Elaheh Fahimipour; Jamshid Ghorbani; Ghodratollah Heydari
Abstract
Soil seed bank has an important role in vegetation restoration following cessation of disturbance. In this study, the soil seed bank richness and diversity were investigated in semi-steppic rangeland with a history of land conversion into cultivation in Charmahal-Bakhtiari province. Land-use changes ...
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Soil seed bank has an important role in vegetation restoration following cessation of disturbance. In this study, the soil seed bank richness and diversity were investigated in semi-steppic rangeland with a history of land conversion into cultivation in Charmahal-Bakhtiari province. Land-use changes were identified in grassland and shrubland and then were classified into four groups according to the time since abandonment including < 5, 5-15, 15-25 and > 25 years. Aspect was considered in each group. Soil was sampled and seed bank was identified using seedling germination method in glasshouse. Then, seed bank richness and diversity indices were calculated. Results showed that in seed bank the number of perrenilas was greater than annuals. In both grassland and shrubland time since abandonment significantly influenced the soil seed bank richness and diversity. In grassland soil seed bank richness and diversity decreased with time of abandonment but in area with more than 25 yrs of abandonment seed abnk richness and diversity significantly increased. Aspect significantly affected both seed bank richness and diversity in shrubland. North slpoe showed fluctuation in seed bank richness and diversity during abandonment while an increase was found in west slope and a reduction in south and east slopes. In both sites the soil seed bank indices significantly increased shortly after abandonment (<5 yrs) but seed bank richness and diversity showed resilient in >25 yrs in grassland and >15 yrs in shrubland.
Reza Namjooyan; Jamshid Ghorbani; Ghodrat alah heydari; Ghorban Vahab Zade
Abstract
Activities related to the extraction of minerals are one of the factors causing a disturbance in rangelands. Vegetation succession in mining areas depends on the soil seed bank. For this purpose, the soil seed bank was studied in two important coal extraction sites in Mazandaran province to identify ...
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Activities related to the extraction of minerals are one of the factors causing a disturbance in rangelands. Vegetation succession in mining areas depends on the soil seed bank. For this purpose, the soil seed bank was studied in two important coal extraction sites in Mazandaran province to identify and compare seed amount between coal wastes and nearby rangeland as control. Soil and coal wastes samples were taken from 140 plots of 1 m2 in Kiasar coal mine and 115 plots in Karmozd coal mine before the growth season. Samples were kept in a glasshouse for eight months germinated seeds were counted. Results of this study showed that the germination of 28 species in Kiasar and 23 species in Karmozd. 10 and 6 species only presented in Karmozd and Kiasar coal waste, respectively. Annuals dominated the coal waste seed bank in Kiasar while perennials were common in Karmazd coal waste seed bank. In Kiasar, coal waste seed bank had less diversity and richness than that in seed bank of rangelands, but no significant differences were observed between seed bank of coal waste and seed bank of rangeland in Karmozd. Due to the harsh conditions of seed germination and seedling establishment and also low seed density in the seed bank, natural regeneration in coal wastes of these two sites will be a slow process and it needs amendment treatments and the introduction of target plants seeds.
valiollah Raufirad; Qodratollah Heidari; Hossein Azadi; Jamshid Ghorbani
Abstract
The purpose of this study was to assess socio-economic vulnerability in lowland rangelands of Aran-v-Bidgol County. Accordingly, the most important socio-economic indices were identified using literature review. The sample size was calculated based on Cochran’s formula. Data was collected using ...
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The purpose of this study was to assess socio-economic vulnerability in lowland rangelands of Aran-v-Bidgol County. Accordingly, the most important socio-economic indices were identified using literature review. The sample size was calculated based on Cochran’s formula. Data was collected using a researcher-made questionnaire. A panel of experts and Cronbach’s alpha coefficient approved respectively the content validity and reliability of the questionnaire. Me-Bar and Valdez's vulnerability formula was applied to assess the socio-economic vulnerability. Results showed that “presence of experts in rangelands”, “local problems and the collapse of past utilization systems” and “number of rangeland users” were the most important indices of social vulnerability. Findings further indicated that “life expenses of rangeland users”, “number of livestock of rangeland users”, “economic status of rangeland users”, “livestock type” and “increasing prices” are the most important indices of economic vulnerability. The results also identified that more accuracy can be obtained to assess rangelands vulnerability by integrating social and economic factors at local scale. Therefore, policy-makers and rangeland managers and practitioners should pay more attention to socioeconomic factors at local scales to sustainable rangeland management.
Fatemeh Salarian; Jamshid Ghorbani; Ghodratolah Heydari; Nosratolah Safaian
Abstract
Conservation and restoration of biodiversity is very important for degraded rangeland ecosystems. It is necessary to assess the potential of soil seed bank as a major source of species. In this study, the soil seed bank size and composition were compared between exclosure and grazed areas. This was done ...
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Conservation and restoration of biodiversity is very important for degraded rangeland ecosystems. It is necessary to assess the potential of soil seed bank as a major source of species. In this study, the soil seed bank size and composition were compared between exclosure and grazed areas. This was done in Chahar-Bagh rangelands in Golestan province. Soil was sampled in Exclosure and Grazing from 0-5 and 5-10 cm depths in 90 quadrates of 1 m2. Then seed bank composition was identified after seed germination in glasshouse. A total of 28 species from 15 families were found in soil seed bank flora of both exclosure and grazed areas. Compositae, Gramineae, and Rosaceae were dominant in soil seed bank. Also, hemicryptophyte, Forbs and perennials were abundant in the seed bank of both areas. Exclosure significantly increased the seed density of Digitaria sanguinalis, Potentilla canescens, Stellaria media, Sonchus oleraceusand Galium verum in the seed bank. The species richness and diversity indices were not significantly different between two areas. These indices significantly increased in upper soil layer in exclosure while these indices were not significantly different between two soil depths in grazed area. The result of this study showed that exclosure influenced the soil seed banks, however, there was no evidence of positive changes in species richness and diversity indices and also an increase of grasses in soil seed bank.
