Investigating the Effects of Soil Factors on Biodiversity in Plant Communities of Karvan Rangeland (Case Study: Isfahan Province, Iran)
Authors
Abstract
Understanding the plant species diversity could be used as an important
indicator applied for the natural areas management. The aim of this study was to
investigate the relationships between soil characterizes with distribution and diversity of
plant in vegetation types in Karvan district (located in west of Isfahan province). For this
purpose, three vegetation types were selected as follows: Scariola orientalis-Astragalus
gossypinus (Sc.or-As.go), Hordeum fragile-Astragalus gossypinus (Ho.fr-As.go) and
Cousinia bachtiarica-Astragalus gossypinus (Cu.ba-As.go). Then, four transects random
sampling – systematic bias to the general and lateral slope of the region in each vegetation
type were placed and the name and other characterize of the plants were recorded by 90 of
randomly quadrate one m2, also the soil samples of the start and end of each transect from
two different depths (0-20 and 20-75 cm) of soil were taken. Soil samples were analyzed
and the physicochemical factors were measured. Diversity indices such as Menhinick,
Margalef and Fisher alpha were analyzed by VMSP software and soil data were analyzed
by PC-ORD software. The results of numerical indices showed a different diversity index
in vegetation types and there were significant correlation between some soil properties and
diversity index. It was concluded that the Sc.or-As.go type had the highest diversity in
comparison with the other vegetation types (Ho.fr-As.go and Cu.ba-As.go). Finally soil
properties such as organic matter, clay and soil depth had positive and the amount of lime
and gypsum had negative correlation with species diversity.
