جستجوی مقالات مرتبط با کلیدواژه « sarkhoon plain of hormozgan » در نشریات گروه « محیط زیست »

Increase inwater demand will likely be followed by increased pressure on groundwater resources in the short term and long term. At this time, spreading floods on the aquifers is one of the appropriate methods tocontrol and optimal use of floods and artificial recharge of groundwater resources in arid and semi-arid regions. Sarkhoon plain is one of the plains close to the center of HormozganProvince whereits groundwater has been supplyingthe regional needs for water, so far. A look atthe hydrologic statistics of recent years indicates negative water balance in the plain.Thisreveals the importance of sustainable management of water in the region. The purpose of this study was to determine the importance of factors effective in identifying the areas prone to artificial recharge in Sarkhoon plain by using network process analysis and determining appropriate areas for operations of artificial recharge using GIS in combination with the network process analysis. Thus, byidentifying the areas prone to spreading floods and proposal for constructing structures, the wasting of water resources in the region will be prevented. Thus,some progress can be made in planning for sustainable development of water resources.
Sarkhoon study area is located at almost 25 km from Bandar Abbas, HormozganProvince, with an area about 11,400 ha. The estimated average annual rainfall valuesin theplains were234 mm and 219 mm, respectively. The groundwater level changes in Sarkhoon plain during a period of 25 yearsfrom1990-1991 to 2013-2014 accounted for 0.5 m of the annual drop.( pic1)
Materials and In this study, 9 influencing factors of slope, water quality, water depth, permeability rate, alluvium thickness, land use, transferability, geomorphology and the drainage density were selected and analyzed. Then, the paired comparison method to determine the weight of classes of each layer and the ANP method were used todeterminethe final weight of the criteria. The Super Decision software was also used to determine the weights. After omission of the areas with limitation, the areas prone to flood spreading operation were determined.The appropriate criteria for flood spreading operation in SarkhoonPlain are:Slope: To prepare the slope layer, the digital elevation model (DEM) with a pixel size of 30m is extracted from ASTER data.(pic 2)
Geomorphology: From the morphological map of the province, the study area was separated and divided into four classifications.(pic 2)
Water depth: Water depth map was obtained with minimum error using the 10-year average water levels data related to observation wells and generalizationto the whole plain using interpolation algorithm by Kriging spherical model.(pic 2)
Alluvium thickness: The mentioned layer was re-classified into four classes. (pic 2)
Alluvium transferability: The water transferability map of Sarkhoon plain water was prepared according to the existing pumping test results of 10 Piezometers in the plain (Hormozgan Regional Water) with interpolation by Kriging spherical model in the ARCGIS 10 platform.(pic 2)
Land use: The land-use layer for the study area was obtained from 1:25000 maps and updated by using ASTER satellite images combined with bands 1, 2, 3 as well as Google Earth images, and were classified into four categories.(pic 2)
Water quality: In this study, the data of observation wells wereused to provide the electrical conductivity layer of Sarkhoon plain area.(pic 2)
Drainage density: The cumulative flow layer was extracted from regional DEM, and then, the channel density layer was obtained. It was classified into six classes.(pic 2)
Permeability coefficient: To determine the permeability of the study area, the tests results provided by the Agricultural Research Center of Hormozgan province in 2009 were used, and the permeability layer was produced by interpolation.Itwas also re-classified into 5 categories.
Identifying the areas with limitation: In the present study, according to research in this field and the region local conditions, three layers of slope, geomorphology and land use were identified as layers with limitations.
Analytic network process (ANP): This model is one of the multi-criteria decision-making techniques classified in compensatory models series. The most important distinction between this method and the hierarchical approach is in the influenceand effectiveness of criteria on one another. Inthis hierarchical structure model, a target or a node is initially located that finally ends to a destination node or cluster. Therefore, there is a linear structure from top to bottom and without returning from lower or higher levels. But in the network structure, the network and its clusters are not distributed on a regular basis. In addition, there should be the possibility of a cluster being influenced by itself (interdependence) or affectinganother cluster (external dependency).Direct returning from the second cluster or passing through the middle cluster is possible.
Results and Examination ofthe weights of criteria in this study indicatedthat the drainage density factor with a weight equal to 0.274 is the most important factor in locating of flood spreading in SarkhoonPlain. After integration, the value of each cell was determined. To attain better results, using the natural breaks method, the whole land was divided into five final categories based on the zoning map. From the total area of Sarkhoon plain, about14.2576 square kilometers and 45.0283 square kilometers were determined as very suitable and suitable areas,respectively, for flood spreading operation. The results indicatethat most of the perfectly suitable and suitable areas occur in the category of 0-3% and 3-5% regarding the slope. Regarding the measure of depth, the perfectly suitable and suitable areas are located at depths greater than 68 meters. Also, these areas are in accordance with the ranges with higher transmissibility rates. Regarding thickness measure, the alluvium is located in a range greater than 60m. Also, the zones are located in the areas with higher permeability coefficients (18-24 and 24> m per day). Regarding electrical conductivity layer, the suitable and perfectly suitable areas are located within the scope with EC less than 2000 micromhos /cm. In terms of land use layer, the lands are located in the areas with pasture usage and drainage density less than 3.8 km per square kilometers.
Planning to use floods, meanwhile to reduce their destructive effects, will provide a new water source for the consumers. In the studies with similar research subject, the AHP method was used to determine the weights of criteria in such method.The criteria relations and their coefficient of impact are not considered to reduce the accuracy and quality of the work. Since the ANP method deals with the dependencies systematically, i.e., it considers all internal and external dependencies between the elements and clusters for analysis, but other methods consider these relationships. Thus, withthe interdependence of environmental issues (including this study subject), the use of ANP method can provide the necessary supports for decision-makers and planners tosolvewater management issues to gain a deeper understanding of environmental issues.