Monthly and annual changes of forage production and consumption of Cymbopogon olivieri (Boiss) Bor., Case study: Jevengane Genou-Hormozgan Province, Iran

Abstract

Forage production in rangelands differs at different times of the grazing season and also in the same months of different years. In the present, grazing capacity is calculated for one time during the grazing season which coincides with the maximum growth of rangeland species. This causes more livestock entry in to the rangeland during the grazing season and consequently more degradation is occurred. Since it is not possible to measure the range production during the grazing season each year, therefore, it is necessary to measure it during the months of grazing season in a few years and, based on it, the long-term grazing capacity of key range species could be calculated. The aim of this study was to determine the seasonal changes of forage production and consumption of Cymbopogon olivieri during the growing season in different years. This research was performed for four years in the vegetation type of Gymnocarpos decander-Euphorbia larica, in Jevengane region of Genou, located at an altitude of 265 meters above sea level and 40 km From Bandar Abbas in south of Iran. For this purpose, the production of this species was measured in a one-hectare exclosure with one month intervals until the growth dormancy. The rest of production was measured outside the exclosure, and the amount of consumption was calculated by subtracting it from the production of inside the exclosure. The amount of forage production and consumption, after air-drying, were analyzed by SAS software. Results showed that, due to the high variability of monthly and annual rainfall in the region, forage production and consumption of Cymbopogon olivieri showed significant differences at the 1% level.