Mohammad Ali Zare Chahouki; Masoud Yousefi; Mohammad Jafari; Hossein Azarnivand; Marjan Shafizadeh Nasrabadi
Abstract
The current research was carried out to find out the most effective environmental factors in plant species occurrence by classification and ordination methods. For this purpose, the study was conducted in Nir rangelands of Yazd province and topography, climate, soil and grazing intensity data of the ...
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The current research was carried out to find out the most effective environmental factors in plant species occurrence by classification and ordination methods. For this purpose, the study was conducted in Nir rangelands of Yazd province and topography, climate, soil and grazing intensity data of the region were determined. Sampling method was randomized–systematic and within each sampling unit 3-5 parallel transects with 300-500 m length, each containing 30-50 quadrates (according to vegetation variations) were established. Quadrate size was determined for each vegetation type using the minimal area; hence suitable quadrate size for different species was determined 1*2m–10*10m (2-100 m2). Soil samples were taken from 0-30 and 30-80 cm in starting and ending points of each transect. Measured soil properties included gravel, texture, available moisture, saturation moisture, organic matter, lime, gypsum, pH and electrical conductivity. To analyze environmental data, classification (using TWINSPAN) and ordination (using PCA, CCA) were used. The results indicated that soil salinity, texture and available water play the main role in distribution of plant species.
M.A Zare Chahouki; A Zare Chahouki; M Zare Ernani
Volume 63, Issue 3 , December 2010, , Pages 331-340
Abstract
The objective of this research was to study the relationships between edaphic and topographic factors with distribution of plant species. For this purpose, current study was conducted in Eshtehard rangelands of Tehran province. The sampling method was randomized–systematic and in each sampling unit, ...
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The objective of this research was to study the relationships between edaphic and topographic factors with distribution of plant species. For this purpose, current study was conducted in Eshtehard rangelands of Tehran province. The sampling method was randomized–systematic and in each sampling unit, three parallel transects with 750 m length containing 45 quadrates (according to vegetation variations) were established. Quadrate size was determined for each vegetation type using the minimal area; hence suitable quadrate size for different species was determined 1*2m (2 m2). Soil samples from the beginning and end of each transect at two depths 0-30 and 30-80 cm were taken and the measured soil properties included gravel, texture, organic matter, lime, pH and electrical conductivity. To analyze the environmental data, PCA was considered. The results indicated that gravel, texture, EC and lime play the main role in the distribution of plant species.