Amir Mirzaie Moousavand; Ardavan Ghorbani; Mohammad Ali Zare Chahooki; Farshad Keivan B ehjoo; kiomars Sefidi
Volume 25, Issue 2 , August 2018, , Pages 235-247
Abstract
The aim of this study was to investigate the effect of environmental factors on Prangos ferulacea Lindl. and P. pabularia Lindl. distribution in the rangelands of Ardabil province. Seven habitats of Prangos genus were identified, so that P. ferulacea was distributed in three ...
Read More
The aim of this study was to investigate the effect of environmental factors on Prangos ferulacea Lindl. and P. pabularia Lindl. distribution in the rangelands of Ardabil province. Seven habitats of Prangos genus were identified, so that P. ferulacea was distributed in three habitats and P. papularia in two habitats. In each habitat, sampling sites were identified and in each site three transects of 100m were established, and the density of the study species were recorded in ten plots of 4m2. Soil samples were taken from the depth of 0 to 30 cm at the start, middle and end of each transect. In the vicinity of each habitat, sampling was done in the same way. In sampling plots, elevation, slope, aspect, and soil characteristics such as organic matter, N, P, K, pH, EC, and texture were measured. To investigate the effects of environmental factors on the presence or absence of the study species and to compare the characteristics of the variables measured one-way ANOVA and Tukey test were used.Discriminant analysis was used to determine the degree of importance of the environmental variables measured in the distribution of the study species. Results showed that P. pabularia was distributed in the habitats with the high content of P, clay, EC, rainfall, sand, slope and pH; while P. ferulacea was distributed where the elevation was high but rainfall and the content of K were low. According to the results of discriminant analysis, variables such as EC, organic matter, K, elevation, slope, aspect, silt, clay, rainfall, and temperature were effective in discrimination of sites and species distribution. The results of the present study could be useful to propose the species for range management, improvement and reclamation.
Amir Mirzaee Mousavand; Ehsan zandi esfahan; Farshad keyvan Behjoo
Volume 23, Issue 3 , January 2017, , Pages 606-617
Abstract
This research was aimed to investigate the effects of exclosure on species diversity changes under grazing and exclosure conditions in the northeast rangelands of Delfan County, Lorestan province. For this purpose, 120 quadrates of 1*1 m2 were established in a randomized-systematic method along 12 transects ...
Read More
This research was aimed to investigate the effects of exclosure on species diversity changes under grazing and exclosure conditions in the northeast rangelands of Delfan County, Lorestan province. For this purpose, 120 quadrates of 1*1 m2 were established in a randomized-systematic method along 12 transects of 100 m length at four altitude classes (three transects on each altitude class). In each quadrate, the list of species, density, the percentage of canopy cover, litter, stone and gravel, and bare soil were recorded. To evaluate the numerical indices of diversity, Ecological Methodology software (Ver., 6.2) was used and numerical indices of diversity and evenness were calculated. Data analysis was performed in SPSS software (Ver. 18). According to the obtained results, a number of 132 species were identified, belonging to 30 families and 104 genera, of which 124 and 108 species were recorded in the rangelands under exclosure and grazing conditions, respectively. Our results clearly showed higher numerical indices for richness, evenness, and species diversity under exclosure as compared with grazing condition. The canopy cover percentage of perennial grasses and forbs as well as litter percentage was higher inside the exclosure while the canopy cover percentage of annual grasses and shrubs as well as bare soil percentage was lower as compared with outside the exclosure. The density of perennial grasses and forbs increased, while the density of shrubs decreased inside the exclosure. In addition, a higher production was obtained from the rangeland under exclosure condition.