PS 40-113 - Effects of fire management on the structure and function of aquatic ecosystems

Abstract: With prescribed fire more frequently being used as a forest management tool, understanding its impacts on ecosystem structure and functioning is vital to making ecologically informed management decisions. Many forest ecosystems are interconnected to aquatic ecosystems through the exchange of energy and resources. Little is known about how prescribed burning impacts aquatic systems linked to forests. To better make future fire-management decisions, understanding not just how forests are affected through burning, but also how linked aquatic systems are responding to this management process will be necessary. Our research goals are to compare how aquatic systems respond to forest fires. Specifically, we asked: (1) how is aquatic community composition and structure affected by forest burning? and (2) how are key ecosystem processes such as organic matter decomposition impacted by forest burning? To answer these questions we used artificial aquatic microcosms to experimentally replicate natural aquatic ecosystems. The microcosms were placed within forest plots, which had sections recently burned as well as fire-excluded sections.

Results/

Conclusions: Our results showed that community structure and ecosystem function varied between burned and not burned forests. Burned sites generally exhibited lower decomposition rates, lower average abundance and lower average diversity. Our results suggest that the impact of prescribed fire as a management tool affects community structure and ecosystem functioning of terrestrially-linked aquatic systems, and that these responses could be dependent on factors such as the fire-history of the managed forest. This information could prove invaluable for forest managers who want to make ecologically sound prescribed burning decisions.