Mahboubeh Hadinejad; Reza Erfanzadeh; Hasan Qelichnia
Volume 27, Issue 4 , December 2020, , Pages 742-751
Abstract
The persent study was designed to investigate the effect of canopy cover of three woody species, Amygdalus scoparia, Daphne mezereum, Ebenus stellata on the composition and density of soil seed bank under their canopies. Fifteen individuals were selected from each of the woody species in Chenarnaz rangelands, ...
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The persent study was designed to investigate the effect of canopy cover of three woody species, Amygdalus scoparia, Daphne mezereum, Ebenus stellata on the composition and density of soil seed bank under their canopies. Fifteen individuals were selected from each of the woody species in Chenarnaz rangelands, Yazd provimce, Iran in autumn, 2018. then the soil samples were taken from under the canopies of woody species with a control treatment outside the canopy from a depth of 0-5 cm with an auger, 5 cm in diameter. The density and composition of soil seed banks in samples were measured through germination method in the greenhouse. The results of one-way ANOVA showed significant differences of total seed bank densities under A. scoparia (with average 1133.17 seed per m2), D. mezereum (with average 823.10 seed per m2), E. stellata (with average 793.21 seed per m2). In addition, total soil seed bank density was significantly higher than the outside of canpies (with average 134.48 seed per m2). Hemi-cryptophyte was the most frequent in the soil seed bank. The results of this research showed the positive effect of the canopy of woody species in increasing of density of soil seed bank in which A. scoparia showed a great impact on soil seed bank characteristics.
Nadia Kamali; ahmad sadeghipour; Alireza Eftekhari
Volume 25, Issue 3 , November 2018, , Pages 686-698
Abstract
This study was conducted to investigate the changes in the soil seed bank of Sisab region due to the pit-seeding operation. To recognize the seed bank potentials, sampling was done using a randomized-systematic method at tow depths of 0-5 and 5-10 cm in winter 2016. Two transects of 500-m length were ...
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This study was conducted to investigate the changes in the soil seed bank of Sisab region due to the pit-seeding operation. To recognize the seed bank potentials, sampling was done using a randomized-systematic method at tow depths of 0-5 and 5-10 cm in winter 2016. Two transects of 500-m length were stablished in the pit-seeding region and in the control area and 10 plots of 1m2 were used along each transect. To study the effects of pit-seeding and soil depth as well as their interaction on the soil seed bank characteristics, a factorial design was applied. In the case that the interaction between pit-seeding and depth was significant, the unpaired T-test was applied to study the seed bank characteristics in each depth of the pit-seeding and control regions. A paired T-test was also used to compare the seed bank characteristics between the two depths. The results showed that pit-seeding had significant effect on soil seed bank characteristics and caused to increased density, diversity, and species richness of seed bank. In addition, all characteristics of the soil seed bank were significantly higher in the top soil. Our results clearly showed that the pit-seeding operation not only increased the forage production in the study area but also increased the diversity and seed density, whose ultimate result could improve the rangeland ecosystem function.
Ali Asghar Naghipour borj; Jamaladdin Khaeddin; Hosein Bashari; Majid iravani; Pejman Tahmasebi
Volume 23, Issue 3 , January 2017, , Pages 442-453
Abstract
The structure and composition of plant communities are mainly affected by fire and grazing, especially in arid and semiarid rangelands. This study aimed to investigate the role of fire and grazing on soil seed bank characteristics (density, diversity and species richness) in semi-steppe rangelands of ...
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The structure and composition of plant communities are mainly affected by fire and grazing, especially in arid and semiarid rangelands. This study aimed to investigate the role of fire and grazing on soil seed bank characteristics (density, diversity and species richness) in semi-steppe rangelands of Central Zagros. A stratified random sampling was used to collect the data from 12 sites with one and five years after the last fire, and with long term light and heavy grazing history. Soil samples were collected in the autumn by auger from 0-5 and 5-10 cm from the soil surface, and the samples were cultivated in the greenhouse. All the germinated seeds were identified and counted for a 6-month period. The results showed that the one year after fire treatment under both light and heavy grazing resulted to a significant decrease in density, richness, and diversity of the soil seed bank. The richness and diversity of soil seed bank in the five-year after fire treatment and under light grazing pressure increased significantly compared to its control site. According to the results, the soil seed bank in 5 to 10 cm from the soil surface did not vary statistically under fire and grazing pressure, indicating the role of soil depth in reducing the impact of fire and grazing. Overall, it can be concluded that the grazing management after a fire event has a key role in vegetation restoration through its effects on the soil seed bank.
reza erfanzadeh; Azade Alamzadeh Gorji; seyed Hasan zali
Volume 22, Issue 4 , March 2015, , Pages 648-657
Abstract
Plant diversity and composition conservation is an important issue in ecosystem management. Therefore, management recommendations could be offered after a precise evaluation of diversity and composition. This study aimed to compare the results of two different methods namely seed germination and combined ...
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Plant diversity and composition conservation is an important issue in ecosystem management. Therefore, management recommendations could be offered after a precise evaluation of diversity and composition. This study aimed to compare the results of two different methods namely seed germination and combined method for determining the composition of soil seed bank. For this purpose, soil samples were collected from two different depths (0-5 and 5-10cm) within 28 paired plots. The seed bank characteristics were then determined through two different methods. According to the obtained results, totally 68 plant species were identified in the seed bank. In both methods, therophytes had the highest relative abundance. However, geophytes and hemi-cryptophytes were significantly higher in germination method as compared with combined method. The similarity between above-ground vegetation and soil seed bank was totally low and it was higher in germination method as compared with combined method. Since plant composition plays a key role in ecosystem function, in this research it was tried to demonstrate the composition of soil seed bank as an important part of plant composition and an important factor in recovery of vegetation.
Parya Kamali; Reza Erfanzadeh
Volume 21, Issue 4 , March 2015, , Pages 698-707
Abstract
In the present study, the effect of soil factors on above-ground vegetation and soil seed bank diversity under grazing and exclosure conditions was studied. Soil sampling was done in winter 2010 using randomized systematic method along four transects in the grazing and exclosure areas of Vaz watershed. ...
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In the present study, the effect of soil factors on above-ground vegetation and soil seed bank diversity under grazing and exclosure conditions was studied. Soil sampling was done in winter 2010 using randomized systematic method along four transects in the grazing and exclosure areas of Vaz watershed. Along each transect, 10 plots of 1m2 were established and soil samples were collected from a depth of 0-10 cm for seed bank and physico-chemical studies. Vegetation cover was measured in each plot in late spring of 2011. Soil factors such as porosity, bulk density, relative humidity, EC, pH, nitrogen, organic matter, and stone percentage were measured. Shannon and Simpson diversity indices were calculated for above-ground cover and soil seed bank and the most important factors influencing on the diversity were specified using multiple linear regression by backward elimination method. Results showed that the porosity, bulk density and organic matter had the greatest effect on the diversity of seed bank in the exclosure area. On the other hand, EC, nitrogen, organic matter, soil bulk density and porosity were the most important factors affecting the seed bank diversity of grazing area. According to the obtained results, organic matter and nitrogen were the main factors affecting the plant species diversity in the exclosure area, while in the grazing area, physical parameters such as bulk density, porosity and stone percentage had the highest impact on species diversity.
Kian Nadjafi-Tireh-Shabankareh; Adel Jalili; Nemat Alah Khorasani; Ziba Jamzad; Younes Asri
Volume 19, Issue 4 , March 2013, , Pages 601-613
Abstract
Genu protected area is located in the north–west of Bandar Abbas and its summit is 2347 meters above sea level. In this study, soil seed bank was investigated in vegetation communities. Soil seed bank plays a role in the revival of vegetation after degradation. In protected areas, understanding ...
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Genu protected area is located in the north–west of Bandar Abbas and its summit is 2347 meters above sea level. In this study, soil seed bank was investigated in vegetation communities. Soil seed bank plays a role in the revival of vegetation after degradation. In protected areas, understanding of the type of soil seed bank in terms of the production capacity of persistent and non-persistent seed bank is valuable to preserve the species especially endemic and rare species. In this study, sampling of the soil seed bank was conducted before precipitation. Sampling points were selected from 50 points in both depths of 0-5 and 5-10 cm of the soil surface to determine soil seed reserves. A total of 135 samples were selected for the study of plant sociology. Trays containing the samples were placed in a greenhouse and were irrigated regularly. In this research, the potential of soil seed reserves was investigated in terms of seed persistence in soil, and according to the results, significant differences were found in terms of seed density per meter square at different depths of soil and the life form of species in different communities. Among life forms, therophytes were more abundant in the soil seed bank while tree and shrub species were scarce. Species with persistent soil seed bank was mainly annuals. From 810 samples of soil seed bank, cultivated in the greenhouse, 3934 seeds were germinated of which 2933 and 1001 seeds were related to the depths of 0-5 and 5-10 cm of soil surface, respectively. In total, the number of seeds was related to 163 species of which 44 species had persistent seed bank. Species in the sampling units of soil seed bank with at least two seeds in the depth of 5-10 cm of the soil surface were considered as species with persistent seed bank. Other species in the region which had non-persistent seed bank were more vulnerable to degradation. In other words, if the vegetation is destroyed, they will not be able to revive.
Golnaz Rokhfirooz; Jamshid Qorbani; Maryam Shokri; Zianab Jafarian
Volume 18, Issue 2 , September 2011, , Pages 322-335
Abstract
Evaluation of changes in rangeland ecosystem after rehabilitation and restoration projects is important to determine the positive or negative effects of these projects. Parts of species composition in rangelands are in the soil seed bank as living seeds which are a potential for regeneration. Management ...
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Evaluation of changes in rangeland ecosystem after rehabilitation and restoration projects is important to determine the positive or negative effects of these projects. Parts of species composition in rangelands are in the soil seed bank as living seeds which are a potential for regeneration. Management and environmental factors may change the soil seed bank. This Study was carried out in mountain rangelands in Kabir watershed in Mazandaran province. A restoration project was done in this area 7 years ago and this study aimed to assess the effect of this project on soil seed bank. Soil was sampled random-systematically in control and restoration sites (210 samples) from 0-5 and 5-10 cm depths. Then seed bank composition was identified after seed germination in greenhouse. The results of this study showed that there were 38 species in soil seed bank whereas 71 species were existent in vegetation. Only 16 species were common between seed bank and vegetation. We found greater species diversity and richness in vegetation than that of soil seed bank. Only 18 species were common in the soil seed bank of control and restoration sites. Seventeen species were restricted to the seed bank of restored site. Among common species between soil seed bank of two sites, the project significantly influenced the seed bank of two species. Also, the restoration project significantly increased the richness and diversity of soil seed bank. Some species were unique to the specific soil depth. The results of this study showed that the soil seed bank would be altered by restoration and rehabilitation project and this depended on vegetation change due to restoration, type of treatment and time since project was performed.