these models can aid the manager in understanding the explicit and implicit 

 trade-offs involved in each scenario towards judicious selection of an appropriate 

 management policy. The model or suite of models can also be used to aid in 

 identification of conflicting resource uses, thus facilitating the development 

 of a program of balanced resource use. 



While this scheme suggests modeling to be a central element in unifying 

 various aspects of resource management, there are limitations which must be 

 recognized as well. In some instances, a mathematical simulation modeling 

 approach, with attendent costs and investments of time, may not be required. 

 Simple calculations may be adequate in some instances, while scientific intuition 

 (which in itself represents a qualitative model) may be sufficient in others. 

 Great care must be taken in developing modeling programs appropriate to the 

 resource questions being addressed. For example, models are sometimes developed 

 at the wrong spatial and temporal scales, or models may be so complex that they 

 tend to obfuscate rather than clarify and objectify resource management options. 

 Nonetheless, if such potential problems are avoided, models can play a very useful 

 role in resource management, particularly if they are viewed as one of many 

 tools which can be utilized in this area of research. 



ACKNOWLEDGMENTS 



Numerous individuals have contributed directly and indirectly to the 

 research summarized here. Much of the analysis and computer programming 

 was done by S. Bollinger, while additional computation and interaction 

 was provided by T. Schueler, R. Walker, R. Thomann and K. Lezon. Assis- 

 tance in the relevant data collection and experimentation was provided by 

 S. Bunker, J. Cunningham, K. Kaumeyer, L. Lubbers, D. Marbury, M. Meteyer, 

 J. Metz, K. Staver, and R. Twilley. We are indebted to R. Costanza, T. 

 Do Ian, D. Flemer, J. Kremer, J. Smullen, S. Taylor, R. Walker, R. Wetzel, 

 M. Yaramanglou, H. Odum, J. Zucchetto, and many others for stimulating 

 interactions on the conceptual aspects of this work. This research was 

 supported by grants from the U.S. Environmental Protection Agency No. 

 R805932010 & X003248010 and from Maryland Dept. Natural Resources No. 

 C18-80-430 (82). Financial support for digital computation was provided 

 by University of Maryland Computer Science Center. Typing was done by J. 

 Gilliard and drafting by F. Younger and D. Kennedy. 



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