Scales of Interaction

Quotes from Daly and Smith, 1993
1.

2. The scale of a varying property is defined as the distance (or time) over which its quantity remains the same before significantly changing. The physical processes most likely to influence biological activity in the ocean are those that occur in the space/time domain intrinsic to specific organisms.
For example, the doubling time of phytoplankton ranges from about 0.5 to 10 days, in which time an individual cell may be transported several kilometers by currents. Thus, small- to meso-scale physical processes are relevant to the study of phytoplankton.

3. This review indicates that biological processes may be more important at smaller scales where behavior such as vertical migration and predation may control the location and production of plankton. Physical processes may be more important at larger scales in structuring biological communities and determining particle flow, but the magnitude of biological distributions also is determined by biological interactions.

4. Non-linearities in biological dynamics over different scales often confound interpretation of patterns. Thus, understanding and prediction of ecosystem function must derive from the study of fundamental processes in conjunction with the coupling of circulation and biological models.

5. The variability of physical forcing, particularly unpredictable fluctuations, may be more important to understanding biological activity than the mean conditions. Spectral analysis provides information on the scales of variability and is useful for comparing the effects of external forcing on different ecosystems.