Aliakbar Noroozi; Morteza Miri; Davoud Nikkami; Tayeb Razi; Amir Sarreshtehdari; Ziaedin Shoaei
Abstract
The purpose of this study was to investigate the oak forest dieback with respect to drought occurrence, soil moisture changes and dust occurrences factors in Ilam, Kermanshah, Lorestan and Chaharmahal and Bakhtiari provinces of Iran. The data used were field surveys collected through GPS, MODIS satellite ...
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The purpose of this study was to investigate the oak forest dieback with respect to drought occurrence, soil moisture changes and dust occurrences factors in Ilam, Kermanshah, Lorestan and Chaharmahal and Bakhtiari provinces of Iran. The data used were field surveys collected through GPS, MODIS satellite imagery, GLDAS Soil Moisture, dust and precipitation data of the meteorological stations of the provinces during an 18-years period (2000-2017). The results of the study of greenness values of the forests in the study area showed that the first decline occurred in 2005 and repeated more severely with much wider spatial extent in 2008. Investigation of the relationship between drought events and its spatial and temporal variations with the changes in forests greenness of the study area showed that the reduction in precipitation amount is one of the main reasons for forest greenness reduction in the study area. The increased frequency of periods of rainfall shortage and drought duration, especially at 9 and 12-month time scales, showed a significant relationship between drought occurrences and forests greenness in the study area. The results indicated that by decreasing precipitation drought periods increased, soil moisture decreased, and dust storm occurrences increased. As a result, in most of the years, with decreasing soil moisture and increasing dust storms, the forests greenness of the study area has decreased and vis versa. Therefore, there is a direct relationship between soil moisture and forest greenness while an inverse relationship exists between dust and forest greenness.
Mohammad Jafar Soltani; Baharak Motamedvaziri; aliakbar noroozi; Hassan Ahmadi; Jamal Mosaffaei
Abstract
Extended abstractIntroductionDust event is one of the natural events that occur widely in the world, especially in dry areas. One of the main and effective factors in the occurrence of this phenomenon is the geographical location and climatic conditions of the regions affected by this phenomenon. The ...
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Extended abstractIntroductionDust event is one of the natural events that occur widely in the world, especially in dry areas. One of the main and effective factors in the occurrence of this phenomenon is the geographical location and climatic conditions of the regions affected by this phenomenon. The purpose of this research is to analyze the cause-and-effect relationships of dust events in Hendijan region with the approach of the Driver-Pressure-Situation-Effect-Response (DPSIR) framework. Materials and methodsThe DPSIR process is an analysis based on the "cause-disability" relationship of factors for policy-making and management planning. The DPSIR framework is a systems thinking framework that assumes cause-and-effect relationships between environmental and socio-economic systems. This conceptual framework uses a cycle of causes and results for the proper integration of basic economic, social and environmental data and information, specifies the relationship between environmental processes and human factors, and also leads to an understanding of the relationship between policy levels and environmental studies. The trend of each component of DPSIR was also evaluated by applying quantitative criteria for the time period of 2007-2019. Results and discussionThe results of the research showed that the total index of all DPSIR components has an upward trend for the studied period. The slope of the trend related to D, P, S, I and R components was equal to 0.06, 0.03, 0.02, 0.05 and 0.02, respectively. Although some responses were made to reduce the influence of others. The components of DPSIR have been adopted to improve the dust situation, but the research results and the process of changes showed that they were not sufficient and integrated. In this research, a variety of answers related to the components of the driving force, pressure, situation, and effects were identified. The results showed that dust concentration and dusty days in the region increased during the study period and more attention was paid to reactive responses and less focus on preventive responses. Also, paying attention to the response of increasing the efficiency of irrigation due to the high correlation between the state of dust concentration and pressure factors such as the amount of rainfall, soil moisture, and exploitation of water resources in the research area, special attention to the development of water extraction systems as one of the most important responses. Management issues due to the existence of negative and high correlation with the dust situation during the years of research, adequate and sustainable supply of water resources by reducing and minimizing the diversion dams downstream of the Kowsar and Ask dams due to the increase in dust concentration with the increase of flood diversion operations and construction Reservoir and diversion dams since 2009, Considering the water rights of wetlands in the region with the aim of preventing wetlands from drying up and creating a dust center, especially in the west of Hendijan city, and carefully choosing the appropriate plant species, as well as carrying out desertification operations (planting saplings, mulching, building windbreaks). With the ecological conditions of the region, due to the negative correlation between the desertification operation and the reduction of dust concentration since 2014, it can help to improve the dust situation in the research area. ConclusionIn this regard, it is recommended to respond to driving forces (D) and pressures (P) so that while improving the conditions and adverse effects caused by it, the drivers and pressures that create the current situation can also be controlled. Based on this, the incomplete implementation of the answers is another reason for not achieving management goals and making the situation and the number of dusty days more unfavorable. It is also suggested to implement the integrated watershed management program in Hendijan city through the development of a joint water, agriculture, and natural resources program upstream of the watershed in order to clarify the effective measures of the water production, distribution, and consumption chain in the upstream lands.
Amir Sarreshtehdari; Amin Salehpour Jam; Mohammad Jafar Soltani; Aliakbar Noroozi; Alireza Shademani; Masoud kherkhah zarkesh
Abstract
Determining the effectiveness of flood spreading schemes, especially from the point of view of effective economic and social indicators, over a quarter century after their implementation in the country, plays an important role in their assessment. In this study, indicators related to the effects of flood ...
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Determining the effectiveness of flood spreading schemes, especially from the point of view of effective economic and social indicators, over a quarter century after their implementation in the country, plays an important role in their assessment. In this study, indicators related to the effects of flood spreading plans on Ab-Barik Aquifer of Bam were identified and then ranked based on nonparametric statistical tests from the experts' point of view. For this purpose, first the indicators related to the effects of flood spreading projects on the aquifer based on library studies, expert inquiries as well as site visits and face-to-face interviews with local residents and users were identified and finally the validity of the questionnaire based on expert opinions was identified. Finally, the validity of the questionnaire based on the experts' opinions and their comments was finally confirmed. Also, the reliability of the measuring instrument was tested by calculating Cronbach's alpha component. In this research, based on the multi-response coding method, the variables of the questionnaire were of the type of qualitative and qualitative variables consistent with the Likert scale, so at this stage, a survey was conducted from 30 experts. The range of changes in mean rank values varies from 4.15 to 22.88. The results of the ranking of indices based on Friedman test showed a significant difference in the effectiveness of the effective variables in evaluating flood spreading projects on aquifer, so that the question of “reducing the damage to flood lands and gardens” with the rank mean of 22.88 and also the question of “conflicting among the villagers in the area” with the rank mean of 4.15 have maximum and minimum priority, respectively. In addition, the results of the study indicate the high effectiveness of flood spreading schemes in the Ab-Barik Aquifer of Bam.
Ahad Habibzadeh; Aliakbar Noroozi
Abstract
The aim of this study was to investigate the pitting and contour rainfall harvesting systems and their role in rainwater collection and forage production in rainfed conditions. This study was performed with five treatments of pitting with seeding (B), contour furrows with seeding (A), pitting without ...
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The aim of this study was to investigate the pitting and contour rainfall harvesting systems and their role in rainwater collection and forage production in rainfed conditions. This study was performed with five treatments of pitting with seeding (B), contour furrows with seeding (A), pitting without seeding (E), contour furrows without seeding (C) and control treatment (D) in three replications. FAO standard plots measuring 5x40 meters were considered for the project at Tikmehdash Research Station. In seeded treatments, Agropyron elongatum and local sainfoin were cultivated due to the effects of soil protection and forage production. Statistical analysis of the results was performed using SPSS software in the form of randomized complete blocks. The results of statistical analysis showed that the highest to lowest percentage of total canopy cover is related to contour furrows and seeding treatment with an average of 80%, pitting operations with an average of 78% and pitting and seeding with an average of 80%, respectively. Comparison of the canopy cover and forage production in the treatments showed that the canopy cover in A, B, C, D and E were not significantly different and were in the same group. Production of rangeland and succulent plants was higher in E treatment and was significantly different from A, B, C and D treatments. Also, Treatments A, B and C were not significantly different in rangeland production, but were significantly different from D (control). The highest and lowest forage production of 729.17 and 315.33 kg.ha-1 belong to pitting and control treatments, respectively.
Mahmood Damizadeh; Rasool Mahdavi; Ali Akbar Noroozi; Hamid Gholami; Arshk Hollisaz
Abstract
Dust storms are one of the atmospheric phenomena which has many negative effects for Hormozgan Province, as one of the most important population and tourism centers in the south and with significant and strategic facilities in the country. For this reason, todays determining the hotspots and areas affected ...
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Dust storms are one of the atmospheric phenomena which has many negative effects for Hormozgan Province, as one of the most important population and tourism centers in the south and with significant and strategic facilities in the country. For this reason, todays determining the hotspots and areas affected by the storm, as well as identifying important routes of entry and movement is one of the most important needs of relevant organizations in this province. In order to study the dust phenomenon in Hormozgan Province, first, all meteorological data of 12 synoptic stations in the region between 2000 and 2018 were analyzed and 48 dust storm events were identified that their horizontal visibility has decreased to less than 1000 meters and dust mass detection operations were performed using MODIS satellite images and four detection algorithms of Ackerman, TDI, TIIDI and NDDI and areas affected by storm as well as areas of origin were identified. HYSPLIT particle Lagrangian diffusion model was used to route the motion of the dust storm and the entry routes of dust storms into the province also, its routes and areas that have the most impact in this area were identified. Comparing results of four dust detection algorithms indicated better performance of TDI algorithm compared to other algorithms in detecting the focus and mass of dust in the area. According to the results, eastern regions of Hormozgan Province, Jazmourian Wetland, eastern Sistan and Baluchestan, western regions of Afghanistan and Pakistan, as well as central and southern regions of Saudi are one of the most important centers of dust production in the region. Investigating HYSPLIT model maps indicates the existence of three general routes of entry and creation of dust storms in the area which includes the southwestern regions of the country, the south-north route and the north and northwest route. Also, based on model results, about 53.7% of the path of movement and the release of dust after a storm is to the north and northeast direction which causes the spread of pollution and intensification of dust concentration in cities such as Bandar Abbas, Qeshm, Minab, Rudan, Jiroft, Kahnooj, Bam, Iranshahr, Khash, Mirjaveh and Zahedan. Also, about 22.3% of the storms in the region consider the southern route, 14.8% the south-west route and 9.2% the east route to continue their navigation.
Ali Salehi; Kamran Pourmoghadam; Aliakbar Noroozi; Amir eslam Bonyad
Abstract
In recent years, a considerable part of the western oak forests of the country has been faced with drought and decline. Initial studies have identified one of the factors affecting oak forest dryness as increasing frequency and severity of dust phenomenon. In this study, the MODIS sensors with a resolution ...
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In recent years, a considerable part of the western oak forests of the country has been faced with drought and decline. Initial studies have identified one of the factors affecting oak forest dryness as increasing frequency and severity of dust phenomenon. In this study, the MODIS sensors with a resolution of 1 km and 250 m and meteorological data of Kermanshah Province synoptic stations over a 15-years period (2014-2000) was used to investigate the dust phenomenon and the process of forest vegetation changes in the region. Dust intensity was investigated using visibility data and unsupervised image classification method. Also, in this study, the relationship between the occurrence of dust and vegetation changes in oak forests was investigated. Survey of dust events showed that Kermanshah Province had the highest number of dust events in 2008 and 2009, respectively. The highest incidence of severe dust was in 2012. In addition, satellite imagery and spectral indices also showed that the highest reduction of vegetation in dense forests (>50% canopy cover) by 67% and with an overall accuracy of 62% in the south and southeast of Kermanshah Province and at the border of Lorestan and Ilam provinces has happened. Results also showed that the frequency of dust phenomenon is highly correlated (70%) with the phenomenon of oak forest degradation; and dust has the effect of reducing the greenness of oak forests in Kermanshah province.
Mansour Chatrenour; Ahmad landi; Ahmad Farrokhian firouzi; Aliakbar Noroozi; Hosseinali Bahrami
Abstract
Nowadays spectroscopy is used for estimating soil properties. The main objective of this research was to estimate some soil properties of Susceptible Areas of Dust Production using visible and near infrared. Therefore 142 soil sample of Susceptible Areas of Dust Production were Collected and analyzed. ...
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Nowadays spectroscopy is used for estimating soil properties. The main objective of this research was to estimate some soil properties of Susceptible Areas of Dust Production using visible and near infrared. Therefore 142 soil sample of Susceptible Areas of Dust Production were Collected and analyzed. Equivalent calcium carbonate, gypsum, organic carbon and nitrogen of soil sample were measured and linear regression models of PCR and PLSR were used to estimate these properties .Three methods of reflection of the main spectra and pre-process methods of first derivative and second derivative were compared in two regression models of PCR and PLSR. The results showed that the PLSR method is more accurate than the PCR model for estimating soil properties. The PLSR model in the pre-processing second derivative with noise reduction, showed the highest accuracy for equivalent calcium carbonate, organic carbon and total nitrogen with the coefficient of determination as 0.95, 0.92 and 0.81, respectively. For gypsum, the highest accuracy in the first derivative with the coefficient of determination was 0.87. The results of this research revealed the use of spectroscopy in estimating soil properties of dust production-prone areas in Khuzestan province have an appropriate accuracy; and due to the extent of these areas and the speed of operation and cheapness of this method, it can be used to predict the amount of soil properties in these areas.
Morteza Miri; Mojtaba Rahimi; Aliakbar Noroozi
Abstract
Todays, satellite precipitation data with high spatial and temporal resolution is an appropriate alternative source for conducting various studies of meteorology and hydrology in areas with inappropriate distribution of stations. These data are very important for a country like Iran which is always faced ...
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Todays, satellite precipitation data with high spatial and temporal resolution is an appropriate alternative source for conducting various studies of meteorology and hydrology in areas with inappropriate distribution of stations. These data are very important for a country like Iran which is always faced with problems of water shortage and precipitation. Therefore, the main purpose of this study is to evaluate the accuracy of GPM and TRMM daily precipitation against the recorded daily precipitation data of selected stations in Iran. Statistical methods were used to achieve this purpose. The data used include daily precipitation data from meteorological stations and daily rainfall from latest GPM and TRMM products in the period 2015-2000 in Iran. Statistical analysis showed that the daily precipitation values of these sensors are not accurate in Iran, and the estimated precipitation error is significant for most stations. Comparison of rainfall estimates from TRMM and GPM showed that although there is a great similarity between the estimates of precipitation values of GPM and TRMM, however, GPM data are more accurate than TRMM data in Iran. In terms of location, the best accuracy of the GPM and TRMM databases were observed in west of Iran, especially along the Zagros mountains, and like many other databases, the lowest accuracy was observed in coastal areas, especially along the Caspian Sea. Comparison of total annual precipitation of the stations and the remote sensing databases showed that not only there is a difference between the estimates of precipitation, there is also a spatial difference between high and low precipitation cores.
Zahra Rezghi; Mehdi Homaee; Aliakbar Noroozi
Abstract
Knowledge about soil texture is very important in agricultural studies due to its direct impact on other soil properties. However, determining the soil texture in vast areas requires a lot of time and money. For this reason, researchers are looking for ways to determine this important feature of the ...
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Knowledge about soil texture is very important in agricultural studies due to its direct impact on other soil properties. However, determining the soil texture in vast areas requires a lot of time and money. For this reason, researchers are looking for ways to determine this important feature of the soil on a large scale. One of these methods is the use of surface soil spectrometry. In this method, the choice of calibration method significantly affects the accuracy of measuring the characteristics of the surface. In this study, the performance of two regression techniques, namely, partial least-squares regression (PLSR), principal component regression (PCR) were compared to identify the best method to assess sand, silt and clay. For this purpose, 50 soil samples from Tehran province were collected and used as a data set for Calibration and Validation. Soil samples with different moisture levels (oven dry, 5, 10, 15 and 20 w/w) were scanned using a FieldSpec Pro Spectroradiometer with a measurement range of 350–2500 nm. The spectra were subjected to three pre-processed techniques, e.g., Savitzky–Golay (SG) smoothing, first derivative with SG smoothing (FD-SG), Normalization with SG smoothing (Normal-SG). The R2 results from cross-validation indicated that the PLSR model had a better performance than PCR. Normal + SG pre-processing method for clay loam texture and SG method for sandy clay loam texture showed better estimation of measured properties. The amount of R2 for clay was 0.74, 0.81, 0.97 and 0.87, respectively, in moisture content of oven dry, 5, 15 and 20% in clay loam texture And 0.95 and 0.61 at oven dry and 5% levels in sandy clay loam. Silt was better predicted by R2 0.67 in moisture content of 5% in clay loam texture and R2 0.97 in moisture content of 20% at sandy clay loam texture. Sand was also predicted (R2= 0.86 and 0.72) in moisture content of 5 and 10% in clay loam texture.
Aliakbar Noroozi; Ziaoddin Shoaei
Abstract
Wind erosion is one of the important processes of desertification in arid and semi-arid regions. This process causes destruction in the land, soil and water resources and etc. Dust phenomenon is one of the major consequences of wind erosion in the world and Iran, particularly in the west and south west ...
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Wind erosion is one of the important processes of desertification in arid and semi-arid regions. This process causes destruction in the land, soil and water resources and etc. Dust phenomenon is one of the major consequences of wind erosion in the world and Iran, particularly in the west and south west of the country. Therefore, the present study aimed to identify areas of dust generation potential in the Khozestan, Iran using the combination of statistical methods, remote sensing and modeling. The statistical results showed that the most frequent occurrence of this phenomenon happened between 2008 and 2009. Most dust events happened in the seasonal scale, late spring and early summer and in the monthly scale, happened in May, June and July. Dust detection on satellite images and study their concentration using indicators AOD and BTD represents the greatest concentration of dust in the west and south west regions of the Khuzestan province, since 80 percent of these dust occurred in these zones. Tracking of dust showed that during the warm period, most dust happened from north west-south east and west-east and during the cold period, especially at the end of period, the northern-southern dust affected the province. The assessment of land use change showed the reduction in the irrigated areas, vegetation and arid lands increased in 2015, especially for the half of area of western Khuzestan. These features and physiographic features such as erodible formations, saline soils and marshy, low soil moisture and high changes in land use, indicates the presence of dust prone areas and potential for west and southern province.
Ghazaale Madadi; Saeed Hamzeh; Aliakbar Noroozi
Abstract
Most of drought assessment systems are largely based on rainfall data. Although the short period of data, poor quality of rainfall measurement network and low-dense distribution of stations reduce the ability of detecting drought spatial patterns. Therefore, it is obligatory to detect climate data sources, ...
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Most of drought assessment systems are largely based on rainfall data. Although the short period of data, poor quality of rainfall measurement network and low-dense distribution of stations reduce the ability of detecting drought spatial patterns. Therefore, it is obligatory to detect climate data sources, which would get rid of this problem, then to be used as an alternative option. Accordingly, in this study for monitoring drought in West Frontier Basin (including the Ilam, Kermanshah, Kurdistan and Lorestan provinces), using meteorological data (including 30 climatology and synoptic stations), to assess monthly data satellite TRMM (3B43). Drought indicators using SPI index for time scales of three, six, nine and 12 months in the period of 12 years (2000-2012) were calculated. After evaluating the accuracy and validating of monthly data from satellite images, estimation value of the drought on the determined time scales was done by use of TRMM dataset. The estimated value of the drought (SPI) across the study area using TRMM satellite images and maps of rainfall of ground-stations was calculated in MATLAB software after that for all the pixels continuously SPI value was calculated. The results indicate that, the SPI index from satellite images and ground stations are closely related. According to the statistics of weather and precipitation, year 2008 was introduced as the low rainfall year, besides the results of the study showed that the SPI value of the basin, in 2008 was lowest that determined it as the dry year.
Sina Mallah Nokandeh; Mehdi Homaee; Aliakbar Noroozi
Abstract
Soil Organic Matter (SOM) is one of the most vital components in soil solid phase and plays an important role in soil aggregation. SOM considerably improves soil physical conditions during long time. Moreover, knowing the SOM content of arid and semi-arid areas could significantly affect the soil management ...
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Soil Organic Matter (SOM) is one of the most vital components in soil solid phase and plays an important role in soil aggregation. SOM considerably improves soil physical conditions during long time. Moreover, knowing the SOM content of arid and semi-arid areas could significantly affect the soil management in such SOM-lacking regions. The objective of this research was to compare four common statistical models with the purpose of acheiving the best model for estimating the SOM in Ivanekey and test the obtained model in another semi-arid area of Urmia plain. Two Hyperion images were collected for Ivanekey and Urmia plain which were used to identify the relationship between spectral bands and SOM by applying SWR, MinR, PLSR and PCA models. Models were calibrated by Ivanekey Hyperion images and verified by nine Ivanekey and 23 Urmia random samples. Results indicated that MinR and PCA models do not have reasonable accuracy, but SWR and PLSR can provide the highest accuracy with the same RMSE value of 0.18, and R2 of 0.69 and 0.66, respectively. It is also demonstrated that there is a close relation between SOM and Red and Short Wave Infra Red spectral regions.
Akbar Hassani; Hosseinali Bahrami; Aliakbar Noroozi; Shahin Oustan
Abstract
Reflectance spectroscopy can be used to study agricultural and environmental aspect of soil that are sensitive to soil organic and inorganic compounds. Despite the extensive studies in the field of visible-near infrared reflectance spectroscopy, there are rare researches in gypseous and calcareous soils. ...
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Reflectance spectroscopy can be used to study agricultural and environmental aspect of soil that are sensitive to soil organic and inorganic compounds. Despite the extensive studies in the field of visible-near infrared reflectance spectroscopy, there are rare researches in gypseous and calcareous soils. The objective of this study was to obtain a model that can predict chemical properties of gypseous soils via reflectance spectroscopy methods. Soil samples were collected from 102 locations in five different provinces in 0-30 cm of depth. Some chemical properties of soils, such amount of gypsum, equivalent calcite, cation exchange capacity, pH, EC, exchangeable calcium, magnesium, sodium and potassium and amount of silt, clay and sand were measured by standard methods in the laboratory. Air-dried soil samples were scanned at one nm resolution from 350 to 2500 nm, and calibrations between properties and reflectance spectra were developed using cross-validation under Partial Least Squares Regression (PLSR) and Boosted Regression Trees (BRT). Raw reflectance and first derivative reflectance data were used separately and combined for all samples in the data set. Data were additionally divided into two random subsets of 70 and 30 percent of the full data, which were each used for calibration and validation. Strongest correlations were obtained with gypsum, equivalent calcium carbonate, cation exchange capacity, exchangeable Ca and Mg, organic matter, sand and clay contents. Overall, BRT provided better predictions when under cross-validation. However, PLSR and BRT results were comparable in terms of prediction accuracy when using separate data sets for calibration and validation. In conclusion, VNIR spectroscopy was variably successful in estimating soil properties and showed its potential for substituting laboratory analyses or providing inexpensive co-variable data in environmental studies.
Maral Khodadadi; Mohammad Sadegh Askari; Fereydoon Sarmadian; Hossein Gholi Refahi; Ali Akbar Norouzi; Ahmad Heidari; Hamid Reza Matinfar
Volume 1, Issue 2 , July 2009, , Pages 99-110
Abstract
Salinity is the major factors of soil degradation in semi arid and arid regions. The main aim of this study was to evaluate the capability of Landsat ETM+ data for soil Salinity mapping in the selected part of the Qazvin plain, an area of arid environment. In this study spectral classes carried out on ...
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Salinity is the major factors of soil degradation in semi arid and arid regions. The main aim of this study was to evaluate the capability of Landsat ETM+ data for soil Salinity mapping in the selected part of the Qazvin plain, an area of arid environment. In this study spectral classes carried out on remotely sensed data and with the help of field observation and soil analysis were regrouped to soil salinity classes to prepare soil salinity map.. Soil sampling was implemented using stratified random sampling method, depending on landscape complexity and homogeneity as well as on the representativeness of Landsat ETM+ data. Also in each soil map unit at least one profile was studied for subsoil salinity variations. Field samples taken by using augur and profiles were analyzed in laboratory for Na+ , Ca2+ , Mg2+ cations, as well as soil texture, ECe and pH. We have analyzed the effectiveness of additional data such as digital elevation model to improve the accuracy of classification. Also NDVI, SRVI, PVI, SAVI, SI, BI and NDSI indices, PCA and Tasseled cap were analyzed. Soil salinity map of each selected bands produced and with ground truth map crossed. The results indicated that combination of DEM with ETM+ bands has highest accuracy. This study addressed that thermal band of ETM+ can increase the classification accuracy which illustrated its effective role to classify the soil salinity. Tasseled cap and other indices had almost high accuracy among studied image processing techniques. The SI and BI indices had the highest correlation with EC and could distinguish the saline and non saline soils while the optimum index factor had overall low accuracy.
