Sustainability of forage production of some rangeland species using univariate method in mountainous rangelands of Middle Alborz, Qazvin province

In this study, sustainability of forage production in some rangeland species of mountainous rangelands of Alamut Qazvin was investigated. These mountainous rangelands are located in the highlands of North-Eastern city of Qazvin as a part of south basin of central Alborz Mountains. The rainfall of these natural environments is 400 mm per year. Long dry season is considered as the main characteristics of the natural environments of these ecosystems. Production per hectare of 24 species was studied during four years. Combined analysis of variance for dry forage production (kg/ha) showed significant differences (p>0.01) among species and the years. According to the results of mean comparisons (Duncan’s multiple test) and cluster analysis (Ward method), Eryngium billardieri, Cousinia esfandiari, Artemisia aucheri, Verbascum speciosum, Agropyron intermedium, and Cirsium haussknechtii had higher forage production. Interaction effect of species * year was significant at 1% probability level and sustainability parameters were calculated based upon average forage production. Parameters of CVi, S2di and R2 had similar trends in introduction of sustainable species and most of them showed low forage production based upon these parameters. Parameters of Bi, W2i and S2i also showed the same trend in expression of sustainability and on the basis of these three parameters, an average forage production was recorded for most of sustainable species. In general, Cousinia esfandiari and Artemisia aucheri showed appropriate production sustainability based upon most sustainability parameters. Agropyron intermedium and Cirsium haussknechtii were not sensitive to adverse conditions while Verbascum speciosum and Eryngium billardieri were sensitive to adverse conditions. Therefore, Agropyron intermedium and Artemisia aucheri could be introduced for range improvement programs.