جستجوی مقالات مرتبط با کلیدواژه « gorgan » در نشریات گروه « منابع طبیعی »

Increasing wheat yield requires an understanding of appropriate management method that are Increasing wheat yield requires an understanding of appropriate management method that are most important sowing date and appropriate cultivars. Evaluation of yield and grain filling rate of bread wheat promising lines to normal and late seeding dates, this experiment was carried out at Gorgan research station during 2015-2017. The experiment was a spilt-plot based on RCBD with three replications. The main factors was two sowing date December 15th (normal seeding date) and January 15th (late seeding date) and the second factor were eight genotype and cultivar of wheat. The results of combined analysis of variance showed that the effects of year, sowing date and interaction effects of year × sowing date were significant on all of traits under study expect of harvest index. Also interaction effects of year × genotype were significant on all of traits under study expect of number of grains per spike and growth degree day to maturity. The suitability of climatic conditions during plant growth in normal seeding (December 15th) caused more tillers fertilized. On the other hand, the warmth and dryness of the air at the later seeding date reduced the number of fertilized tillers. Results showed that with delay in seeding date, mean of growth degree day to physiological maturity decreased. Also results of mean comparison of interaction effects of year × genotype and of year × sowing date showed that the genotype SAUAL/3/MILAN/S87230//BAV92 and Gonbad cultivar had higher length of filling period and rate of effective grain so produced acceptable yields compared to other.

Management and planning, distributing the economic and social activities as well as clearing hidden capacities in terms of the land’s potential and needs are the main goals of Land use planning. MOLA was used in order to zoning and planning Gorgan and Aliabad cities in eight major Land-uses. The method of analytic hierarchy process (AHP) and analytic network process (ANP) and the experts’ experiences were used for weighting the three main factors including ecological, economic and social factors. Compare zoning based on two ways AHP and ANP weighting also was evaluated. The results showed that the integration of applications based on AHP and ANP different weighting methods. According to the results of the integration of applications based on ANP method compared to the AHP with respect to slope, height, density of vegetation, rainfall and erosion ability in general is more appropriate. The results showed that according to total Kappa values (0.9151), spatial Kappa (0.9524), standard Kappa (0.9323), and chance agreement (0.1111), MOLA based zoning based on AHP and ANP weights had a similarity A lot. But the difference in the use of the AHP and ANP was 88663 pixels (7979 ha). For this purpose, statistical data on slope, height, vegetation density, precipitation and erodibility were extracted based on the weight of the two methods of AHP and ANP. According to the results, the placement of land use based on the ANP method in comparison with AHP is more appropriate in general. This means that the method has better performance in the ANP have been weighted to land-uses. The results of this study, the relationship and the importance of all aspects of ecological, economic and social planning and land use planning notes.

Simulation of runoff resulted from any significant rainfall events can help to estimate the severity of floods. To protect watersheds, application of a model which is able to predict runoff at certain times and places is essential. Therefore, this study aimed to simulate runoff generation in upstream catchments of the Shahrake Behzisti as well as assessing the effect of implementation of vegetation management scenarios, using three relatively intense rainfall events occurred in recent years. The model of physically based Limburg soil erosion model (LISEM) within PCRaster GIS and programming language was applied in this study. In order to run the LISEM model, four basic raster maps of digital elevation model, landuse, soil texture and roads (impervious areas) were prepared. Digital elevation model map of the catchment was extracted from the Ultracam image of 1 m resolution within the ArcGIS environment. During this study, only two events on 2/11/2014 and 16/9/2015 led to runoff generation. Thus, the first event was used for calibration and the second one for validation of the model. Statistical comparison of the simulated and observed hydrographs of the rain events on 2/11/2014 and 16/9/2015 showed the correlation coefficients of 0.80 and 0.76 and Nash-Sutcliffe criteria of 0.8 and 0.5 respectively. The results of the simulation showed that the model was able to predict total runoff, peak discharge, runoff initiation time and time to peak discharge with relatively good performance. The results of the application of the LISEM model showed that runoff volume and peak discharge significantly decreased by implementation of vegetation management scenarios.

Landscape includes a mosaic of landscape elements in a context of a major land use/cover. Much emphasis has been placed on developing methods to quantify landscape patterns in recent years. Landscape elements include various types, including urban areas and patches, which were used for change's identification in the current study. Any urban area has been considered a landscape patch and their patterns for the Gorgan city between the years 1987 and 2001 have been compared in this study. Number, shape and neighborhood metrics was the major groups of metrics calculated. To do so, urban areas were fed to Fargstats Software as patches. Comparison showed that development pattern in Gorgan city has led to the creation of larger and simpler patches with and less fractal dimension during the 14-years period of our study. In fact, urban growth was shown to be adhering to the previous urban patches. This is also visible to the spatial investigation of the largest patches (a complex of continues areas), such that, for example, two large patches in 1987 had been joined because of infill. Despite the tendency of urban growth around previous urban patches and in their vicinity, patches did not show a uniform distribution in the area, rather, they were irregular. This result is confirmed by the fact that the urban area has increased 2.1 times during the study period.