Estimation relationship between Agropyron elongatum yield and canopy cover components (case study: Chaparghoymeh rangelands of Golestan province, Iran)

Using common approaches to determine plant production rate like cutting and weighting of total vegetation biomass is too difficult and also is not cost-effective. In addition it requires much time. Most researchers studied on plants species yield estimation via plants dimensions and obtained appropriate results but they pointed out that regression equations offered for yield estimation via dimension varies in different species and environmental conditions so the best regression model must be determined for each species and environment. For this, present research was conducted to estimate yield for Agropyron elongatum in Chaparghoymeh region. Firstly, species stands were selected randomly in field, the canopy and basal area small and large diameter, plant height and canopy volume and circumference were measured. Then they harvested, dried and weighted. Results of stepwise regression indicated that just plant height was introduced in model with determination coefficient of 0.61. It was concluded that this species yield estimation via plant height is much easier and predicted results will me more precise and significant.