Small Scale Stream Restoration Simulation and Response on Stream Temperature Using a Physically Based Temperature Model

Stream temperature is a first order control on fish habitat and is an indicator of threshold behaviors of many cold water fish species including salmon. In-stream biological, chemical, and physical processes such as nutrient cycling, aquatic species metabolic rates, and physiology are influenced by stream temperatures. Solar radiation is a driving force on stream temperature. Recent research on streamside riparian restoration efforts have been focused on the effects of solar radiation shading as an effective method to reduce stream temperature. Distributed Temperature Sensing (DTS) is used along with SensorScope technology for meteorological inputs into a physically based model for stream temperatures in a small stream in rural Switzerland. Model outputs show that changes in current land-use management practices that primarily focus on large shade trees, such as the use of in-stream bur-reed (Sparganium), can lead to lower mean stream temperatures and improve fish habitat. Results suggest viable alternatives for small streams where riparian zone land availability is scarce and/or where large scale restoration efforts are cost prohibitive or not practical.