The impacts of large-scale, low-intensity fires on the forests of continental South-east Asia

Abstract

South-east Asia's tropical forests harbour high levels of species richness and endemism. In continental Southeast Asia strong rainfall seasonality driven by the Asian monsoon lead to ground-fires during the dry season in most years. How these fires influence the region's landscape mosaic of evergreen and deciduous forests and the biodiversity they support is poorly understood. In this paper we report on the impacts of the El Niño-Southern Oscillation-induced 1997-98 fires that burned across much of western Thailand. We compare fire effects in the three common regional forest types -seasonal evergreen (SEG); mixed deciduous (MDF); and deciduous dipterocarp -and use data from a 50-ha study plot to evaluate the impacts of fire on these forests. We found few differences among the forest types. The fires created more large gaps in MDF than the other forest types. The SEG experienced greater fire mortality in the smallest size classes, abundant resprouting, and showed some evidence of lagged mortality among larger trees. The resilience of the SEG to fire and lack of major differences in fire effects among the forest types suggest that infrequent landscape-scale fires may have little effect on biodiversity in the landscape mosaic of seasonal tropical forests of continental South-east Asia.

Large fires and their ecological consequences: introduction to the special issue

“…Crucial impacts of large fires on ecosystems may depend largely on their rate of recurrence as well as on the range of resultant intensity (Baker et al 2008;Bradstock 2008;Gill and Allan 2008;Williams et al 2008;Yates et al 2008). In this regard, Veblen et al (2008) provide striking examples of the degree of change in vegetation that can occur across gradients of Patagonian vegetation.…”

“…Burton et al (2008) highlight the importance of landscape patchiness that results form large fires to ecological complexity in the Boreal forests of Canada. Other papers present and synthesise new results, and illustrate the importance of longterm datasets in addressing the ecological consequences of large fires: Baker et al (2008) with respect to tropical rainforests in south-east Asia, and Williams et al (2008) for Australian alpine landscapes. Changes to many communities that result from individual large fires may be substantial in some communities, yet direct evidence of large scale elimination of biota is lacking.…”

“…Changes to many communities that result from individual large fires may be substantial in some communities, yet direct evidence of large scale elimination of biota is lacking. Biota may therefore vary widely in their resilience to the fire regimes that emerge from the passage of large fires (Baker et al 2008;Keane et al 2008;Veblen et al 2008;Williams et al 2008).…”

Tree mortality following ENSO-associated fires and drought in lowland rain forests of Eastern Nicaragua

“…This vulnerability could be due in part to insufficient protection by its bark (Pinard et al, 1999;van Nieuwstadt, 2002;Eriksson et al, 2003;Cleary and Priadjati, 2005;Baker et al, 2008;Slik et al, 2010) or to the proximity of their root systems to the soil surface (Montoya, 2011). Some of these species are dominant in the mature stages (Slik et al, 2002;Cleary and Priadjati, 2005), but an analysis of the highly diverse plant community assemblage of such ecosystems requires a detailed assessment of the individual species responses to fire as well as to drought (Slik, 2004;Barlow et al, 2003b;Balch et al, 2011).…”

Climate and historical stand dynamics in the tropical pine forests of northern Thailand

“…In addition, these same microclimatic conditions make seasonal tropical forests prone to fire. While fires in seasonal tropical forests are often low-intensity surface fires (Laurance, 2003;Barlow and Peres, 2004), mortality among seedlings is typically high (Baker et al, 2008). Consequently, successful recruitment of trees in seasonal tropical environments may depend on the occurrence of 3-4 years of mild (i.e.…”