Khosro Shahbazi; Borzoo Yoosefi
Abstract
Therefore, in order to evaluate the cultivability of forage cactus (Opuntia ficus indica L.) in the Naft shahr of Qesir shirin city, Kermanshah province has been considered. Different treatments without irrigation, 1, 15, 30 days, once irrigation in three repetitions for three years were performed based ...
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Therefore, in order to evaluate the cultivability of forage cactus (Opuntia ficus indica L.) in the Naft shahr of Qesir shirin city, Kermanshah province has been considered. Different treatments without irrigation, 1, 15, 30 days, once irrigation in three repetitions for three years were performed based on a completely randomized block design. Cultivation of cactus plant in the first half of November and irrigation began on the first of June. The means of the results were compared using Duncan's multiple range test in SPSS software.The results of analysis of variance showed that the effect of irrigation cycle and the interaction effect of irrigation cycle at the time of measurement on the number of pads and plant height had a significant effect at the statistical level of 0.01. Survival of 75, 57, 43 and 38% of plants was obtained with 15-day irrigation cycle, 30-day treatment, one-time irrigation and no irrigation treatment, respectively. The results of this study show that planting cactus in areas with arid desert climate such as Qesir shirin and Somar in Kermanshah province is recommended due to its high adaptability. Dry forage production Cactus forage can be effective for livestock development in these and similar areas. Also, due to the role of cactus in soil conservation, it is possible to prevent the occurrence of dust, desertification, pasture destruction and soil erosion in the region by developing crops. Also,
Mohammad Ansari Ghojghar; Masoud Pourgholam-Amiji; Shahab Araghinejad; Iman Babaeian; Abdolmajid Liaghat; Ali Salajegheh
Abstract
It is clear that the ENSO phenomenon affects the hydrological and climatic regimes in different parts of the world, but the extent of this effect in different parts of the world has not yet been answered. Therefore, this research has been done to answer this important question. In this research, using ...
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It is clear that the ENSO phenomenon affects the hydrological and climatic regimes in different parts of the world, but the extent of this effect in different parts of the world has not yet been answered. Therefore, this research has been done to answer this important question. In this research, using the Oceanic Niño Index (ONI), the effect of the positive phase of the El Niño-Southern Oscillation (ENSO) on the Frequency of Dust Stormy Days (FDSD) in 12 synoptic stations located in Khuzestan and Sistan and Baluchestan provinces over a period of 40 years (2019-1980) has been reviewed. For this purpose, hourly dust data, codes of the World Meteorological Organization, Adaptive Neural-Fuzzy Inference System (ANFIS) and time changes of FDSD index in two neutral phases and the occurrence of El Niño were used. The results of ANFIS model estimation and observational values of FDSD index showed that at the occurrence time of El Niño in Khuzestan and Sistan and Baluchestan provinces, equal to 33 and 17 events, respectively, the observable values of the frequency of days with dust storm were less than the estimated values. The results also showed that the positive phase of ONI is more effective on dust storms in Khuzestan province than in Sistan and Baluchestan province. Therefore, during the hot phase of ENSO, more measures should be taken to control and manage dust storms and their destructive effects in areas where the source of dust storms is external.
Serveh Darvand; Hassan Khosravi; Hamidreza Keshtkar; Gholamreza Zehtabian; Omid Rahmati
Abstract
The purpose of this study was to compare machine learning models including Support Vector Machine, Classification and Regression Tree, Random Forest, and Multivariate Discriminate Analysis to prioritize susceptible areas to dust production. To determine the dust days, hourly meteorological data of Alborz ...
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The purpose of this study was to compare machine learning models including Support Vector Machine, Classification and Regression Tree, Random Forest, and Multivariate Discriminate Analysis to prioritize susceptible areas to dust production. To determine the dust days, hourly meteorological data of Alborz and Qazvin provinces and satellite images of the same days for the period 2000 to 2019 were used. 420 dust collection points were identified and the map of their distribution was prepared. The maps of factors affecting the occurrence of dust, including landuse map, soil orders map, slope map, slope aspect map, elevation map, vegetation map, topographic surface moisture, topographic surface ratio, and geology mam were prepared. Using the mentioned models, the impact of each of the effective factors of dust was determined and prioritization maps of dust harvesting areas were prepared. Models were evaluated using the ROC curve. According to the results, the elevation factor is more important in all models than the other parameters used in the model. The modeling results also showed that the Random Forest )RF( and Multivariate Discriminate Analysis (MDA) models had the highest values of accuracy (0.96), precision (0.94), Probability of Detection (POD) (0.98), and False Alarm Ratio (FAR) (0.051) compared to the others. The performance of the RF and MDA models is better than the other models, followed by the Support Vector Machine (SVM) and Classification and Regression Tree (CART) models, respectively. Also, in evaluating the models using Receiver Operating Characteristic (ROC), the RF model was selected as the best model.
zeinab nazari; nematollah khorasani; sadat feiznia; mahmoud karami
Abstract
One of atmospheric phenomena of dry and semi-dry areas and areas adjacent to these areas is the phenomenon of dust and production of particulate matter (PM10) that have many environmental hazards. The purpose of this research is determination of chemical composition and source identification of elements ...
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One of atmospheric phenomena of dry and semi-dry areas and areas adjacent to these areas is the phenomenon of dust and production of particulate matter (PM10) that have many environmental hazards. The purpose of this research is determination of chemical composition and source identification of elements in aerosols in city of Kermanshah. Enrichment factor are used to identify natural and anthropogenic sources of these elements in aerosols. Tracing of sreams is performed using contour line in level of 500hpa . Samples of aerosols is analyzed for 20 elements by ICP-OES. According to this study, The elements such as iron, potassium, calcium, selenium, arsenic, cobalt, phosphorus, magnesium and sodium have low EF- values, this indicates that these elements have originated from the crust. These elements account for 84% of the total concentration of elements. This shows that crustal elements are the main contributor to the elements in PM10 in the Kermanshah atmosphere. The results of this research show that the most frequent pass of streams to west Iran; west to east of Iraq is in the first rank, then, westnorth to eastnorth of Jordan, east to westsouth of Syria and east to west of Mediterranean. Therefore, it can be stated that Iraq and its neighboring regions have important role in production of aerosols.
Soheila Pouyan; Mohammad Zare; Mohammad Reza Ekhtesasi
Abstract
Dust event is one of the common and destructive phenomenon in arid and desert regions. This phenomenon has negative impacts on human life and environment. Dust storms, in addition to soil loss, can cause and aggravate health problems, food production reduction, economical damages into the industrial, ...
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Dust event is one of the common and destructive phenomenon in arid and desert regions. This phenomenon has negative impacts on human life and environment. Dust storms, in addition to soil loss, can cause and aggravate health problems, food production reduction, economical damages into the industrial, agricultural and communication sections. Therefore, accurate investigative of this phenomenon is necessary. The aim of this research was regional analysis of dust storm index (DSI) in 44 meteorological stations of Iran. At first stage, the dust storm index for each station was calculated using hourly dust data. Next, monthly averages of dust storm index (DSI) were used for regional analysis using linear moments approach. Based on regional analysis, the study area is divided to six homogeneous dust storm index regions. Pearson Type III (PE3) and Generalized Logistic (GLO) distribution models were the best regional distribution models for 1, 4, 5, 6 homogeneous regions, and 2, 3 homogeneous regions, respectively. Estimation of the dust storm index and its regional analysis can be used in many environmental studies, decision making and management processes in relation to combating desertification and dust storms.
Yousef Azimi; Salman Zare; Hamid Sarkheil; Javad Bodaghjamali; Siayamac Heshmati
Abstract
Mulching on the ground surface is one of the common approaches for fixing the sandy dunes and controlling dust. Despite the frequent use of oil mulch, due to its heavy costs and environmental problems, researches are focused on producing new environmentally friendly mulches. In this research, different ...
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Mulching on the ground surface is one of the common approaches for fixing the sandy dunes and controlling dust. Despite the frequent use of oil mulch, due to its heavy costs and environmental problems, researches are focused on producing new environmentally friendly mulches. In this research, different treatments of cement, lime, wind sands and steel-slag, as cement-slag mulch, have been used to fix the sand dunes samples prepared from Robat-Karim region. Steel-slag is added to the mulch composition because of the benefits of waste reduction from environment and replacement of a part of the cement in the mulch composition because of Steel-slag pozzolanic property. To reduce the number of tests and find the optimal composition of the mulch, statistical mixture design approach was used. Furthermore, the effect of different percentages of the ingredients on shear, compression and impact strength and moisture content of cement-slag treatments were investigated. Results show that the addition of steel-slag increases the compressive and shear strength as well as the ability to maintain soil moisture in the proposed mulch. Finally, developing the mathematical model of the experiments, six different objective functions were considered for optimizing the composition of the proposed cement-slage mulch. As a result combination of 68.731% sand, 27% cement, 2.979% steel-slag and 1.3% lime were the best mulch considering all the objective functions. To validate the results of the optimization, six optimal compositions were re-constructed and the tested again. Obtained results showed an acceptable consistency between the predicted and tested values.
TAYYEBEH MESBAHZADEH; nahid alipour
Abstract
Dust phenomenon is one the problem that is developed due to human interference and unreasonable utilities from natural resources and their destruction. In this review, the dust phenomenon frequency was done using selected synoptic stations statistical in Alborz and Qazvin provinces during 2000 to 2014 ...
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Dust phenomenon is one the problem that is developed due to human interference and unreasonable utilities from natural resources and their destruction. In this review, the dust phenomenon frequency was done using selected synoptic stations statistical in Alborz and Qazvin provinces during 2000 to 2014 that annual frequency was evaluated by extraction of dust codes from meteorological data statistically. In order to study of velocity and direction of region winds, wind rose and storm rose of Karaj and Qazvin stations were drew and prevalent wind direction was determined that it showed prevalent wind is northwest and southeast at Karaj and Qazvin stations respectively. Study of the effect of drought on dust phenomenon event was done using SPI, PNI, ZSI indicator for annual scale and was evaluated via SPSS software. The drought result show that 2013 was the driest year at Karaj station and the SPI, PNI and ZSI values were obtained -1.64, 58 and -1.39 respectively. Also 2008 was the driest year at Qazvin station and SPI, PNI and ZSI values were calculated -2.34, 50 and -1.99 respectively. With studying of annual dust frequency with regard to 06 and 07 codes detected that totally 169 days was reported as day with dust at Karaj station that 2012 and 2014 had the most event frequency. Furthermore, totally 115 days with dust accrued at Qazvin station that 2011 with 23 days had the most event frequency.
Shirin Mohammadkhan
Abstract
The phenomenon of dust storm causes a number of damages such as aggravation of heart or lung disease, air and land traffic. Occurrence of dust storm has been growing inrecent years and has created many problems in some cities of Iran. Dust storms of Iran arise either from internal or external sources. ...
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The phenomenon of dust storm causes a number of damages such as aggravation of heart or lung disease, air and land traffic. Occurrence of dust storm has been growing inrecent years and has created many problems in some cities of Iran. Dust storms of Iran arise either from internal or external sources. In this paper, Climatology of dust storms in Iran is compiled based on observational data of 112 meteorological stations from 1985 to 2005. Results show that the total number of dust stormy days varies from 11 to 3833. Accordingly, we have identified five types of cities; 1- less than 492 days; 2- from 588 to 1153 days; 3- from 1243 to 1757 4 days; from 2007 to 2239 5 days; 5- more than 3832 days. Afterwards, we examined each of them separately. The first group is fixed. Cities of this group are located mostly in North, East and Center of Iran. The second group contains three parts:First, an ascending trend to 1992 and then a descending part to 1998 and again,an ascending part to 2005. Cities of second group are located in the southern pasrt of the country. The third group contains four parts: First, a down trend to 1990 and then an ascending part to 1993 and again, a descending part to 1998 and finally, a branch of the ascending to 2005. Cities of the third group are located almost in the southwest. The cities of the fourth group are located in Sistan&Baloochestan province and are affected by the120-day wind. The occurrence of dust storm in the fourth group is ascending. Finally, using GIS and interpolation systems, we have plotted dust storm zone classification map of Iran from 1998 to 2005.
