Lale Amozgar; Jamshid Ghorbani,; Maryam Shokri; Seyed Hassan Zali
Volume 12, Issue 4 , January 2015
Abstract
Environmental factors particularly soil properties influence the species composition and vegetation diversity in rangelands. Soil in some parts of lowland areain Mazandaran province is saline. This made some limitations for establishment of vegetation. In this study the relationship between vegetation ...
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Environmental factors particularly soil properties influence the species composition and vegetation diversity in rangelands. Soil in some parts of lowland areain Mazandaran province is saline. This made some limitations for establishment of vegetation. In this study the relationship between vegetation and soil properties were assessed in lowland rangeland of Hyrcanian zone in the city of Behshahr, Mazandaran Province. Vegetation was sampled along transects with 100 m length using 1 m2plots. Cluster analysis showed six vegetation types. ANOVA results indicated that greater values of species richness and diversity indices were found in Artemisia sieberi-Medicago rigidulaand Halocnemum strobilaceum-Juncus maritimus. Results from RDA analysis showed that salinity, soil texture and soil moisture are main drivers of vegetation distribution in this area. An increase in EC,CaCo3andsilt was associated with the establishment of Salicornia europaea-Spergularia marinaand Halocnemum strobilaceum-Juncus maritimus. Aeluropus littoralisand Hordeum marinum-Plantago psylliumwere found where soil had lower EC but higher moisture, Organic carbon and clay. A reduction in soil EC and soil moisture was the favorite of Artemisia sieberi-Medicagorigidulaand Juncus maritimus.
Parviz Gholami,; Jamshid Ghorbani; Maryam Shokri
Volume 9, Issue 4 , July 2012
Abstract
The conversion of natural ecosystems into artificial or man-made ecosystems due to land use change can alter both ecosystem structure and function. The soil seed bank contains a source of viable and germinable seeds which can germinate under suitable environmental conditions. This can produce a new population ...
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The conversion of natural ecosystems into artificial or man-made ecosystems due to land use change can alter both ecosystem structure and function. The soil seed bank contains a source of viable and germinable seeds which can germinate under suitable environmental conditions. This can produce a new population or renew the present plant community. Information about the soil seed bank for Iranian flora is scarce and this study aimed to study the soil seed bank in rangeland which has been excluded from livestock grazing and the nearby area with a history of rangeland conversion into arable lands. We measured the seed bank in soils taken from two depths (0-5 and 5-10 cm) and how soil seed diversity and richness changes with land use changes. The results of this study showed that land use change significantly influenced soil seed bank diversity, species richness indices and functional group. The exclosure area showed the highest species richness, diversity and functional group while these indices significantly declined as rangeland became converted into arable lands. However, the abandoned area did not show significant differences from other two sites. Moreover, some functional groups such as annuals, therophytes, Gramineae and forb significantly reduced from the exclosure to the dryland area. This may show that abandoned areas have a potential according to their diversity and richness for returning into rangelands.
