Gap-phase dynamics and coexistence of a long-lived pioneer and shade-tolerant tree species in the canopy of an old-growth coastal temperate rain forest of Chiloé Island, Chile

$48.00 plus tax (Refund Policy)

Download / Buy Article:

Abstract:

Summary Aim 

A major question with regard to the ecology of temperate rain forests in south-central Chile is how pioneer and shade-tolerant tree species coexist in old-growth forests. We explored the correspondence between tree regeneration dynamics and life-history traits to explain the coexistence of these two functional types in stands apparently representing a non-equilibrium mixture. Location 

This study was conducted in northern Chiloé Island, Chile (41.6° S, 73.9° W) in a temperate coastal rain forest with no evidence of stand disruption by human impact. Methods 

We assessed stand structure by sampling all stems within two 50 × 20 m and four 5 × 100 m plots. A 600-m long transect, with 20 uniformly spaced sampling points, was used to quantify seedling and sapling densities, obtain increment cores, and randomly select 10 tree-fall gaps. We used tree-ring analysis to assess establishment periods and to relate the influences of disturbances to the regeneration dynamics of the main canopy species. Results 

Canopy emergent tree species were the long-lived pioneer Eucryphia cordifolia and the shade-tolerant Aextoxicon punctatum. Shade-tolerant species such as Laureliopsis philippiana and several species of Myrtaceae occupied the main canopy. The stem diameter distribution for E. cordifolia was distinctly unimodal, while for A. punctatum it was multi-modal, with all age classes represented. Myrtaceae accounted for most of the small trees. Most tree seedlings and saplings occurred beneath canopy gaps. Based on tree-ring counts, the largest individuals of A. punctatum and E. cordifolia had minimum ages estimated to be > 350 years and > 286 years, respectively. Shade-tolerant Myrtaceae species and L. philippiana had shorter life spans (< 200 years). Most growth releases, regardless of tree species, were moderate and have occurred continuously since 1750. Main conclusions 

We suggest that this coastal forest has remained largely free of stand-disrupting disturbances for at least 450 years, without substantial changes in canopy composition. Release patterns are consistent with this hypothesis and suggest that the disturbance regime is dominated by individual tree-fall gaps, with sporadic multiple tree falls. Long life spans, maximum height and differences in shade tolerance provide a basis for understanding the long-term coexistence of pioneer and shade-tolerant tree species in this coastal, old-growth rain forest, despite the rarity of major disturbances.

Keywords: Chile; dendroecology; disturbance regime; regeneration modes; shade tolerance; temperate rain forest; tree life history; tree-fall gap dynamics; tree-species coexistence

Document Type: Research Article

DOI: http://dx.doi.org/10.1111/j.1365-2699.2008.01908.x

Affiliations: 1: Centro de Estudios Cuaternarios (CEQUA), Universidad de Magallanes, Punta Arenas, Chile 2: Laboratorio de Dendrocronología, Facultad de Ciencias Forestales, Universidad Austral de Chile, Valdivia, Chile 3: Sveriges lantbruksuniversitet SLU, Sweden

Publication date: September 1, 2008

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more