Paria Kamali; Reza Erfanzadeh; Hasan Ghelichnia
Abstract
This study aimed to investigate the effect of animal grazing on soil seed bank characteristics in the northern slopes of Alborz. For this purpose, soil seed bank characteristics were compared between grazed and ungrazed areas. Therefore, four transects perpendicular to the sides of exclosure inside and ...
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This study aimed to investigate the effect of animal grazing on soil seed bank characteristics in the northern slopes of Alborz. For this purpose, soil seed bank characteristics were compared between grazed and ungrazed areas. Therefore, four transects perpendicular to the sides of exclosure inside and outside of it were established. Then soil samples were collected within 28 plots inside and 28 plots outside of exclosure along the transects from two different depth: 0-5 and 5-10 cm. Soil samples were then spread in the greenhouse and the plant species germinated in the greenhouse were identified and removed one time per 12 days. General linear model and factorial was used to study on the effect of grazing, depth and interaction between grazing and depth on soil seed bank characteristics. In case that the interactions became significant, unpaired t-test was used to compared seed bank characteristics between grazed and ungrazed in each depth, separately. In addition, paired t-test was applied to compare seed bank characteristics between two depths in grazed and ungrazed areas, separately. The results showed that all seed bank characteristics were significantly higher in ungrazed than grazed area particularly in upper layer of soil. All seed bank characteristics were also significantly higher in upper layer than the deeper layer of soil. The results implied that soil seed bank is a reliable source to recover the over grazed degraded points in the study area.
Sayed Hamzeh Hosseini; Reza Erfanzadeh; Paria Kamali
Abstract
The study on the livestock dietary and preference value of different species are essential forrangeland management. Therefore, this study was carried out to evaluate the preference indicesof 14 plant species in Kahnuj, during two different phenological stages (vegetative growth andafter-seed-dispersal). ...
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The study on the livestock dietary and preference value of different species are essential forrangeland management. Therefore, this study was carried out to evaluate the preference indicesof 14 plant species in Kahnuj, during two different phenological stages (vegetative growth andafter-seed-dispersal). The close observation method was used to measure the preference indexfor three age classes of Rainian goat (one, three and five years). The results showed that mainand interaction effects of goat age, plant phenological stage and the kind of plant species onpreference values were significant. Older goat consumed a higher time to graze in the studyarea. Stipa capensis had the highest preference index and Rhazya stricta had the lowest. Thepreference index of most plant species was significantly variable between two phenologicalstages. In addition, in each phenological stage, the preference value of plant species wassignificantly different. In the vegetative growth stage that annual plant species were abundant,goats mostly focused on these plant species for grazing. However, in the after-seed-dispersalstage in which the annual cover decreased, goats (particularly older ones) focused on shrubs forbrowsing. As a result, Rainian goat is a grazer in the normal situation and he can be a browserin the hard condition. It was suggested that the cover of Taverniera cuneifolia to be increased inthe study area in order to compensate the deficiency of forage in long term. Artificial foragingis useful to reserve the performance of goats (particularly younger ones) in short term.