Sedigheh Zarekia; Niloofar Zare; Ali Ehsani; Farhang Jafari; Hasan Yeganeh
Volume 19, Issue 4 , March 2013, , Pages 614-623
Abstract
Each of the range species has certain production in different months and years of grazing seasons. Without understanding the production characteristics of species during grazing season, planning and livestock management is not feasible. Therefore, understanding the annual and monthly production of different ...
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Each of the range species has certain production in different months and years of grazing seasons. Without understanding the production characteristics of species during grazing season, planning and livestock management is not feasible. Therefore, understanding the annual and monthly production of different rangeland types is essential for efficient and effective management of livestock grazing. Consequently, relationships between forage production and climatic variables should be studied. For this purpose, annual forage production was measured in research exclosure of Khoshkerood-Saveh during 2007-2010 by clip and weigh method. Monthly rainfall in this period was calculated using Saveh synoptic station data and then the amount of cumulative rainfall in winter and spring of each year was calculated. Afterward, the relationship between production and winter and spring rainfall as well as rainfall of different months of winter and spring was studied separately. Statistical analysis was performed using Minitab software. Results showed that winter rainfall had no significant impact on the production of perennial species. However, cumulative rainfall in winter and spring showed different effects on forage production of the species. In other words, a significant relationship was observed between the production of Artemisia sieberi and Salsola laricina and rainfall while no significant relationship was recorded between the production of Stipa hohenackeriana and Poa sinaica and rainfall. Also, there was a significant relationship between cumulative rainfall in March and April and annual production of the species
Mojgan Azimi; Maryam Bakhshandeh; Abass Ali Sanadgol; Mortezah Akbarzadeh; Farhang Ghasriani; Farhang Jafari
Volume 19, Issue 2 , September 2012, , Pages 321-332
Abstract
In range management, appropriate time for utilization is set based upon plant life stages. Accordingly, phenology of Stipa hohenackeriana was studied in three research sites of Roudshor, Hasaan Abad and Khojir. This study was performed during three growth stages in 3 years. Twenty ...
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In range management, appropriate time for utilization is set based upon plant life stages. Accordingly, phenology of Stipa hohenackeriana was studied in three research sites of Roudshor, Hasaan Abad and Khojir. This study was performed during three growth stages in 3 years. Twenty species were selected and was regularly visited from mid-March 2005. Vegetative, flowering, seeding and winter dormancy were considered as phonological stages. Collected data were interpreted using climatic data (temperature and precipitation) and for each stage, growth degree days were calculated. Results showed that start and end of growth differed in different years and these changes were affected by climatic conditions especially temperature and soil moisture. St.ho had a longer growth period in cool and humid years compared to warm and dry years. But required cumulative temperatures were almost the same in different years. Results indicated that plant growth was affected by growth degree days (GDD) and cumulative rainfall during growth season. Also, the analysis of variance showed that differences in plant height at different sites and also in different years were statistically significant (P<0.05).