RESUMO
Eutrophication is one of the detrimental environmental problems in water reser-voirs dye to the irregular introducing nutrients [phosphorus and nitrogen]. This study aimed to explore the eutrophication state of Ekbatan Reservoir, Hamadan, western Iran. Monthly sampling was conducted during April 2010 to March 2011. Seven sampling stations were selected in the various locations of the reservoir and the samples were collected in the depth of 50 cm. The grab sampling of water for nitrogen, phosphorous and chlorophyll-a was carried out at all localities by Hatch sampler. The trophic state of the dam was determined by Carlson's Trophic State Index [TSI] and Chapra's classification. The highest concentrations of phosphorus and chlorophyll-a were measured in August and the lowest concentration for both of the parameters was determined in February. The TSI index according phosphorus concentration showed that the reservoir was in eutrophic status during May to November and was in mesotrophic status over November to May. It seems that the eutrophication process in the lake was resulted from the rural wastewaters and agricultural fertilizers. Therefore, using long term management methods includ-ing prevent of uncontrolled discharge of agricultural wastewaters is recommended in order to reduce the eutrophication in the reservoir. Decrease of phosphorus concentration in the dam by 50% can convert the eutrophic state to mesotrophic state.
RESUMO
Distribution of Tuberculosis [TB] has a special template affected by geographic and social factors. Nowadays Geographical Information System [GIS] software is one of the most important and useful epidemiologic devise for identifying geographic areas and high risk population for infection by TB. Aim of this study was assessment of Tuberculosis distribution by GIS in Khuzestan province, Iran. In this retrospective cohort study, documents of 6363 TB patients identified, in Khuzestan province at the beginning of 2005 until the end of the September of 2012 were assessed and sampling method was census. The data was gathered by TB-Register Center. TB incidence was evaluated by GIS maps according to climatic and vegetation with 1:25, 000 scale. The data was analyzed in SPSS software and means plot and Independent's t-test, ANOVA with a significance level of less than 5% and Eta Correlation. Spread of Tuberculosis in climatic and vegetation were plotted in GIS maps, accumulative incidence rate was calculated separately for each area. There was a statistical significant relationship between cumulative incidence rate of disease and climatic [P=0.017] and the Eta correlation coefficient was 0.379 [P=0.011]. There was a statistical significant relationship between cumulative incidence rate of TB and vegetation [P=0.004] and the Eta correlation coefficient was 0.388 [P=0.188]. Mean age and median age of patients were 39.3 +/- 18 and 35+6.5 years respectively. For women, mean age was 2.1 years older than men and this difference was statistically significant. [P=0.0001]. The risk of TB infection is closely associated with the climatic and vegetation. So the risk of TB in extra-dry climate and vegetation of highland meadows is more than other areas. Special care and services to high-risk areas is recommended