Linear Correlation/Regression Analysis 

 OF Forestry Models, Risk Assessment, 

 AND Water Quality and Fisheries Data 



By Dean Simcek,^ Elizabeth Hill,^ F. Richard Hauer,^ John Fraley/ 

 Thomas Weaver,^ Don Potts,^ and Steve Tralles^ 



Introduction 



Animportantaspectof thecooperative study 

 was to determine whether there are meaningful, 

 quantitative linkages between the type and in- 

 tensity of forest management activities within a 

 watershed and measured effects to the stream 

 ecosystem. Some of the nine previous studies 

 were designed to investigate quantitative or 

 qualitative water quality or fisheries habitat 

 monitoring parameters. Other studies applied 

 modeling procedures to test their validity in the 

 Flathead Basin. However none of the studies 

 focused on directly linking computer generated 

 predictions to the measured field parameters. 

 We designed Module J to compare computer 

 model predicted effects of timber harvest di- 

 rectly to actual quantitative and qualitative water 

 quality or fisheries habitat parameters. 



Several state-of-the-art watershed computer 

 models are used in modem forestry to predict 

 changes in stream flow volume, regime, and 

 sediment yields from proposed forest manage- 

 ment activities. Different watershed models 

 examine various parameters using a number of 

 methods to predict potential changes in the 

 aquatic ecosystem. The Sequoia model (as dis- 

 cussed in Module H), is an index of cumulative 

 disturbed areas. The procedure assumes that 

 disturbance from all timber harvest-related ac- 

 tivities recovers within ten years except for 

 roads, trails, recreation, and administrative sites 



which never recover. The Module H study team 

 developed Sequoia CRA (Cumulative Runoff 

 Acreage) on the 28 fishery watersheds investi- 

 gated in Module D. 



Currently the Flathead National Forest and 

 the Department of State Lands use similar com- 

 puter models to predict water yield increase. 

 These models are based on an Equivalent 

 Clearcut Area (EC A) concept — that is, an 

 increase in average annual water yield will 

 occur following removal of trees from a site. 

 (As water yield increases, the potential for 

 streambank erosion increases. As the trees grow 



'Dean Sirucek is aForest Soil Scientist with the 

 Flathead National Forest in Kalispell, Montana. 



^Eli2abeth Hill is a Forester with the Flathead 

 National Forest in Kalispell, Montana. 



'Dr. F. Richard Hauer is a Research Associate 

 Professor with the Flathead Lake Biological Station 

 in Poison, Montana. 



*John Fraley was a Fisheries Biologist with 

 theMontana Department of Fish, Wildlife and Parks 

 in Kalispell, Montana. 



Thomas Weaver is a Fisheries Officer with the 

 Montana Department of Fish, Wildlife and Parks in 

 Kalispell, Montana. 



'Dr. Don Potts is a Professor with the Univer- 

 sity of Montana School of Forestry in Missoula, 

 Montana. 



'Steve Tralles is an Environmental Specialist 

 with the Water Quality Bureau of the Montana 

 Department of Health and Environmental Sciences 

 in Helena, Montana. 



Flathead Basin Cooperative Program Final Report 



Page 127 



