This project addresses the following theme and funding priority topic of the sustainability program: 1.0 Ecosystem structure, function, and processes, and biodiversity related to forest management 1.1 Riparian ecology and management of small streams 3. Significance of small streams as sources of material and energy to downstream reaches Concern has been expressed by both DFO and BC WLAP that clearcut logging of headwater streams may be depriving downstream fish populations of food. The contributions of high elevation streams in the Engelmann Spruce Sub-alpine Fir (ESSF) forest to river ecosystems with respect to diversity and abundance of invertebrates, and quantity of detritus and dissolved organic matter is not well known. The results of this project will address this knowledge gap by assessing the contribution of fish food and organic matter from fishless headwater streams to lower, fish-bearing streams. Forest managers, especially under a results based code, need a high degree of certainty to ensure desired ecosystem characteristics are being maintained. Our partners (Weyerhaeuser, Tolko and Canfor) have expressed an imminent need for knowledge of the functions of these small streams and data that either supports the current forest practices or indicates a need for alternate strategies. Our deliverables will reduce this uncertainty for managers defining parameters of sustainable forest management and provide recommendations for improving policy on riparian buffer zones. The objectives of this research project are to: 1. Evaluate the effectiveness of the current riparian management practice of a no-machine zone by determining if clearcut logging of headwater streams in the interior of BC reduces the export of aquatic invertebrates, detritus and DOC. 2. Quantify the contribution that fishless, headwater streams make to downstream fish-bearing reaches in terms of aquatic invertebrates, detritus and DOC for the stream food web. 3. Determine the effect of high/low season flows on DOC. To achieve these objectives we proposed two strategies; a short term and a long term approach. The short term approach includes the 2003/2004 (FII funded) and the current year?s research examining multiple control and clearcut streams. The long-term approach will examine streams both before logging (pre-cut) and after logging (post-cut). During 2004/2005, streams designated by our industry partners to be harvested (clearcut) in 2005-2007 were sampled, providing us with pre-logging data. Through continued consultation with our industry partners, we plan to sample 4 pre-cut and 4 control streams in both the Damfino and Bone Creek study areas in 2005/2006. Depending on our partners? harvesting plans, some of our pre-cut sites from the previous year may have been logged. In this case these harvested sites will be sampled as post-cuts. Additional study sites will be selected from an area west of Clearwater (Canfor) or east of Barrier (Tolko). The additional study sites will provide us with a total of 32 streams (16 pre-cuts and 16 controls), with all sites sampled in triplicate. In 2006/2007, we will sample post-cut and control streams.
Heise, Brian A.. 2007. Effects of logging on export of organic matter from headwater streams. Forest Investment Account (FIA) - Forest Science Program. Forest Investment Account Report. FIA2007MR397