Category: Ecological Research
Title: Fire histories in ponderosa pine forests of Grand Canyon are well supported: reply to Baker
Author: * Fule, P.Z. , * Heinlein, T.A. , * Covington, W.W.
Subject: Fire history, Grand Canyon, Fire scars, Ponderosa pine (Pinus ponderosa)
Abstract: Fire scars and other paleoecological methods are imperfect proxies for detecting past patterns of fire events. However, calculations of long fire rotations in Grand Canyon ponderosa pine forests by Baker are not convincing in methodology or assumptions compared with fire-scar evidence of frequent surface fires. Patches of severe disturbance are a possible hypothesis to explain the relatively short age structure at the park, where ?12(percent) fewer trees were older than 300 years compared with another unharvested northern Arizona site. However, mapped patterns of old trees as well as the evidence for frequent surface fire from fire scars, charcoal deposition studies, and evolutionary history are more consistent with the dominance of surface fire prior to c. 1880. The most relevant available evidence of fire recurrence at a given point, mean point fire intervals, had median values 16 years at all five study sites, close to filtered composite fire interval statistics (?610 years), but much lower than Bakers calculated fire rotation values (55110 years). The composite fire interval is not a uniquely important statistic or a numerical guideline for management, but one of many lines of evidence underscoring the ecological role of frequent surface fire in ponderosa pine forests.
Source: International Journal of Wildland Fire
Identifier: 15 (439-445)
Publisher: CSIRO, http://www.publish.csiro.au/?nid=114