Document Type : Research Paper

Authors

1 Associate Professor, Rangeland Research Division, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran

2 Assistant Professor, Department of Range and Watershed Management, Faculty of Agriculture and Natural Resources, Urmia University, Urmia, Iran

3 M.Sc. in Rangeland Management, East Azarbaijan Organization of Agriculture – Jahad, Tabriz, Iran

Abstract

One of the objectives in rangeland management is the accurate and rapid determination of forage production to determine grazing capacity. The relationship between forage production and morphological characteristics was investigated in this study. For this purpose, two grazed and non-grazed units were selected in the mountainous rangelands of Nazlouchay, Urmia. In each of them, the morphological characteristics of A. aucheri, as the only dominant plant species that accounts for more than 50% of the plant composition, were measured within 60 one-square-meter plots located along with 100-meter transects in July 2017. After cutting off bases growth, the dry weight of the samples was determined, and its regression relationship with morphological characteristics was examined using hierarchical regression. The results showed that it was possible to estimate A.aucheri  production in the unit where the plant bases were not grazed using multiple linear regression models based on diameter, average crown size (D1), collar diameter (D2), and height (H). In the grazed units, where plant bases were grazed in the fall of last year, only the average diameter of the crown (D1) and height (H) was validated with multiple linear regression models, as the best model with RMSE equal to 3.53 and coefficient of 0.52. Due to the relatively good performance of the model and the preference for combining several morphological features in production estimation, separating models into inside and outside the exclosure can play a role in rangeland monitoring and production estimation to calculate grazing capacity and assess the intensity of rangeland utilization.

Keywords

  • Akbarlou, M., Sheidai Karkaj, E. and Mohammad Esmaeili, M., 2012. Estimation relationship between Agropyron elongatum yield and canopy cover components (Case study: Chaparghoymeh rangelands of Golestan province, Iran). International Journal of Agronomy and Plant Production, 3(5): 656-661 (In Persian).
  • Alilou, F., Keivan Behjou, F. and Moatamedi, J., 2016. Providing statistical models to estimate the production of rangeland species (Case study: Dizaj Batchi and Ghotor Ranglands of Khoy), Journal of Range and Desert Research, 22 (4): 625-638 (In Persian).
  • Arzani, H. and Abedi, M., 2015. Rangeland assessment: Vegetation measurement. University of Tehran press, Tehran (In Persian).
  • Arzani, H. and King, G.W., 1994. A double sampling method for estimating forage production from cover measurement. In proceeding of 8th biennial Australian ranglands conference, 201-202pp (In Persian).
  • Arzani, H., Dehdari, S. and King, G., 2011. Models for estimating range production by cover measurement, Journal of Range and Desert Reseach, 18 (1): 1-16 (In Persian).
  • Arzani, H., 1997. Manual of rangeland assessment plan in rangelands of Iran with various climate conditions. Research Institute of Forests and Rangelands Press, 65p (In Persian).
  • Arzani, H., 1994. Some aspects of estimating short and long term rangeland carrying capacity of Western Division of New South Wales, Ph.D. thesis, University of New South Wals, Australia.
  • Benkobi, L., Uresk, D. W., Schenbeck, G. and King, R.M., 2000. Protocol for monitoring standing crop in grasslands using visual obstruction. Journal of Range Management, 53:627-633.
  • Ebrahimi, A., Bossuyt, B. and Hoffmann, M., 2008. Effects of species aggregation, habitat and season on the accuracy of double-sampling to measure herbage mass in a lowland grassland ecosystem. Grass Forage Science, 63: 79-85.
  • Hasen-Yusuf, M., Treydte, A. C., Abule, E. and Sauerborn, J., 2013. Predicting aboveground biomass of woody encroacher species in semi-arid rangelands, Ethiopia. Journal of Arid Environments, 96: 64-72.
  • Joneidi Jafari, H., Azarnivand, H. and Zare Chahouki, M.A., 2013. Study of aboveground and below ground biomass of Artemisia sieberi shrublands with different grazing intensities in Semnan province- Iran. Pajouhesh & Sazandegi, 99: 33-41 (In Persian).
  • Motamedi, J., Arzani, H., Sheidai Karkaj, E. and Alijanpour, A., 2014. Forage quality of 25 important species from summer rangelands of Nazlo Chai Basin in Urmia. Journal of Range and Desert Reseach, 20 (4): 653-668 (In Persian).
  • Motamedi, J., Arzani, H., Jafari, M., Farhpour, M. and Zare chahouki, M.A., 2019. A model for estimating long-term grazing capacity. Journal of Range and Desert Reseach, 26(1): 241-259 (In Persian).
  • Motamedi, J., Abdul Ali Zadeh, Z. and Shidahi Karkaj, E., 2016. Field and laboratory methods in the research of grazing and animal production. Urmia University Press, Urmia (In Persian).
  • Nafus, A. M., McClaran, M. P., Archer, S. R. and Throop, H.L., 2009. Multispecies allometric models predict grass biomass in semidesert rangeland. Rangeland Ecology & Management, 62(1): 68-72.
  • Paton, D., Nun˜ez, J., Baow, D. and Munoz, A., 2002. Forage biomass of 22 shrub species from Monfrague Natural Park (SW Spain) assessed by log–log regression Models. Journal of Arid Environments, 52: 223-231.
  • Schaefli, B. and Gupta, H.V., 2007. Do Nash values have value Hydrological processes. 21: 2075-2080.
  • Tahmasebi, P., Ebrahimi, A. and Faal, M., 2012. An investigation on regression models to predict range plant production. Rangeland, 5(2):137-145 (In Persian).
  • Whelan, C., 2001. Foliage structure influences foraging of insectivorous forest birds. An experimental study. Ecology, 82: 219-231.