Search published articles


Showing 2 results for Arid

Khalil Agh1, Majid Mohammad Esmaili, Hossein Hosseinimoghaddam, Hamid Mostafalou,
Volume 4, Issue 2 (9-2017)
Abstract

The species Astragalus podolobus is one of the endemic species of winter pastures that grows in arid and semi-arid areas in the north of Gonbad-e Kavous. To investigate effective methods of breaking seed dormancy of Astr-agalus podolobus, an experiment was carried out in the framework of a completely randomized design with 15 treatm-ents and 3 replications. Treatments included controls, 98% sulfuric acid, dry chilling for 10 and 15 days, wet chilling for 10 and 15 days, and boiling water 1, 3, 5, 10 and 15 minute, respectively. Analysis of variance showed that the perc-entage and speed of germination were significant in different groups while the average time of germination in different treatments was not significant. The results of comparing mean values showed that the percentage and the speed of germination in boiling water treatments were best in comparison with other treatments with significant differences. The results of this experiment also showed that reducing the exposure time of seeds to boiling water increases the germination percentage and speed, consequently, the highest percentage and speed of germination was observed in boil-ing water 1 minute. Boiling water 1 minute treatment can increase the germination percentage up to 47% and the seed germination speed from 0.43 to 3.09 seeds per day
Sarmad Mahdi Kadhum, Hamid Ejtehadi, Farshid Memariani, Mohammad Bagher Erfanian,
Volume 7, Issue 4 (2-2021)
Abstract

Overgrazing affects plant communities, and is a significant disturbance factor in arid and semi-arid regions. The immediate changes of plant communities after overgrazing in the disturbed arid ecosystems of Iran have been poorly studied. We recorded data from 100 random samples before and after overgrazing in the Golbahar plain located in the northeastern Iran to determine the changes in the plant physiognomic, species composition, and diversity after overgrazing. We compared life-forms spectra, change in the RIVI of the recorded plant species, species composition, and species diversity before and after the grazing. Our results showed that therophytes were the dominant life-form in the area, and decreased after overgrazing. The community composition of the area remained unchanged after overgrazing. Species diversity at the level of rare and frequent species reduced after overgrazing. Our findings implied that overgrazing could not immediately affect the community structure of degraded arid areas. However, it causes changes that might reduce ecosystem services in them. It is not possible to completely exclude grazers in such areas, fencing or reducing the number of the livestock entries should be applied to restore the vegetation in the area.
 
 

Page 1 from 1     

Creative Commons Licence
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.



© 2024 CC BY-NC 4.0 | Nova Biologica Reperta

Designed & Developed by : Yektaweb