A graduating essay by Yu Chen submitted for a BSc at UBC.
Abstract: Stream sedimentation issues resulting from forestry practices are prevalent in the province of British Columbia. The impacts of riparian forest harvesting on the sediment regime of streams are of concern because of extensive commercial use of forest resources in BC. Forestry practices can alter the natural sediment balance and lead to abnormally high rates of sediment input resulting in increased concentrations of sediment in the water body and increased deposition of sediment on the stream bottom. The increase of sediment yield driven by forestry operations can reduce the storage capacity of reservoirs and degrade the water quality for human drinking, industrial, and recreational uses. Sediment inputs that exceed the background level and turbidity can also increase the risk to the survival and the integrity of aquatic ecosystems. Riparian forested areas in both coastal and interior plateau forest watersheds need careful considerations of riparian buffers and best management practices to avoid excessive sediment delivery into stream networks. Also, quantitative studies need to be conducted to compare different harvesting methods and provide forest management planner better suggestions to achieve both economic and environmental objectives. In general, a holistic approach is required to control sediment production across different landscapes. What’s more, a better understanding of the interaction between sediment dynamics and forest harvesting and continuous implementation of best management practices will result in fewer problems.