CONTENTS 



Page 



INTRODUCTION 1 



DEVELOPMENT OF ASPCON 2 



TRANSFER FUNCTIONS ' 4 



MODEL CALIBRATION 8 



PREDICTED HYDROLOGIC IMPACT OF SUCCESSION . .■ 11 



SUMMARY AND CONCLUSIONS '. 15 



PUBLICATIONS CITED 15 



RESEARCH SUMMARY 



Hydrologic impacts of grass-forb to aspen to conifer succession in the Rocky 

 Mountain area are simulated by means of a fundamental model. Model algorithms 

 representing hydrologic processes are sensitive to vegetational changes within the 

 subalpine vegetation zone. Reductions in water yield are predicted as the vegeta- 

 tion on a small Utah watershed proceeds from a grass-forb type to aspen to 

 conifers. Streamflow changes are largely attributable to an interaction between 

 seasonal consumption for each vegetation type and the influence of vegetation 

 type on snowpack. The model synthesizes present understanding and provides 

 a framework for future watershed research. 



