فهرست مطالب

  • Volume:10 Issue:1, 2012
  • تاریخ انتشار: 1391/05/22
  • تعداد عناوین: 15
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  • Shemshadir., Arvandm., Efendiev, A. A., Zeynalov, N. A Page 1
    In the present study seven synthetic polymers were used as adsorbents for the removal of Cd(II) from aqueous solution. The equilibrium studies were systematically carried out in a batch process, covering various process parameters that include agitation time, adsorbent dosage, and pH of the aqueous solution. The analyzing system was an atomic absorption spectrometer (Perkin-Analyst 100). It was observed in adsorption and desorption tests that synthetic polymers showed significant pH dependence, which affected the removal efficiency, robustly. Adsorption behavior was found to follow Freundlich and Longmuir isotherms. A regeneration study was also carried out.
  • Kharah., Alijanpourn., Fallah Shamsi, S. Z., Sattarim., Amirik., Rahbarm., Ahmadnezhad, M Page 9
    Kutum, Rutilus frisii kutum, is an commercially important fish in the Caspian Sea. The fish enters the rivers leading to the Caspian Sea for spawning. One of these rivers is Shiroud River. In the artificial propagation process of Kutum, different factors are involved in quality and quantity of female broods eggs and also in the best temperature and migration time for spawning. The influence of temperature and migration time on some fecundity indices and fertilization rate of female kutum in Shiroud River was studied in the spawning season. In this study, 90 individual females were studied from February to May 2007. Averages of total length, weight and age were 43.26 cm, 832.08 g, and 4.41 respectively. Results showed that maximum egg diameter (1.86 mm), number of eggs per each gram of body weight (309.12), relative fecundity (56.21) and fertilization rate (95.82 %) were obtained from 5 to 20 April (15.95?C). Maximum ovary weight (201.00 g) and absolute fecundity of eggs (49987.18) were obtained from 6 to 20 March (17.74?C). Relationship between temperature and migration time and fecundity indices was linear and weak.
  • Mousavi-Sabeth., Kamalia., Soltanim., Bania., Rostami, H Page 15
    Cobitis faridpaki Cobitis faridpaki (Mousavi-Sabet, Vasil\''eva, Vatandoust and Vasil\''ev, 2011) is found in streams of the Siahrud River in the southeastern Caspian Sea basin, and this is the first report on reproductive parameters of the newly described endemic loach. Reproductive conditions are key parameters of fish populations, and their assessment is very important for endemic fishes. To study reproduction biology of this fish, sampling was done at monthly intervals throughout the year and 258 individuals of Cobitis faridpaki, were caught from Siahrud River in the southeastern Caspian Sea basin, in the north of Iran. Age, sex ratio, fecundity, oocytes diameter and gonadosomatic index were estimated. A regression analysis was used to find relationships between fecundity and fish size (length and weight), gonad weight and age. Sex ratio differed significantly from unity and was biased to females. The mature females and males were longer than 40 and 30 mm in total length, and +2 and +1 in age, respectively. The average egg diameter was 0.578 mm. Spawning took place from beginning of May to late July when water temperature was between 19.4 to 25.1? C. Average GSI value at the beginning of the reproduction period was 9.12% and ranged between 2% to 20% in ripe mature females. The averages of absolute and relative fecundity were calculated as 1366 and 508, respectively. The absolute fecundity was significantly related to body weight and gonad weight. Based on the pattern of gonadosomatic index, it was concluded that this fish has a prolonged active reproduction period, which is a type of adaptation of short-lived small fishes to environmental conditions.
  • Moradinasab, G.H., Ghorbanir., Paighambari, S.Y., Davoodir., Daliri, M Page 25
    This study was conducted to determine length-weight and length-length relationships, relative condition factor (Krel) and Fulton?s condition factor (K) for five species including Scardinius erythrophtalmus, Carassius auratus gibelio, Cyprinus carpio, Tinca tinca and Hemiculter leucisculus belonging to Cyprinidae family. Fish sampling was carried out by gill net and fyke net in the western region of Anzali wetland (SW of the Caspian Sea) between Nov. 2010 and May 2011. 368 specimens were measured and weighed. The values of the exponent b in the length-weight relationships (LWRs) ranged from 2.5358 to 3.3613 and those of the length-length relationship (LLRs) ranged from 0.8717 to 0.9412. Also, relative condition factor (Krel) ranged from 1.00?0.11 to 1.30?0.21 and Fulton?s condition factor (K) ranged from 0.80?0.05 to 1.60?0.18 for all species.
  • Ahmadnezhadm., Sattarim., Kharah., Oryan, Sh, Hosseinzadeh Sahafi, H Page 33
    Caspian kutum, Rutilus frisii kutum, is one of the most commercially important fish species in the Caspian Sea, but there are few reports about the endocrinology of induced spawning in this fish. In the present study, 54 individuals of female broodstocks of Kutum were studied for quantity and quality of propagation index, during March and April 2007. Hormone treatments include: LHRH-A2 (1? g kg-1bw; chlorpromazine (2.5 mg kg-1bw); LHRH-A2 + chlorpromazine (1?g kg-1bw+2.5 mg kg-1bw); CPE as a positive control (1 mg kg-1bw); Physiological saline as a negative control; and normal brood stocks without injection. For histological examinations, ovarian samples of non-ovulated females were fixed in bouin\''s fluid. The routine procedures of preparation of tissues were followed and the paraffin blocks were cut at 5-7 microns, stained with H&E and studied under light microscope. The results showed that the highest percentage of ovulated females belonged to group 1 without significant difference with positive control. There was a significant difference between ovulated females in the LHRH-A2, chlorpromazine and LHRH-A2 + chlorpromazine treatments (P<0.05), while no significant differences in other propagation indices were found in any of the hormone treatments (P>0.05). Chlorpromazine could not be a potent dopamine antagonist and the microscopic observations of ovary in non- ovulated brood stocks showed that the oocytes in these treatments were in the final phase of IV stage.
  • Mahdavia., Fallah Shamsi, S. R., Nazari, R. Page 43
    Wildfire in forests and rangelands, apart from its initiating causes, is considered as an ecological disaster. Zoning natural areas according to their susceptibility to fire helps to put off operations and reduces catastrophic losses caused through a wise management plan. In this study, the zoning map of wildfire risk in forest and rangeland areas has been produced using GIS, Analytical Hierarchical Processing (AHP) and remote sensing techniques. The study area is about 196000 ha of Ilam Township, located in western Iran. The influencing factors in wildfire occurrence include current land use/cover, roads and rivers, as well as physiographic, climatic and anthropogenic themes. The locations of the wildfires have been registered by using a GPS from 2007 to 2009, to map wildfire occurring pattern in the study area. Then, using AHP techniques the influencing factors in occurrence and extension of the fires were compared in pairs and weighed. According to the weight calculated for each factor and its corresponding classes, the weighed maps of the factors were produced and employed to produce the final map of wildfire risk zoning. Finally, the zoning map of wildfire risk was produced including five classes of the risk from high to very low. Comparing the map of the wildfire risk potential to the actual fires that happened, it was found that 50 and 40 percents of the fires initiate form the areas, marked as high risk and risky zones on the map, respectively. The results indicate a high compliance of the map of wildfire risk zoning and the location of the fires in the study area. As so it predicts more than 90 percent of occurring forest and rangelands wildfires and would be helpful data for arranging a better wildfire fighting annual plan in national and regional forests and rangeland management headquarters. The model could turn to a more sophisticated one by adding extra influencing factors like, wind speed and its directions. The present model is a static one and to solve such a problem it should be promoted to a dynamic model.
  • Chauhan, S. K., Brar (Ms), Sharma, R Page 53
    The quantitative performance of wheat crop under 1-5 year old poplar plantations in irrigated agro-ecosystem was studied to ascertain the biological yield of tree and crop. Results revealed that growth and yield of wheat decreased significantly with the increase in poplar age. The per cent reduction in net grain yield was 17% under one year old poplar plantation, which increased to 52.15% under five year old plantation. The values of micro-meteorological parameters (light intensity and air temperature) were also low under plantations than in open condition and decreased with increase in plantation age. The current and mean annual increments in biomass and carbon storage curves exhibited a sharp increase of up to three years which thereafter increased with decreasing order. The carbon storage in the poplar biomass was estimated to be 34.075t/ha at the age of five years, which can be fixed as the maximum volume production rotation of this species under the prevailing conditions.
  • Sagheb-Talebi, Kh, Schtz, J. P. Page 61
    Some criteria of density in beech saplings were studied in various forest associations (mainly Galio odorati-Fagetum typicum) growing in the submontane region near Zurich (Swiss Central Plateau). The sample plots were established in regeneration gaps resulting from Swiss irregular shelter wood system (Femelschlag). Five sample plots, each 2x2m in 3 transects (a total of 15 plots in each gap, x 10 gaps), were laid out from the center to the edge of the gap and under the old growth stand in the upper, middle and lower parts of the gap. Three collective criteria (i) number of saplings (Nm-2), (ii) mean distance of saplings and (iii) crown competition factor and one individual criterion (growth space) were investigated within the sample plots. Results showed that the density of beech saplings was not homogenous. The number of saplings (Nm-2) had wide amplitude, which varied between 2.5 and 54.8 and the mean distance of saplings varied between 14.5 and 68.0 cm. The crown competition factor varied between 1 (100%) and 5 (500%) indicating five times of overlapping in crown space of saplings, while the growth space of the studied beech saplings varied between 1.2 and 12.0.
  • Bonyad, A. E.*, Simaa., Bakhshandeha., Dadras, H Page 67
    The non-destructive Meyer method was evaluated to determine the bark volume of beech (Fagus orientalis Lipsky) stands in north of Iran. The sample size was 185 standing trees collected from 4 geographical aspects (north, south, west and east) aspects. The constant k values and bark thickness (2e mm) of 185 standing trees were used to calculate the bark volume by the Meyer method. In this study, 40 trees were randomly selected from among the felled trees and analyzed for evolution of non-destructive Meyer method. As a result, 668 diameters and 1236 bark thicknesses were measured out of 40 felled trees. The bark volumes were calculated by non-destructive Meyer and sums of integration methods. The results indicated no significant differences in volume estimates based on two methods (P = 0.816, two-tailed test), There were no significant differences in Levene?s test for equality of variances between the two methods (P=0.576, two-tailed test). The bark volume variations were significantly different in the geographical aspects. Results of this study can be important for silvicultural planning and natural forest management
  • Esfahanim.*, Fardim., Asgharij., Rabieim., Samizadeh, H Page 75
    Pre-harvest desiccation of rapeseed crop may allow a more timely harvest as well as increase the speed and harvest operation efficiency as a second crop after rice. An effective desiccant which could be used as a harvest-aid with no negative effects on rapeseed yield and quality would be advantageous for oil seed crop producers and may reduce yield losses with no interferential effects on rice cultivation. Field experiment s were carried out in a split plot design at Rice Research Institute of Iran (RRII) in the 2004-2005 cropping season. Paraquat was applied to Hyola308, Hyola401, Hyola420 and RGS003 rapeseed cultivars as main plots at the rates of 0.2, 0.4, 0.8 lit. based on 20% ai.ha-1 and a non-treated plot (sub-plot) was used as a control. Paraquat treatments were applied based on grain moisture content of 40% to one third of bottom siliques of inflorescence on the main stem in late April to late May. Results showed that the effect of paraquat application was significant on grain moisture reduction rate, grain yield and oil content. Paraquat at 0.8 lit.ha-1 promoted daily grain moisture reduction (2.94% day-1) compared to the control (1.75% day-1) and harvest time (5-7 days earlier than control) with no adverse effects on grain yield and oil content. Grain yield of treated plants were the same or higher than the control. The highest grain yield was obtained with 0.4 lit.ha-1 paraquat (2370 kg.ha-1 in Hyola420 vs. the control; 2159 kg.ha-1). Results also showed that paraquat application had no adverse effect on oil content and fatty acids profile. Oileic acid content in Hyola308 at 0.2, 0.4 and 0.8 lit.ha-1 of paraquat and the control were 64.93, 64.22, 64.25 and 65%, respectively. Mean residues of paraquat in the grains for the medium to low application rates were 5.62 and 2.61 mg.kg-1, respectively and all of its rates were lower than the toxicity threshold. It can be concluded that paraquat in reduced doses, can be used as a proper desiccant in rapeseed cultivation.
  • Oladij.*, Taheri Otghsara, F Page 83
    Ecotourism as the most attractive subset of the tourism industry can contribute to natural resource conservation and local development. Although great numbers of people annually visit Abbasabad area, in Veresk, Mazandaran, to enjoy its brilliant landscape and moderate ecologic condition, there is no applicable plan for many natural attractive zones in this area. As a result, some specific well known areas are threatened by being overused while other unknown or less familiar ones remain unvisited. Therefore, proper comprehensive ecotourism plans are required to prevent overusing most widely known forests as well as new integrated plans are needed for introducing unknown potential areas to people. In this research, a feasibility study was conducted to identify potential ecotourism zones within the study area, and then applicable strategies were suggested for optimal exploitation of the area. Both Geographic Information System and Remote Sensing techniques accelerated our research process, enhanced accuracy and reduced the expenses of this study. In addition, the map of the slope, height and aspect were produced using a topographic map in an ARCVIEW environment. These three maps were overlaid to provide the Land shape map of the study area. To make an accurate decision about the most appropriate ecotourism land use, two maps of soil and vegetation cover were overlaid to produce an environmental unit map. The ecotourism potential map was obtained by measuring the available bio-environmental units on this map based on our predetermined factors in this study. The largest part of the area was identified suitable for class I alternative ecotourism. Moreover, two villages of Abbasabad and Bezmilesh made the study area appropriate for establishing an ecotourism village. According to the results of this study, Abbasabad Veresk forest area was proved to be appropriate to construct a natural forest park.
  • Mohammadi, A. A.*, Ahmadih., Taghvaye Salimie., Khalighi, Sh, Sallajegheh, A. Page 91
    With regard to the importance of instantaneous peak discharge estimation for watershed management study, and due to the lack of and unqualified climatic and hydrologic data for estimation and measurement in countries such as Iran, researchers were obliged to establish a link between constant parameters (geomorphologic) and variables (hydrologic) to present models with minimum dependence on climatic and hydrologic data in hydrologic estimations. This research has made an effort to use synthetic unit hydrographs at the drainage basin of Kan (Soleghan River) and to compare these results with recorded peak discharge at the watershed outlet, in order to derive the best model. Comparison of study models using relative mean error (RME) and root of mean square error (RMSE) in the study drainage basin located in central Alborz watershed showed that RME for the Geomorphologic model was 17.99 and RMSE was 15.49, for Snyder RME was 59.66, and RMSE was 29.83, for SCS RME was 162.63 and RMSE was 76.002 and finally triangular RME was 165.82 and RMSE was 77.44. Therefore the best estimation belonged to the Geomorphologic model followed by the Snyder, SCS and Triangular models. Owing to the lack of recorded instantaneous peak discharges in the hydrometric station of the Kan drainage basin (11 events) at Kan-Soleghan, we are not able to derive an instantaneous peak discharge model. Hence by using factors in each of the studied models, other effective factors and 283 recorded events of daily peak discharges, the daily peak discharge model can be derived.
  • Ebrahimian, M. Ainuddin Nuruddina., Mohd Soom, M. A. B., Sood, A. M. Page 103
    The major problem in the assessment of relationships between rainfall and runoff occurs when a study is carried out in ungauged watersheds in the absence of hydro-climatic data. This study aims to evaluate the applicability of Natural Resources Conservation Service-Curve Number (NRCS-CN) method together with GIS in estimating runoff depth in a mountainous watershed. The study was carried out in the semi-arid Kardeh watershed which lies between 36? 37? 17? to 36? 58? 25? N latitude and 59? 26? 3? to 59? 37? 17? E longitude, about 42 km north of Mashhad, Khorasan Razavi Province, Iran. The hydrologic soil groups, land use and slope maps were generated with GIS tools. The curve number values from NRCS Standard Tables were assigned to the intersected hydrologic soil groups and land use maps to generate CN values map. The curve number method was followed to estimate runoff depth for selected storm events in the watershed. Nash-Sutcliffe efficiency, pair-wise comparison by the t-test, Pearson correlation and percent error were used to assess the accuracy of estimated data and relationship between estimated and observed runoff depth. The results showed relatively low Nash-Sutcliffe efficiency (E =? 0.835). There was no significant difference between estimated and observed runoff depths (P > 0.05). Fair correlation was detected between estimated and observed runoff depth (r = 0.56; P < 0.01). About 9% of the estimated runoff values were within? 10% of the recorded values and 43% had error percent greater than? 50%. The results indicated that the combined GIS and CN method can be used in semi-arid mountainous watersheds with about 55% accuracy only for management and conservation purposes.
  • Noveirian, H. A., Nasrollahzadeh, A Page 115
    An experiment was conducted to evaluate the effects of biogen probiotic additives on growth performance of common carp, Cyprinus carpio. Four practical diets containing 0 (control), 0.1, 0.2 and 0.3 % Biogen probiotic were used to feed fish. Seventy-two juvenile common carp (65? 3.5g) were randomly distributed between 12 fiberglass tanks of 500 L capacity. During 60 days of feeding trial, the fish receiving probiotic feeds showed significantly higher growth performance in terms of weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), food conversion ratio (FCR) and survival rate (SR) in comparison with those fed the control diet (P<0.05). The best results in food efficiency and growth performance were observed in fish fed diets containing 0.3% of Biogen probiotic that were significantly different with that in other treatments (P < 0.05). Growth performance did not differ significantly (P>0.05) in fish fed diets containing 0.1 and 0.2 percent of probiotic. Fish carcass composition in the diets receiving probiotic improved from initial values i.e. higher levels of protein and lipid with lower levels of moisture and ash content and showed significant difference (P< 0.05) only with the basal control diet. There were no significant differences (P > 0.05) in body composition between the treatments which received probiotic. Feeding juvenile carp with diets containing Biogen probiotic improves growth performances and feeding efficiency in them; the optimum addition of probiotic is 0.3 g/100gof diet.
  • Panahia., Kohansal Vajargah, H. Page 123
    Guilan province is located in north of Iran. It plays an important natural, economic and strategic role in Iranian history due to its geographical location between the Caspian Sea and the Alborz Mountain. This particular characteristic of Guilan has made it one of the most important political centers in its history and in the history of its struggles against the central government of Iran. Iran neighborhood with Russia and Caucasia during the Safavid Dynasty has added to Guilan economic significance. Guilan silk in the Safavid era made Iran well known as far as most of traders and tourists and orientalists who traveled to Iran have pointed to it in their writings. In this study, the importance of this strategic merchandise are investigated and discussed from the viewpoint of economics, income creation, commerce, tolls, customs as well as its export, taxes, products and the commercial routes.