a new approach to economic valuation of the function of forage production of rangelands (case study: summer rangelands of nour-rud watershed in mazandaran province)

forage is the main product of rangelands. so, determining its economic value as one of the main important nonmonetary functions can help managers to improve planning and optimal utilization management of rangelands. the main purpose of this study is to estimate the economic valuation of the forage of summer rangelands in nour-roud watershed basin in mazandaran province. consequently, total forage production estimated by using double method in 12 unit works. according to the heterogeneity of range forages in terms of economic and lacking organized market for transaction, have been used barely and using replacement cost method (rcm). in order to homogenize the value of all forage plants, total digestible nutrients (tdn) of each plant multiplied to its forage product to calculate the nutrition value of forage per rangeland unit work. according to the specified t.d.n of barely, the equivalent weight of barely, identified for each range/ha in different price scenarios (guaranteed, international and farm prices), total value of forage production calculated based on barely price. results showed that, forage yield equivalent to barely was estimated 276.5 kg per ha of 89826.7 usable summer rangelands. its economic value was equivalent to 713280 rials per hectare. also, its average annual economic value by 3 price senarios estimated, 64.6 milyard rials. this amount of economic value was equal to 718900 rials per hectare of nour-rud rangelands. also, the estimated forage values are only 25 percentage of total economic value of rangeland ecosystem that has been exploited as natural bequest without any investment.