The mathematical simulation of carbohydrate translocation in natural grass veld.

Abstract

The growth functions required for the simulation of production in Themeda triandra grassland were developed for the PUTU 11 growth model. The model was developed using veld production data collected during the 1980/81 growing season. The theory successfully simulated production in three subsequent years, each with widely differing climatic conditions. Carbohydrate translocation within plants, in each growth stage, is driven by the ration of the existing mass of given plant parts to the total plant mass. The mass in each plant organ strives to attain an optimal proportion of the total plant mass by means of the translocation of carbohydrate. In each growth stage a maximum translocation rate is possible into and out of each plant organ. The actual translocation rate varies sigmoidally with the relative mass ratio deviation from the desired proportion.

Keywords: afrikaans; carbohydrate; crop growth model; grassland; grassland simulation; growth; growth stage; modelling; plant parts; putu ii; south africa; themeda triandra

Journal of the Grassland Society of Southern Africa.