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.
Nima Shakeri boroujeni; Hossein Bashari; Mostafa Tarkesh esfahani
Abstract
This study sought to develop a Decision Support System (DSS) for assisting range managers todetect range condition and make informed decisions about Feridan County rangelands. All plantspecies frequencies were measured in 31 range sites with various grazing histories using step pointmethod. Four hundred ...
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This study sought to develop a Decision Support System (DSS) for assisting range managers todetect range condition and make informed decisions about Feridan County rangelands. All plantspecies frequencies were measured in 31 range sites with various grazing histories using step pointmethod. Four hundred points along four perpendiculars 30 meters transects were measured in eachsite and grazing indicator species were identified using grazing gradient analysis. The rangeconditions of the sites were determined by evaluating the frequencies of indicator species alonggrazing gradient using Resource Environment Data Information System (REDIS). The bestmanagement practices and ecological interpretation for each range condition classes were theninserted into the REDIS model. The end users can import the indicator species frequencies of aselected site into the REDIS model and obtain the required information about range condition class,ecological information and management options. According to the results, the frequencies of sixrange species in the study area can appropriately determine range condition classes quantitatively.The model performance was then evaluated by comparing the range condition classes of 12independent sites by REDIS model and ‘Four Factors’ method. The REDIS model had an accuracyof 91 percent. The mangers can save the condition position of a selected site along a conditiongradient in REDIS model; hence they could simply monitor the range condition changes of thestudied site.
