نشریه علوم محیطی
سال بیست و یکم شماره 4 (پیاپی 82، زمستان 1402)

Flood is caused by a sudden increase in the water level of a river due to heavy rainfall, in which excess water flows out of the basin and the riverbed and enters adjacent areas, causing extensive damage to the region's ecosystems and infrastructure. In order to determine and implement a strategic plan in the direction of crisis management, understanding the mechanism and development of the flood phenomenon and the amount of subsequent runoff is a priority. In recent years, flood events have occurred in the catchment area of ​​the dry river of Shiraz; The most terrible flood event occurred on the 25th and 26th of March 2019 in the basin and caused severe economic, social and human damage to the people of the city. By recognizing the mechanisms and developing atmospheric patterns of flood generation, the first step can be taken in flood control; Also, by predicting the amount of runoff produced, how to deal with it can be identified. For this reason, in order to manage the environment of the dry river basin of Shiraz, the present study tries to approach flood management based on recognizing flood generating patterns and simulating the amount of runoff produced.

In order to study rainfall in the dry river of Shiraz, the daily rainfall was obtained from 12 rain gauge stations in the area in the period 2001 to 2019. The rainfalls were then sorted on an annual and monthly scale, and the rainfall was zoned using the Kriging algorithm in ArcGIS. Also, rainfalls of more than 40 mm were extracted from 12 rain gauge stations and were considered as flood events. For each rainfall station, the number of flood events was determined and flood events were zoned by the kriging algorithm in ArcGIS. Next, three events of flood on 16 February 2017, 26 March 2019 and 23 January 2020, when the average rainfall in the Shiraz watershed was 100 mm every three days, were selected and interacted with a synoptic approach. Atmospheric conditions and flood patterns were identified. Next, using the HEC-HMS hydrological model, the amount of rainfall to runoff conversion in each of the sub-basins in the Shiraz watershed was simulated.

The results showed that the maximum precipitation occurs in February and the minimum in July. The maximum annual rainfall is 627 mm in the mountainous areas of Qalat and Golestan and the minimum is 245 mm in Maharloo Lake. Synoptic results showed that the low altitude and cold-water trough at the level of 500 hPa in the eastern Mediterranean along with the dynamic low-pressure system in Iran caused surface air instability in Fars Province and by injecting moisture from the Persian Gulf to the massif. The weather has caused floods in Shiraz. The results of rainfall-runoff modeling showed that the highest runoff in Sadra and Qalat sub-basins were 5773 and 5076 thousand m3, respectively, and the maximum peak discharge in Sadra and Qalat was 666 and 389 m3/sec, respectively. It happened at 17:00. The highest volume of rainfall penetration in Qalat and Chenar Rahdar was 5423 and 2546 thousand m3, respectively, and the lowest level of penetration in the Quran Gate was 247 thousand m3, the main reason being the high density of residential-commercial use in this sub-basin.

Therefore, it is suggested that in order to manage the flood crisis in Shiraz, controlling runoff produced in northern sub-basins such as Qalat, Golestan and Sadra and increasing the level of permeability can be effective in controlling floods.

The effect of the urban environment on the atmospheric air and the boundary layer of urban areas appears mostly in the form of a temperature island. The urban heat island creates an artificial thermal environment due to the significant disturbance of energy, heat and radiative forcings, which have faced challenges for urban residents, water resources, urban infrastructure, atmospheric pollutants and social comfort. In addition, it aggravates the heat and has a negative effect on life expectancy. The purpose of this research is to analyze the spatial and process of urban heat islands of Iranian metropolises in the summer season.

In this research,, five big cities of Iran including Tehran, Mashhad, Isfahan, Shiraz and Karaj were selected. Then, Landsat 7 and 8 satellite images from 2003 to 2018 were used to recover the land surface temperature (LST) and for spatial analysis we used the Gates-Ord-J statistics. Finally, for trend analysis, the Mann-Kendall method was used.

The results showed that the average LST in the built-up areas within the city limits is higher than the average LST in the surrounding non-urban areas and even sometimes the city itself, and the strongest (SUHI) has occurred in areas such as the asphalt surfaces of airport runways, parking lots and roofs. The intensity (SHUI) in all metropolitan cities in the city center was not higher than other areas. The results of trend analysis using Kendall's method showed that the surface temperature of the earth is increasing in all the five cities of Iran except for Isfahan. Also, regarding the spatial distribution of the surface temperature in the five cities of Iran, it was found that there is an inverse relationship between the building density and the surface temperature.

The surface temperature of the earth was increasing in all studied cities. The slope of the trend was also higher than 1 degree Celsius for the major cities under study, and the intensity of the trend was higher in Karaj city than other major cities under study. The minimum slope of the earth surface temperature trend was calculated in Isfahan and the maximum slope was calculated in Karaj. In the next studies, it is suggested to study more cities in order to make better plans for the development of other cities.

In recent decades, along with the physical development of cities and population increase due to immigration, heat islands, which are mainly the result of human made activities, have gained significant importance. So, the reduction of vegetation cover, the high consumption of fossil fuels, the emission of greenhouse gases and the use of inappropriate materials in urban construction have created the microclimate of a heat island above the metropolis of the world. Finally, it causes an increase in the land surface temperature, atmospheric stability, persistence and stabilization of pollutants and an increase in respiratory diseases. Today, by using remote sensing methods and using digital satellite images, it is possible to examine the land surface temperature with high accuracy and in a short period using MODIS sensors and Terra satellite images. Therefore, the main objective of the current research was to analyze the temporal and spatial variations of heat islands of Isfahan using the principal component analysis method. With this technique, it is possible to identify the seasons and months when the land surface temperature and the heat island increased. 

In this regard, the present research considered analyzing the temporal and spatial variations of this phenomenon in Isfahan during a period of 20 years (from 2000 to 2020 AD). To achieve this purpose, the land surface temperature (LST) data extracted by MODIS sensor and Terra satellite was used. These data are available for the whole world with a time resolution of 8 days and a spatial resolution of 1x1 km in a sinusoidal grid with dimensions of 1200x1200 km. Therefore, for Isfahan, 913 images were extracted from the MODIS sensor. Then, with the principal component analysis (PCA) method, the seasons and months that have the most influence on the occurrence of heat islands were identified and in order to analyze the trend of this phenomenon, the Mann-Kendall and the Kolmogorov-Smirnov tests were used.

The findings of the research indicated that the land surface temperature in the last 20 years in Isfahan had an increasing trend with a rate of 4%. However, this trend in the population and urban centers has been completely different from the surrounding areas of Isfahan. In terms of spatial distribution, the highest occurrence of heat islands has been registered in the eastern and southeastern parts (including Hassan Abad and Jolgeh) due to proximity to the hot deserts of Kavir-Lout, proximity to Sepiddasht, Varzaneh, Shahrak Ramsheh industrial towns and changes in the land use of agricultural to industrial and residential. also in the North-West region (including Mahmudabad and Isfahan city) due to the increase in man-made heating caused by the increase in the consumption of fossil fuels, the growth of residential, industrial and commercial units, temperature has risen. In addition, the results showed that the intensity of the heat island in winter is higher than in summer, and the most intense time of its occurrence was recorded in January and the least in November.

Isfahan is integrally affected by global climate conditions, but depending on the geographical location of each part of this province, the land surface temperature and the occurrence of heat islands are different, so that, eastern and central parts, adjacent to Kavir-Lout and close to industrial towns, have an increasing trend. Moreover, the southern parts have a decreasing rate of temperature and heat islands due to less urban population, larger agricultural lands and more vegetation. The increase in urbanization, migration, and the increase in fossil fuel consumption, the decrease in vegetation, the aggravation of drought, and the change in land use have a fundamental role in increasing the occurrence of this phenomenon.

Oilseed rape (Brassica napus) is considered as a strategic crop by the Ministry of Jihad-e Agriculture. Birds are important pests of this crop that cause severe damage to the oilseed rape plant every year. Bird damage to oilseed rape was noticed because of edible oil import and the importance of self-sufficient production in Iran. Bird damage occurs in the early stages of oilseed rape cultivation by larks. If they gather on oilseed rape fields, they would cause significant and economic damage extents. As using pesticides is generally forbidden for bird damage control around the world, the use of chemical repellents is recommended. Chemical repellent compounds affect sight, smell and taste organs of birds to deter them. 

We implemented an experiment using a Completely Randomized Block Design with three repellents (Methyl Anthranilate, Cinnamic Acid and Ammonium Aluminium Sulphate) in field conditions. Experiments were implemented in Ilam and Mazandaran provinces in 1000-m2 plots. Treatments were applied with the following doses: 1. Methyl Anthranilate 3400g/hec, 2. Cinnamic Acid 2000g/hec, 3. Ammonium Aluminium Sulphate 50g/lit and 25kg/hec, and 4. Control. In every sampling time, ten quadrats of 1*1 m2 were randomly applied in each treatment. The total number of damaged and undamaged plants were registered and the percentage of damaged plants was calculated accordingly. Results were analyzed using SPSS 17.0 software.

Based on the results, all three treatments had significant differences from control. In Ilam, Cinnamic Acid had a lower damage rate (1.58%) in 2017, and Methyl Anthranilate showed a lower damage rate (13.7%) in 2018. In Mazandaran, Ammonium-Aluminium Sulfate showed a lower bird damage rate (23.0%) compared to control (49.2%). In both regions and years, bird damage was significantly different among weeks. Also, independent and composed effects of treatments and weeks were significant in both regions and years. Regarding the mode of action of the treatments, Cinnamic acid with unpleasant taste and white color was the most effective treatment, oily Methyl Anthranilate also made an unpleasant smell. Ammonium-Aluminium sulfate has also reduced bird damage with salty and bitter tastes simultaneously. Cinnamic acid and Methyl Anthranilate should be imported, while Ammonium-Aluminium sulfate can be produced inside the country.

All the treatments made less bird damage rate and among them, Cinamic acid had multiple effects. The results of this study raised hopes for making new national and cheaper compounds that have multiple effects on the sight, smell and taste organs of birds.

Rivers are considered as a vital resource for mankind from the past to the present day.Considering the ever-increasing population, industrial developments and the expansion of modern urban societies, it is expected that the rivers located near densely populated urban and rural areas to be in danger of destruction due to a large part of urban, rural, domestic, industrial and agricultural pollutants to the sources of surface and groundwater in the riparian and riverside more than any other water ecosystems. On the other hand, regarding Iran's arid and semi-arid climate, the use of sediment qualitative indicators in research and investigation is crucial in order to predict, evaluate and provide a sustainable solution for controlling the amount of pollutants and also improving the quality of river water. The Karaj River is one of the main freshwater and energy production resources in the region, which plays a vital part in creating an ecological balance in parameters affecting the quality of this water ecosystem. The purpose of this research is to measure the concentration of heavy metals in the sediments of the river bed and to evaluate and analyze it using Geoaccumulation index and Enrichment Factor, which led to the suggested solutions in order to avert and control the further spreading of pollution.

In this research, nine stations were selected based on the land use of the area. The sediments of the river bed in each station were sampled. Sediment samples were prepared and later transferred to the laboratory and the total concentration of heavy metals was measured by Inductively Coupled Plasma Mass Spectroscopy (ICP) device.

The results obtained from the measurements using the mentioned indices assessed that the level of heavy element pollution is relatively low in the Karaj River. Nevertheless, part of this slight pollution is related to human activities such as road construction, tourism and the leakage of local runoff and sewage into the river and its riparian zone, which led to the increase of the Geoaccumulation of elements including copper and chromium to the numbers of 1.01 and 1.96 in downstream stations P8 and P9, respectively. Also, the highest average amount of Geoaccumulation for copper in 9 sampling stations was 0.23. On the other hand, these anthropogenic activities have significantly increased the arsenic Enrichment up to 17.81 in station P4 and the average Enrichment Factor of Arsenic in 9 sampling stations up to 13.12. But since each heavy element has its own unique nature, part of the quantity of the pollution present in the sedimentary environment of the river is related to natural factors, geology, soil erosion and weathering of riverbed rocks.

The process of changes in the amount and distribution of elements in the sediments were compared and the factors affecting their alignment or mismatch were discussed and researched. Generally, the results of this research show that the Karaj River, taking into account the Geoaccumulation index and Enrichment Factor, has negligible contamination of heavy metals in the riverbed sediment. However, the trend of index changes along the river route shows the direct effects of destructive human activities in the region.

Soil is the largest source of carbon in the biosphere and more than half of its carbon is stored in forest ecosystems. Considering the importance of the soil carbon, the purpose of this research is to investigate how different species of broadleaf and coniferous species affect forest carbon storage in soil, considering their different ability to store and use soil nutrients in the forest Kolet.

In this research, first, three stands of Acer velutinum Boiss, Alnus subcordata C.A.M, and Cupressus sempervirens var horizontalis, as well as one natural forest stand were selected in the study area. Ten samples of 400 square meters (20Î20 meters) were selected in each cluster. Also, soil samples were collected from the four corners and the center of each plot from a depth of 0-15 cm; Then the soils were mixed and a combined sample was separated for the laboratory analyses (40 samples in total), which was used to study the physical and chemical characteristics of the soil (bulk density, soil texture, soil reaction, electrical conductivity, organic carbon, total nitrogen, phosphorus and absorbable potassium). SAS statistical software was used for soil data analysis related variables, and the Vegan R software package was used for principal component analysis (PCA) to identify the most significant factor and differentiate between the studied populations.

Based on the obtained results, soil reaction rate, absorbable potassium, relative humidity, organic carbon, clay and soil carbon storage had significant differences among the four stands (P < 0.01). Alnus subcordata and Acer velutinum showed the highest amount of carbon storage compared to Cupressus sempervirens and natural forest stand. The difference observed in the amount of soil organic carbon in the studied stands depended on the different capabilities of tree species in restoring the soil ecosystem. The planting of broadleaf species resulted in more carbon storage in the short term than coniferous species, because broadleaf tree species increase litter production and nutrient return, making them more effective in restoring degraded forest soils. This is due to faster leaf decomposition, higher nitrogen content and lower C/N ratio, while the presence of resinous and phenolic substances in coniferous leaves negatively affects the decomposition of their litter.

In summary, this research showed that reforestation with broadleaf species in various areas of the region significantly impacted the soil carbon stock and carbon storage potential based on the type of tree species. Particularly, broadleaf species such as Alnus subcordata and Acer velutinum played a crucial role in increasing the amount of carbon stored in the soil of the studied region.

With the development of sciences and technologies, the growth and expansion of cities led to the destruction of the environment and production of various biological pollutions across human societies. Meanwhile, noise pollution has been one of the types of pollution that has adversely affected the comfort of urban residents and is found to be directly associated with the mental health of people in society. This type of pollution may cause mental diseases, irritability, allergies and other nervous and psychological diseases. This paper aimed to evaluate the noise landscape of District 4 of Tabriz and investigate the amount of this type of pollution in the peak hours of activities in this city, as well as the impacts of social, physical and environmental variables on the urban environment.

This paper used a methodology that combined descriptive-analytical, documentary and survey methods. District 4 of Tabriz was divided into squares of 200*200 m in dimensions, based on a standard square grid, with the center of each square designated as the noise acquisition station. The equivalent continuous sound level (Leq) of each station was measured for 3 minutes at two-time intervals of 8-11 a.m. and 7-10 p.m. in June to December of 2021. Noises were acquired by using a decibel meter device at a sound pressure level of Grid A with a Fast Response Speed. The dependent variable was the equivalent continuous sound level (Leq) at two morning and afternoon time intervals and independent social and physical variables were population density, construction density, the distance from pathway grids, the distance from administrative and police uses, the distance from educational uses, the distance from urban installation and equipment uses, the distance from commercial and service uses, the distance from treatment uses, the distance from industrial uses, the distance from barren land, the distance from green spaces and the distance from aerial corridors. Each of the maps pertaining to the independent and dependent variables of District 4 was separately sketched in GIS software, and then, the effects of each of the independent variables on dependent variables were examined by using a linear regression model in SPSS software.

Surveys indicated that the noise landscape of District 4 of Tabriz Metropolitan consisted of children game noises, noises caused by vehicle and motorcycle traffic, trash trucks when loading trash bins and the sound of construction workers across the neighborhoods, noises caused by motorcycle horns and their swerving noise, the passage of trucks and vans, as well as motor vehicles on the streets and other main axes, the traffic noise of inter-city buses and their horns, load trucks, international transit trucks on first degree axes (Pasdaran Highway and Santou Road), etc. The evaluation of independent social and physical variables with dependent variables (sound equivalent level (Leq) in the two intervals of morning 8 to 11 and evening 19 to 22) shows that out of 12 independent variables of district 4 of Tabriz metropolis in the morning time interval, 9 independent variables of population density , building density, distance from road network, distance from administrative and law enforcement use, distance from urban facilities and equipment use, distance from medical use, distance from industrial use, distance from green space use and in the evening period, 7 independent variables of population density , building density, distance from road network, distance from medical use, distance from industrial use, distance from green space use and distance from air corridor have a significant effect on the sound equivalent level (Leq) and the level of noise pollution in district 4 of Tabriz metropolis. And the variables of distance from administrative and law enforcement use due to the closure of this use in the evening period and commercial and service use despite the high population density of this use but due to the high distribution in the localities of the region, the distance from it do not have an effect on the sound equivalent level (Leq).

Linear regression model results for evaluating independent and dependent variables (equivalent continuous sound level (Leq)) at each time intervals (morning and afternoon time intervals) indicated that the semi-eastern neighborhoods of District 4 suffer from higher noise pollution, while semi-western neighborhoods were dealing with lower amounts of nose pollution.

Providing a palynological database is one of the important measures in order to manage the environment of Tehran Metropolises. This database can also be used for the Pollen Atlas of Iran, pollen calendar, aerobiology, climate change, botany, the management of asthma and allergies, archaeological as well as melissopalynological studies in Tehran. Up until now, little attention has been paid to this scope, so it seems to be necessary to prepare the mentioned database. The aims of this study is to prepare SEM images of pollen grains, describe the diagnostic characteristics of pollen grains and analyze the characteristics of pollen grains in relation to allergenic properties.

Plant samples of this study were collected from parks and various urban green spaces as well wildlands in Tehran during 2001 to 2021. It was also deposited in the herbarium of Shahid Beheshti University (HSBU). These specimens were identified using scientific sources such as Flora of Iran, Flora Iranica, Flora of Tehran, Flora of Turkey, Flora of USSR and some illustrated guide on garden plants. Therefore, the pollen grains were photographed using Scanning Electron Microscopy (SEM). The 12-20 pollen grains of each species were evaluated using Image Tools 3.6 software to evaluate quantitative morphological traits. The terminology used to describe the pollen charactersaccording to Erdtman, Punt, and Hesse. Finally, a comprehensive description of the quantitative and qualitative morphological traits of pollen grains was prepared.

In this study, pollen grains of 92 species belonging to 42 trees and herbaceous plant genera were studied. The Asteraceae with 11 species had the highest number of species in this study. The pollen grains included monad (91) and tetrad (1). Also, 70 species are isopolar and 22 species are heteropolar. Sculpturing includes 16 different types. Pollen ornamentation including 16 diverse types that reticulate, microreticulate as well peforate have the highest abundance in the studied species. The 35 plant taxa have allergenic properties based on previously published scientific studies.

This study is the first illustrated pollen database on Tehran including 92 plant species belonging to 42 families of cultivated trees as well as wild herbs. The results of this study showed that several species have been planted regardless of their allergic effects. In addition, this study provides an important reference for allergy studies. Finally, pay attention to the planting of Non-allergenic plant species is one of the important ecological considerations in city management.

Soil contamination with potentially toxic metals is one of the most critical challenges in terms of food and human health safety. The majority of the studies on metal pollution of agricultural soils have been carried out by analyzing the total concentration of metals in the soils. However, metals are present in different chemical forms or species in soils, so they should be considered in a full-fledged environmental assessment. The purpose of this research is to assess the total concentrations, pollution level, source and speciation of potentially toxic metals in agricultural soils of Jovin Plain in Razavi Khorasan Province.

Twenty-seven soil samples were randomly collected from the entire plain at a depth of about 50 cm. Soil physicochemical parameters (organic matter, pH, carbonate content, soil texture) along with the total concentrations of potentially toxic metals (zinc, cadmium, arsenic, chromium and nickel) were measured using standard methods. The level of soil metal pollution was assessed by calculating pollution indices (enrichment coefficient, land accumulation, pollution load index) and their possible origins were apportioned by multivariate statistical methods (correlation and principal component analysis). The modified four-step BCR method was used to determine the species or chemical phases of metals in soil samples.         

It was found that the cultivated soils were alkaline in nature, clay loam in texture and moderate in terms of organic matter content. In majority of the soil samples, the concentration of all studied metals was higher than the mean crust and the global mean soils. Evaluating the level of soil metal pollution also showed that the soils were moderately to heavily contaminated in terms of chromium, nickel and copper and heavily contaminated in terms of arsenic and zinc. The results of the multivariate statistical analysis revealed that chromium and nickel are mainly of geogenic sources attributable to the ophiolite rocks in the region, while zinc, cadmium, copper and arsenic were mainly derived from anthropogenic sources e.g. agricultural activities in the study area. Based on speciation analysis studies, chromium and nickel were mainly extracted from the residual phase (F4), zinc and copper from the oxidizable phase (F3), arsenic from the reducible phase (F2) and cadmium was mainly retrieved from the soluble/exchangeable phase (F1). The high extraction percentage of chromium and nickel from the residual (stable) phase indicates that the source of these metals in the soils was mostly geogenic with very limited mobility and bioavailability. On the other hand, the high percentage of metals retrieved from the first three phases (F1+F2+F3) revealed that they were mainly from anthropogenic sources having high mobility and bioavailability in soil samples.

Based on the assessment made in this research, it was found that the metals in the agricultural soils of Jovin Plain have surpassed the standard guideline limits and apart from chromium and nickel, the other studied metals have been derived from anthropogenic sources (agricultural activities) in the study area. The chemical speciation analysis also showed that the metals in the soils occurred in different chemical forms or phases depending on their different origin and pollution level, which in turn lead to the different mobility and bioavailability of these metals in the soil samples.

Extracting honey from beehives is one of the economic activities for local communities, which is effective in the direct and indirect employment of villagers and as a result, the sustainable development of these areas. Among the pollinating insects, bees play a much more prominent role, and usually the location of the hives can determine the extent of benefit from this ecosystem service. Among bees of Iran, Carnica hybrid (Apis mellifera meda) has a special place in honey production. Despite various studies conducted on this hybrid, so far none has investigated the suitable conditions for the placement of beehives of this species, so this study seeks to identify suitable areas for the establishment of beehives. Awareness of the areas that are prone to beehive placement can be one of the priorities of the planners in the field of agriculture and animal husbandry in Markazi Province.

In this study, in order to model the areas that are susceptible to pollination, variables such as spring density, height, topographic humidity, light shade, average spot size, land use/cover, landscape diversity edge density, distance from agricultural land, average wind speed up to a height of 10 meters, roughness of vegetation and vegetation density were used. Since it is difficult to access all the areas that are not suitable for the establishment of hives in the modeling process, alternative methods such as pseudo-absence methods were used. However, identifying suitable areas for recording pseudo-absence points can also result in errors. Therefore, first, using the output of presence-only models, pollination desirability was calculated. Then, by subtracting the desirable areas from the entire surface of the land, pseudo-absence points were randomly created in the remaining areas. After preparation of this group of points, the presence/pseudo-absence models were ready to be implemented. In order to evaluate distribution models, TPR variables and the Kappa index were used. TPR, which is also referred to as sensitivity, is a numerical value that identifies the percentage of presence points that are detected again after applying the presence point threshold. Also, a random forest model was used to calculate the impact of this data set on environmental changes.

The presence-only models in this study were implemented with adequate power. The value of AUC was calculated as 0.89, 0.90 and 0.76, respectively, for Bioclim, Domian and single-class support vector machine models. The results of the evaluation of the used models showed that all models have well predicted the presence of beehives in the areas of pseudo-absence of beehives. The Kappa index for this category of models was at least equal to 0.83. On the other hand, based on the TPR criterion, many of the hive points have been detected again after applying the hive threshold, which can indicate a good level of prediction of the used models. Also, the findings showed that the diversity of the landscape had a greater impact on the quality of pollination than the proximity to agricultural lands. The height of up to 1813 meters above sea level, as well as the wind speed of 3.47 meters per second, were the best conditions for the presence of beehives. Among the different cities, Arak, Farahan, Khandab, Shazand and Khomein had the highest value for pollination.

Planning for the protection of natural areas as well as areas prone to the establishment of beehives can be done with emphasize on the location of Arak, Farahan, Khandab, Shazand and Khomein cities. The findings of this study show that the use of species distribution models can be effective in identifying suitable areas for beehive establishment and pollination activity. On the other hand, combining the findings of this group of studies with other spatial data that determine the patterns of the landscape can provide a clear view of the influence of the landscape.

Goods and services that are provided by ecosystems in favorable environmental conditions, for the welfare of humans, are called ecosystem services. Recreational ecosystem service, which is in the category of cultural services, is one of the most valuable services in urban ecosystems, which increases the physical and mental health of the urban residents. Recreational value is defined as the capacity of ecosystems to provide recreational opportunities such as walking, cycling, plant and animal viewing, running and outdoor sports. Due to the importance of ecosystem services, the present study was conducted with the aim of evaluating and quantifying recreational services in Behbahan county.

In this study, a combination of Landsat 8 and Sentinel 2 images was used to prepare a land use map for 2021. The image was prepared with the maximum Likelihood algorithm in 12 class. Outdoor recreation was also modeled by the Recreational Opportunity Spectrum (ROS) method. In this model, the final recreation map is classified into 9 classes. This model can be used in almost all surveys of the landscape and it is a practical process with principles that force managers to justify management from the three perspectives of resource protection, opportunity for public use, and meeting favorable conditions in the region.

The results of recreational ecosystem service supply in Behbahan county show that the sixth Category (Medium provision - not easily accessible) and the eighth Category (High provision - accessible) in the current situation have the highest and lowest land cover, respectively. The places in the northeast of the region have the highest recreational potential due to the location of the Maron Dam and the protected areas of the city. In addition, there are no human activities and aggregation of urban areas in these Places. In the center of the region, due to the accumulation of urban areas and the network of roads, the recreational potential is at its lowest. Also, parts of the south and west of the region have relatively favorable recreational potential. The composition of the area cover in these parts includes water areas and dense range. According to the results, recreational opportunities were affected by topography. Because in the northern landscape, due to the mountainous nature and other natural attractions (water bodies, forests and protected areas), there are more recreational opportunities than the center and other parts which is located at lower altitudes and is mainly covered by human activities. In addition, places with low population density and far from the city center and roads always show a higher opportunity for recreation.

According to the results, understanding the environmental effects of land use change and urban sprawl on recreational ecosystem service may help to achieve cost-effective results in the future. In this regard, policymakers and planners of Behbahan county should focus on improving leisure opportunities in the central, southern, western and southwestern regions. Due to the fact that recreational ecosystem service in Behbahan county is different in different places, thus, this result highlights the importance of using the value of ecosystem services in urban planning and policy priorities.

achieving urban water security is a major challenge for many countries. urban water security has created significant concern for urbanization and climate change. Having systems thinking and integrated management can help to understand the mechanisms that affect the long-term water security of a city. Today, the metropolis of Ahvaz has become one of the largest cities in Iran due to the development of economic, social, cultural, and political activities with the growing population. Considering that the process of urban construction and development and excessive population growth in this metropolis was not subject to a pre-determined and codified plan and its water supply and distribution plans were not consistent with the increase in population; Therefore, in this city, like all the big cities of Iran and the world, there are various problems in terms of water security. Global climate change, geographical features of this metropolis, environmental issues, pollution of water resources and insufficient water resources for the current population on the one hand and the other hand the increasing industrial use of water, the existence of large industries, and new and growing cities and towns around this The metropolis as well as the huge consumption of water in the agricultural lands around the city of Ahvaz has made the water resources more limited. The continuation of this trend is all reason for the need for comprehensive planning and assessment of water security for the future. to analyze the trend of changes in climatic parameters of precipitation and discharge of Ahvaz station, the period of 70 years ( 1330 - 1400 ) was studied And the time trend of changes in the aforementioned climatic parameters was calculated using the Menkendall non-parametric test in the monthly, seasonal and annual time series during the statistical period of the study. The results showed that during the studied period of the year, there have been changes in climatic parameters in the city of Ahvaz in the form of a decrease in precipitation and a decrease in discharge, and this has had consequences for the metropolis of Ahvaz. This study presents a systematic approach to better understanding urban water security, with a working definition and an assessment framework for application in urban areas. The assessment framework for achieving urban water security depends on four main dimensions: Drinking water and humans, ecosystem, climate changes, and risks related to water and socio-economic factors. This framework allows further analysis of the relationships and trade-offs between urbanization and water security, as well as between the aforementioned indicators. Applying this framework will help governments, policymakers, and water stakeholders target scarce resources more effectively and sustainably. This study shows that achieving urban water security requires a comprehensive and integrated approach with common stakeholders to provide a meaningful way to improve the management and understanding of urban water security.