Root Distribution Models Applied to Peanuts
Greater understanding of root distribution and water uptake can lead to improved modeling of water transport processes in the soil-plant-atmosphere system. Peanuts (Arachis hypogaea L.) were grown in the field under both well-irrigated and limited-irrigated conditions. On four different sampling dates, root length density (RLD) data were obtained at eight depths and in three locations relative to the crop row. The RLD tended to be substantially greater at shallow depths in the crop row, and to be more uniform with depth for sampling locations away from the crop row. Linear and exponential models were developed for representing the spatial distribution of roots in either one or two dimensions. The exponential model better described the observed peanut root distributions. A normalized root length density was used to determine relative root distributions over four equal depth increments.