Niche differentiation and regeneration in the seasonally flooded Melaleuca forests of northern Australia
journal contribution
posted on 2023-05-17, 05:59authored byFranklin, DC, Brocklehurst, PS, Lynch, D, David BowmanDavid Bowman
Gallery and floodplain forests in monsoonal northern Australia are mostly sclerophyllous and dominated by five closely related species of Melaleuca (Myrtaceae) amongst which niche differentiation is unclear. We present a floristic and environmental analysis of ‘the flooded forest’ using data from 340 plots distributed across 450 000 km2 of the Top End of the Northern Territory. Melaleuca argentea was confined to streams and occurred on sandier substrates, whereas M. cajuputi mostly occurred in the near-coastal lowlands on clay soils. The greater basal area of M. cajuputi suggests an association with productive sites. Melaleuca dealbata, M. viridiflora and M. leucadendra occurred on a wide range of soils. More deeply floodprone sites were occupied by M. argentea and M. leucadendra along streams and by M. leucadendra and M. cajuputi on floodplains and in swamps. A general deficiency but occasional abundance of Melaleuca seedlings suggests that regeneration is episodic. Seedlings were more frequent in recently burnt areas and especially where fires had been severe. We propose that Melaleuca forests occur where disturbance by fire and/or floodwater is too great for rain forest to persist, rendering them the wetland analogue to the eucalypts that dominate well-drained portions of the north Australian environment.
History
Publication title
Journal of Tropical Ecology
Volume
23
Issue
4
Pagination
457-467
ISSN
0266-4674
Department/School
School of Natural Sciences
Publisher
Cambridge University Press
Place of publication
United Kingdom
Repository Status
Restricted
Socio-economic Objectives
Assessment and management of freshwater ecosystems