Hi, All DSSAT users,
  Would you like to help me for the following questions?
How is root distribution specified in DSSAT? Our objective is to define an exponentially decreasing distribution of roots (of root lenght density) as frequently used in other models. We used an exponentially decreasing SRGF in the soil file. However, the plant growth output file gives a root lenght density in the different layers (RL1D, ...) that doesn't follow the distribution that was defined according to the SRGF in the soil file. Are there some environmental modifiers (as stated in the book "Understanding options for Agricultural Production", p. 94 "The root weighing factor from the soil file is multiplied by a soil water factor to obtain the actual root depth distribution.") and how can this modifiers be disabled? Or are there also some other root parameters to be defined in relation to distribution, e.g. in the cultivar, ecotype or species file?
 
Could you provide us some paper or references where to find the details on root growth and distribution used in DSSAT/Ceres-Maize.
MUHAMMAD
DEPARTMENT OF WATER , ATMOSPHERE & ENVIRONMENT
UNIVERSITY OF NATURAL RESOURCES & APPLIED LIFE SCIENCES 
VIENNA -AUSTRIA