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Mapping of dust source susceptibility by remote sensing and machine learning techniques (case study: Iran-Iraq border).
2023
Pourhashemi, Sima | Asadi, Mohammad Ali Zangane | Boroughani, Mahdi | Azadi, Hossein
peer reviewed | A dust storm is a major environmental problem affecting many arid regions worldwide. The novel contribution of this study is combining indicators extracted from RS- and statistic-based predictive models to spatial mapping of land susceptibility to dust emissions in a very important dust source area in the borders of Iran and Iraq (Khuzestan province in Iran and Al-Basrah and Maysan provinces in Iraq). In this research, remote sensing (RS) techniques and machine learning techniques, including multivariate adaptive regression spline (MARS), random forest (RF), and logistic regression (LR), were used for dust source identification and susceptibility map preparation. To this end, 152 DSA for the period of 2005-2020 were identified in the study area. Of these DSA data, 70% was assigned to the Dust Source Susceptibility Mapping (DSSM) (training dataset) and 30% to model validation. Consequently, six factors (i.e., soil, lithology, slope, normalized vegetation differential index (NDVI), geomorphology, and land use units) were prepared as DSA's independent and effective variables. The results of all three models indicated that land use had the most impact on DSA. The validation results of these models using the test data showed sub-curves of 0.92, 0.86, and 0.76 for the RF, MARS, and LR models, respectively. Also, results showed that the RF model outperformed MARS (AUC = 0.89) and LR (AUC = 0.78) methods. In all three models, high and very high susceptibility classes generally covered a large percentage of the case study. The highest percentage of dust source points was also in this susceptibility category. Overall, the results of this study can be useful for planners and managers to control and reduce the risk of negative dust consequences.
Mostrar más [+] Menos [-]Living near an active U.S. military base in Iraq is associated with significantly higher hair thorium and increased likelihood of congenital anomalies in infants and children
2020
Savabieasfahani, M. | Basher Ahamadani, F. | Mahdavi Damghani, A.
In Iraq, war contamination is the result of dispensed bombs, bullets, detonation of chemical and conventional weapons, and burn-pit emissions by US bases. Increases in congenital anomalies were reported from Iraqi cities post-2003. These cities were heavily bombed and encircled by US bases with burn-pits. Thorium is a radioactive compound and a direct depleted-uranium decay-product. Radioactive materials, including depleted uranium, are routinely stored in US bases and they have been shown to leak into the environment. We conducted a case-control study to investigate associations of residential proximity to Tallil Air Base, a US military base near Nasiriyah, as well as levels of uranium and thorium in hair and deciduous teeth with congenital anomalies. The study was based on a sample of 19 cases and 10 controls who were recruited during late Summer and early Fall of 2016. We developed mixed effects logistic regression models with village as the random effect, congenital anomaly as the outcome and distance to the US base and hair metal levels (one at a time) as the predictor variable, controlling for child's age, sex and paternal education. We also explored the mediation of the association between proximity to the base and congenital anomalies by hair metal levels. We found an inverse association between distance to Tallil Air Base and risk of congenital anomalies and hair levels of thorium and uranium. The results of our mediation analyses were less conclusive. Larger studies are necessary to understand the scope of war contamination and its impact on congenital anomalies in Iraq.
Mostrar más [+] Menos [-]Spatiotemporal evolution of the remotely sensed global continental PM2.5 concentration from 2000-2014 based on Bayesian statistics
2018
Li, Junming | Wang, Nannan | Wang, Jinfeng | Li, Honglin
PM2.5 pollution is threatening human health and quality of life, especially in some densely populated regions of Asia and Africa. This paper used remotely sensed annual mean PM2.5 concentrations to explore the spatiotemporal evolution of global continental PM2.5 pollution from 2000 to 2014. The work employed an improved Bayesian space-time hierarchy model combined with a multiscale homogeneous subdivision method. The statistical results quantitatively demonstrated a ‘high-value increasing and low-value decreasing’ trend. Areas with annual PM2.5 concentrations of more than 70μg/m3 and less than 10μg/m3 expanded, while areas with of an annual PM2.5 concentrations of 10–25μg/m3 shrank. The most heavily PM2.5-polluted areas were located in northwest Africa, where the PM2.5 pollution level was 12.0 times higher than the average global continental level; parts of China represented the second most PM2.5-polluted areas, followed by northern India and Saudi Arabia and Iraq in the Middle East region. Nearly all (96.50%) of the highly PM2.5-polluted area (hot spots) had an increasing local trend, while 68.98% of the lightly PM2.5-polluted areas (cold spots) had a decreasing local trend. In contrast, 22.82% of the cold spot areas exhibited an increasing local trend. Moreover, the spatiotemporal variation in the health risk from exposure to PM2.5 over the global continents was also investigated. Four areas, India, eastern and southern China, western Africa and central Europe, had high health risks from PM2.5 exposure. Northern India, northeastern Pakistan, and mid-eastern China had not only the highest risk but also a significant increasing trend; the areas of high PM2.5 pollution risk are thus expanding, and the number of affected people is increasing. Northern and central Africa, the Arabian Peninsula, the Middle East, western Russia and central Europe also exhibited increasing PM2.5 pollution health risks.
Mostrar más [+] Menos [-]Asymmetry in the otolith length and width of three sparid fish species collected from Iraqi waters
2020
Abdulsamad, Saad M.S. | Jawad, Laith A. | Al-Nusear, Azal N.B. | Waryani, Baradi | Rutkayová, Jitka
Bilateral asymmetry is presumed to reveal the developmental variability of the fish in polluted aquatic environments. In these habitats, high-level asymmetry develops, and these fish expend more energy to balance their growth than fish that are not under an impact. A total of 210 specimens of Acanthopagrus bifasciatus, A. latus and Sparidentex hasta were collected from the marine waters of Iraq in the northwest part of the Arabian Gulf. The asymmetry was calculated for the sagittal otolith characters of length and width. Otolith width has lower asymmetry than otolith length for the three sparid fish species investigated. An increase in the value of fluctuating asymmetry with fish length was observed. This could be a pertinent indicator of pollution in the habitat.
Mostrar más [+] Menos [-]Morphological asymmetry in the greater lizardfish Saurida tumbil (Bloch, 1795) collected from the marine waters of Iraq
2020
Jawad, Laith A. | Abed, Jassim M.
Asymmetrical variations in six bilateral morphological characters of 75 specimens of Saurida tumbil obtained from the marine waters of Iraq were assessed. The level of asymmetry in the snout length was highest among the morphological traits examined. Variations in asymmetry in S. tumbil increased with size. These variations are possibly due to chemical contaminants.
Mostrar más [+] Menos [-]World record extreme sea surface temperatures in the northwestern Arabian/Persian Gulf verified by in situ measurements
2020
The Arabian or Persian Gulf is recognized as one of the warmest estuaries globally. The sea surface temperature (SST) has been utilized in several studies to gauge the global warming associated with climate change. In the current investigation we present detailed in situ SST measurements for five consecutive years (2016, 2017, 2018, 2019, 2020) in the northwest of the Gulf, specifically in Kuwait Bay. Results of data analyses were compared with the historical records for the region, revealing that the SST reached an extreme level never previously recorded either in the Gulf. The extreme SST in Kuwait Bay reached 37.6 °C, recorded by the offshore station KISR01 located in the middle of the Bay. The event was associated with heatwave, neap tides, and an extended period of Kous winds which are characterized by high humidity levels and accompanied by large-scale intermittent fish kill incidents that extended the full length of the Kuwait coastline. Several fish kill incidents were reported also at the northern edge of the Gulf along Shatt Al Arab stretch in Iraq. The species found dead during the incident varied considerably, unlike those found in the frequent summer incidents. The records presented in this study may provide evidence to the effects of global warming, aid further research, and encourage the concerned international government bodies to deliver urgent environmental policies.
Mostrar más [+] Menos [-]Improving of global solar radiation forecast by comparing other meteorological parameter models with sunshine duration models
2022
Uçkan, İrfan | Khudhur, Kameran Mohammed
The aim of this study is to compare sunshine duration-based models and the other meteorological parameter-based models and to develop new forecasting models. The estimation and comparison of global solar radiation has been made by using twenty-four empirical models including three new models for different location named Arbil, Dohuk, and Sulaimania of Northern Iraq. The reason of using these different locations is to test the accuracy of the other meteorological parameter models by comparing the sunshine duration models for different region. Mostly common statistical error values are used to evaluate the performance of the estimation models and to identify the models that will give the closest results to the actual values. According to the results, it was seen that the models based on other meteorological parameters have better predictions than the models based on the sunshine duration. While the R² value of the best models depending on the sunshine duration ranged from 0.97 to 0.99, the R² values of the best models of other meteorological parameters are above 0.99. Furthermore, it is observed that the new proposed models provide better estimates of global solar radiation at different locations than all models used in this study.
Mostrar más [+] Menos [-]Classification Maps for TDS Concentrations in the GIS Along Euphrates River, Iraq
2021
Chabuk, Ali | Hammood, Zahraa Ali | Anṣārī, Naẓīr | Abed, Salwan Ali | Laue, Jan
Iraq currently undergoing the problem of water shortage, although Iraq has two Rivers (Euphrates and Tigris) pass throughout most of its areas, and they have represented a major source of water supply. In the current research, to evaluate the quality of the Euphrates river in Iraq based on the values of total dissolved salts (TDS), the TDS concentrations were collected from sixteen sections along the river in the three succeeding years (2011, 2012, and 2013). The evaluation of the river was done depending on the classification of (W.H.O. (World Health Organization). (2003). Total Dissolved Salts in Drinking-water: Background document for development of W.H.O. Guidelines for Drinking-water Quality. World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland). of rivers for drinking uses. Inverse Distance Weighting Technique (IDWT) as a tool in the GIS was employed to establish the maps of the river that using interpolation/prediction for the TDS concentrations to each selected year and the average values of TDS for these 3 years. Based on the five categories of rivers’ classification of the TDS concentrations according to the (W.H.O. (World Health Organization). (2003). Total Dissolved Salts in Drinking-water: Background document for development of W.H.O. Guidelines for Drinking-water Quality. World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland), the Euphrates river was classified, and the maps of classification for the years 2011, 2012 and 2013 and the average values for 3 years were created. The average values for 3 years of TDS along the Euphrates river indicated that the sections from SC-1 to SC-4 as moderate-water-quality-Category-3, the sections from SC-5 to SC-10 as poor-water-quality-Category-4, while the sections between SC-11 to SC-16 as very poor-water-quality-Category-5. The interpolation maps showed that the Euphrates river in Iraq was ranged from moderate water quality (Category-3) to very poor water quality (Category-5).
Mostrar más [+] Menos [-]Uranium Concentrations and Some Physicochemical Parameters of Water Samples at Marshes (Ahwar) in Dhi-Qar Governorate
2021
Marzaali, Awsam Abdulsattar | Al-Shareefi, Mohammed A. | Abojassim, Ali Abid
The solid-state nuclear track detector techniques were used in this study to measure the level of uranium isotopes (²³⁸U, ²³⁵U, and ²³⁴U) that were found in water samples collected from marshes (Ahwar) at Dhi-Qar governorate, southern Iraq. The apparatus used for this study purposes was TASTRAK CR-39 plastic. In this study, we measured the following risk factors: the radiological risk, annual effective dose (ET) of uranium isotopes, the excess cancer risks, the chemical toxicity risk, lifetime average daily dose (LADD), and hazard quotient (HQ). Using different techniques, the water samples were analyzed for other physicochemical properties such as hydrogen ion concentration (PH), electrical conductivity (EC), and total dissolved solids (TDS). This study has proved that uranium isotopes were found in different concentrations in all water samples that were taken from different places of marshes. The concentrations of uranium isotopes in the collected samples were ranging from 0.87±0.072 to 1.89±0.093 μg/L, with an average value of 1.23±0.05 μg/L. The average values (with SE in Bq/L units) for ²³⁸U, ²³⁵U, and ²³⁴U were 1.51±0.06, 0.07±0.002, and 1.53±0.06, respectively, while the average values of ET, LADD, and HQ were 0.107±0.004 mSv/year, (0.326±0.013) × 10⁻³, 0.040±0.001 μg/kg.day, and 0.066±0.002, respectively. In addition to the previous results, the study has showed that the average value of PH, EC, and TDS with the SE were 7.84±0.22, 3999.95±294.45 μS/cm, and 2601.35±197.77 mg/L, respectively. The results revealed that the concentrations of uranium isotopes in the studied samples were below the instrumental detection limit (1.9 μg/L). Comparing the results of radiological risk and chemical toxicity risk of this study with those published by global organization and universal researches, it was found that these concentrations were within the allowed limits permissible to human consumption and domestic use. Besides these results, the values of EC and TDS were higher than the permissible limits of Iraqi and international standards for irrigation purposes. For all the aforementioned, it might be concluded that there are no health risks to humans by drinking the water of the marshes of Dhi-Qar Governorate according to uranium levels, but cannot be assumed to be of good quality.
Mostrar más [+] Menos [-]The Interactive Impact of Land Cover and DEM Resolution on the Accuracy of Computed Streamflow Using the SWAT Model
2020
Al-Khafaji, Mahmoud | Saeed, Fouad H. | Anṣārī, Naẓīr
Twenty daily time step–based SWAT simulation models for the Duhok, Adhaim and Dokan dam watersheds, in Iraq, were implemented using five land cover (LC) and digital elevation model (DEM) of different resolutions. The optimal LC and DEM for computing the most accurate streamflow for each watershed were specified. Results indicated that delineation of the flat watersheds is significantly affected by the DEM resolution and there was no evident trend on the computation of watersheds’ total areas, boundaries, number of subbasins and stream networks. Moreover, there is no significant trend between the increase in LC and DEM resolutions and accuracy of the computed streamflow. The most accurate streamflows for the Duhok, Adhaim and Dokan watersheds were computed using LC (DEM) of 30 m, 1000 m and 1000 m.
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