فهرست مطالب

  • Volume:9 Issue:2, 2012
  • تاریخ انتشار: 1390/11/08
  • تعداد عناوین: 16
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  • Abedir., Pourbabaei, H Page 115
    The objective of this research was to identify and describe the different Ecological Species Groups (vegetation types) present in the Rural Heritage Museum of Guilan. The study area was approximately 260 ha, which is located in the Saravan Forest Park in Guilan province, north of Iran. Sampling procedure was performed with a systematic random technique. A total of 89 plots were sampled. Classification of vegetation carried out using the Two Way Indicator Species Analysis (TWINSPAN) method showed that there were five ecological species groups in three layers; three groups in the shrub layer, nine groups in the herb layer and six ecological species groups in the regeneration layer. The results suggest improved protection and management of this area and that it can be proposed as a protected area on the basis of the numerous important species. The information obtained from the current study about this forest is useful for the design and management of this site because of its aesthetic values.
  • Hatamzadeha., Shafyii Masouleh, S. S Page 125
    The effects of cattle manure vermicompost on the growth and productivity of cymbidium (Cymbidium sp.) plants were evaluated under shade conditions. Cymbidium was grown in a container medium including 50% pumice, 30% charcoal, 10% vermiculite and 10% peat moss, which was basic plant growth medium substituted with 10%, 20%, 30% and 40% (by volume) vermicompost. The control consisted of container medium alone without vermicompost. Plants were supplied regularly with a complete mineral nutrient solution. The greatest vegetative growth resulted from substitution of container medium with 30% and 40% vermicompost, and the lowest growth was in the potting mixtures containing 0% vermicompost. Most flower buds and inflorescences occurred in the potting mixture containing 30% and 40% vermicompost, and the greatest length of inflorescences was observed in 30% vermicompost. Cymbidium grown in a container medium substituted with 30% and 40% had the most and greatest number of flowers. Some of the cymbidium growth and productivity enhancement, resulting from substitution of container medium with vermicompost, may be explained by nutritional factors; however, other factors, such as plant- growth-regulators and humates, might have also been involved since all plants were supplied regularly with all required nutrients.
  • Motesharezadehb., Savaghebi-Firoozabadi, Gh. R Page 133
    Nickel (Ni) is a heavy metal and soil pollutant but existence of small amount of it as a metallic part of urease enzyme in the plants is necessary. Remediation of spots contaminated with heavy metals is particularly challenging. Phytoremediation, the use of plants for environmental restoration, is a novel clean up technology. In this study, five levels of nickel [control (Ni0), Ni125, Ni250, Ni500 and Ni1000 (mg kg1-)] as nickel chloride (NiCl2.6H2O) and three levels of bacterial inoculants [control (B0), Bacillus safensis FO.036b (B1) and Micrococcus roseus M2 (B2)] were used in sunflower (Helianthus annus), amaranthus (Amaranthus retroflexus) and alfalfa (Medicago sativa) for phytoextraction of nickel. A factorial experiment with a randomized complete block design (RCBD) with three replications was used. Results demonstrated that by increasing the nickel concentration in soil, its absorption by the plants has increased significantly. The highest concentration of nickel was found in shoot of amaranthus (176.83 mg kg-1) and in the root of plants, in alfalfa (462.73 mg kg-1) by usage of inoculant (P<0.05). The highest absorption of nickel occurred with B1 inoculant in amaranthus, which was 459.41? gPot-1. Applying this inoculant may also cause an increase in concentration of iron and zinc in the root and shoot of the plants.
  • P. Panahi, Z. Jamzad, M. R. Pourmajidian, A. Fallah, M. Pourhashemi Page 145
    Chestnut-leaved oak (Quercus castaneifolia C. A. Mey) is one of the most important native oaks of Iran distributed in the Hyrcanian Forests. The pure and mixed stands of it cover about 6.5% of these forests. The species represents morphological variations which have resulted in the description of several infraspecific taxa by different authors. Eight taxa were recognized as subspecies and varieties of Q. castaneifolia. In this survey, a set of quantitative and qualitative micro-morphological characteristics such as type of trichome, number and length of trichome rays, type of epicuticular waxes, type and shape of stomata, shape and sculptural features of pollen exine were studied using light microscopy and scanning electron microscopy. These characters were analyzed by the discriminant analysis method and combined with the macromorphological characters to designate the variation within the species and to evaluate the existing infraspecific taxa. Based on our results, the studied taxa are defined into four infraspecific taxa as follows: Q. castaneifolia subsp. castaneifolia var. castaneifolia, Q. castaneifolia subsp. castaneifolia var. minuta, Q. castaneifolia subsp. aitchisoniana, Q. castaneifolia subsp. undulate. The studied characteristics showed to be diagnostic for identification of the infraspecific taxa.
  • Bakhshalizadehs., Bania., Abdolmalakis., Nahrevarr., Rastin, R Page 159
    The age and growth of the Persian Sturgeon, Acipenser persicus, obtained from the Iranian coastal waters of the Caspian Sea, were studied through analysis of the pectoral fin ray section from 180 specimens, ranging in fork length (FL) from 66 to 203 cm. The specimens were obtained from commercial fisheries between October 2008 and June 2010. Interpretation of growth bands in the pectoral fin ray sections was carried out objectively using the direct reading of thin sections and image analysis. The maximum age recorded in this study for the spacimens of Persian Sturgeon was 39 years. The von Bertalanffy growth parameters estimated for females were greater than for males. The estimates of asymptotic length (L?) and growth coefficient (K) of females were 173.07 cm and 0.1 year -1, respectively and for males 164.33 cm L? and 0.08 year -1 K respectively,. Total mortality coefficient (Z) for females and males was estimated to be 0.45 and 0.76 year -1, respectively. This study revealed differences in life history parameters of the Persian Sturgeon compared with those of previous studies, which may be associated with the current increased fishing pressure and degradation of environmental conditions.
  • Nemati Kutenaeem., Shahnazaria., Fazoular., Aghajanee Mazandarani, Gh., Perraton Page 169
    This study is an attempt to develop an integrated methodology to predict the impact of the Caspian Sea on flooding using Geographic Information Systems (GIS) and hydrodynamic modeling. A rise in the sea level might lead to major flooding events, and have a severe impact on the spatial development of cities and regions. The feasibility of simulating a flood event along a drain channel is evaluated near residential development areas along the Chapakroud drain. The results of the study show that about 2 km of the drain embankments would be influenced by changes in sea water levels. For elevations of -23 m and -24 m, the maximum depths of water in the drain are 3.95 m and 2.94 m. The tail of the backwater reaches 3465 m and 2390 m, respectively, leading to flooded areas of 35.97 ha and 12.88 ha. The study shows that at these elevations environmental and social problems arise with regards to the drain. The results also indicate that GIS is an effective tool for floodplain visualization and analysis. It should be noted that the mixture of salt and soft water, as a result of rising sea water level, is a problem that was not investigated in this study and should be examined in the future.
  • Mohammadi Limaeis., Naghdir., Namdaris., Bonyad, A. E Page 181
    The aim of this study was to determine the optimal cutting cycle in an uneven-aged beech forest in the North of Iran. First of all, a logistic growth model was determined for an uneven aged forest. Then, the stumpage price was predicted via an autoregressive model. The average stumpage price of beech was derived from actual timber, round wood, fire and pulpwood prices at road side minus the variable harvesting costs. Price and growth models were used in order to determine the optimal cutting cycle under different rates of interest and setup costs. The Faustmann?s model was used for optimal cutting cycle. The results indicated that the optimal cutting cycle will decrease if the rate of interest increased. The results also indicated that if the setup costs increase, the optimal cutting cycle will also increase.
  • Zarkami, R Page 189
    In the present study, classification trees (CTs-J48 algorithm) were used to study the occurrence of roach in rivers in Flanders (Belgium). The presence/absence of roach was modelled based on a set of river characteristics. The predictive performance of the CTs models was assessed based on the percentage of Correctly Classified Instances (CCI) and Cohen\'s kappa statistics. To find the best model performance, a 3-fold cross validation techniques was applied on the dataset. The effect of Pruning Confidence Factors (PCFs) was examined on the reliability and model complexity. Based on the obtained results, the induced model could predict well the presence/absence of roach in the rivers. The highest overall means of two model performances showed that the models were reliable. When analyzing the ecological relevance of CTs, it seemed that the structural-habitat variables were more the main predictors than the water quality ones to predict the occurrence of roach in rivers. In particular, the distance from the source and width contributed more to the prediction of roach while among water quality variables, only electric conductivity was relatively important in this regard.
  • Saeed Sabaee, M Page 199
    In the past 25 years, rising of the Caspian Sea level, part of a natural treat to the sea, has inundated and destroyed many buildings and arable lands and threatened many inhabitations in coastal areas. The main reason for these damages is that the law-setback has lost its efficiency and human activities have proceeded seaward. The goal of this study is to introduce a proper setback line for the southern coast of Caspian Sea on the basis of critical water elevation and the results of coastal vulnerability assessment to sea level rise. This setback contains vertical and horizontal buffers. The Coastal vulnerability index (CVI) method is used for coastal vulnerability assessment and is also used in the Geographic Information System. Five variables in two sub-indices were used in this method. The final map obtained from coastal vulnerability assessment divided the coastal zone into low, moderate, high and very high risk categories based on quartile ranges and visual inspection of data. A mean distance of very high risk category of vulnerability map from a second vertical buffer in each rural district was then proposed as a width of horizontal buffer in the same rural district.
  • Soltani, A Page 211
    Daily counts of germinated seeds of white saxaul (Haloxylon persicum) incubated at 35 different hydrothermal environments (10-25?C and 0 to -3 MPa) were carried out under controlled laboratory conditions. The seeds were then buried in sand at 4 different depths in well drained pots constantly moisturized for three weeks. In all these hydrothermal conditions, the courses of germination were completed in less than 12 days. Both temperature and water deficit conditions significantly affected the seed germination. Water potential values of -1.5 MPa reduced the germination percentage to less than one fourth of the potential viability in all ambient temperature regimes and seed germination almost completely ceased at water deficit of -3 MPa. As water potential decreased from 0 to -1.5, base temperature values slightly increased from 5.4 to 6.5? C. Six-cm depth of burial was enough to reduce germination by 50% and on an average 85% of germinated seeds at 8-cm depth failed to reach the soil surface. No seedling appeared on top of the sand bed in pots labeled \"12-cm burial depth\".
  • Salavatian, M. Page 223
    Brown trout, Salmo trutta fario, has a wide range of distribution in the north of Iran and in Karaj, Lighvanchai and Karun Rivers, but there is no report about its feeding behavior in some water resources including the Lar Natural Park. In order to study feeding behavior of this fish during spawning season, a survey was carried out in the rivers of Elarm, Aab-Sefid, Kamardasht and Delichayi in fall 2008. A total of 140 individuals of brown trout were caught by cast net and electro fishing. Mean weight and length of the samples were 130?79.5 g and 216.9?39 mm, respectively. The age of fish was 2 to 6 years and mean age was 3.02?1.3. The mean relative gut length (RLG) of samples was 0.86?1. It was found that brown trout fed on various preys (32 animal groups), that Chironomidae (88.6%), Simulidae (60%), Baetidae (51.4%) and Tipulidae (50%) have had the most frequency in the gut of brown trout. The proportion of food consumed by trout was Diptera 91.5% (Chironomidae pupa and larvae 85.8%), Coleoptera 6.4% and others 2.1%. Cannibalism was seen scarcely. In conclusion, brown trout consumes a wide range of food items in its spawning season. Therefore, it can be classified as euryphagous and carnivaorous.
  • Pourkazemim., Razikazemi, S Page 235
    In order to identify the sex marker in Mahisefied, Rutilus frisii kutum, samples from 5 male and 5 female fish were collected from the south Caspian Sea. Polymerase chain reaction random amplified polymorphic DNA (PCR-RAPD) was performed using 124 primer sets. All bands were numbered using 1 and 0 scores corresponding to the presence or absence of bands, respectively and data were analyzed using RAPDPLOT program. Results indicated that 44 sets of primers did not show any flanking site and produced no bands, while the remaining 80 produced sharp and visible bands on polyacrylamid gel. In total, 1600 bands were scored. However, none of the bands corresponded to either the male or female fish. According to the results it has been concluded that RAPD technique failed to detect sex and cannot be considered as a robust molecular tool for sex differentiation in the studied fish. The reason may be the absence of sex chromosomes in this species or that the genes corresponding to sex differentiation are spread on different autosomal chromosomes with interaction of some environmental factors.
  • Shahmohammadi-Kalalagh, Sh, Et, Al Page 243
    The feasibility of kaolinite used as a low-cost adsorbent for the removal of Pb(II), Zn(II) and Cu(II) from aqueous solutions was investigated. During the removal process, batch technique was used, and the effects of heavy metal concentration and contact time on adsorption efficiency at pH of 4.5, under a constant temperature of 20?1? C were studied. The experimental results were analyzed using four adsorption isotherm models; Freundlich, Langmuir, Temkin and Redlich-Peterson. Evaluating the correlation coefficients showed that the Redlich-Peterson isotherm described the data appropriable than others. The adsorption capacities (qm) from the Langmuir isotherm for Pb(II), Zn(II) and Cu(II) are found as 7.75 mg/g, 4.95 mg/g and 4.42 mg/g respectively. The effectiveness of kaolinite in the sorption of the three metals from aqueous system was Pb(II) > Zn(II) > Cu(II). Kinetic studies showed that a pseudo-second order model was more suitable than the pseudo first order model. It is concluded that kaolinite can be used as an effective adsorbent for removing Pb(II), Zn(II) and Cu(II) from aqueous solutions.
  • Noei, M. R Page 257
    Sturgeons are the most important fish in the Caspian Sea, but there are only a few reports on their parasite communities in the southern part of this sea. In this study, a total of 93 individuals of four sturgeon species, namely Acipenser stellatus (n= 60), A.gueldenstaedtii (n = 12), A. nudiventris (n = 9) and Huso huso (n = 12), were caught in 2 geographical regions from the southwest of the Caspian Sea (Guilan Province, Iran) from March 2010 thtough May 2011. After recording biometric characteristics, standard necropsy and parasitological methods were used to identify parasites. Standard statistical computation (mean intensity, standard deviation, range, prevalence, abundance and dominance) were carried out for the overall samples and for samples grouped by season, geographical location, sex, length and weight. The differences between groups were determined by Kruskal Wallis test and Man Whitney U test (p< 0.05). Five worm species including 2 nematodes [Cucullanus sphaerocephalus and Eustrongylides excisus (L.)], 1 cestode (Bothrimonus fallax), 1 acanthocephalans (Leptorhynchoides plagicephalus) and 1 digenean trematode (Skrjabinopsolus semiarmatus) were found in A.stellatus, A. gueldenstaedtii, A. nudiventris and H. huso.
  • Shafii, Sh, Sabetraftar, K Page 267
    The vegetation covering of a region has a direct correlation with climate. So if data is available for vegetation cover, the second variable (climate) can be easily predicted and in reverse. The dominant species in a region are indication of its climatic conditions and vice versa. Accordingly, this is of significance in the science of historical botany. Fortunately, from the first millennium AD, and during the rule of Parthian and Sassanian era, documents and archeological evidence is considerable indicating climatic and habitat conditions as well as biodiversity in the region. However, this evidence has not been used for biological sciences and ecology. Through the discovery of 2746 clay tablet writings in the ancient area of Nisa which were the actual delivery receipts of stock to a storage house, researchers are now able to study data regarding socio-economic conditions that prevailed in the Partian society and agricultural activities which took place in northern Khorasan during the first and second century BC. Moreover, Rhyton (golden and silver vessels) discovered in Sassanid era, in the first millennium AD were totally important based on animal geography. After identifying the dominant agricultural species contained on the clay tablets and the mammalian single indicator that were depicted on Rhyton, our investigation team was able to determine the appropriate climatic conditions and individual habitat circumstances for these species. Consequently, this evidence accomplished that there is no noticeable change based on the development of the dominant species of fauna and flora in the southeast of the Caspian Sea in the first millennium AD.
  • Nasrollahzadeh, A Page 279
    Guilan province is located in south and south-west of the Caspian Sea. Guilan is one of the richest and the most humid region in the country due to suitable climate, ample rainfall and many water sources (springs, rivers, creeks,..),. Despite the prevailing favorable conditions, limnological studies, especially in the mountainous regions of this province are limited. A limnological study was conducted in the Lakan area from March to June in 2008. Macrobenthos were sampled from the freshwater stream that were mostly composed of freshwater crabs. The samples were transported to the Natural History Museum in Frankfurt, Germany, and the crab species was identified as Potamon bilobatum belonging to Family Potamidae. The physico-chemical characteristics of water and the study area have been recorded.