Sedigheh Zarekia; Ali Ashraf Jafari; Niloofar Zare
Volume 32, Issue 1 , May 2025, , Pages 35-49
Abstract
Background and ObjectivesThe degradation of rangelands in Iran, characterized by the decline of palatable species and proliferation of invasive plants, coupled with the abandonment of rainfed agricultural lands due to reduced productivity, has significantly compromised forage production for livestock. ...
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Background and ObjectivesThe degradation of rangelands in Iran, characterized by the decline of palatable species and proliferation of invasive plants, coupled with the abandonment of rainfed agricultural lands due to reduced productivity, has significantly compromised forage production for livestock. As various species of Astragalus serve as crucial forage resources, this study evaluated the efficacy of two establishment methods - direct seeding and transplanting - for five perennial Astragalus species (A. vegetus, A. brachyodontus, A. effusus, A. cyclophyllon, and A. brevidens) at the Homand Abasard research station.MethodologyThe experiment employed a completely randomized block design with three replications for both establishment methods. Direct seeding was conducted in November 2018 using a rainfed system with specific spatial arrangements (6m rows, 0.5m between populations, 0.75m between species, and 25cm plant spacing). Transplanting followed in April 2019 with identical spacing but received two supplemental irrigations for establishment. Data collection occurred in June-July 2021 (two years post-establishment), measuring forage production, canopy cover, plant height, and seed yield. Statistical analysis included ANOVA and Duncan's multiple range test.ResultsBoth establishment methods revealed significant interspecific differences (p<0.05) across all measured parameters. Direct seeding outperformed transplanting for all species, with A. effusus achieving superior forage yield (102 g/plant) and A. brevidens showing the highest seed production (14 g/plant) in this method. Transplanted specimens demonstrated reduced performance, with maximum forage (80 g/plant) and seed yields (11 g/plant) recorded for A. brevidens and A. effusus, respectively. Following A. brevidens, A. vegetus and A. effusus exhibited the most favorable overall performance.ConclusionDirect seeding proved more effective for Astragalus establishment under conditions of >300 mm annual rainfall with favorable distribution. However, transplanting remains viable where direct seeding is impractical due to seed shortages, poor seedbed conditions, or erratic precipitation. To ensure successful stand establishment, a two-year grazing moratorium is recommended post-planting regardless of establishment method.
Jallal Abdolahi; Hossean Arzani; Mohammad hosein Savaghebi; Mojgan Azimi; Hosein Naderi
Volume 19, Issue 1 , June 2012, , Pages 45-59
Abstract
Our country’s rangelands are mainly located in arid and semi-arid regions. Due to the low amount of precipitation and high rate of evapotranspiration, water stress is considered as the most crucial environmental stress for vegetation in this region. This study was conducted at Khud-e-sofla ...
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Our country’s rangelands are mainly located in arid and semi-arid regions. Due to the low amount of precipitation and high rate of evapotranspiration, water stress is considered as the most crucial environmental stress for vegetation in this region. This study was conducted at Khud-e-sofla rangelands for nine years (1378- 1386) to investigate the effect of precipitation fluctuation on canopy cover and production of important plant species. For this purpose, four dominant species were selected and their canopy cover and production were monitored every year in permanent and random plots, respectively. Precipitation data were collected from the nearest synoptic station. According to the data of precipitation, cumulative rain amount was calculated at various periods. The relationship between variables of plant parameters and cumulative rain amount was analyzed by step wise regression method in SPSS 13. The results showed that plant species often reacted to the precipitation fluctuations. However, various species reacted differently to the precipitation fluctuation in terms of cover and production. The total vegetation cover as well as canopy cover of Artemisia aucheri hada negative and significant correlation with winter precipitation.Whereas, precipitation of January to April and the past year precipitation exhibited a high correlation with canopy cover of Iris songarica and Stipa barbata. The forage production was also influenced by seasonal precipitation. According to the results, total yeild and the yield of Artemisia aucheri, Lactuca orientalis, Stipa barbata could be estimated by precipitation data While, estimation of forage production through the precipitation data was not enough accurate for Iris songarica.