Kanuka on dunes
Structure and dynamics of kanuka (Kunzea ericoides var. ericoides) heaths on sand dunes in Bay of Plenty, New Zealand New Zealand Journal of Botany, 1994, Vol . 32 : 441–452 © The Royal Society of New Zealand 1994
Filename: smalettree.pdf ( view )
Size: 993.6 KB
Document type: application/pdf ( )
Abstract The structure, composition, and dynamics
of a rare coastal community, kanuka (Kunze a
ericoides var . ericoides) shrub- and tree-heaths on
sand dunes, were studied on Whale Island and at
Thornton, in Bay of Plenty . Both multi-stemmed,
semi-prostrate and erect kanuka is present in
virtually pure stands on largely unconsolidated dunes
on Whale Island, and multi-stemmed, semi-prostrate
kanuka in nearly pure stands on consolidated dunes
at Thornton . This and other studies indicate that lack
of competition (i.e. establishment at low densities)
is primarily responsible for the multi-stemmed habit ,
but interacting environmental (exposure, drought )
and genetic factors may also play a part. All communities
are floristically poor compared with othe r
woody communities in New Zealand, with onl y
widespread species present and a large proportion o f
adventives . Mean annual diameter growth was
3 .0 mm/yr at Whale Island and 2.8 mm/yr at
Thornton; mean annual height growth ranged from
29.8 cm/yr in younger stands (6–18 years) on Whal e
Island to 10.2 cm/yr in older stands (27–34 years) ,
and 10 .5 cm/yr at Thornton . All populations had
regenerated in cohorts over periods ranging from c . 5
to c . 35 years, after fire removed previous vegetatio n
or sand became sufficiently stable for seedlings t o
establish . Kanuka may replace itself indefinitely on
unstable dunes on Whale Island, where the community
is still expanding, and at Thornton, which is
isolated from seed sources of potential successors .
Keywords kanuka; Kunzea ericoides ; sand dunes ;
ecology ; succession
