فهرست مطالب

نشریه علوم و فنون منابع طبیعی
سال سوم شماره 2 (تابستان 1387)

  • تاریخ انتشار: 1387/06/30
  • تعداد عناوین: 8
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  • A. Mogemi *, M. Molayi, A.R. Ganji, M. Shaygan, M. Mogemi Page 1
    The Salmanshahr area is one of the areas (zones) that is important from the geomorphologic and Karstic water resource's point of view. The studies conducted on the heights of this area indicate that these heights contain high amount of undifferentiated cretaceous limestones, which extend towards the east. The movement of the major fault in the northern Alborz has caused the shemshak formation in the area to be in fault border and in contact with cretaceous limestones (the 100000/1 geological plan of chalous). The unpermeability of the coal bearing formation of shemshak and the drainage of surface waters from these heights toward the plains can be one of the reasons for the formation of these kinds of karsts in the area. By analyzing the data obtained from the chemical analysis of water samples and drawing piezometric maps using the monthly statistics received from the piezometers of the plain, the influence of karstic areas on the ground waters of the plain was proved, and a karstic polya named Danial was also distinguished from the other areas (Matrices 4, 5, and 6 and Satellite Pictures).
    Keywords: Geomorohology, Karst, Piezometer, Polya, Chemical Analysis, Water Budget, Unit Hydrographs
  • M.R. Tatian *, R. Tamartash, M. Shaabani, M. Ehsani Page 17
    The recognition of relationship between vegetation and physiographic factors can be useful and effective in estimating the kind and amount of vegetation for the management of various ecological ecosystems of rangelands. For this purpose, the present research deals with studying the effects of physiographic factors on the various vegetative changes of Lasem watershed rangelands. The samples were randomly selected from the vegetatives after the identification of plant types and the determination of the size and number of them. Then, the databases, including the slope, aspect, altitude, and lithology in the area of Arc GIS 9.2 were prepared, and by overlaying them, and after the field controlling, the needed data in each plant type were determined. Finally, the correlation between the physiographic factors with plant types and the means of the properties of the groups were computed with the SNK test. Also, the plant communities were ranked and classified with DCA, CCA and Canoco software, The results showed that shrubs had more correlation with altitude and aspect than grasses, but none of them had any significant relation with the slope. Also, the overgrazing of livestocks decreased the amount of this correlation.
    Keywords: Vegetation, Slope, Aspect, Altitude, Lasem
  • H. Kiadaliri, M. Moarefi, A. Kialashaki *, Y. Ahangaran Page 33
    Due to the importance of the beech trees which are one of the most valuable species of tree in the north forests of Iran, the mass growth of the Cryptoco ccus fagi, which can be the vector of Nectria SP., and cause the beech bark disease, brought about some worries. So in order to prevent the probability of any danger, the condition and biology of the above-mentioned pest, Nectria SP., and the parasitic fungi was studied. After identifying the areas with high infection to the pest and the probable existence of the disease, the sample pests were collected. This Cryptococcus fagi can be the carrier of the Nectria SP. fungi, the cause of the bark disease on the beech trees the symptoms of which exist in some areas in the north of Iran at the present time. There are some black spots as big as a 10-rial coin under the tree bark which seem reddish orange. There are also reddish-brown oozes or some black oozes from the decayed parts of the tree. These are often the first symptoms of the trees attacked by the Nectria Sp. The inner and outer parts of the bark die due to the growth (invasion) of the fungi. The tree’s textures often produce callose as a result of the growth of this fungus, and the bark becomes thick and rough, which then creates small cancerlike injuries like the mouth of a volcano. The reddish protis with spores inside which are certainly the symptoms of the disease appear on these trees. Finally, the tree trunk will be surrounded by these dead textures and will die as its dead textures increase. The beech trees dying and drying due to the Nectria Sp.can be seen from a far distance.
    Keywords: Beech Trees, White Beech Scale, Beech Bark Disease, Forests of the North of Iran
  • B. Kord *, A. Kialashaki, B. Kord, S. Pourabbasi Page 45
    This study was warried out to investigate the response of quantitative characteristics of Pinus Eldarica Medw trees to slope and geographical variations in Chitgar Forest Park. For this aim, 70 samples of circular plot forms of 2R were selected from four main geographical aspects and three slope levels of 0-15, 16-30, and 31-45 percent. In each sample, the diameter at breast height and height of trees were measured. The results showed that slope and aspect had effects on the diameter at breast height and height of pine Eldarica Medw of Tehran whereas the interaction between slope and aspect was significant on the height of trees. Also, the thickest and highest pine Eldarica Medw trees are located in the eastern and southern aspects and in the 0-15 percent slope. In order to increase the size of quantitative features, the plantation of this species in similar ecological regions in the eastern and southern aspects and in relatively mild slopes is recommended.
    Keywords: Afforestation, Slope, Gographical Aspect, Diameter at Breast Height, Height, Chitgar Forest Park
  • A. Najafi *, S. Kazemi Najafi Page 53
    In this study the short – term flexural creep-recovery of rice hull flour / HDPE (high density polyethylene) composites were investigated. The rice hull flour / HDPE composites were manufactured by using a dry blend/ hot press method. In this method the powder of HDPE (virgin, recycled and mixed of them) and dried flour of rice Hull were mixed in proportion to 60% of the loading weight in an experimental mixer with 1500 rounds per minute in five minutes. Speciment panels with the sizes of 35×35×1 cm were manufactured from the obtained mixtures by using the hot pressure at 190 oc. The nominal density of panels was 1 gr/cm3. In order to study the short-term flexural creep – recovery behaviour of composites, the flexural speciments were pressed at 10, 20 and 30 percent of maximum bending load and held constant during the test. The displacements in midpoint of speciments were measured with an extensometer during creep-recovery time. The total times were 60 minutes (30 minutes for creep and 30 for recovery). The results indicated that the creep – recovery behaviour of the composites was affected by the type of HDPE, and load levels. The behaviour of composites was obviously non-linear at higher levels of load. The most permanent recovery in the composites of rice hull flour/ HDPE was observed in the high levels of load. The results also revealed that the creep behaviour in rice hull flour/HDPE followed the Findley power law.
    Keywords: Creep-Recovery Behaviour, Rice Hull Flour, Recycled High Density Polyethylene, Findley Power Law
  • E. Mataji * Page 65
    The Histosol soils have been one of the tweleve main categories of soil according to the U.S.A (N.R.C.S.U.S.D.A) soil taxonomy used much in agriculture and gardening due to their specific physical and chemical features. These soils have the concentration and dispersion in the east of Nowshahr, ranging from the Mazgah areas to Aliabad Asgarkhan. The composed model of these soils often followed the low coastal lands model. The strong tectonic of this area, the advances of the sea, and the construction of coastal dam, the concentrated plant coverage and the high stability have been the main conditions for the formation of these soils in the area. The Histosol soils of the area with an average thickness of about 2 meters have a volume of about 20 millions m3, and 6% of the total coastal areas of Nowshahr and Chalous consist of these soils. The component parts of these soils in the area mainly result from the analysis of the remainders of Alnus Glutinosa, Canes and Cartex. The Histosol soils of the area are the Hemist suborder in categorization.
    Keywords: Histosol, Lagoon Basin, Low Land Model, Quaternary of Khazar Basin
  • R. Aliashrafipur, E. Adeli, S. Bbai Kafaki, M. Namiraniyan Page 77
    Obtaining the sustainable development has several preconditions of which the most important one is determining territories’ use based on the land use programming. Therefore, the present study was conducted in an area of 7181 hectares in the aquiferous basin of Dohezar, Tonekabon, with the capability of tourism use for both the concentrated and unconcentrated, and by using the multi-criterion assessment model. In the method of multi- criterion assessment, all indexes measured in the linear model were taken into consideration. After the formation of decision- making matrix and the giving-weight process, in addition to determining the best choice with circumferential life units, for each kind of recreation, the determined ranks of choices were classified, then circumferential life units were classified based on the rank they had received for the tourism talent. Finally, the talent map of this area for the use of recreation was prepared in both concentrated and unconcentrated forms, The results showed that the concentrated circumferential life method No.2 in an area of about 6.907 hectares is considered to be as the best choice for the concentrated recreation, and circumferential life unit No.1 in an area of about 302.411 hectares is considered to be as the best choice for unconcentrated one. At the end, the area classification map of tourism use was provided separately in detail for both the concentrated and unconcentrated tourisms.
    Keywords: Land Use, Aquiferous Basin, Eco-Tourism, Dohezar of Tonekabon, Multiple Criteria Decision Making, Outdoor Recreation, Environmental Unit
  • D. Sikarudi Fazeli, S.M. Hosseini, H.R. Moradi Page 89
    Due to the economic and currency importance of king prawn in the fresh water, an investigation was carried out in Anzali wetland to study the potential Habitat for the natural growth of Astacus Leptodactylus. The samples were selected from 13 station from inflow rivers (Behamberoud, Morghak, and Khalkayi, Spand, Koulehsar, Chomestghal, Nargestan, Siadarvishan, Hendekhaleh, Pirbazar, Bigroud, Ghanadi, Ramezan Bekandeh, Sheyjan). The superficial water samples were prepared by Nansen bottle, and were prepared according to the APHA standard method to determine their physiochemical parameters. To determine the parameters of BOD, Calcium, total Phosphor, total hardness and NH4, the Standard Method for Water and waste Analysis was used. The results showed that the average temperature ranged from 18.39 to 19.25oc, and the mean minimum and maximum oxygen solution changed between 6.28 and 6.9 (ppm) in stations 1 to 13, and these amounts were in proportion to the best needs of this type. Also the amount of Calcium, the most important factor for the growth of this type, ranged between 58.29 to 67.93 in 13 stations, and these amounts were ideal, and Calcium did not seem to be a limiting factor for the growth of king prawns in Anzali wetland. The king prawns had a good survival and physiological capacity in PH between 6.5 to 8, and these amounts were in proportion to the mean values ranging from 7.28 to 7.87 obtained from the stations in questions. It can be stated that the most effective factors in reducing the reservoirs of king prawns of Anzali wetland were the increased rate of water pollution, diseases, and probably recent droughts, the immigration of Macrobroachyim and Azola, the release of fish cubs called Zander, the increased number of hunters, the reduction of average depth of wetland, sedimentation and retention times of salinity in this Habitat, especially during the past two years.
    Keywords: Anzali Wetlan, Fresh Water Shrimp, Astacus Lptodactylus, Wetland Potential