Gholam reza Zehtabian; Mehrnush Ghadimi; Ali Tavili; Jamal Bakhshi
Volume 17, Issue 3 , October 2010, , Pages 353-361
Abstract
This research was performed to investigate the relationship between environmental factors including water and plant composition. In other words, determining the most effective factors in distribution of vegetation types in Arak playa was the main aim of this study. To achieve this goal, the initial map ...
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This research was performed to investigate the relationship between environmental factors including water and plant composition. In other words, determining the most effective factors in distribution of vegetation types in Arak playa was the main aim of this study. To achieve this goal, the initial map of vegetation was provided and afterward water and vegetation sampling was done. Water parameters including K, Na, CL, Mg, %Na (exchangeable sodium percentage), Th, SAR, Co3, Hco3, So4, TDS (total hardness), EC, pH, and anions (sulfates, bicarbonates and chlorates) were measured. Multivariate data analysis techniques including principal component analysis (PCA) and canonical correspondence analysis (CCA) were used to analyze the collected data. The results showed that vegetation distribution pattern was mainly related to water characteristics such as Mg, TDS, Cl, anion, EC and Th. it can be concluded that according to habitat conditions, ecological needs and tolerance range of each plant species have significant relationship with water properties.
Gholam reza Zehtabian; Jamal Bakhshi; Mehrnush Ghadimi; Nader Biroudian
Volume 15, Issue 4 , January 2009, , Pages 436-446
Abstract
As the recognition impact of a plant specie plantation in a specific area can determine the effects of that plant in other parts and areas of the country, the effects of Haloxylon plantation on the stand understory in desert lands of Ardestan were studied. Three areas of Haloxylon plantation and a reference ...
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As the recognition impact of a plant specie plantation in a specific area can determine the effects of that plant in other parts and areas of the country, the effects of Haloxylon plantation on the stand understory in desert lands of Ardestan were studied. Three areas of Haloxylon plantation and a reference site which were approximately similar in terms of altitude (height), slope, soil, and geomorphology have been selected. The necessary number of plots in each area was chosen on statistical base. In this study the plant density and crown closure of the understory species in the Haloxylon stand and also, the reference area were measured. Then, by using Dankan Test and Analysis of Variance through SPSS package the achieved data of the sampling were analyzed. The study conducted that there was a significant difference between the understory coverage of plantation areas and the reference site. It is concluded that the Haloxylon plantation caused a great deal of increasing in understory species number and composition.