Experiments on a mathematical model of a pasture

✍ Scribed by G.W. Paltridge

• Publisher: Elsevier Science
• Year: 1972
• Weight: 767 KB
• Volume: 10
• Category: Article
• ISSN: 0002-1571
• DOI: 10.1016/0002-1571(72)90006-4

✦ Synopsis

The results of recent work on a mathematical model of pasture growth are reported. The model is used to show the effect of different canopy architectures on the in-canopy meteorological variables. It is used to predict the canopy architecture at various stages of growth (leaf area index) which will produce maximum growth rate and minimum evaporation. The concept of an ultimate limit to total growth rate is discussed, and it is shown by reference to the theory of the model that the amount of carbon dioxide which can be brought down into the canopy by turbulent exchange and can be consumed by the pasture appears to set a much more restrictive ultimate limit to growth rate than that set by the available radiation (i.e., ff it were possible to design a "perfect" plant whose growth rate was in no way restricted by its biochemistry). This result may have a bearing on theories of optimum stand structure. Examples are given of the predicted daily variations of Bowen ratio above a pasture, and of the effect on this ratio of soil water deficit, wind speed and canopy architecture.