© 1990 Heron Publishing—Victoria, Canada
ECOPHYS: An ecophysiological growth process model for juvenile poplar
H. M. Rauscher (1), J. G. Isebrands (2), G. E. Host (3), R. E. Dickson (2), D. I. Dickmann (4), T. R. Crow (2) and D. A. Michael (5)
1. USDA Forest Service, North Central Forest Experiment Station, Grand Rapids, MN 55744, USA / 2. USDA Forest Service, North Central Forest Experiment Station, Rhinelander, WI 54501, USA / 3. Natural Resources Research Institute, University of Minnesota, Duluth, MN 55811, USA / 4. Department of Forestry, Michigan State University, East Lansing, MI 48824, USA / 5. Software Innovations, Battle Creek, MI 49017, USA /
Summary
The ECOPHYS model is an ecophysiological growth process model of juvenile poplar clones growing under near optimal conditions.
The theoretical basis for the ECOPHYS model is that (1) individual leaves drive and control growth; (2) the microenvironment
at the leaf exerts primary control of photosynthetic rates; (3) leaf orientation is a major determinant of that microenvironment,
(4) photosynthates produced by leaves are allocated among meristematic and respiratory sinks: and (5) the plant’s genome and
microenvironment regulate photosynthate allocation. The major driving variables are solar radiation, temperature, and clonal
morphological and physiological factors. The user can interact or override any or all of the input variables to examine the
effects of such changes on photosynthetic production and growth. Verification and sensitivity analyses of ECOPHYS are presented
and discussed. The use of ECOPHYS as a research tool is illustrated with several examples. Model potential and limitations
are discussed.
