assessment and comparison of different methods for estimating forage production (case study: rangeland of kurdistan province)

today, in the rangeland management science and determination of rangecapacity, accurate and true information about range production is crucial. in fact, rangeproduction is considered as a basis for range management. the aim of this study was tocompare different methods for the estimation of forage production with four samplingmethods in the rangelands of kurdistan province, iran. the sampling methods wereadelaide technique, double sampling, estimating method, clipping and weighting method(control). a two-way analysis of variance was made to compare the methods andvegetation types. the estimating methods and plant vegetation types were considered astreatments and blocks, respectively. the results showed that adelaide method had nosignificant difference with control method and was selected as the best method forestimating the plant production in the rangelands of study area with dominant shrub plants.a significant difference was obtained between control and estimation methods. therefore,this method had lower accuracy for estimating the production of range plants. the resultsshowed that the composition of range plants was an effective factor on the accuracy ofestimating methods and also paying attention to ecosystem variability was an importantkey to achieve a suitable method in order to estimate the range production. a significantdifference was obtained between double sampling method and clipping and weightingmethod (control). it was due to various plant combinations of the study area. therefore, thedouble sampling had lower efficiency than clipping and weighting method to estimatevarious plant species such as grasses, shrub and herbaceous plants.