عكس العمل جوامع درمنه دشتي به برخي تغييرات محيطي در استان مركزي

چكيده انگليسي :

113 Evaluating the relationships of Artemisia sieberi communities with some environmental and variables in Markazi province Atena Faraji Atena fa@gmail com November 26 2014 Department of Natural Resources Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Dr M Tarkesh M tarkesh@cc iut ac ir Supervisor Dr H Bashari Hbashari@cc iut ac ir AbstractIdentifying the effects of environmental variables and management practices on plant species distribution andthe composition of vegetation communities is important in plant ecology Exploring the relationships of plantspecies with these environmental and management variables can assist managers to identify variables respon sible for the establishment of a particular vegetation communities in an area Plant species that occur witheach other in plant communities have similar ecological requirements and make particular ecological groups This study aimed to identify the most important factors influencing Artemisia sieberi ecological group inMarkazi province Systematic random sampling method was used to measure the plant cover and density ofthe species along 100 meters transects in eleven relatively homogeneous areas Two soil samples were col lected from 0 to 30 cm of soil surface in start and end points of each established transect and their chemicaland physical properties were determined The fifteen years mean precipitation and temperature of the nearestclimatology stations were collected from the Markazi province meteorological general office The altitudeand geographic position of all sites were recorded by Geographic Position System Stocking rate grazingperiod and forage production were used to determine the grazing intensities of the sites Two Way IndicatorSpecies Analysis TWINSPAN and analysis of similarity were used to analyze the collected vegetation dataand six ecological groups including Artemisia Noaea Artemisia Scariola Artemisia Cousinia Annuals Ar temisia Astragalus Stipa Eurotia Artemisia Stipa and Salsola Artemisia Stipa were identified accordingly The species richness conditions of the sites were measured using Margalef and Manhinick indices The plantdiversities of the ecological groups were measured by Simpson Shannon Wiener and Brillouin indices ThePielou index was also used to measure evenness condition in the ecological groups Kruskal wallis test indi cated that there were significant differences between the diversity richness and evenness of the Artemisiasieberi ecological groups Shannon Wiener diversity index differed between the ecological sites considera bly hence it was identified as an appropriate diversity index The maximum and minimum plant diversitywas identified in Artemisia Astragalus Stipa and Artemisia Noaea ecological groups Principal ComponentAnalysis PCA was used to interpret the influence of environmental and management variable in the ecolog ical groups According to the results the ecological groups and soil organic matter precipitation climateindex altitude grazing intensity pH electrical conductivity and soil phosphorus percentage were significant ly correlated Results indicated that the soil organic carbon soil apparent specific weight and grazing intensi ties had the most influence on Eurotia Artemisia ecological group Precipitation climate index and altitudewere the most determinant variables in Artemisia Noeae ecological group Artemisia Astragalus Stipa andSalsola Stipa Artemisia ecological groups were mainly affected by precipitation pH and soil electrical con ductivity Artemisia Scariola ecological group was influenced by precipitation climate index pH soil appar ent specific weight and grazing intensities The altitude and soil phosphorus percentage were significantlycorrelated with Artemisia Cousinia ecological group Generalized Additive Model GAM was used to pro duce response curves of indicator species against the measured variable changes The frequency of Eurotiaceratoide Salsola spp and Noaea mucrona

فرجي، آتنا

عكس العمل جوامع درمنه دشتي به برخي تغييرات محيطي در استان مركزي

آناليز گونه هاي شاخص دوطرفه , آناليز تشابه , آناليز مولفه هاي اصلي , تنوع گونه اي , غنا , يكنواختي , مدل تجمعي تعميم يافته , منحني پاسخ گونه اي