جستجوی مقالات مرتبط با کلیدواژه « khorramabad » در نشریات گروه « آبخیزداری، بیابان، محیط زیست، مرتع »

Sediments can be sensitive indicators for monitoring contaminants in aquatic environments. Therefore, understanding the mechanisms of accumulation and geochemical distribution of heavy metals in aquatic systems and providing basic information for judging environmental health risks, spatial study of metal concentrations in sediments and their comparison with non-contaminated bases is of great importance. One of the common methods of soil pollution assessment is the use of pollution factor index (CF). The calculation of this index requires determining the background of the elements under study. For this purpose, statistical methods based on mean and standard deviation of data are commonly used. Due to the skuwness of the distribution of geochemical data, the use of this parametric method is limited, so the use of methods resistant to outlier data can be proposed as an alternative approach. In the last two decades, the fractal method has been used to separate communities in data related to many disciplines of earth sciences. In order to evaluate the two mentioned methods, 770 samples of waterway sediments containing six metal elements of As, Cr, Cu, Ni, Pb and Zn were collected in an area that is located in the north of Khorramabad. The background of the elements was determined by both methods (statistical method resistant to outlier data and fractal method) and finally the CF index was calculated. This index based on statistical methods assessed at the intermediate level for arsenic, chromium, copper, nickel, lead and zinc 7.5, 0.8, 5.5, 0.5, 4.7 and 9.2 percent, respectively. For the mentioned elements based on fractal method, the medium level of contamination were 39%, 28.9%, 88.6%, 39.4%, 45.7%, 73.4% of the total sample, respectively. In addition, with the second method, 3% (copper), 0.1% (lead) and 4.3% (zinc) of the number of samples have been evaluated at a considerable level. The results showed that the use of statistical methods in determining the background of the elements, despite the selection of a statistical method appropriate to the distribution of data, has reduced the sensitivity of the pollution index and reduced the efficiency of the index in the separation of pollution classes. While the use of fractal method due to considering the spatial dimension (area) in separating different background communities from anomalies leads to better efficiency of CF index and thus improves regional pollution estimates.

The phenomenon of dust has caused many environmental problems in the western half of Iran. Therefore, recognition of this phenomenon from two aspects of quantity and quality is necessary. This study investigates the ions ratios as well as the morphology of dust particles in order to determine the possible sources involved in dust-fall. Sampling was carried out for one year through the passive method in Sanandaj, Khorramabad and Andimeshk cities.the measured components using Ion Chromatography were evaluated by Cl-/Na+, Mg2+/Na+, and NO3-/SO42- ratios.The resulted data were also analyzed using Exel-2016 and Spss-ver 23 softwares. The results showed that calcium ion has got more percentage average in comparison with other cations in the three stations (3.684%, 5.488%, 4.444%). An-ions have similar average percentages for the three stations. High percentages of ions in dust-fall confirm soil origin and role of evaporites in dust-fall phenomenon. Average of Cl-/Na+ in Sanandaj and Andimeshk stations (0.432, 0.815) were found to be less than seawater standards (1.17). Mg2+/Na+ ratio was higher than the standard of seawater ratio (0.23) for the three stations. Investigation of ratios of the measured ions also showed that dust-fall particles are originated from drylands (transboundary and inland dust production areas) particularly wetlands currently dried because of drought condition and during transportation, by air flows admixtion of ions by different actions are face changes, reactions , and fluctuations. The size of dust were likely to get small by diverging of their shaping origians (transboundary dusts).So the average of dusts size were sanandaj 7.9, Khorramabad 8.9 , and andimeshk 10.6 micrometer. Morphology of the particles was round sphere, semi-sphere , and angular shapes.

Use of flood distribution as a tool to reduce flood damage associated by optimizing the exploitation of floods to restore natural resources and environmental resources has been fashionable in many parts of the world. Considering the number of parameters identifying zones or areas appropriate for flood spreading plans، particularly aimed at feeding aquifers، the use of modern methods of production and new methods of synthesis and the decision making is inevitable. In this study، the Central Plains Khorramabad was selected as the study area. Method in this study is based on a hierarchical analysis process. The purpose of this study is the use of decision support systems and geographic information systems in order to achieve the appropriate places to distribute floods، and after identifying the criteria، indicators and sub-indicators associated by targets (based on the review of internal and external sources)، the mentioned criteria، indicators and sub-indicators were weighted using the AHP and the priority of each criteria and sub-criteria was identified. The study includes four main criteria، 11 indicators، and18 sub-criteria. In this study، the weights of the main criteria were considered identical. The results showed that for 11 indicators، the highest and the lowest weight is related to physical damage index and aquifer parameters، respectively. For 18 sub-indicators in this study، the highest and the lowest weight is related to Sub-criteria of the flood event number and Sub-criteria of water needed for industrial activities. Assessment of appropriate regions to distribute flood in the topographical viewpoints showed that most of regions occur in range of 1200 meters، in east aspect and in >10% slope class. Results of region zoning to distribute flood showed that the highest and the lowest of the study area occurs appropriate and most appropriate class for flood distribution.