Modeling Environmental Stress

Ulanowicz, Robert E. (1978) Modeling Environmental Stress. In: Thorp, J.H. and Gibbons, J>W> (eds.) Energy and environmental stress in aquatic systems (Conference on ..., Savannah River National Environmental Research Park, November 2-4, 1977). Springfield, VA, National Technical Information Service, pp. 1-18. (DOE Symposium Series,CONF-7)

Preview

PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader Download (255Kb) | Preview

Abstract

The word stress when applied to ecosystems is ambiguous. Stress may be low-level, with accompanying near-linear strain, or it may be of finite magnitude, with nonlinear response and possible disintegration of the system. Since there are practically no widely accepted definitions of ecosystem strain, classification of models of stressed systems is tenuous. Despite appearances, most ecosystem models seem to fall into the low-level linear response category. Although they sometimes simulate systems behavior well, they do not provide necessary and sufficient information about sudden structural changes nor structure after transition. Dynamic models of finiteamplitude response to stress are rare because of analytical difficulties. Some idea as to future transition states can be obtained by regarding the behavior of unperturbed functions under limiting strain conditions. Preliminary work shows that, since community variables do respond in a coherent manner to stress, macroscopic analyses of stressed ecosystems offer possible alternatives to compartmental models.

Actions (login required)