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Showing 6 results for Dehghan
Forough Papahn, Simin Dehghan, Mehdi Dezhman ,
Volume 5, Issue 1 (6-2013)
Abstract
Euglenoids Algae are monocellularworldwideorganismsthat are usually found in freshwater habitats. Hoor-al-Azim or Hoor-al-Hawizeh is one of the most important wildlife and aquatic ecosystem that is shared between Iran (south west) and Iraq. It is part of Mesoptamian wetland that the various changes have during the last two decades had significant effects on the both structure and function of this wetland. In this study, identification and seasonal changes of Euglenophyta in Hoor-al-Azim wetland from April 2012to March 2012 was investigated. The sample were taken monthly from four stations. Then samplesfixed by Formalin 4%. Samples were identified by invert microscope. The frequency was also calculated. In this study a total of 18species belonging to four genera, Euglena, Phacus, Trachelomonas and Lepocincliswasidentified.The genus Euglena with 9 species had the highest number of species, as well as The winter season has the highest average density (1666cells per liter) and spring with the lowest average density (333cells per liter), respectively. Among all identified species, Lepocinclistexta with a total frequency of 42% and Euglena sp with a total frequency of 9% had the highest density than other species.
Mansour Khalfehnilsaz , Mojgan Khodadadi, Simin Dehghan Madiseh, Gholamhossain Mohammadi,
Volume 5, Issue 1 (6-2013)
Abstract
Benthic algae are the most productive organisms in aquatic ecosystemms and they’re the main source of food for benthic organisms and some fish’s larvae. The aim of this study was the Identification and study of abundance of Epipleonalgaecolonies in Shadegan international wetland. Samples collected in the one year period, from April 2010 to March 2011 according to the U.S. EPA method. 18 genius of Epipleon were identified in this study. The most frequent taxa respectively were Bacillariophyceae and Cyanophyceae, because of their high tolerance to the environmental conditions. The most important genius of Bacillariophyceae were Navicula,Nitzchia and Synedra and dominant genius of Cyanophyceae was Oscillatoria that indicating their presence in the waters with medium quality. The total mean number of Epipleon was 9555/m2 in the study area. The highest frequency of Bacillariophyceae and Cyanophycea was observed in autumnandDoragh region. According to One wayANOVAanalytical method, there is no significant difference between the frequency of Epipleon genius in the different regions (P> 0.05) however a significant difference was shown in the months (P<0.05). Cluster analysis showed more than75 percent similarity for 15 genius of algea and approximately 60% similarity between Doragh and Malh. Due to high salinity, Doragh and Malh, were in one group and Rgbh and Eetaysh made another group because of their similarity for little salinity.
Maryam Mohammadiroozbahani, Nasrin Roghanizadehgan, Simin Dehghanmedise,
Volume 5, Issue 4 (2-2014)
Abstract
During 2011-2012, sampling of benthosand sediment of Dez River was done in 5 selected stationsduring two seasons of sampling,winter and summer. Samples were taken with four replicates using Peterson grab and Surber with cross-sectional area of 225 cm2. Three replications for detection and enumeration of Macrobenthos, and one replication for sediment aggregation and organic matters content were used. Physical method of burning in an electric furnace was used for measuring organic materials. To analyze sediment size, the screen series method was used. Physicochemical parameters of water were measured. During the two seasons of sampling, a total of 18 species of Macrobenthos identified which belong to 5 animal orders. Among the most common orders identified was related to the Oligochaeta with 80% abundance and then gastropods with 14.5%. At all stations except at station 4, Oligochaeta was dominant. BMWP index of water quality classified the river in two categories. Duringthe study period, stations 2 and 3 were poor and station 1 and 5 were very poor. Also based on the average score per taxon (ASPT), stations 1, 2, 3 and 5 were classified as high-probable contaminated and due to the absence of any animal species at the Station 4, this Station is introduced as Azoic.
Razieh Dehghannezhad, Rasool Zamani-Ahmadmahmoodi, Fardin Shaluei, Nasrin Gharahi,
Volume 11, Issue 3 (Autumn 2019)
Abstract
Choghakhor wetland, covering 1500 hectares, is one of the largest and most beautiful wetlands of Chaharmahal and Bakhtiari Province, Iran. To determine the trophic status of Choghakhor wetland, water sampling was performed in 40 stations during the summer season of 2017. The location of each sampling station was registered using the Global Positioning System. In this study, the eutrophication status of Choghakhor wetland was considered using a Trophic State Index (TSI) based on total phosphorus and chlorophyll a, with depth determined by Secchi disk. According to the present study’s results, the average trophic state index was calculated to be 37.35. Based on this value, the wetland is in mesotrophic status. To improve the status of Choghakhor wetland, discharge of agricultural, municipal and domestic wastewaters to the wetland should be banned.
Farideh Mahdianzadeh, Jalil Sarhangzadeh, Hojat Dehghan Dehnavi,
Volume 12, Issue 4 (Winter 2020)
Abstract
In the present study, the wintering birds of the artificial wetlands of Yazd province in 1393, 1395 and 1396 were studied. This study is one of the first studies conducted with the aim of preventing the drying process of the wetland by emphasizing on maintaining water rights and protection of migratory birds in the artificial wetland of Yazd. Data from winter and autumn counts which were carried out in 2014, 2016, and 2017, were gathered and analyzed. In this study, 48 bird species (18 species of aquatic, 18 species of waterside and 12 species waterside) were identified. The highest numbers belonged to the Fulica atra (528 individuals), Sturnus vulgaris (500 individuals) and Anas platyrhynchos (130 individuals) respectively. Among aquatic birds, the highest number of species were represented by the family of Scolopacidae (6 species). Furthermore, the family of Rallidae represented the highest number (531 individuals comprising of 3 species). The highest and lowest numbers were 2750 and 819 individuals in 2017 and 2016 respectively. The highest evenness was observed in 2016 (0.62) and the lowest in 2014 (0.39). The most diversity of Simpson and Shannon-Winer in 2016 were 4.32 and 2.01 respectively. This study has shown that the artificial wetland of Yazd, in addition to protecting and maintaining water birds, is also important for the conservation and providing habitats for terrestrial birds and thus protecting it should be of utmost importance.
Farhad Hosseini Tayefeh, Mona Izadian, Seyed Mousa Sadeghi, Masomeh Dehghani, Eyyed Qasem Ghorbanzade Zaferani,
Volume 13, Issue 3 (Autumn 2021)
Abstract
Parishan International Wetland is one of the most important freshwater wetlands in Iran, which is on the list of endangered wetlands (Montreux) due to its complete drying up and habitat changes. This research was carried out in 2018 and 2019 to investigate changes in species diversity of waterbirds and it’s relationships with water surface in PIW. Semi-winter census data were collected from the Department of Environmental, Iran. Data were analyzed using the Species Diversity and Richness (SDR-IV) software. Species diversity indices including (Shannon-Wiener and Simpson D), species richness (Margalef and Minhinick) and evenness (Pielou and Simpson E) were calculated in a period of 31 years from 1998 to 2018. Trend of changes of the wetland reservoir surface and land use have been investigated, using satellite images. Results showed that diversity indices had an increasing trend during the years 1988 to 2001 and a decreasing trend from 2001 to 2018. Diversity indices reached lowest value in 2012 with the decrease of the wetland catchment area. The average values of 5-year period of all indices from 1989 to 2008 did not differ significantly, but apart from the Minhinick index, other indices in the period of 2009-2013 and 2014-2018 had significantly lower values. (P<0.5). The wetland reservoir surface had been increasing from 1988 to 2000. From 2001 to 2018, except for the years 2005 to 2007, the trend was decreasing and from 2009, it has had almost no water areas. It was suggested that increasing the surface and depth of the wetland, diversity of incoming water resources, determining the ownership of the surrounding lands, implementation of monitoring programs, evaluation of operational plans and training of stakeholders are the most important strategies to restore biodiversity of wetland waterbirds.
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