Year:2006 | Volume:19 | Issue:2 (71 IN NATURAL RESOURCES)|Papers Count:14

Because of the importance of poplar plantation and difficulties of pure plantations in reducing soil fertility growth and qualitative properties have studied in pure and mixed plantations of Populus deltoids Marsh. and Alnus subcordata C.A.Mey. in north of Iran. The experimental study stablished in complete random block with five treatments and four replecates. The treatments are pure plantations of populus and alnus and mixed plantations of 67% populus: 33% alnus, 50% populus : 50% alnus, 33% populus: 67% alnus. P. deltoides in mixed plantation had higher diameter at breast high and total high and better pruning high and crown diameter than pure ones. Finally we can conclude that the use of mixed plantation of A. subcordata as a nitrogen fixing tree with P. deltoides is useful.

In order to the study of the effect of forest management on biodiversity of woody species in Ardabil, Fandoghloo forest was selected. The forest zone was 178 ha including three sites of Asighran, Fandoghloo and Palutligh. For this purpose 30 square sampling plots (10x10m) were selected using randomized systematic sampling. The silvicultural and biodiversity characteristics included number of trees per hectar, species types, canopy cover, storeying, the percent of grass species, the percent of coppice and seedling trees. Biodiversity invenstories were performed by important biodiversity indices such as Simpson diversity, Menhinick richness and Peet everness. The data analyzed by x2. The results show the biodiversity indices in Palutligh were more than other sites. Because the silvicultural operations were not performed normally in Asighran and Fandoghloo sites.

In order to study the regeneration in natural gaps, 15 gaps were selected in Asalem forests. The shape and gap size were recorded and one transect was established along the widest diameter of each gaps. Each transect was divided into plots 1m2. Quantities & qualitative characteristics of saplings of different species were studied in every second plot. Result showed that the least and the most of the size of gaps measured, they were 89 and 2279 m2 respectively. Evaluated gaps from geometry point of view were not followed regular shape, but they mostly closed to circular and oval shape. So that 54% of gaps belong to this shape. Seedling frequency between the gaps were statistically significant .So that by increasing the gap sizes the number of beach (Fagus orientalis) and hornbeam (Carpinus betulus) sapling reduced but maple (Aeer velutinum)saplings were increased. Also sapling qualitative between the gaps was statistically significant.

Taxus baccata is an endangered forest tree species which its regeneration is very low. Embryo culture carried out to find a practical method for seedling mass propagation. Seeds collected in December 2004 from its natural stand at Zarrin gol valley of Ali Abad Katol in Golestan province, Iran. The seeds were immersed under running water four treatments used to sterilize the seeds. The best treatment (a=%1) was Benomyl 1%. ethanol alcahol 70%, Sedium hypochlorite 3% and mercuric chloride 1%. Sixty seven percent of the treated seeds were uncontaminated from bacteria and fungi. Based on the method experienced in these research embryos separated from the seeds walls and endosperm. As a result many embryos were tested under inviro method at short period. The embryos were cultured on Ms Containing casein, yeast, ascorbic acid and activated charcoal (0.1, 1.0, 0.1 and 5.0 gr-1 respectively). Plantlets were recultured every two weeks in order to increase the shoot height to 5cm. Monthly growth rate of plantlets was 0.7cm. The plantlets were transplanted to jiffy plate after few reculturing then watered at two first weeks with liquid Ms Nutrition solution containing antibiotic (Carbonicilin). In order to increase root development, the young plantlets growing in jiffy Plate were treated with IBN and NAA (1.0 and 0.5mg-1 respectively) after two weeks and enough growth (shoot and root) plantlets were transplanted in to soil and kept in a growth room for three months at 25°c for 14 hours in light and 17°c for 8 hours in dark. All seedlings had normal growth.

Flood studies to plan for optimal utilization and to control this natural phenomenon is main concern in the world and our country. Great damages caused by floods in different parts of the country during past few years demand comprehensive plans; knowing that it is impossible to Plan and apply flood control methods without a good knowledge about the behavior of this phenomenon. The extend of flood damages in various conditions depends on the amount of inflow and the geometrical characteristics of flow bed and adjacent areas. Thus flood hazard zonation for different return Periods 'is necessary to predict the extend of damages caused by floods in different conditions and to justify socio-economical aspects of flood control programs. To Plan optimal land use in river margins and flood plains, the prohibitive, restrictive and it is impossible to zone flood hazard plain without a good knowledge of flood intensity and torrential flow behavior along the river route and flood plain. As a result, regarding more adaptation between estimated hydrographs by SCS method and observed hydrographs, this method was selected to estimate flood hydrographs, in related sub basins for given return periods. After this stage by estimating the outlet flood hydrograph in the headwaters and existing sub basins along given route for determining flood hazard plain by SCS method of HEC-1 Model, maximum water levels in 28 distinct cross sections were determined by MIKE11 model along about 14 kilometers of the river route. In the end, by using digital elevation model (DEM) produced from river bed and boundaries and the maximum water level in given cross sections for return periods of 5, 10, 25 and 100 years the flood hazard plain was determined by ILWIS Software Capability.

Stream flow is one of the main components of water resource. Therefore stream flow forecasting is very important especially in drought years. Impact of climatic signals on stream flow to forecast the amount of flow in lead time is a new subject in international research center. In order to investigate this subject Lake Oromieh basin was selected. From many hydrometric stations in the basin, 9 stations that have long term data selected. A method has been devised to incorporate SOl, PDO and NAO, to forecast the spring stream flow, one year in advance. Spring season river flow forecasting is very important, since major portion of annual flow occurs in spring. The method could be used by water planners in better planning and management of available water resources. To accomplish this task, first impacts of the climatic signals on stream flow in Oromieh Lake basin was investigated. There are many hydrometric stations, of which nine with long term data were selected. From numerous climatic indices that were studied in this research six were selected based on statistical tests. These indices include SOI, PDO, PNA, NAO, NINO3, 4 and NOI. In order to determine the impact of climatic signals on stream flow, several time steps including monthly, seasonal and annual were explored. The results show that seasonal time steps have higher impacts than annual or monthly ones. Furthermore, some of the negative and positive phases of seasonal indices indicate higher correlation with stream flow. However, real significant relations are not revealed until the joint effect of some indices is studied together. This is done through a method that takes one index (in either phase) and observes the behavior of the stream flow by instances of the other index for the cases were the conditions of the first index are fulfilled. A remarkable progress in terms of correlation coefficient is observed when this method is employed. This research shows negative SOI, positive PDO and NAO indices have higher correlation with spring stream flow than other indices. Evaluation of forecasting values show positive PDO indices is good predictor for Spring stream flow in this basin.

Zataria multiflora Boiss. with the persian name of Shirazi Avishan is an aromatic plant that grows wild in southern regions of Iran. In this research anti-microbial effect and chemical composition of the essential oil of this plant was investigated. The aerial parts of Zataria multiflora were collected in full flowering stage from Shiraz in Fars province. The essential oil was extracted by hydro-distillation and analyzed by a combination of GC and GC/MS. The results showed the high percentage of anti-microbial components like thymol (52.4%) and carvacrol (6.1%). For study of antimicrobial effect of Z. multiflora, the oil was diluted by DMSO at 1%, 2.5% and 5% and tested against two kinds of Salmonella paratyphi (A and B) by disk diffusion method. The results showed, the oil by concentration of 1%, 2.5% and 5% inhibited the growth of Salmonella paratyphi A at 0, 9.3 and 15.6mm, respectively. The growth of Salmonella paratyphi B was inhibited by the 1%.2.5% and 5% of the oil, at 8, 8.6 and 21.6 mm, respectively. The results showed the high anti-microbial of Z. multiflora oil.

In order to determine capability and efficiency of synthetic unit hydrograph (Snyder, SCS, Triangular & Clark) for flood simulation, this investigation was carried out in Sikhoran basin (Hormozgan province). For this propose, natural and synthetic unit hydrographs based on rainfall and runoff data were calculated and analyzed, and also comparison was made between the four methods and observed hydrograph. The visual comparison showed that Snyder method is better than the other three method and error of mean and mean relative logarithmic error of peak flow and time to peak and model efficiency is lower than the other methods. In previous investigations showed that Snyder method is suitable for mountainous basins with steep slop and SCS method and Triangular method are suitable for flat basins with slow slope as well.

Tribe boragineae of boraginaceae have a twenty species in Iran and extensive dispersal. In this study five species of Anchusa L andninespecies of Nonea medicus. Gainful of taxonomic qualities were review. Taxonomic qualities by striomicroscopy showed that achene axis in A. aegyptica L. DC., A. strigosa labill., A. italica Retz of Anchusa L. and N. lutea desr. Reichenb. ex DC., N. rosea m.B link. of Nonea medicus. is erect and in A. aggrgate lehm,. A. arvensis L ehm, N. Suchtelenoides H. Riedl. N. persica boiss, N. caspica willd. G.Don, N. pull L. DC., N. turcomanica m. Pop., N. anchusoides boiss & bushe, N. flavesence C. A. mey. Fisch. & C.A.Mey. is ovate. Study of pollen grains by L. M & S.E.M. Indicate pollen grain type in both Anchusa L and and Nonea medicus is tetracolporate exceptionally in A. aggrgate lehm. Is hexacolporate, is poolar and colporate. Flower style is gynobasic. In corolla between lobes and tube scale observed.

In this research, the autecology of Agropyron cristatum in three ranges of elevation were investigated at Golestan National Park where has the mean annual temperature of 130°c and the mean annual rainfall of 185 mm. Phenological stages, cover, and production of this species were determined by using at least 20 plants and 10plots of 1-m2 in each of range of elevation. Some characteristics such as height of growth, length and width of spikes, germination percentage, and weight of 100 seeds, chemical elements and pH of soil were measured. Vegetative growth of this species was started at late March to late April and heads out at late May. This species went to full flower at mid June and seeds were ripening at late June to mid August. Seeds will be disseminated at late August to mid September. It had also fall regrowth in autumn. The contributions of this species towards the total canopy cover and production of the study area were 13 and 16 percents respectively. The germination percentages of this species under 10°c, 20°c and 30°c were significant (p<0.05). The maximum germination rate was 80.6% at 20°c in elevation range of 1200-1400m and the minimum germination rate was 29.6% at 10 C in elevation range of 1600-1800m.The weight of 100 seeds was 0.162 gr. The chemical and physical elements of soil including N, P, K, pH, texture, and structure were not significant at different elevations (p>0.05). This plant usually grows in soil having granule structure and loamy texture. The maximum root depth was about 35 cm. The identification keys of this species with closely pressed spikelets and tinged purple awns approve the name of Agropyron cristatum. This species was erroneously named Agropyron pectiniforme in Iran.

This research has been designed to approach a proper irrigation method for green space development and gardens expansion in desert areas. The area has desert soils with heavy texture and high salinity on surface. Climate is cold arid, mean annual precipitation and evaporation are 62 mm and 3500mm respectively. In these project four main treatments of pitcher irrigation, 10 cm diameter trickle tube, 15 cm diameter trickle tube and drip trickle irrigation with four secondary treatments of Pinus eldarica, Fraxinus excelsior, Pistacia vera and Punica granata species were carried out. There were determined the growth rate and amount of water consumed in each irrigation methods. The results showed the irrigation methods at 5% (P<0.05) and kinds of plants at 1% (P< 0.01) have significant difference. Comparative results between averages of height and canopy diameter indicated the superiority of 10 cm-diameter trickle tubes irrigation. Among the secondary treatment, Punica granata, Pinus eldarica and Fraxinus excelsior gained mentioned method. Pistacia vera had maximum growth with 15 cm diameter trickle tubes irrigation, but there was no significant difference with 10 cm diameter trickle tubes irrigation method (p<0.05).

Plane tree (Platanus orientalis) as native long lived and fast growing tree is suitable for planting in cities and afforestrition. But it has problems in terms of propagation. So, in this investigation different kind of two years cutting including; three size <9mm, 10-15 and 16-25mm diameter with two or three buds vertically and one bud outside of soil selected and cutting planted into nursery with loamy soil. Growing buds and vitality considered as evaluation indexed and measured 10 day after planting for eight periods. There are significant differences between cutting with differences diameters for vitality, large (77%), medium (57%) and small (31%). There were also differences between cutting with two buds (31.5%) and three buds (69%) in terms of vitality. By calculation the mean vitality value of the last measurement were cutting with large diameter and three buds (91%), cutting with medium size and three buds (75%) and small cutting with two buds (19%). the result showed the large cutting of two and three buds and the medium cutting of three buds are recommended for producing seedling in nursery.