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degree of vegetation removal and proximity to streams, burning and 

 increased sedimentation. Clearcutting practices have been shown to cause 

 increases in stream temperature (12,15,41,42,45,46). Vegetation removal 

 adjacent to streams can increase solar radiation, thereby raising stream 

 temperatures (6,12,19,42). Fires, either prescribed slash burning or 

 natural, may affect stream temperatures due to vegetation removal and/or 

 the actual heat generated by the fire (10,41,45). When forestry practices 

 generate increased sediment loads and turbidity, stream temperature may 

 also increase due to the higher absorption capacity of the turbid waters. 



There has been no research done in Montana that relates stream temperature 

 fluctuations with silvicultural practices. 



E. Nutrients 



Forestry practices may result in nutrient losses from soils which in 

 turn cause increased levels of nutrients in stream water chemistry. Such 

 changes may affect the aquatic life communities of streams, as well as 

 degrade soil fertility. Harvesting methods, prescribed burning, and 

 road construction are activities which may influence nutrient cycling. 



Clearcut harvesting has been correlated with high nutrient levels in streams 

 (8,11,26,29). Nutrient losses may be accelerated depending upon soil 

 types or prescribed burning in the clearcut area. 



It has been demonstrated that fire can release many soil nutrients, leading 

 to increased nutrient levels in streams (11,22,28,35,61,64,70). Such 

 effects and their duration depend upon the type of fire (natural, broadcast 

 burn, pile burn, etc.) and the rate of revegetation. 



