Vegetation condition
Vegetation condition referrs to the practical representation of the major successional stages of broad plant communities (Parker, 1954) and is mostly used to determine and assess the management practices and improvements (Bashari & Smith, 2010). Although, there are several approaches to determine vegetation condition such as the four-factor method (Parker, 1954), six-factor method (Dnubenmire, 1959), climax method (Parker, 1954), frequency method (Fox, 1984), and the Australian method (DPIF, 2004), the four-factor method is used frequently/repeatedly in Iran, to determine vegetation condition, compared to other mentioned methods. However, to overcome the problems of the four-factor method in arid and semi-arid regions, it was modified to the six-factor (Mesdaghi, 1998). In the current study, we use a modified six-factor method that is developed for arid and semi-arid regions of Western Iran by Faramarzi et al. (2010). This method is based on four factors including litter frequency (LF), percentage of weighted palatability classes (WPC), percentage of potential biomass production (ratio of actual biomass to potential biomass), and percentage of bare soil (as a measure of soil conservation) (Table 1).
Table 1. The score of different factors for range condition and classes of range condition scores (adapted from Faramarzi et al., 2010). BS: bare soil, LF: litter frequency, WPC: weighted palatability classes, BP: biomass production, RCS: rangeland condition score.