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Study of Genetic Diversity of Sinorhizobium Bacteria Using PCR / RFLP 16S-23S rDNA Technique
E. Karimi, A. Lakzian, K. Khavazi, A. Asgharzadeh, G.h. Haghnia,
Volume 11, Issue 42 (1-2008)
Abstract

  It is important to investigate the genetic diversity and evaluate symbiotic effectiveness of the indigenous rhizobial population. It helps understand the responses of indigenous isolates to different rhizobial inoculants. In spite of the importance of bacterial diversity, there are a few scientific reports about it in Iranian soils. Genetic diversity of 150 isolates of Sinorhizobium isolated from Hamadan soils was studied by using PCR / RFLP 16S-23S rDNA technique. The results showed that all isolates clustered in three different groups. Group (I) formed 122 isolates and they were quite similar to Sinorhizobium meliloti from viewpoint of genetic characteristics. Twenty five isolates were clustered in Group (II) and they belonged to Sinorhizobium medicae. Group (III) had two isolates and they were new species and quite different from the other groups. Shannon diversity index was different within eleven different land units (Medium gradient mountains, Level lands, Plateau, Foot slopes, Depressions and Composite land) and there was a correlation between Shannon index and some soil properties. Difference in Similarity index showed that Sinorhizobium groups in each land unit were different.


Species Diversity of Bumblebees (Hymenoptera: Apidae: Bombus spp.) in Two Mountainous Regions of Central Alburs of Iran
A. Taghavi, Gh. Tahmasbi, A. A. Talebi, A. Zarnegar, A. Monfared, H. Nazarian,
Volume 12, Issue 45 (10-2008)
Abstract
The species diversity of bumblebees was investigated in two provinces, Tehran (Fasham, Zayegan) and Qazvin (Alamut, Wikan) in central Alborz during 2005-2006. Three casts of queen, worker and male bumblebees were collected during spring and summer in six dates in the two mentioned regions. Sampling of adult bees in Wikan was done from 26 July 2006 until 19 September 2006, and in Zayegan from 24 May 2006 to 17 September 2006. In sum, eleven species were collected of which eight species were common in the two regions. Data of different species casts at two regions were analyzed by Excel ver. 6 and Ecological Methodology ver. 6. 1. 2 soft wares. Species diversity of two regions was determined and compared with three indices of Simpson, Shannon-Weiner and Brillion, and evenness was calculated with indices of Simpson, Camargo and Esmit-Willson. Species richness of two regions was compared in research. The obtained results showed species diversity, evenness and species richness were more observable in Wikan compared with Zayegan. Consequently, Wikan in comparison with Zayegan was more sustainable. Similarity of two regions was 0/46, showing many differences in terms of the kinds. Also, there were 8 similar species in the two areas.
A Hybrid Fuzzy- PSO Algorithm for Catchment Regionalization in Relation to Flood Occurrence
S. Chavoshi,
Volume 22, Issue 4 (3-2019)
Abstract
Regional flood frequency studies are initialized by the delineation of the homogeneous catchments. This study was based on "Region of Influence" concept, aiming to find the similar catchments in the south of Caspian Sea. The methodology utilized the Particle Swarm Optimization Algorithm, PSO, to optimize the fuzzy system over a dataset of catchment properties. The main catchment variables in relation to flood were determined by the principle component analysis method and employed as the inputs in the fuzzy system. Catchments grouping was performed over these fuzzy input variables by the iterative process. The optimum similar groups were obtained by PSO, and the heterogeneous L-moment index was used as the termination criterion for the optimization process. A total of 61 hydrometric stations located in the study area were selected and their relevant catchments' physical, climatic and hydrologic properties in relation to flood were studied. Principle Component Analysis by Variomax Rotation Factor over the catchments datasets tended to four out of 16 physical variables, including area, mean elevation, Gravelious Factor and Form Factor, as the main parameters in terms of homogeneity with 84 percent of accumulative variance. These variables, as well as mean annual rainfall, were used as the input data to define the fuzzy system. PSO algorithm was then employed to optimize the developed fuzzy system. The developed algorithm tended to yield the best result in the 9th iteration with 26 and 22 for the minimum average and the optimum values of cost function, respectively. The topology of the resulting algorithm included inertia weight, local and acceleration rates, the number of generations and population size, with the values of 0.7298, 1.4962, 1.4962, 10 and 5, respectively. This study tended to a total of 61 regions of influence, proportional to the relevant 61 sites. According to the geographical location of the catchments in the region, it could be concluded that the geographical proximity doesn't necessarily involve homogeneity. The obtained results indicated the efficient potential of PSO-FES in the delineation of the homogenous catchments in the study area.

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