فهرست مطالب

  • Volume:11 Issue:1, 2013
  • تاریخ انتشار: 1392/01/20
  • تعداد عناوین: 11
  • Oloruntade, A. J., P. A. Adeoye, P. A., F. Alao, F Pages 1-10
    Municipal Solid Waste Management (MSWM) has become the greatest problem facing many urban and semi-urban areas in Nigeria, although to varying degrees. This study suggests the various steps and approaches to combat the menace in Akure in the southwest zone of Nigeria. Such approaches include creation of special agencies for the collection, recycling and conversion of Municipal Solid Waste (MSW) to wealth. The recruitment of Sanitary Inspectors and Volunteer Youth Corps, awareness campaigns and collaboration with other government agencies have improved compliance with sanitary laws, thus helping in effective MSWM and making the city appear aesthetically pleasing and environmental friendly. There is need for MSWM cost sharing between the government and the people, strengthening of all enabling sanitary laws and adequate budgetary allocation for all concerned agencies, involvement of Private Sector Participation (PSP) and awareness campaigns to sustain the present level of MSWM efforts and increase the tempo to guard against future population increase.
  • Rahbar Hashemi M. M., Ashournia M., Rahimipour M. A., Modaberi H Pages 11-18
    Anzali International wetland is one of the most valuable water resources as registered in Ramsar convention with an extent of about 150 km2 in the south Caspian Sea. This wetland, not only has ecological and biological importance for migratory birds and rare fish species, but also is used for farms to discharge into the Caspian Sea through this wetland. Therefore its pollution control is very important for human life. In this study 6 elements (copper, iron, lead, zinc, cadmium and nickel) in Anzali wetland were analyzed by Atomic Absorption spectroscopy method.. Water samples were collected from ten sampling sites seasonally and the results were compared with each other. The detection limits obtained were 0.016 ng/ml for cadmium, 0.02 ng/ml for copper (Cu), lead (Pb) and zinc (Zn), 0.025 ng/ml for iron (Fe) and 0.026 ng/ml for nickel (Ni). Relative Standard Deviation (RSD) was 1.7%. The results showed that these heavy metals were present in the water. Concentrations of Cu (0.6 mg/l) were higher than international standards reported in some stations. This can be due to industries around the wetland. The average level of heavy metals was higher in spring than in the other seasons which can be due to increase in seasonal rainfall and intensity of flow from rivers to wetland.
  • Ehsan S., Atarodi A.R., Kianmehr M Pages 19-27
    Gradual increase of the Earth\'s surface temperature can cause many significant changes on the climate of our planet. This problem is progressively increasing. One of the main reasons for this phenomenon is the absorption of the Sun\'s energy and lack of proper reflection of emissions due to man-made activities, one of which is the increase in black surfaces. In this descriptive and cross-sectional research, black surfaces in Gonabad city and the average heat absorption in amount and the increase in average heat absorption due to these surfaces were calculated by physical formula. To date, we used the information obtained from Gonabad Isallobars Office (GIO) and other related offices in the region (from 1980-2009) and performed a simple experiment to support our claim. Many factors were found to be the cause of the increase in average surface temperature of earth, such as increase in black surfaces. These surfaces appear not only on residential buildings but also on roads which have increased (637%) during this 30-year period in Gonabad city. It was calculated that 864 m3 of the air should be replaced to cool 1 m2 of the black surfaces. The average heat of the land surface in desert cities seems to increase rapidly. Therefore, it deserves much attention on the part of local managers and city officials to design plans and make some decisions for reducing or alleviating the problem as soon as possible.
  • Imanpour Namin. J., Sharifinia. M., Bozorgi Makrani. A Pages 29-39
    Impacts of effluent from fish farming activities on fluvial ecosystems lead to deterioration of water quality and changes in the macroinvertebrates assemblage. In this study, the influence of fish farm effluents on water quality and macroinvertebrates communities of Tajan River was investigated to evaluate the suitability of macroinvertebrates based on biological metrics and indices. Benthic macroinvertebrate communities were analyzed seasonally for a period of one year. Five sampling stations were selected along the study reach of 50 km. Station 1(S1) which is located upstream from the fish farm, was used as the reference site. Station S2 and S3 were located downstream from the fish farm outlet; S4 and S5 were further downstream. In order to assess the changes in diversity and richness in relation to water quality, two major groups of sites based on similarity between macroinvertebrate communities identified by cluster analysis. Diversity of macroinvertebrates, EPT richness and EPT/CHIR indices significantly decreased toward downstream stations except for station S4. Conversely, values of HFBI and Jacard index significantly increased in the downstream stations. The present study revealed significant differences in water quality parameters between the stations located above and below the fish farms. Owing to the relatively high diversity of benthic macroinvertebrates inhabiting rivers, use of macroinvertebrate based biological indices is recommended for assessment of water quality and pollution in fluvial systems.
  • Sarhangzadeh. J., Yavari. A.R., Hemami .M.R., Jafari. H.R., Shams, Esfandabad. B Pages 41-51
    Wild goat (Capra aegagrus) is one of the most prominent mountain mammals dispersed in many habitats in Iran. However, few studies on the relationship between this species and its habitat have been conducted. This species is recognized as one of the main food source for highly endangered species such as cheetah and leopard. In this study which lasted from fall 2009 through summer 2011, seasonal habitat suitability models of wild goat in the protected area of Kouh-e-Bafgh were created. The binary logistic regression analysis comparing ecological characteristics of presence and absence points with ecological characteristics of the region have been applied. Wild goat habitat use was influenced by steep slopes, rocky substrates, and distance to water sources, vegetation, aspects and human resources (roads). Applied models could predict at least 94.7% of the model evaluation points, indicating high accuracy of the models. Suitable habitats for wild goat in protected area of Kouh-e-Bafgh were classified in different seasons based on the estimated optimal cut-off value for each model. It comprised 29.5% to 41.3% of the protected area. There was a substantial overlap between seasonal suitable habitats in different seasons, with the highest overlap between spring and summer. The overlap between suitable habitats was at least 71.6% in all seasons. The most suitable habitats of wild goat and its predator were in the core zones of the study area.
  • Sid Kalalh., Pakizevandn., Hoveidih., Taghiofm., Tavangaris., Ahmad Panahi, H Pages 53-63
    An ion imprinted polymer (IIP) based on aniline-formaldehyde was synthesized and then modified with extra aniline as cross-linker in the presence and absence of Sr (II) as the template to produce ion imprinted poly(aniline-formaldehyde) (IIPAF) and non imprinted poly(aniline-formaldehyde) (NIPAF). The sorbent was characterized by Fourier Transform Infrared Spectroscopy and was used for solid phase extraction. The kinetics of the sorption was analyzed using the pseudo-first order and pseudo-second order kinetic models. The equilibrium adsorption data of Sr (II) on synthetic polymer were analyzed by Langmuir, Freundlich, Temkin and Redlich-Peterson models. The thermodynamic parameters were determined using the equilibrium constant values obtained at different temperatures. The results showed the negative values of? G? and positive? H? which indicated that the Sr (II) adsorption process is spontaneous and endothermic. The method was applied for strontium ions determination from Tap water samples.
  • Sadeghir., Zarkamir., Sabetraftark., Van Damme, P Pages 65-76
    The genus Azolla forms a group of small-leafed, floating aquatic ferns native to the tropics, subtropics, and warm temperate regions of Africa, Asia, and America. For several decades, these ferns have been utilized for various
    e.g. as green manure, feed for animals, but also for the removal of different metals (e.g. Hg, Pb, Cr and Cd) through wastewater treatment or for elimination of nitrogenous compounds from surface water. Notwithstanding, these many advantages of Azolla, it has invaded many natural habitats, thus becoming an obnoxious weed. Azolla can grow quickly with a doubling time of only 2-5 days and form very dense mats in favourable habitats, causing many difficulties for boat transport, water animals and native plant species and becoming a source of eutrophication. The present paper gives an overview of some important ecological factors affecting Azolla?s growth over the past few decades. Moreover, for the most ecological variables discussed in this study, the authors refer to their recent publications for the habitat requirements of Azolla in Anzali wetland. Water availability is the key factor for its growth. Growth is further promoted by optimal light intensity (15-18 Klux), temperature (18?- 28?C) and relative humidity (55-83%). Wind and turbulent water can fragment and kill Azolla. The importance of both macro (e.g. phosphorus, nitrogen, potassium, calcium and magnesium) and micronutrients (e.g. molybdenum, cobalt and etc.) has also been confirmed from literature. Various types of insects (e.g. caterpillars), bacteria, fungi and viruses can affect Azolla growth. As a conclusion, understanding the habitat requirements of Azolla is very helpful for managing this aquatic fern, also for decision making in the context of wetland restoration and conservation management.
  • Bagherzadeh Lakanif., Sattarim., Sharifpouri., Kazemi, R Pages 77-84
    The influence of dissolved oxygen concentration on gill histopathology of great sturgeon (Huso huso) was evaluated in two weight classes (initial weight 280.9?49.2 g and 1217.9?138.1 g respectively). Oxygen treatments included hypoxia (2-3 mg/l), normoxia (5-6 mg/l) and hyperoxia (9-10 mg/l). The fish were acclimated to experimental tanks for one week then randomly distributed into 9 tanks in each of the initial weight classes (3 and 6 fish per tank in higher and lower initial weight classes respectively) for 8 weeks. In order to find the histopathological changes, gill samples were collected, dehydrated through ethanol series, embedded in paraffin, sectioned at 7? m thickness using a Leitz microtome and stained with H & E. No mortality was observed over the 8 weeks of the experimental period. There were significant differences in weight and feed intake between treatments in the both weight classes (P<0.05). Fork length showed significant differences in lower initial weight class (P<0.05). The main histopathological changes were observed in gills including: Hyperplasia, loss of secondary lamellae, hemorrhage and congestion in primary and secondary lamellae, lamellar fusion, epithelial lifting in secondary lamellae, clubbing of secondary lamellae, telangiectases, increase in melanin pigments and numerous vacuoles in primary and secondary lamellae (in hyperoxia treatment). All these lesions may reduce gill functional surface of gaseous exchange, impairing respiratory function.
  • Pourhashemim., Panahip., Zandebasiri, M Pages 85-95
    Acorn production plays a fundamental role in the organization and dynamics of oak forest ecosystems. Regarding acorn importance, visual survey methods have been used to estimate acorn production of oak species throughout the world. In this study, the mast indices of Brant`s oak (Quercus brantii Lindl.) were determined in a section of northern Zagros forests, almost 36 ha area, near Baneh, Kurdistan province. Different types of visual surveys (Whitehead, Christisen-Kearby, Modified Graves and Koenig) were used on 120 trees which were selected using stratified random sampling method. In early September, just prior to acorn fall, each tree was investigated using visual surveys. Furthermore, for each tree, acorn density (acorns number/m2 crown area) was calculated using crown counting to calculate the best regression model in Koenig method. Based on visual estimation indices, fair acorn production of Q. brantii was observed. There was a strong (R2 = 0.73), highly significant (P < 0.001) linear relationship between the Koenig acorn counts (X) and corresponding crown counts. Furthermore, the results of this research confirmed usefulness of the quick visual survey methods to estimate the acorn crop of Q. brantii.
  • Heydarim., Salehia., Poorbabaeih., Rostamit., Begim Faghirm., Ostad Hashmei, R Pages 97-110
    The present survey was carried out in Oak (Quercus brantii Lindl.) woodlands of Arghvan valley protected area, in Ilam province, western Iran. The main aim of this study was to survey the understory vegetation of oak in different classes of altitude (1400-1600, 1600-1800 and >1800 m) in the southern aspects, and their relationship with physical and chemical properties of soil. Four transects, with an interval of 200 m were selected from the lowest to the highest points of hillside. 25 individual oak trees were selected on and out of the transects as a plot center. The plot area was obtained using Whittaker?s nested plots and species / area curve. In order to find the relationship between soil properties and vegetation, and also to determine the most effective factors on the distribution of vegetation, multivariate procedures, i.e., Principal Component Analysis (PCA) and Canonical Correspondence Analysis (CCA) were used. Based on these analyses three groups were obtained. These groups exactly coordinated with our sample plots in altitudinal classes and had different soil and vegetation characteristics. The most important factors in the lowland group were pH, SP, OC, N,P and K, and those in the highland group were altitude, BD and stone percentage. The midland group was intermediate to these two groups, although its conditions were more similar to the highland group. The results also indicated a decrease in Shannon-Weiner and Margalef?s indices from lowland toward the highland.
  • Faghir, M. B., Shafii, S Pages 111-126
    In the present study the freshwater algae of Siahdarvishan River were sampled on a montly basis from December 2007 through November 2008. Three sampling stations (Gaght roudkhan, Shahkezr dame and Talab laleh) were chosen in the river. Some physical and chemical parameters (water temperature, total hardness, nitrate, nitrite, phosphate and pH) of water samples were measured. A total of 84 species were identified including: Chlorophyta, 36 species; Cyanophyta, 24 species; Bacillariophyta, 20 species; Rhodophyta, 2 species; Euglenophyta and Xanthophyta each with 1 species. Among the families, Oscillatoriaceae with 14 species showed the highest species richness. Taxonomic keys to genera and species are presented to facilitate the identification of algal flora of the region.