فهرست مطالب

محیط شناسی - سال چهل و هشتم شماره 2 (پیاپی 102، تابستان 1401)

فصلنامه محیط شناسی
سال چهل و هشتم شماره 2 (پیاپی 102، تابستان 1401)

  • تاریخ انتشار: 1401/06/02
  • تعداد عناوین: 6
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  • شهریار فضلی، سمیه سیما*، علی جعفر موسیوند صفحات 125-152

    در دو دهه اخیر، رخدادهای متناوب شکوفایی جلبکی در آب های جنوبی ایران و به خصوص تنگه هرمز خسارات اقتصادی و زیست محیطی قابل توجهی به بار آورده است. این پژوهش با هدف شناسایی مدل های سنجش از دوری و عددی مناسب برای پایش شکوفایی جلبکی و متغیرهای محیطی موثر و تحلیل الگوی مکانی-زمانی شکوفایی جلبکی طی سال های 2019-2003 انجام شد. به این منظور غلظت کلروفیل در مقادیر بالا به عنوان متغیر اصلی نشان دهنده شکوفایی جلبکی انتخاب شد و ارتباط آن با متغیرهای محیطی شامل دمای سطح آب، شوری، عمق اپتیکی ذرات معلق و سرعت باد مورد بررسی قرار گرفت. نتایج نشان داد که دما و شوری به ترتیب مهم ترین متغیرهای موثر هستند و محدوده دما و شوری مطلوب برای رشد جلبک ها در منطقه به ترتیب 27-22 درجه سانتی گراد و psu 39- 5/37 می باشد. همچنین در بازه زمانی بین ماه های نوامبر تا فوریه بیشترین احتمال رخداد شکوفایی جلبکی وجود دارد. مناطق شمالی و مرکزی تنگه هرمز نیز نسبت به سایر مناطق بیشتر تحت تاثیر شکوفایی جلبکی قرارگرفته اند. نتایج این مطالعه با کمک به توسعه مدل های هشدار زودهنگام شکوفایی جلبکی می تواند در پیشگیری و کنترل خسارات ناشی از آن در منطقه نقش مهمی ایفا کند.

    کلیدواژگان: کلروفیل، داده های سنجش ازدور، دمای سطح آب، شوری، تحلیل همبستگی
  • محمدرضا امیری فهلیانی*، احمد رضایی، مقدسه ریاحی صفحات 153-178

    محیط نقش مهمی در پویایی بیماری و تعیین سلامت افراد دارد. به طور خاص، محیط ساخته شده تاثیر زیادی در مهار هر دو بیماری مزمن و واگیردار در انسان ها دارد. پژوهش حاضر از نظر هدف کاربردی، از حیث روش پیمایشی در سطح اکتشافی و مبتنی بر رویکرد آینده پژوهی صورت گرفته است. مطالعه حاضر با عملیاتی-کردن چارچوب ساختار فضایی و کارکردی شهرها، یک رویکرد جامع تر برای بهینه سازی برنامه های مهار و سیاست های کاهش بیماری های واگیردار با استفاده از شاخص های موثر در ساختار و کارکرد شهری با رویکرد آینده پژوهی ارایه می دهد. نیروهای پیشران با روش دلفی مشخص، و سپس این عوامل براساس میزان اهمیت و عدم قطعیت، اولویت بندی و حیاتی ترین عوامل مشخص، و برای نوشتن سناریوهای محتمل از نرم افزار (Micmac) استفاده شده است. در مرحله سناریوپردازی، تعداد 45 متتغیر کلی شناسایی شدند. با توجه به یافته های پژوهش از بین این عوامل شاخص بافت فرسوده و تراکم جعیت، ضعف مدیریت شهری، موقعیت اقتصادی، توزیع نامناسب خدمات شهری تاثیرگذارترین عوامل کلیدی ساختار فضایی و کارکردی این کلانشهر در مواجهه با بیماری های واگیردار می باشد همچنین ضعف فعالیت بدنی در رتبه های بعدی و دارای بیشترین اثرگذاری مستقیم و همچنین کیفیت محیطی، و ضعف فعالیت بدنی دارای بیشترین میزان اثرپذیری مستقیم بر دیگر متغیرها بوده اند.

    کلیدواژگان: مطالعات آینده پژوهی، برنامه ریزی سناریو، ساختار فضایی و کارکردی کلانشهرها، بیماری های واگیردار، کلانشهر اهواز
  • سیده زینب یعقوبی، سید عباس حسینی*، غلامرضا نبی بیدهندی، احمد شرافتی صفحات 179-196

    با گسترش روزافزون شهرنشینی و آلودگی ناشی از آن، جامعه بشری را با عوارض و مسایل زیست محیطی گوناگونی مواجه ساخته است. از این مسایل، مشکلات مرتبط با خاک اهمیت ویژه ای دارد. از این رو خاک، شاخص مهمی برای در معرض قرارگیری انسان به فلزات کمیاب در محیط های شهری است. فلزات سنگین موجود در پارک های شهری یکی از مهمترین شاخص های منعکس کننده وضعیت آلودگی در محیط زیست شهری هستند. در این مطالعه غلظت فلزات سنگین در خاک تعدادی از پارک های منتخب شهر تهران مورد ارزیابی قرار گرفت. پس از نمونه گیری و آماده سازی نمونه ها، غلظت فلزات سنگین در آن ها اندازه گیری و با استفاده از شاخص های موجود میزان ریسک اکولوژیکی و غنی شدگی فلزات سنگین با بهره گیری از تحلیل های آماری مختلف مورد ارزیابی ریسک قرار گرفت. نتایج شاخص غنی سازی، غنی شدگی قابل توجه سرب، روی و کادمیم را بر اثر فعالیت های انسانی نشان می دهد. در محاسبات ریسک اکولوژیکی نیز، سرب و کادمیم ریسک قابل توجه و بالایی دارند و جالب توجه است که تمامی مناطق نمونه گیری ریسک اکولوژیکی خیلی زیادی دارند. در انتها با توجه به تحلیل های آماری، شباهت رفتاری آلاینده ها و مطالعات پیشین، تردد وسایل نقلیه به عنوان اصلی ترین منبع انتشار فلزات سنگین در خاک های مربوط به پارک های تهران معرفی گردید.

    کلیدواژگان: فلزات سنگین، ریسک اکولوژیک، کلان شهر تهران، غنی شدگی
  • رضا مدرس، احمد نوحه گر* صفحات 197-220

    در پژوهش حاضر به منظور بررسی آلودگی هوای منطقه ویژه اقتصادی خلیج فارس در غرب بندرعباس، نخست وارونگی های دمایی اتفاق افتاده طی سال های 2010 تا 2020 با استفاده از داده های رادیو سوند استخراج گردید. سپس با استفاده از مدل ایرمود غلظت ذرات معلق (PM2.5 - 10)، گازهای دی اکسیدگوگرد، مونوکسیدکربن و ازن خروجی از 60 دودکش برای روزهای وارونگی در شعاع 20کیلومتری پیش بینی شد. نتایج نشان داد بیشترین وارونگی در دی و بهمن به ترتیب با 28 و 26 روز در ماه و کمترین وارونگی با 11 و 13 روز در مرداد و تیر بود. کمترین ارتفاع پایه لایه وارونگی نیز مربوط به دی و بهمن به ترتیب با 10 و 13 متر و بیشترین ارتفاع با 408 متر در شهریور بود. میانگین سالانه وارونگی ها 8/250 روز در سال بوده که 4/157 مورد از نوع تابشی و 4/93 مورد فرونشینی بوده است. مدل ایرمود نشان داد غلظت ذرات معلق (PM2.5)، دی اکسیدگوگرد و ازن بیشتر از استاندارد بود، اما ذرات معلق (PM10) و مونوکسیدکربن کمتر از حد استاندارد بود. بادهای جنوب شرقی مهم ترین پارامتر در پراکنش آلاینده ها بوده که باعث شده ستون دود بادبزنی به سمت شمال غربی انتقال یابد. پیش بینی پراکنش آلاینده ها می تواند در تدوین مدیریت راهبردی در حفاظت محیط زیست و توسعه پایدار مفید واقع گردد.

    کلیدواژگان: اینورژن، ستون دود، ذرات معلق، مدل ایرمود، ناحیه صنعتی
  • امیرحسین منتظری، مهدی مظاهری*، سعید مرید صفحات 221-248

    بخشی از مشکلات در جهان که مانعی در برابر توسعه اقتصادی و کشاورزی می باشد، افزایش شوری آب و خاک است. اروندرود که از مهم ترین رودخانه های مرزی کشور است در اثر نفوذ آب شور خلیج فارس با کاهش چشمگیر کیفیت آب و خاک اراضی مواجه است که تهدید جدی برای منطقه محسوب می شود. اروندرود از تقاطع رود های دجله و فرات تشکیل می شود و درنهایت به خلیج فارس می ریزد. در تحقیق حاضر نتایج شبیه سازی مشخص کرد که در شرایط متوسط جریان ورودی اروند، جبهه ی آب شور تا 60 کیلومتر از پایین دست به رودخانه نفوذ می کند و کیفیت آب اروندرود را تحت تاثیر قرار می دهد. سپس اثر شوری آب رودخانه بر شوری خاک از دو جنبه، شوری خاک توسط نفوذ مستقیم از جداره های رودخانه و شوری خاک توسط استفاده بلندمدت از آب رودخانه به منظور آبیاری اراضی صورت گرفت. نتایج نشان داد در 188 کیلومتری از بالادست رودخانه تا 242 متر آب شور بر خاک دو طرف اروندرود اثرگذار است و در جنوب شهر آبادان این باند شوری از بین می رود. پیش بینی شوری اراضی توسط آبیاری با آب رودخانه در شرایط ماندگار، نشان داد شوری متوسط عصاره اشباع خاک در ایران در منطقه ای به نام الگصبه و در عراق جنوب منطقه فاو شوری خاک به 97/3 ppt می رسد.

    کلیدواژگان: رودخانه اروند، کیفیت آب رودخانه، نفوذ جبه ی شوری، شبیه سازی عددی، شوری خاک
  • محمدحسن پنجه شاهی، نسیم طاهونی* صفحات 249-278

    هدف تحقیق حاضر، شناسایی منابع تولید گازهای گلخانه ‏ای فلویوردار، تهیه موجودی اولیه انتشار و ارزیابی ظرفیت‏های موردنیاز برای احصاء این گازها در فهرست موجودی گازهای گلخانه ‏ای کشور به منظور برنامه ‏ریزی اقدامات تغییر اقلیم در ایران ذیل پروژه پایداری اقلیم سازمان ملل متحد می‏باشد. مرحله اول شناسایی منابع اصلی انتشار آلاینده‏ ها توسط گازهای گلخان ه‏ای مذکور و جمع ‏آوری اطلاعات لازم و مرحله دوم تخمین میزان تولید و مصرف این گازها در کشور است. بر حسب اینکه چه نوع اطلاعاتی اعم از واردات، میزان تولید و مصرف این گازها و یا اطلاعات فروش دستگاه‏های تولیدکننده این گازها به صورت جداگانه در اختیار باشد، از یکی از روش‏های سطح یک یا سطح دو برای محاسبه میزان انتشار استفاده شده است. مقدار انتشار این گازها در سال 2019، 3/62 میلیون تن معادل دی ‏اکسیدکربن برای گازهای هیدروفلویورکربن‏، 180 گیگاگرم معادل دی ‏اکسیدکربن برای گاز هگزا فلوراید گوگرد و 1130 گیگاگرم معادل دی ‏اکسیدکربن برای گازهای پرفلویورکربن‏ براورد شد. تخمین میزان انتشار گاز تری فلویورید نیتروژن با اطلاعات موجود امکان‏پذیر نبود. در مرحله آخر راهکارهایی برای کاهش انتشار این گازها ارایه شده تا در سیاست‏های توسعه ‏ای کشور در تغییر انتشارات در آینده لحاظ شود. دستاورد اصلی این تحقیق توانمندسازی کشور برای احصاء این گازهای جدید گلخانه ‏ای می‏باشد.

    کلیدواژگان: انتشار گازهای گلخانه ‏ای فلوئوردار، هیدروفلوئورکربن‏ها، هگزا فلوراید گوگرد، پرفلوئورکربن‏ها، تری فلوئورید نیتروژن
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  • Shahryar Fazli, Somayeh Sima *, Ali Jafar Mousivand Pages 125-152
    Introduction

    In the past two decades, frequent Harmful Algae Bloom (HAB) events have occurred in the southern coast of Iran, particularly in the Strait of Hormuz. Because of the resultant environmental consequences and economic losses, it is of high importance to identify the key abiotic forces of HAB and their critical ranges to mitigate HABs. Studies of algal blooms in the Strait of Hormuz over the past two decades show that Noctiluca has been the dominant algae. Regional studies show that nutrient concentrations are generally higher in the region in autumn than in winter and in winter than spring. Moreover, in early autumn upwelling in the east of the Strait of Hormuz and along the coasts of Iran causes the enrichment of coastal waters with nutrients, especially nitrate. On the other hand, the density gradient reduction between the Persian Gulf and Sea of Oman during the cold months, along with the loss of summer stratification due to air cooling in the region, leads to the mixing of water and nutrients in depth.This study aims at 1) identifying the appropriate remote sensing-based algorithms and numerical models for monitoring HABs, 2) recognizing the key abiotic factors in the formation and expansion of HABs, and 3) understanding the spatiotemporal variation of long-lasting HABs and their effective abiotic factors from 2003 to 2019. The findings of this study can provide useful insights into the design of an early alarm system of HAB to prevent its negative environmental and economic consequences.

    Materials and Methods

    In this study, variations of abiotic variables affecting the formation of algal blooms in the Strait of Hormuz including sea surface temperature and salinity, aerosol optical thickness (AOT), and wind speed were analyzed during the three HABs between 2003 and 2019, having a duration of longer than two months. Concentration of Chlorophyll a has been considered as the main indicator of algal bloom. To detect algal blooms in many studies, different thresholds of chlorophyll concentrations from 2.5 to 25 mg/m3, for different levels of warning, have been mentioned in the Literature. Based on the field data and values obtained from satellite imageries at the time of algal bloom, a threshold of 5 mg/m3 for chlorophyll concentration was selected to determine the algal bloom event in the Strait of Hormuz.Then, the performance of several numerical and remote sensing-based models for monitoring algal bloom and the aforementioned abiotic factors were assessed using Field data acquired from oceanographic, fisheries, geological and meteorological organizations. Several evaluation criteria including Wilmot agreement index (d), mean bias error (MBE), root mean square error (RMSE), and correlation coefficient (R) were used for validation of the models.After selecting the best models for each variables, their monthly maps between 2003 and 2019 were extracted. Then, the lumped (mean values in the study area) and spatial (between maps) correlation analysis between chlorophyll-a concentration and the other abiotic variables were performed using Pearson correlation method at 95%. In addition, correlation analysis was performed without and with considering a one-month delay. Subsequently, the anomalies of these variables during the three algal bloom events were examined compared to their long-term mean monthly values. Likewise, spatial changes in the chlorophyll concentration were obtained from the selected model and the areas affected by algal bloom in the Strait of Hormuz were identified.

    Discussion of Results

    Based on the results of the performance indices, OC3M, OCSST, HYCOM and MERRA2 models were selected as the optimal models for monitoring chlorophyll, sea surface temperature, salinity, and wind speed, respectively.In the first period, September 2008, the algal bloom was formed in the southwestern regions of the Oman Sea and through the east-west currents moved toward the northern shores of the Strait of Hormuz. By January 2009, it expanded and reached its peak in the interior part of the Persian Gulf. The second event occurred in January 2012, just lasted about two months. The northern regions of the Strait, especially Qeshm Island as well as the coasts of Oman and the UAE were the most affected areas by algal blooms. In the third algae bloom episode, the upsurge in algal concentration has started from the coastal areas of Oman and the UAE and quickly reached the central and western parts of the Strait of Hormuz in January 2015 and then reached its peak in the following month, especially in the southern parts of the Strait of Hormuz and UAE. Regarding the long-term pattern of changes in chlorophyll concentration in the area (figure 1), it can be said that from 2006 to 2015, almost every three years, an algal bloom event lasting more than a month can be observed in the central areas of the strait. Also, in most of the years during the study period (except for the number of years 2001, 2002 and 2016), the mean chlorophyll concentration approached the threshold of algal bloom from November to January. Moreover, the eastern areas are more at risk of increasing chlorophyll concentration than the western. This could be due to lower temperatures, lower salinity and more available nutrient in the Oman Seas compared to the Persian Gulf. The temporal variation of sea temperature and salinity in the west and east part of the Strait of Hurmuz showed a slight increase in the peak values in the western regions compared to the eastern and central areas. AOT is almost the same in all the three regions, while wind speed follows an irregular trend in three areas. These changes are more evident in the western regions.Due to the variations in the monthly mean of chlorophyll throughout the years 2003-2019 in the region, the lowest chlorophyll occurs in summer and increases with the beginning of autumn and lastly reaches its maximum in winter and then decreases until spring. This circulation pattern is common among subtropical waters. According to correlation analysis, while chlorophyll level has a significant direct correlation with salinity, it inversely correlates with sea surface temperature. In general, with falling temperature in autumn and winter, chlorophyll concentration rises in the Strait of Hormuz. Wind speed, which intensifies dust and the movement of sea currents, has a weak inverse relationship with chlorophyll. This means that in summer, when the highest degree of dust occurs in the region, the chlorophyll is negligible, and as the weather cools, the amount of dust in the region decreases. This seasonal pattern is known for aerosols for desert areas, including the Middle East.

    Conclusions

    The key results of this research are:1- The optimum models for monitoring chlorophyll, sea surface temperature, salinity and wind speed in the Strait of Hormuz are OC3M, OCSST, HYCOM, and MERRA2 models, respectively.2- Algae blooms are more likely to occur in the Strait of Hormuz between November and February.3- The central and northern regions of the Strait of Hormuz are more prone to algal blooms than other regions due to more desired abiotic conditions for algae growth. Similarly, algal blooms are more likely to occur in the eastern than the western part of the Strait of Hormuz.4- According to the study of the three algae bloom episodes having a duration of more than two months, the desired temperature and salinity ranges for algae growth are 22-27 ° C and 37.5-39 psu, respectively. Concurrent occurrence of these abiotic conditions highly increases the risk of algal blooms in the Strait of Hormuz.The increased nutrient discharge from urban and industrial effluents together with a rise in water temperature and salinity due to the development of desalination plants will increase the risk of algal blooms in the southern coasts of Iran. Using the promising potential of satellite data (with an appropriate resolution) and valid algorithms, as shown in this study, can pave the way for developing develop regional early warning systems of algae bloom.

    Keywords: Chlorophyll, remote sensing data, surface temperature, salinity, Correlation analysis
  • Mohammad Reza Amiri Fahlyiani *, Ahmad Rezaee, Moghadase Riyahi Pages 153-178

    Future scenarios of the effects of the spatial and functional structure of Iran's metropolitan areas on the growth and prevalence of infectious diseases and COVID-19 (case study; Ahvaz metropolis)IntroductionThe health of individuals and populations is affected by the environment in which they live. Some environments harbour more pathogens than others and population densities vary across environment, which influences disease transmission dynamics. Moreover, variation in resource distribution across environments can determine movement patterns, which can expose individuals to new pathogens, but also contribute to their health by increasing activity. The built environment can be modified to promote healthy behaviours and reduce the risk of contracting a disease. The metropolis of Ahvaz, as the administrative-political center of Khuzestan province and the center of the southwestern region of the country with a population of 1.3 million people in 2016, has a special political and economic position so that this city is about One-fourth of the urban population of Khuzestan province. The population of the problematic areas of Ahvaz metropolitan area is about 340,000 people, which occupies approximately 4,500 hectares of the total area of the city (21%) . Existence of large industrial factories, administrative and industrial facilities, South Oilfields Company, National Iranian Drilling Company, Pipe Manufacturing, Carbon Black, Pipe Rolling, Axin Steel and Khuzestan Steel Ahvaz have become one of the most important industrial centers in Iran and this is why It has caused many immigrants to come to this city. For this reason, Ahvaz is facing an environmental pollution crisis, which has faced a significant and dangerous increase in pollution in the last decade, and in 2013, Ahvaz was named the most polluted city in the world in the international media. In this article, we will discuss the future effects of the environment on chronic and infectious diseases in Iran's metropolises by case study of Ahvaz metropolis. And our goal is to review the indicators in the form of structural analysis that pave the way for further, deeper studies of each of these different cases that are rooted in the fabric of the structure and function of Iranian metropolises and, of course, part of the heart of these elements and determinants. Quality and vitality of the urban environment and a factor to improve the quality of the urban environment and consequently the physical and mental endurance of citizens in the face of infectious diseases and Quaid 19, which has been invading the cities of the world and Iran for some time. We have placed many human and social. With the future research approach, we identify the key factors and drivers and the effects of these key factors on the structure and function of Ahvaz metropolis when faced with infectious diseases and scenario building in this field. Finally, the main question of the present study is that what are the key factors affecting the future of the effects of the structure and function of Iranian metropolises on the case study of Ahvaz metropolis when faced with epidemic diseases and the future?Matherials & MethodsThis research is in terms of the type of applied-theoretical research and in terms of the nature of descriptive-analytical research, and the method of data collection is also library and field. Also, in terms of nature, it is based on new methods of future science, research, analysis and exploration that have been done using quantitative and qualitative models. In exploratory designs, a measurement tool is usually developed through qualitative research. For this purpose, by collecting and analyzing qualitative data, the main aspects of the phenomenon under study are determined. These aspects are considered as the desired dimensions for compiling data collection tools. The data of this study were collected through interviews with experts and then ranked by Delphi method. The criteria for selecting experts were theoretical mastery, willingness and ability to participate in research and access, which is described in the table below of the specifications of the experts referred to..Discussion of ResultsTherefore, this study aims to assess the awareness and attitude of experts on the effect of effective factors on the structure and spatial function of Iranian metropolises on exacerbating or weakening the effects of infectious diseases using structural analysis. In the framework of futuristic studies and using the scenario approach, while measuring the general situation of the structure and function of Ahvaz metropolis, its stability or instability pattern can also be seen from the spatial distribution of variables at the level of charts and outputs of Mic software. Mac received. Also, the almost high percentage of filling coefficient (83%) in the research variables confirms the validity and reliability of the research tools at an almost high level. For this purpose, the present study, while measuring the direct effects of variables, has also considered the dimensions of the impact and indirect and potential competence of variables in the spatial arrangement of variables and the development of key propulsion forces and final scenarios.Also, the analysis of the obtained information confirmed that the indicators of urban structure and function are unstable in the fight against infectious diseases in Ahvaz, so that the continuation of the current situation will lead to the formation of a catastrophic scenario, and in the best case, If the current situation continues, the key features of the metropolitan structure and function of this metropolis will intensify social harms, weaken social capital and consequently weak social trust, social participation, inability to adapt to harms ... will.Conclusions worn-out urban fabric, population density, lack of income, migration, urban management weakness, were identified as key factors in the structure and function of metropolitan environment in the spread of infectious diseases and barriers to healthy living in Ahvaz metropolis. All of these factors have negative health consequences for this population and may also prevent any intervention aimed at preventing and treating infectious diseases and covid 19. Increasing the level of communication and mobility of people in metropolitan areas will lead to a high risk of transmitting the disease. Therefore, the urban space and environment will be prone to the growth of infectious diseases, including Quaid 19, which includes all conditions, including inequality in access to urban services at the metropolitan level, distinct access to health services in urban areas, air pollution, poor public awareness, class distance. In this metropolis, there is a lack of facilities and infrastructure to increase the physical activity of citizens in this city, for the spread and spread of infectious diseases. Although urban poor areas are usually more affected, infections have the potential to spread rapidly to other parts of the city, including wealthy neighborhoods and tourist areas.The current situation of Ahvaz metropolis in the face of epidemic diseases will increase, as a result of which the situation in Ahvaz will become critical and will face crises, human, environmental, managerial, economic, social and institutional. . In this situation, the metropolis will face a fragile anomaly. And it becomes an inefficient metropolis in the face of sudden events and infectious diseases such as Quaid 19 disease. The emigration of a large number of people from the surrounding towns and villages to Ahvaz, on the one hand, and the lack of proper supervision over physical development, on the other, will lead to the development of the unbalanced expansion of Ahvaz and the formation of more marginalized areas and informal settlements throughout it. Urban inequalities and distinct access to urban services and health care have adverse effects on urban society. Unemployment and economic problems will lead to more social harm. The weakness of security will lead to the weakening of the mental and emotional endurance among the citizens. Infectious diseases disproportionately affect urban poverty. In addition, these diseases affect all areas of the metropolis regardless of the stages of economic development.

    Keywords: Future research, scenario planning, spatial, functional structure of metropolises, Infectious diseases, Ahvaz Metropolis
  • Seyedeh Zeinab Yaghoubi, Seyed Abbas Hosseini *, Gholam Reza Nabi Bidhendi, Ahmad Sharafati Pages 179-196

    The results of this study show that the ecological risk assessment index shows the low risk of most sampling areas, while the highest risk is related to the Shahr Park and Mellat Park, respectively. They also have a high ecological risk compared to other metals, cadmium and lead. The enrichment index also shows a significant accumulation of cadmium, lead and zinc and to some extent iron, chromium and nickel in soil samples of the study area due to human activities. Cadmium has the highest index of geochemical accumulation in surface soil samples of Tehran parks. Maximum cadmium levels were observed at stations in the Shahr Park, which are based on the classification of highly contaminated soils. Based on the results of statistical analysis and the enrichment coefficient of potential emission sources are identified as follows:Large amounts of copper, cadmium, lead and zinc enrichment coefficient indicate that human resources are the main source of these metals. Significant positive correlation and behavioral similarity of nickel and chromium with the mentioned metals show that nickel and chromium have the same emission sources with this group. Although these two metals have common sources with other metals, the low coefficients indicate that nickel and chromium may also have natural resources in relation to the surface soil samples of the sampling area.

    Keywords: Heavy metals, ecological risk, Tehran Metropolis, enrichment
  • Reza Modarres, Ahmad Nohegar * Pages 197-220

    In the present study, to investigate the air pollution of the Persian Gulf Special Economic Zone in the west of Bandar Abbas, at first inversions which occurred between 2010 and 2020 were extracted using radio sound. Next, using the AERMOD model, the concentration of PM2.5 - 10, SO2, CO and O3 emissions from 60 chimneys for inversion days in a radius of 20 km was predicted. The results showed that the highest inversion was in January and February with 28 and 26 days per month and the lowest with 11 and 13 days in August and July, respectively. The lowest base of the inversion layer was related to January and February with 10 and 13 m, respectively, and the highest with 408 m was in September. The average annual inversions were 250.8 days per year, which 157.4 were radiation and 93.4 were subsidence. The AERMOD model showed that the concentrations of PM2.5, SO2 and O3 were higher than standard, but PM10 and CO were lower than standard. Southeast winds are the most important parameter in the distribution of pollutants, which causes the smoke column move to the northwest. Predicting the distribution of pollutants can be useful in formulating strategic management in environmental protection and sustainable development.

    Keywords: inversion, Smoke column, suspended particles, AERMOD model, Industrial area
  • Amir Hossein Montazeri, Mehdi Mazaheri *, Saeed Morid Pages 221-248

    An increase in soil and water salinity is one of the world’s problems that are an obstacle to economic and agricultural development. The Arvand river (Shatt Al-Arab), one of the most critical border rivers, is facing a significant decrease in the quality of water and soil due to the intrusion of salty water from the Persian Gulf, which is considered a severe threat to the region. It is formed from the intersection of the Tigris and Euphrates rivers and finally flows into the Persian Gulf. In the current research, the simulation results determined that in the average inflow conditions of Arvand, the saline front penetrates the river up to 60 km from the downstream and affects the river’s water quality. Then the effect of river water salinity on soil salinity was done from two aspects, soil salinity by direct infiltration from riverbanks and soil salinity by long-term use of river water for irrigation. The results showed that in 188 km from the upstream of the river, up to 242 meters, saline water affects the soil on both sides of the river, and in the south of Abadan, this saline band disappears. The prediction of land salinity by irrigation with river water in steady conditions showed that the average salinity of saturated soil extract in Iran in Al-gasbah and in Iraq south of Faw region reaches 97.3 ppt.

    Keywords: Arvand River, river water quality, salinity intrusion, Numerical simulation, Soil Salinity
  • Hassan Panjeshahi, Nassim Tahouni * Pages 249-278

    This study aims to identify sources of fluorinated greenhouse gases and evaluate the capacity needs assessment for consideration of these gases in the national GHG inventory and climate action planning for the "Climate Promise" project. These GHGs have a shorter atmospheric lifetime compared to CO2 but a high global warming potential and can warm the earth faster compared to CO2. The first stage is to identify the main sources of emissions by the mentioned greenhouse gases and collect the necessary information. The second stage is to estimate the production and consumption of these gases in the country. Depending on the data, including import, production, and consumption of gases or sales information of the devices producing these gases, we can use the Tier1 or Tier2 method to calculate the amount of emissions. Greenhouse gas emissions in 2019 were estimated at 62.3 million tons of CO2 equivalent for HFC gases, 180 Gg of CO2 equivalent for SF6 gas, and 1,130 Gg of CO2 equivalent for PFC gases. There is no information to estimate the NF3 emissions. In the last stage, solutions to reduce emissions of these gases are listed to be implemented in national development policies. The main achievement of this research is empowering the government to count these new greenhouse gases.

    Keywords: Fluorinated greenhouse gas emissions, Hydrofluorocarbons (HFCs), Sulfur hexafluoride (SF6), Perfluorocarbons (PFCs), Nitrogen trifluoride (NF3)