ecotone. However, the ability of rainforest plants to survive frequent fires remains untested. The timing of rainforest expansion is also a subject of interest, and is generally considered to be delayed until fire has been absent for several years. We used 14 years of data collected across 13 plots in the Wet Tropics of north-eastern Australia to test predictions regarding rainforest seedling recruitment and post-fire regenerative capacity.The 13 plots received different numbers of fires, between zero and five, over the 14-year study. The recruitment of new rainforest plants in the ecotone was most abundant in the initial year after fire. If this post-fire pulse of recruitment is left undisturbed, it can facilitate the subsequent germination of additional rainforest species. The removal of grass cover, whether temporarily in the immediate post-fire environment or once a developing rainforest mid strata shades out grasses, appears crucial to abundant rainforest recruitment. A variety of tropical rainforest species can persist under a frequent fire regime through resprouting. The difference in the mode of resprouting, between ground-level coppicing rainforest plants and canopy resprouting eucalypt forest trees, is the critical mechanism that causes regular fire to maintain an open structure in eucalypt forests. The inability of rainforest species to maintain their height when fires fully scorch their crowns, temporarily resets the forest's open structure and delays the rainforest's ability to dominate through shading out grasses to transform the ecosystem into a closed forest.

show abstract

Problems of placing boundaries on ecological continua - options for a workable national rainforest definition in Australia

Cited by 18 publications

References 30 publications

Response of vegetation and vertebrate fauna to 23 years of fire exclusion in a tropical Eucalyptus open forest, Northern Territory, Australia

Response of vegetation and vertebrate fauna to 23 years of fire exclusion in a tropical Eucalyptus open forest, Northern Territory, Australia

Forest expansion and grassland contraction within a Eucalyptus savanna matrix between 1941 and 1994 at Litchfield National Park in the Australian monsoon tropics

Mechanisms of rainforest persistence and recruitment in frequently burnt wet tropical eucalypt forests

Contact Info

Product

Resources

About