Relatively few evaluations of aquatic macroinvertebrate and fish communities have been published in peer-reviewed literature detailing the effect of varying residual basal area (RBA) after timber harvesting in riparian buffers. Our analysis investigated the effects of partial harvesting within riparian buffers on aquatic macroinvertebrate and fish communities in small streams from two experiments in northern Minnesota northern hardwood-aspen forests. Each experiment evaluated partial harvesting within riparian buffers. In both experiments, benthic macroinvertebrates and fish were collected 1 year prior to harvest and in each of 3 years after harvest. We observed interannual variation for the macroinvertebrate abundance, diversity and taxon richness in the single-basin study and abundance and diversity in the multiple-basin study, but few effects related to harvest treatments in either study. However, interannual variation was not evident in the fish communities and we detected no significant changes in the stream fish communities associated with partially harvested riparian buffers in either study. This would suggest that timber harvesting in riparian management zones along reaches ≤200 m in length on both sides of the stream that retains RBA ≥ 12.4 ± 1.3 m2 ha-1 or on a single side of the stream that retains RBA ≥ 8.7 ± 1.6 m2 ha-1 may be adequate to protect macroinvertebrate and fish communities in our Minnesota study systems given these specific timber harvesting techniques.
Bibliographical noteFunding Information:
We thank Matthew Ihnken, Robert Dodd, and Scott Haire for assistance in the field and the laboratory. Brian Palik, Jim Perry, and Dave Zumeta provided helpful comments on an earlier draft of this manuscript. Brian Palik and personnel at the US Forest Service Northern Research Station were instrumental in setting up the studies. Partial funding for this project was provided by the Minnesota Department of Natural Resources Section of Fisheries , Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR), Minnesota Forest Resources Council, and Minnesota Trout Unlimited. Reference to trade names does not imply endorsement by authors or the U.S. Government.
- Residual basal area
- Temporal variation
- Timber harvest