نوع مقاله : تنوع زیستی
نویسنده
گروه آموزشی محیط زیست. دانشکده منابع طبیعی و محیط زیست. دانشگاه فردوسی مشهد
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسنده [English]
Species diversity is a part of biodiversity which refers to a lot of variety in animals and plants. The examination of species diversity in ecosystems and its changes during different years can help to understand the causes of these changes and lead to manage the problems of wildlife management. This research has identified and examined species diversity and fluctuation of bird populations using total count data in some aquatic ecosystems such as Kashafrood River, Dousti Dam, Tajan River, and Bazangan Lake (wetland) for 5 years. Conducting this study on aquatic ecosystems can be necessary in order to manage the birds and their habitats because of their outstanding values and their overexploitations by human beings. A part of this study was fulfilled based on descriptive and analytical research methods and using library references. In the other part, census data series were analyzed using ecological and statistical software such as Ecological Methodology, SPSS and Excel. Consequently, not only species diversity indices such as richness, heterogeneity, evenness, and their changes but also fluctuation of bird populations and community were calculated in the study areas. Moreover, ecosystem diversity indices (α, β, γ) were calculated and compared with each other in mentioned habitats. Furthermore, Moriseta similarity index was estimated to measure the similarity of the bird communities in the study sites. The most number of birds observed in Kashafrood River was 2667 individuals which belonged to 7 species in 2006. This number in Bazangan Lake was 2139 which belonged to 10 species in 2010. Moreover, the maximum abundance of birds in Dousti Dam and Tajan River have been seen in 2007 which was 4332 and belonged to 36 species. The results showed that the maximum species richness which was 36 observed in Dousti Dam and Tajan River and the minimum richness which was 2 belonged to Kashafrood River. According to heterogeneity and evenness indices, the trend of changes in Kashafrood River’s biodiversity was rising at first and then was falling during the mentioned time period. These two series indices experienced the increasing trends in Dousti Dam and Tajan River. Heterogeneity indices in Bazangan Lake showed upward trend at first, then decreased and again increased in the end of time period, respectively. Moreover, Evenness indices in Bazangan Lake had a downward trend. Based on Moriseta similarity index, the strongest similarity amount was 0.86 among Kashafrood River with Dousti Dam and Tajan River in 2007. The least amount of similarity was zero among Tajan River with Bazangan Lake and Kashafrood River in 2009.
کلیدواژهها [English]
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