Fire Research » Fire Ecology & Fire Effects

Fire Ecology and Fire Effects

EMEND - Ecosystem Management by Emulating Natural Disturbance

Introduction

The Ecosystem Management by Emulating Natural Disturbance (EMEND) experiment, in northwestern Alberta, is a multifaceted research project aimed at determining the effect of harvesting disturbance on the boreal forest. The project was developed to investigate the significance of residual forest structure on ecosystem function after fire and harvest in the boreal forest. Work at EMEND also investigates trade-offs among biodiversity, productivity, and other aspects of ecological function. The EMEND project is one of the largest fully replicated natural forest disturbance experiments in North America

The fire science working group at the Northern Forestry Centre in Edmonton has been part of a larger team working toward delivering prescribed fire treatments since the beginning of the EMEND experiment.

Fire Prescription

Prescribed fire can be used to accomplish particular goals and objectives. In this context, a fire prescription is developed using available prediction tools including the Canadian Forest Fire Weather Index System and the Canadian Forest Fire Behavior Prediction System. These tools are used to determine the appropriate weather conditions to achieve a fuel-specific fire intensity that is likely to accomplish the goals and objectives of the fire treatment. These weather conditions, expressed as fire weather codes and indices, become the fire prescription.

Fire Weather Monitoring

Fire weather monitoring is used to determine when the EMEND site is within the fire prescription. Collection of daily meteorological data, including relative humidity, wind velocity and direction, temperature, and 24-hour precipitation, enables the determination of various fire weather codes and indices, which are then compared to the fire prescription.

Measuring Fire Characteristics

To understand the characteristics of a fire once it has been applied, both prefire and postfire sampling are necessary. Sampling is carried out to measure the amount of woody fuel present on the forest floor and the amount of organic material or duff present in the forest. The amount of fuel consumed by the fire is estimated as the difference between prefire and postfire measurements. During the prescribed fire, rate of spread is estimated by timing the spread of fire over a known distance. The fire intensity can be estimated from all of these measurements according to Byram's fire intensity equation.

I = hwr

where I is the fire intensity, h is the heat of combustion, w is the mass of fuels consumed by the fire as determined by pre- and post-fire sampling, and r is the fire's rate of spread.

Fire intensity can then be related to the numerous ecological and natural disturbance studies being conducted within the EMEND experiment.

Project Funding

The EMEND experiment is primarily funded by Daishowa-Marubeni International Ltd., Canadian Forest Products, Sustainable Forest Managagement Network of the National Centres of Excellence, Manning Diversified Forest Products, the Weyerhaeuser Company, and the Forest Resource Improvement Association of Alberta. In-kind support from Alberta Sustainable Resource Development is received for completion of prescribed fires.

Questions related to prescribed fire at the EMEND experiment can be directed to Peter Bothwell Pete.Bothwell@nrcan.gc.ca.

For other information related to the EMEND project, visit the EMEND Web site.