vahedberdi sheikh

Large-scale and regional planning requires observed data on environmental variables, such as runoff and suspended sediment load from watersheds. Data is fundamental for generating information and knowledge, and scientific management of a system is impossible without a monitoring and measurement plan. Management of watershed systems and water resources is no exception to this axiom. With ongoing trends in socioeconomic development, climate change, increasing pressure on natural resources and watersheds, and, consequently, an increase in floods and sediment yield, there will be a greater need for more accurate information about sediment and runoff processes in the near future. Many tools and instruments for measuring runoff and sediment components have been produced and marketed by a number of foreign companies. However, their cost is very high in Iran, on the one hand, and a device that measures both components at once is very rare, on the other hand.To carry out simulations that are both accurate and efficient, it is essential to have access to sufficient and reliable data and information for verification and validation purposes. In the field of water resources and watershed management, data and information are considered to be crucial tools. By providing important insights into the management of water resources, the availability of data and information can help enhance the efficiency and optimization of water usage, prevent natural hazards (such as floods and droughts), manage water quality, and improve the management of water supply and demand. Therefore, this study aimed to design and construct an automated flood and sediment load-monitoring device with the ability to record the runoff height of watersheds and a planned sampling of runoff for measuring suspended sediment using cheap sensors and tools.

This study presents an innovative device designed to monitor runoff discharge and suspended sediment sampling. The device has been constructed and installed at the outlet of the sub-basin under study. A regular cross-section was constructed at the outlet to facilitate the installation of the device, which enabled the monitoring of the runoff hydrograph of the sub-basin outlet and suspended sediment load sampling. In this research, analog hygrometer sensors were used to measure the height of runoff with 3 cm intervals (measurement accuracy of 3 cm). DC pumps with valves were used to collect the sediment sample, which created a vacuum in the sampling container and caused the runoff sample to be transferred into the container. To evaluate the device's capabilities in real and natural conditions, it was installed at the outlet of a sub-watershed in the eastern loess lands of Golestan province, located upstream of Qapan Oliya village in the Kalaleh district for two years to record the hydrograph of likely flood events and take runoff samples at the user-defined depths of flood (two samples at depths of 20 and 60 cm in rising limb and one sample at a depth of 20 cm in recession limb of hydrographs). The samples were stored in 0.5 liter containers, and the user was informed by sending an SMS to replace the filled containers with empty ones. It is noteworthy that the device under consideration facilitates the collection of runoff samples at any frequency and at any height for research requirements. The device boasts a remarkable advantage in the form of its SMS notification feature, which keeps the user informed about the monitoring site and equipment status, including runoff sampling, power outages, and battery status. The device incorporates a built-in battery that remains active during power outages in the electricity network to record flood events. Additionally, the user can communicate with the device via a mobile phone at any time and receive SMS updates on the device's operating status, such as power, battery, memory level, and event registration. Furthermore, to ensure accurate rainfall data recording, a WatchDog tipping bucket rain gauge has been installed within the studied sub-basin.

During these two years, only three rainfall events leading to runoff and flooding occurred in this sub-watershed, and the designed device successfully recorded the hydrograph of all three events and informed the user. In each of these recorded flood events, at least two runoff samples (one sample in the rising limb and one sample in the recession limb of the hydrograph) were collected and stored by the device to be transferred to the laboratory to determine the suspended load. The present study has demonstrated that the automated runoff and sediment monitoring device, which has been specifically designed to measure a range of parameters such as flow rate, water level, and suspended sediment load, represents a valuable and practical tool for those seeking to monitor runoff and sediment at the outlet of watersheds.

Data and information play a vital role in water resources and watershed management. The availability of such data and information in the management of watersheds and water resources helps enhance water use optimization and efficiency, prevent natural disasters such as floods and droughts, manage water quality, and improve water supply and demand management. Therefore, the prototype of the designed device shows that this device has a good capability for the industrial production of an inexpensive runoff and sediment monitoring tool to scientifically manage small-scale watersheds.

Climate change though changing weather patterns can lead to global warming which emerges as change in the climatic extreme indices and disorder in the ecosystems functions resulting in serious environmental consequences. The analysis of extreme values is of vital importance in the planning and policy-making in the agricultural sector and water resources management. In this study, daily timeseries of precipitation and temperatures from a number of synoptic and rain gauge stations within and around the Hablehroud watershed have been analyzed for the statistical period of 1986 – 2017. To this end, the trend of 27 rainfall and temperature indices defined by ETCCDMI expert group was analyzed using the RClimdex software package. The results showed that the majority of the hot temperature indices have experienced a statistically significant upward trend in the study area. Both the monthly maximum value of the daily maximum and minimum temperature, Monthly minimum value of daily maximum temperature, Monthly minimum value of daily minimum temperature, the percentage of summer days (days with a temperature of value more than 25 oC) and tropical nights (nights with a temperature value more than 20 oC) indicate a statistically significant upward trend. Percentage of warm days and nights show a significant upward trend in all the studied stations, while percentage of cool days and nights in all stations present a statistally significant downward trend. Also, the number of stations that show an upward trend for precipitation indices is more than the number of stations showing a downward trend. Annual rainfall in half of the stations shows an upward trend and in the other half a downward trend, although in most cases these trends are not statistically significant. Generally speaking, due to high variation and low amount of rainfall in most of the stations, a specific and uniform pattern in the trends of precipitation indices across the study area is not detectable. However, despite a general perception that climate change has resulted in decrease in precipitation, the recorded long term data at the monitoring stations across study area favours the presence of an upward trend in most precipitation indices.Therefore, it can be concluded that significant climate change such as temperature increase has occurred in the region, but it cannot be said with certainty that statistically significant rainfall changes have occurred in the region.

The complex knowledge of local communities on the full cycle of disaster risk management has been proven valuable in various researches. However, the scientific literature still lacks studies that examine how to use Local Knowledge (LK) and the local people capabilities for crowdsourcing in Flash Flood Early Warning Systems (FFEWS) studies. Hence the main target of this research is investigation on the capacity of crowdsourcing for FFEWS and identification of Flash Flood Hotspots (FFHs) by LK across a flood prone area in northeast of Iran.

In this study, a questionnaire with three different themes was designed. The first theme was related to the individual characteristics as independent variables, the second theme addressed the residents’ LK in determining the FFHs, the type and the predominant time of the flood occurrence in the region, through asking open ended questions with short-answers. The last theme addressed the assessment of people's capacity in Flash Flood Crowdsourcing (FFC), through asking questions with a Likert scale of 0-5. The face-to-face questionnaire administration mode was used for public survey through conducting oral interviews and live discussions.

The results showed that there was no significant correlation between the individuals’ characteristics and their willingness and motivation to participate in FFC. Comparing residents’ LK with the 31-year flood report and literature review showed that the residents’ LK about the flood occurrence location, time and type on a local scale was very promising. The research results indicated that the respondents show highest level of willingness for participation in the release of flood warning messages with an average score of 4.23 and the most important motivating factor for their willingness to participate was introduced saving relatives, fellow villagers, and human being from flood hazards with an average score of 4.84.

In most of previous studies that have focused on the development of FFEWS, very little attention has been paid to understanding the needs of citizens and promoting their participation. In fact, there is a research gap regarding the method of citizen’s participation and their potential support for FFEWS. Hence in this research, an attempt was made to take a small step towards filling this gap by investigating LK, motivation and willingness of local residents to participate in various aspects and steps of FFEWS. Our findings indicate that involving local people in FFEWS has various unknown aspects that should be explored through more extensive and detailed studies.

The hills surrounding the international wetlands of Almagol and Ajigol in the Golestan Province are exposed to severe erosion and every year a large amount of sediments from these hillslopes discharge into these wetlands. Whilst a large extent of these surrounding hills, covered with Biological Soil Crusts (BSC), has been destroyed due to lack of awareness of their values, sensitivity and ecological functions. Improving soil properties, preventing direct contact of raindrops with the soil surface, all indicate the important role of BSC in hydrological processes and soil loss control.

In this study, the role of BSC in the hydrological processes of dry areas was investigated using a rain simulator. After a field survey and evaluation of the area, different treatments including biological crust with a dominant lichen cover, biological crust with a dominant moss cover, an area covered with vascular plants, an area without cover and areas covered with a combination of moss and lichen were selected to perform rain simulation and compare their effects on the hydrological processes of the selected region. Rain simulation was done in 2×1 meter plots for 30 minutes and intensity of 82 mm per hour. The start time of runoff and the volume of produced runoff at the outlet of the plot were measured and recorded. Also, at five-minute intervals from the beginning of the simulation process, 500 ml runoff samples were collected and transferred to the laboratory for testing in order to estimate the sediment concentration and mass. In addition, the depth of the wetting front caused by the infiltration of rain was measured at the beginning, middle and end sections of the plots.

The results of rainfall-runoff simulations at a 2×1 m2 plot scale with a rainfall intensity of 82 mm.h-1 and a duration of 30 minutes plots, showed that the average mass of sediments from plots with the dominant cover of moss (104 g), lichen (91 g), lichen-moss combination (176 g) and bush (99 g) was significantly higher than bare soil (1133 grams). Therefore, in case of destruction of the existing BSC and the formation of bare lands, the sedimentation rate will increase by more than 5 times. A significant decrease in water infiltration into BSC causes a significant increase of 30-40% in runoff generation compared to the treatment covered with bushes and a significant increase of 8-18% compared to the bare soil treatment.

by reducing soil loss and sediment concentration, BSC cause the production and transfer of high-quality runoff to the wetlands and as a result maintain the ecological function and health of the region’s wetlands. The results of this research show the positive influence of BSC on the hydrological and ecological performance of arid areas in the north of Gorgan Plain and protection of Ramsar-listed wetlands in the region.

Estimating the amount and intensity of precipitation and its spatial distribution in various return periods is necessary for flood estimation hydrological models. This information is obtained based on traditional methods through intensity-duration-frequency curves with many assumptions, such as the choice of suitable distribution for each period, and the requirement of many parameters in different return periods. If a study area has incomplete data or a lack of data, traditional methods are limited. For this reason, the fractal method is used to transform the precipitation hyetograph in different durations and transfer the precipitation data from one place to another. The fractal method is a self-similar method; It means that every part of it is similar to the whole, like a pine tree, where every branch is like a whole tree. This method has high reliability, convenient access, and less number of parameters, which can be used to create daily precipitation data over long and short periods. It is noteworthy, that in the past valuable research has been done in the field of using the fractal theory to extract IDF curves. Nevertheless, in this research, in addition to extracting the characteristics of precipitation based on the above method in all the stations inside and outside the selected watershed, the spatial distribution of the rainfall intensity mapped based on the Co-Kriging method, and has been compared with the Ghahraman method.

The study area is the Tireh watershed in the Borujerd-Dorud region, which is located between east longitudes from ̍28˚48 to ̍17˚49 and north latitudes from 51˚33 to ̍35˚33. This watershed, with an area of 2127.28 km2, is in the northernmost part of the large Karun River watershed and in the south of Oshtorinan town. The average rainfall in the mountains and plain areas has been estimated as 611.4 and 410.6 mm, respectively. The average annual temperature of the plain with an average elevation of 1493.3 m is 13.4 ̊C and in the highlands with an average elevation of 2025 m, it is 8.5 ̊C. In addition, the amount of evaporation in the highlands and plains is 1852.2 and 2148.8 mm per year respectively. In this research, the maximum intensity and amount of precipitation were estimated based on the fractal theory using the daily precipitation data for 12 stations with a statistical period of 31 years recorded from 1990 to 2021. The research method was conducted based on studies of Azhdary Moghaddam and Heravi, (2018) in the following steps. A) data extraction of the maximum amount of precipitation in different durations of 1, 2 and … days B) determining the maximum intensity of annual precipitation by dividing the maximum precipitation values by their durations C) calculating the weighted moment of the data ( ) in different orders (r) and durations (d) and then drawing linear graphs on a logarithmic scale, D) and then, using the related relationship, the maximum rainfall was calculated in the specified duration and return period. Since hourly precipitation data are not available in most of the stations, therefore, at this step, the IDF curves were extracted using the fractal theory and were compared with the experimental method of Ghahraman (which is based on the maximum daily precipitation) by the Pearson correlation coefficient. The Co-kriging method was used to create spatial distribution maps of precipitation intensity and amount based on fractal theory. The geostatistical Co-kriging interpolation method is similar to kriging and auxiliary variables can be used for better spatial analysis. Optimal spatial distribution maps of rainfall intensity and amount are provided by the existing point data extracted from the fractal method, and introducing different auxiliary layers such as maximum daily rainfall in the 24-hour continuity period.

Fractal analysis of precipitation data showed that there is a linear relationship between scale power and moment order in all stations. Therefore, the maximum precipitation data in the study area have a mono-fractal nature, which means that by using the fractal theory, the precipitation data can be converted from one duration to another. The results of the density of precipitation zoning based on fractal theory using the Co-kriging method showed that the accuracy of interpolation increases with the increase of the return period. Indeed the calculated values have a suitable fitting with the observed values and are close to the fitted line. Contrary to this, the results of precipitation zoning based on the Ghahraman method using the Co-kriging method showed the most scattered points around the fitting line; which actually shows the low accuracy of this method in estimating and zoning the area precipitation. The results of the 24-hour rainfall interpolation error using the fractal method showed an increase in the RMSE value with the increase of the return period based on only the auxiliary variable of the rainfall intensity data produced by the fractal method. The RMSE was calculated based on adding auxiliary data such as the amount and annual average of precipitation and the value of the maximum one-day precipitation intensity of the original data to precipitation intensity prepared by the fractal theory. According to this, the RMSE in the return periods of 2, 5, 25, 50, 100, 200, and 300 years equals 0.09, 0.27, 0.74, 0.18, 0.25, 0.059, and 0.13, respectively, have a decreasing trend compared to the use of only auxiliary variable of precipitation magnitude. This composition has reduced the error criterion values to less than a fifth compared to the initial state (only by precipitation intensity covariate) in the return period of over 50 years.

The analysis of statistical moments showed that the precipitation maximum intensity data has a mono-fractal nature. In other words, the changes in the power of the scale are completely linear with respect to moment order, and it can be used to produce the data in different durations. The statistical analysis of the results of estimating the intensity of precipitation in the different return periods and durations with this method compared to the Ghahraman method showed that in most stations there is a significant relationship with a correlation coefficient of over 99 % at a confidence level of 99 %. Generally, the results of the spatial distribution error of precipitation intensity using the Co-kriging method based on fractal in the return periods of 2, 25, 100, and 200 years showed acceptably reduced interpolation error by adding different auxiliary data.

Arid and semi-arid areas often have sparse and scattered vegetation cover. In many arid regions of the world, open spaces between plants are occupied by particular living organisms called biological soil crusts (BSCs) or biocrusts. BSCs are the dense population of living organisms such as cyanobacteria, algae, fungi, lichens, and mosses in different proportions that live on the soil surface or within the upper few millimeters of soil. The aim of the present study was to investigate the effect of biological soil crusts on surface runoff quality in hillslopes around Ajigol Wetland in the Golestan Province of Iran.

The study area is located in the northern part of Golestan Province. Elevation in the study area ranges from 7 to 32 meters above sea level. The topography of the area is gentle and the land surface is composed of loess deposits. According to the climatic conditions, the research area is classified as arid and semi-arid regions. Due to a lack of rainfall, high evaporation, and uneven distribution of rainfall throughout the year, as well as high soil salinity, it has low-growing and weak rangeland plants. The vegetation in the area is composed mainly of annual grass species scattered heterogeneously. They often appear after rain events and have a short growth period finishing the life cycle in one season. In this research a field rainfall simulator was used. First, field visits were conducted to select places for positioning rainfall-runoff simulation plots in different types of biocrusts. To eliminate the effect of slope on runoff processes, locations were selected whose slope was around the dominant slope of the region (around 20 %). Rainfall-runoff simulations were carried out using a rainfall simulator over 1 x 2-m plots with and without biological soil crusts. The intensity of the simulated rainfalls was about 80 mm h-1 and the duration of each simulation was 30 min. The plots were positioned over five different types of surface cover including 1) dominant moss cover, 2) dominant lichen cover, 3) mixed (moss + lichen) cover, 4) dominant shrub (Artemisia spp.) cover, and 5) Bare land. Sampling and measurement of some runoff quality variables (sediment, electrical conductivity (EC), acidity (pH), color, and Total Dissolved Solids (TDS)) were conducted at 15-minute intervals during the simulation, plus one more sample from a mixture of runoff of the whole simulation. For some other water quality variables (organic carbon, nitrate, phosphorus, and potassium) measurements were made only at the end of the simulation from the total runoff mixture. The data were analyzed using graphical methods (plots) and statistical tests: analysis of variance (ANOVA), Kruskal-Wallis, and Tukey’s test.

The results showed that sediment concentrations were significantly (P ˂ 0.05) lower for biocrust-covered plots compared to the plots without biocrusts. Extreme differences were observed for the bare soil. EC, pH, color and TDS values also had significant differences between different covers. For organic carbon, phosphorus, nitrate, and potassium, no significant differences (P ˂ 0.05) between covers were detected by statistical tests though some notable differences were discernible on plots. The origin of runoff EC is mostly inorganic substances and it is caused by natural and human-induced pollution. There was a significant difference (P ˂ 0.05) between shrub-covered plots and plots with a combination of moss and lichen. EC for the shrub cover (Artemisia spp.) was found to be significantly higher than the mixed moss and lichen cover. The reason can be attributed to the increase in permeability and soil moisture in BSC dominated areas. Increased infiltration of water by biocrusts causes salts and ions to move deeper into the soil and this reduces the salinity of upper soil layer and surface runoff. With regard to runoff color, a significant difference (P˂ 0.05) was observed between bare soil and the other cover types. By producing polysaccharides and viscous materials, BSCs preserve and stabilize the soil surface materials and reduces the transport of metal ions (such as iron and manganese), decayed plant materials, organic matter, and animal waste as the main factors for the coloration of runoff. In contrast, more detachment and transfer of materials from bare soil have caused the runoff to become thicker and darker. The amount of sediment concentration from bare land was higher than shrubland and biocrust covers. For example, the average sediment concentration in the runoff from plots of bare land was about three times that of Artemisia plots. Another notable point was the large difference in sediment concentration between bare soil plots themselves. The reason for this was attributed to the presence of remaining roots of annual plants in the bare soil plots, which influence runoff and soil loss.

Overall, the results indicate the major effect of BSCs on runoff quality. So, taking proper measures to protect them and prevent their destruction is of great importance for soil and water conservation as well as water quality preservation in downstream wetlands. Therefore, it is necessary for government agencies to pay more attention to BSC-covered hillslopes around the Ajigol Wetland so no more damages are imposed on these fragile unique resources. As no comprehensive map of BSC covers the study area is present, it is recommended that such a map be prepared using satellite and drone imagery. Then, by combining the results of this study with the information obtained from mapping and generalizing it to the entire region, it is possible to make an overall estimate of the effect of BSCs on the water quality of downstream wetlands which is necessary for better-informed planning and decision-making. Exclosure and cover protection measures to prevent physical damages caused by human activities need to be implemented for the BSC-covered areas so they can continue their function as living mulch and protect soil from water and wind erosion.

Hydrological regimes play a major role in changing the structure and function of ecological processes and river ecosystems. Significant changes in the hydrological regimes of river flow cause the spatial and temporal heterogeneity of river systems and the degradation of natural ecosystem services and threaten biodiversity. Trend analysis and change point detection are important topics in the analysis of hydrological time series. The study area in this research includes the upstream part of the Hablehroud river basin draining to the Bonekoh hydrometry station, located within the jurisdiction of the Tehran province. The Habaleroud river as the main drain of this watershed has recently encountered the pressures induced by human interventions and climate change, resulting in significant changes in its hydrological status.

In this research, using the sequential Mann-Kendall, Pettitt, Buishand Range, Buishand U, Standard Normal Homogeneity, and double mass curve tests, the significant change point in the annual discharge time series (1980–2017) of the Bonekoh hydrometry station at the outlet of the Hableroud watershed was detected. Then, using the Indicators of Hydrologic Alteration (IHA), the alterations in the hydrological condition in the period after the change point (Altered flow regime) compared to the period before the change point (the natural flow regime) were analyzed using the daily observed discharge data of the Hableroud watershed.

According to the research results, in the mid-1990s, a statistically significant change point in the annual discharge time series of the Bonekoh hydrometry station occurred, and most of the hydrological indicators show a deterioration in the condition of the Habaleroud watershed flow regime. Whereas for most of the hydrological indicators, after the change point, the frequency of the low values category has increased and the frequencies of the middle and high values categories, have decreased. These reductions have not only occurred for high extreme values, but also for low extreme values. In addition, the mean monthly discharge for all months of the year and the base flow of the basin have decreased. Both the frequency and duration of low-flow pulses have increased. On the contrary, both the frequency and duration of the high-flow pulses have decreased. For this reason, the frequency and magnitude of high extreme events such as medium and large floods have decreased. The long-term trend analysis indicated that 25 out of the 33 IHA have experienced a statistically significant decreasing trend. Therefore, the mean annual discharge of the watershed at the Bonekoh station has declined from 8.43 m3/s during the pre-impact period to 5.43 m3/s during the post-impact period, which is equivalent to about 35 % decline in the watershed outflow. While the watershed’s mean annual precipitation shows a negligible long-term increasing trend. Therefore, it seems that human interventions across the watershed play a major role in the hydrologic regime alteration of the watershed.

In the Benkoh hydrometric station in the mid-1990s, the hydrological regime of the basin has changed significantly. Then, using special software, the hydrological change indicators and key environmental flow indicators were analyzed in the periods before and after the change point. Unfortunately, most of the hydrological indicators show a downward trend in the Habaleroud river flow. So that the average discharge has decreased in all months of the year. Base current values are reduced. Both the frequency and duration of minimum current pulses are increased. On the contrary, both the frequency and duration of maximum current pulses are reduced. For this reason, the frequency and magnitude of extreme events such as medium and large floods have decreased. The results of the analysis of the trend of several indicators of the environmental flow also indicate the regressive course in the ecohydrological conditions of the Hableroud watershed. So that the minimum monthly flows for all months of the year show a downward trend. On the one hand, the continuity and frequency of periods of water shortage has increased, and on the other hand, the frequency of high flow pulses has decreased. The consequence of these changes will be creating tension and threatening riverside plant and animal communities that live in the flood plains of rivers and provide many ecological services. On the other hand, with the destruction of these riverside communities, the hydraulic conditions of the floodplains have changed and the vulnerability of river ecosystems and infrastructure facilities around the river increases against possible floods and causes a lot of damage. With the continuation of the existing process of managing water resources of the basin, stakeholders and beneficiaries of the basin will face many challenges in the future. Due to the fact that the average annual rainfall of Hableroud basin does not show a decreasing trend, it seems that human interventions are one of the main factors affecting the hydrological changes of this basin. Therefore, it is suggested that the main focus of management policies and measures should be focused on the management and optimization of human interventions in Hableroud watershed. In other words, instead of focusing on the top-down management approach and (hard) structural engineering measures, the focus should be on the participatory management approach and (soft) management engineering measures, and the water and soil resources of this basin should be used optimally and in accordance with the principles of sustainable development, so that at the same time Reducing the conflicts between the beneficiaries and the stakeholders upstream and downstream of the watershed (social challenges and threats) which currently occurred on a larger scale between the two provinces of Tehran and Semnan, and also preventing these conflicts from occurring on a smaller scale between the smaller communities upstream and downstream in The extension of waterways and rivers in the basin prevented the occurrence and spread of diverse environmental challenges and threats and vulnerability to natural hazards such as sudden floods and droughts. Also, it is suggested that the future changes in discharge of the studied watershed should be predicted according to the results of climate change models and land use changes, and suitable solutions should be formulated and implemented in order to deal with or adapt to these changes.

In recent decades people around the world have embraced "smartphones" and their technologies. The application softwares (Apps) in these devices have become efficient and easy to use. Citizen science (CS) projects that attempt to collect data affordably from people of diverse backgrounds require the design and delivery of a user-friendly technology. In this research, an attempt was made, through reviewing the steps of designing a CS App to address the considerations and necessity of designing and disseminating a CS App with the subject of meteorology and hydrology. Payeshyar App that has been designed by the authors aimed at monitoring three parameters of air temperature, precipitation and water level in border and remote villages of Golestan. In order to gain sufficient experience, after placing simple and inexpensive measurement tools at the disposal of volunteers, the necessary data were collected for a period five months (December 2021-May 2022) via various communication methods including text messages, phone calls, paper and pencil forms and social media Apps. After that, necessary feedbacks and tips were recorded and according to the experiences gained, the initial version of Payeshyar was designed. In addition, in this research, by comparing the data collected through this App during eight months (June 2022 -January 2023) with the conventionally recorded data at formally established monitoring stations, its weaknesses and strengths were listed and its efficiency was investigated. Finally, the review of the effectiveness, advantages, disadvantages, limitations and challenges of Payeshyar showed that a well-designed Apps that can be installed and run on smartphones facilitates the communication of information from users to relevant databases and researches and seems that they are necessary to promote and expand long-term monitoring and surveillance systems based on CS. However, methods of sending meteorological and hydrological data to CS systems is a new field that needs more research.

Soil plays an important role in sustainable development. Therefore, protecting and controlling of soil erosion greatly contributes to the well-being, security and sustainability of societies. In order to solve the growing problems of the country in the field of natural resource destruction and soil erosion, assessment of farmers' awareness about soil erosion and their perception and attitudes toward soil erosion phenomena would be essential. Because perception is a kind of mental inclination and the main cause of behavior changes, and hence changing the perceptions alters human behavior. Hence, the study of people's perceptions in different fields would be important to help managers and executives to be aware of people's ways of thinking about specific issues, and if necessary, to develop some plans to change the people's perceptions. Therefore, the main goal of this research is to understand the perception of the farmers of the Chehlchay watershed in Golestan province towards soil erosion. Also, appropriate training methods, the effect of some human factors on soil erosion and the reasons for not implementing conservation works at the level of agricultural fields from the farmers' point of view are surveyed and is introduced as sub-objectives of this research.

In this study, to understand farmers' perception on soil erosion, a conceptual model with seven components including familiarity and understanding of the concept of soil erosion, the effect of natural factors on soil erosion, the effect of human factors on soil erosion, responsibility for causing soil erosion, the consequences of soil erosion, how to deal with soil erosion and control and prevention of soil erosion was designed and following this model, 45 items were defined to cover all aspects of this model. Then, 200 questionnaires were filled out with face-to-face interview with farmers in four villages and the results were analyzed. Statistical analysis of the questionnaires was performed using SPSS software.

In this research, Cronbach's alpha coefficient was estimated 0.804. The results of this research showed that about 31% of farmers have more than average knowledge of soil erosion, 22% have average knowledge and 37% have less than average knowledge. Also, the results of evaluating the scores of the seven components of the conceptual model of farmers' perception towards soil erosion showed that the farmers with an average score of 2.4, 2.3, and 2. 2 had the lowest level of awareness, respectively.

According to the presented data on the awareness of farmers in the region, in general, the majority of farmers (about 68%) have intermediate and low knowledge about the phenomenon of soil erosion, so it can be concluded that the farmers' low knowledge and inappropriate perception about soil erosion causes insufficient attention to be paid in this regard and therefore no serious works are carried out to improve the soil erosion in the region. Therefore, according to the significance of the relationship between the level of education and the amount of education and promotion about soil erosion, it is suggested that by improving the provision of educational and promotional services, a background is provided for improving the perception of farmers in the region. Additionally, by increasing the awareness of farmers, an effective step will be taken to improve the rate of soil erosion in the upstream watersheds.

Climate changes and human activities are the two main factors altering the hydrological cycle of watersheds causing changes in the spatial and temporal distribution of water availability. The river flow, as the most critical component of the hydrological cycle, is the most vulnerable component that is affected by these changes resulting in worrying consequences on water demand by different sectors. Since there is growing controversy on the contribution of two main factors (climate change and human interventions) affecting river flow alteration, assessment and quantification of their contribution is of utmost importance to the water resources managers. Quantification of climate change and direct human intervention contributions to streamflow alteration is a prerequisite for developing adaptation strategies and policies for regional water resources planning and management. To this end, various approaches and methods have been developed and proposed during the last decades in order to separate the contribution of natural and human-induced factors on river flow regime conditions. The current research investigates the contribution of climate change and direct human interventions on the discharge decline of the Hablehrood watershed.

In this research, the upstream area of the Hablehrood watershed draining to the Bonekouh hydrometry station, located within the Tehran Province jurisdiction, has been studied. The hydrological condition of the Hablehrood watershed, as a main drainage channel of the watershed, has drastically altered during recent years and its discharge has significantly decreased. In this study, first, the long-term statistics of Simindasht and Dalichay hydrometric stations were collected and subjected to pre-processing. Then, using the Pettit and Lanzante statistical tests, the significant change point in their annual discharge time series was identified. Then, the empirical methods of the slope change ratio of accumulative quantity (SCRAQ) and double mass curve (DMC) were applied to separate the effect of climate change and human interventions on the discharge decline of the Hablehrood watershed and its main tributaries. Since rainfall, temperature, and potential evapotranspiration are considered the main climatic elements in both the used methods, the relationship between discharge, and precipitation, between discharge and precipitation as well as temperature, between discharge and precipitation as well as potential evapotranspiration were analyzed in order to compute the contribution of climatic drivers first. According to the empirical methods, after calculating the contribution of climatic variables to the changes in water flow, the remaining changes in water flow are attributed to human interventions. In this study, the observed data from the hydrometry stations of Simindasht and Dalichay during 1980 – 2017 were used. For SCRAQ, the slope change of the ratio of cumulative discharge and cumulative values of rainfall and temperature as well as the slope change of the ratio of cumulative discharge and cumulative values of rainfall and evapotranspiration were computed to separate the effects of climate change and human interventions.

The results of both tests showed that the hydrological regime of the basin changed in the mid-1990s in both hydrometric stations and the average annual discharge drastically decreased in the period after the change point. Results of different calculation methods of SCRAQ (the slope change of the ratio of cumulative discharge and cumulative values of rainfall and temperature (first method) and the slope change of the ratio of cumulative discharge and cumulative values of rainfall and evapotranspiration (second method)) showed that human intervention is the main cause of discharge decline within the Hablehrood watershed. According to the first calculation method, the contribution of climate change on discharge decline at the Simindasht and Dalichay stations were, respectively, 15.53 % and -37.08 %, and for the second calculation method, 0.55 % and -39.72 %, respectively. The positive values for the contribution of climate change to the Dalichay station indicate that climate change has resulted in an increase in its discharge. Results of different calculation methods of DMC between cumulative values of discharge and climate variables showed that climate change has increasing effects on the discharge of both Simindasht and Dalichay sub-watersheds.

Human intervention is the main cause of discharge decline in the Hablehrood watershed and the contribution of climate change is very small and incremental in some cases, particularly for the Dalichay sub-watershed. Therefore, management policies and priorities should be focused on managing human interventions, promoting public awareness, optimal using of water resources, and preventing over-exploitation of water resources across the watershed. The results of this study can provide a scientific guidefor the development, utilization, and management of regional water resources and ecological environment protection.

Determining flood generation processes and incorporating them in hydrological studies can help make more reliable estimates. Focusing merely on mathematical computations in flood studies sometimes lead to paying less attention to the basic physical processes. Therefore, this research aims to present a process-based flood separation study for 20 hydrometric stations in the Gorganrood River Basin attributed as a flood prone area in the northern part of Iran. For this purpose, partial series of flood events at each station were extracted using the Peak-Over-Threshold (POT) approach selecting an optimal threshold value to determine flood events and considering the independence of the series values. Subsequent to characterizing flood events using some separation indicators including time of occurrence, rainfall duration, flood duration, air temperature, and antecedent soil moisture condition, different types of floods (i.e., floods caused by frontal precipitation, convective precipitation, snowmelt and rain on snow) were identified for each station. The results showed that floods caused by frontal precipitation and rain on snow have the highest and lowest frequencies in the basin, respectively. The research findings indicated that using POT approach and the indicators for classifying the different flood types can lead to a more accurate statistical analysis in flood studies and management.

Ecological services are the benefits that humans derive from ecosystems and include four categories of provision, regulatory, cultural, and supportive services. Each of these four categories includes a wide range of ecosystem services. In fact, climate control services include hydrological cycles, water supply and biochemicals, land-based processes and various biological processes. In this regard, to reduce the degradation rate and improve the condition of the Chehl-Chai Watershed in the northeast of Iran, several watershed management measures have been implemented.

The present study has investigated the extent of changes of supporting service (soil aggregate stability), provisioning (crops and fruits production, timber, and biomass production), regulating (control of soil erosion, runoff control, and carbon sequestration), and cultural (Increase of interaction and sustainability of local communities, increase of landscape aesthetics and tourist attraction and increase of knowledge and educational values) as a result of implementation of restoration measures in Chehl-Chai Watershed of Golestan Province. After quantifying the amount of services, prioritization of measures was done using TOPSIS method to identify and propose the most effective management option to improve services in the study area.

The results showed that the effect of watershed management measures on the ecosystem services improvement is not the same for all services, whereas it is highest for the regulating services and decreases towards the provisioning, supporting, and cultural services, respectively. Furthermore, the watershed management measures on improvement of the watershed services of treatment sub-watershed showed a statistically significant difference at the level of 5% (p<0.05). The results of applying TOPSIS method in the treatment sub-watershed showed that walnut orchards have provided the best effectiveness according to the indicators and criteria considered in the study. In other words, watershed management measures, through increasing the vegetation cover have led to more preciptation absorption, reduction of surface runoff and soil erosion in sloping lands and enhancement of landscape aesthetics as well as improvement of stakeholders participation level, social relationships, and income generation through conducting training and extension programs.

Among the employed measures, horticultural activities (planting walnut trees) have had the most success and if additional measures are taken and expanded, the success rate can be improved to a more desirable level. The watershed management measures are economically viable and can be implemented by the people. Therefore, in order to optimally manage water and soil resources and make watershed management more effective in improving the services of Chehelchai watershed, horticultural activities intercropped with forage and medicinal plants are recommended. In addition, the criteria, indicators and procedures applied in this study to quantify the effectiveness of watershed measures on ecosystem services can be consulted in developing a methodology or guideline for monitoring and evaluation of watershed management measures.

Determining the type, extent, and spatio-temporal changes of land use and land cover is very important in determining the hydrological characteristics of watersheds. Satellite data is the fastest and cheapest tools available to researchers in this regard. The study area in this study is Hablehroud watershed, whose flow decline over the past decades resulted in intensification of the conflict between the upstream (the Tehran province) and downstream (the Semnan province) stakeholders. Since, the land use change is considered one of the causes of the watersheds’ hydrological regime, this study aims detect, quantify, and predict the land use changes as well as to analyze the land surface vegetation cover in the Hablehroud watershed.

In this study, in order to identify the land use types of the Hablehroud basin, a supervised object-oriented classification of Landsat series images related to 1987, 2002 and 2019 was performed in Google Earth Engine software. To determine the classification performance, several ground truth points is required. In this study the ground truths were acquired through field visits and consultation of the high-resolution images of the Google map. The Markov chain and CA-Markov models within the MOLUSCE module, which is one of the software extensions of QGIS spatial information system software, wer used to simulate land use changes and analyze their dynamics in the study area. Moreover, the NDVI index was calculated to assess the spatio-temporal changes of the vegetation status of the study area through using the Google Earth Engine software.

The results indicate that the classification method used in this research has an overall accuracy percentage of more than 88 and a Kappa coefficient of more than 0.86 in all the time periods investigated. It is also observed in 2019, compared to 1987, we see an increase in irrigated arable land by about 67.5 square kilometers, an increase in rainfed agricultural land by about 20 square kilometers and an increase in residential areas by about 21 square kilometers. However, the grade 1 and 2 rangelands have decreased, which is about 240 square kilometers in the grade 1 rangelands and about 196 square kilometers in the grade 2 rangelands. While the extent of the poor rangelands has increased by about 327 square kilometers. If this trend continues, during 2019 - 2051, the extent of the irrigated areas, poor and medium class rangelands will increase about 20, 50, and 50 square kilometers, while the extent of the good rangelands will decrease about 127 square kilometers. The extent of the residential lands will increase too. trend. The results also show a significant downward trend in the average NDVI index of the basin, indicating retrogression in the vegetation status of the basin. Vegetation retrogression is more intense around residential areas and rivers and downstream areas of the basin.

The study of land use change trends in Hablehroud basin shows that due to human interventions, in significant parts of the basin, natural vegetation has been replaced by agricultural, horticultural and residential areas. The quality of the dominant natural cover of the region (rangeland) has also undergone a significant retrogression process Therefore, due to population growth, urbanization and development of industries and tourism, sharp decline in the discharge of the Hablehroud basin and the spread of conflict between stakeholders in the region, it is suggested that the main focus of the policies and management measures should be on effective planning, especially the management and optimization of human interventions through the development and implementation of land management plans and optimization strategies and save water consumption in this watershed.

 Aq Qala plain is one of the fertile plains of Golestan province. Runoff accumulation and flood formation cause a lot of human and financial losses. Understanding the temporal and spatial distributions of soil surface moisture is a key variable in simulating runoff and reducing flood hazards in the research area. In this study, the soil moisture content was investigated using data from ALOS PALSAR-2 radar satellites in the L band and Sentinel 1 in the C band.

 In this research, three series of ALOS PALSAR-2 radar data, Sentinel 1, and optical data of Sentinel 2A were used. To calculate the soil surface moisture, first soil samples were taken and weighed at a depth of 5 cm in each cluster by weight method. After drying the samples in the oven, the dry and wet weight was calculated. Then two important parameters of soil moisture, including dielectric constant and soil surface roughness were measured. The dielectric constant was calculated using TDR and the roughness was calculated using two digital cameras. Using Agisoft photo scan and Arc GIS software, a digital elevation model and surface roughness profiles were extracted. Radar data were processed with SNAP software from the European Space Agency (ESA). The processing steps included radiometric calibration, sigma note extraction in decibels, filtration of Lee filter and 5x5 kernel size, geometric correction and finally geocoding of all three data. With Sentinel-2 optical data, while preparing vegetation and moisture indices, a land-use map was prepared with the Forrest random algorithm. Then, with the values of roughness, dielectric constant and plant and moisture indices in MATLAB 2019 software environment, two models Oh, and WCM were coded and the soil moisture values were calculated and taken out. Then the moisture obtained from the surface redistribution model with gravity, moisture at the site, and previous studies was evaluated.

 In terms of radar signal sensitivity to soil surface moisture in Oh model in HH and HV polarization ALOS PALSAR- 2, in  with R2 = 0.86,  with R2 = 0.905 and for Sentinel-1 images, in  with R2 = 0.91 and  with R2 = 0.93 are sensitive to soil surface moisture. The surface backscattering coefficients sensitivity of the Oh model in ALOS PALSAR-2 in HH polarization and in HV polarization and for Sentinel-1 data in VV polarization and in VH polarization is sensitive to surface roughness. Also, the surface backscattering coefficients sensitivity of the Oh model in ALOS PALSAR-2 in HH polarization with R2 = 0.96 and in HV polarization with R2 = 0.94 and for Sentinel-1 data in VV polarization with R2 = 0.72 and in VH polarization with R2 = 0.74 is sensitive to surface roughness. Relationship between total surface backscattering coefficients obtained from the Water cloud model and soil surface moisture measured in HH and HV polarization PALSAR-2 images, in  and  with R2 = 0.73 and R2 = 0.399, respectively, and for Sentinel-1 data in polarization VV and VH, in  and  with R2 = 0.073 and R2 = 0.13, respectively, are sensitive to soil surface moisture. In the soil moisture estimation section based on Oh model for PALSAR-2 and Sentinel-1 data on bare lands in HH and HV polarization for PALSAR-2,  and  with R2 = 0.88, RMSE = 1.924  and R2 = 0.93, RMSE = 1.45  for Sentinel-1 data, respectively,  and  are with R2 = 0.81, RMSE = 2.57  and R2 = 0.97, RMSE = 0.90 , respectively. The results of Oh model showed that in HV polarization, Pulsar-2 images and VH sentinel-1 polarization images have stronger soil moisture results. Soil moisture results in WCM model in vegetated lands for PALSAR-2 images in HH and HV polarization in  and , respectively, with R2 = 0.81, RMSE = 2.44  and R2 = 0.78, RMSE = 2.64 , R2 = 0.88, RMSE = 1.924  for Sentinel-1 in  and  with R2 = 0.75, RMSE = 2.74  and R2 = 0.76, RMSE = 2.69 , respectively. In the discussion of estimating soil moisture with WCM model, the results of PALSAR-2 in polarization HH with R2 = 0.81  in lands with vegetation density of more than 0.4% have better results.

In the Oh model, the results showed that the sensitivity of HV polarization in PALSAR-2 images and VH polarization in Sentinel-1 in an area with vegetation density less than 0.4 is much higher than the polarization sensitivity of HH PALSAR-2 and polarized VV Sentinel-1. Also, the HH polarization sensitivity of PALSAR-2 and VH Sentinel-1 polarized images to surface roughness is higher than other polarizations. In the Water cloud model, the results obtained from Sentinel-1 data by eliminating the effects of vegetation and simulating the surface backscattering coefficients are very poor. Has reduced the penetration of the wave. The results showed that the polarization sensitivity of HH in areas with vegetation with a density of more than 0.4 was much higher than the polarization sensitivity of HV, also the sensitivity of the radar signal to noise was low in polarized HH but high in polarized HV. This showed that the polarization of the HH matrix is sensitive to vegetation, so the model will be more stable in the presence of vegetation. A comparison of two SAR data in the range showed that PALSAR-2 images are more efficient for estimating soil surface moisture in the study area and similar areas due to their long wavelength and depth of penetration into soil and vegetation. In line with the research topic, other researchers, including Alishan et al. A study has attempted to estimate soil surface moisture in barren lands using PALSAR-2 and Sentinel-1 data, which concluded that the WCM model eliminates plant water content. And surface moisture estimation using the inverse model was high in both PALSAR-2 and Sentinel-1 data. A study by Zaribi et al. Showed that the OH model in both polarized HV and HH with lower RMSE is able to estimate soil surface moisture. This research is suitable for environmental management, agriculture, natural resources, and water resources management and contributes significantly to hydrological modeling.

The present study is a new research in the field of ecosystem services and specifically ecosystem cultural services. Therefore, in this study, the effect of watershed management measures (educational and biological programs) on ecosystem cultural services from the stakeholder’s point of views of dehchenashak sub-watershed and experts is discussed. According to the purpose, 4 criteria including: relationship and durability of local communities, landscape aesthetic and tourist attraction and education were considered in the form of a questionnaire. Also, Statistical analysis was performed in SPSS software. The results showed that, the effect of watershed management measures on ecosystem cultural services has not been the same and the greatest effect is related to the criteria of education, landscape aesthetic and tourist attraction, relationship and durability of local communities, respectively. In other words, although all the studied indicators of the criteria have a significant correlation with the implemented measures at the level of 0.01, but the indicators of security, migration into village and aesthetic from the stakeholder’s point of views were not accepted. Also based on prioritization, indicator average the trust to experts (8.01) more than stakeholder knowledge awareness indicator (7.98), respect for the rights of others (7.61), improvement of relations (7.21), tourist attraction (7.07), landscape aesthetic (45.45) 6) correct use of resources (6.32), migration outside village (6.20), conflicts and disputes (5.37), security of local communities (5.28) and migration into village (4.70). In other words, among the mentioned indicators, the highest and lowest impacts are related to the indicator of trust to experts and migration into village, respectively.

Hydrological simulation models are valuable tools for examining challenging issues related to watershed management such as the impact of climate change on water resources, the impact of urban planning on floods and droughts. In this study, WetSpa-Python model was developed to simulate daily flow hydrographs at the Arazkouse basin. This is an object-oriented, process-based modular model which has been developed based on the principles of flexible modeling in python. Data inputs included DEM, soil type, land-use, precipitation time series, temperature, and evapotration, which were acquired from nine meteorological stations for a ten-year period (from 2006-07 to 2015-16). Model calibration was performed in a limited manner by assigning rational values to 8 global parameters based on the best fit between the simulated and observed hydrographs. Model performance was tested via the Kling-Gupta index, and obtained 0.6 and 0.52 for the calibration and validation periods, respectively. The results of the water-balance analysis with the model indicated that the outflow of the basin constitutes 13.2 and 18.1% of total precipitation in the calibration and validation periods.

The aim of this research is to predict the effects of cropping pattern changes on the water table level and electrical conductivity of an unconfined aquifer in the Ali-Abad region using a Bayesian Decision Network (BDN) as an integrated approach. A conceptual model framework illustrating the relationship among variables in the system was developed and three management scenarios of crop pattern (current condition, high water demand crops, and low water demand crops) were considered for the study area. Marginal probability, Conditional Probability Tables (CPTs) and total probabilities were characterized using observed data, results of CROPWAT model simulation, and expert knowledge. The Netica software was used to run the Bayesian model and to analyze the sensitivity of the model with two criteria namely reduction of variance and belief variance. The analysis shows that the probability of groundwater depletion occurring for low water requirement crops will be about five per cent less than that in the current condition. The probability of improvement in electrical conductivity for low water requirement crops will be about two per cent greater than that for the current crop pattern. The sensitivity analysis of the Bayesian model shows that the water requirement of crops plays an important role in unconfined aquifer's characteristics. The results demonstrate that the BDNs are capable to help planners for improved management of groundwater resources by predicting and displaying the effects of crop pattern changes on the quantitative and qualitative characteristics of unconfined aquifers in a probabilistic context.

Temporal and spatial distribution of soil moisture is a key variable for hydrological planning. In the research area, increasing soil moisture accelerates the formation of runoff. The purpose of this study is to investigate the L-band potential of the Pulsar 2 sensor from the ALOS satellite in estimating soil surface moisture in order to manage water resources and reduce flood hazards. Samples were taken using random sampling. Simultaneously with obtaining SAR data, weight moisture, surface roughness and plant water content, average radar backscattering coefficients and indices angle were measured on the image. The pre-processing, processing and post-processing stages of SAR data were calculated using SNAP software and extraction of plant and moisture indices in ArcGIS 5.10 environment. Surface roughness was obtained using two angled cameras with 20 images with 10 control points (GCP) for each cluster, then using Agisoft Photo Scan software, dense cloud meshes and meshing were performed to produce DTM. Longitudinal profiles of surface roughness for each cluster were extracted from the Analysts 3D tab in ArcGIS. In order to select the appropriate model in the region, three models were considered in estimating soil surface moisture including Dubois-MLR-WCM models. The results of three models in estimating soil surface moisture in HH polarization in Dubois model with R2 = 0.82 and RMSE = 0.027, MLR model with R2 = 0.71 and RMSE = 0.03 and WCM model with R2 = 0.67 and RMSE, respectively = 0.033 was estimated. The results showed that Dubois model is more suitable for research areas and similar conditions in lands with sparse to medium cover.

The most important indices (or indicator) for soil quality assessment are water infiltration rate into the soil and soil hydraulic conductivity. They play key roles in various issues of watershed management, soil and water conservation and hydrological modeling. By definition, infiltration is the water entry from the thin surface layer of the soil into its profile. Numerous factors such as intrinsic properties of soil, amount of vegetation cover, land use type and soil compaction affect the rate of infiltration. The stakeholders of Aq Qala winter rangelands in northeast of Iran are facing the challenge of water deficit both for drinking water and wateing the livestock during almost the whole grazing period. To solve the problem, they buy and transport water by tractors and tankers. Due to the flat topography of the plain, tractors and tankers commute from many paths without considering the environmental consequences and causes surface layer soil compaction over vast areas. This reduces rainfall infiltration and destrucs vegetation cover of the rangelands at a significant level. This study aims at investigating and quantifying these consequences on the hydraulic properties of topsoil. Infiltration rate was measured by two methods of double cylinder in the field and Lab. with constant head water and disk infiltrometer, measuring saturated hydraulic conductivity by applying constant head of water on undisturbed soil samples contained in metal rings. Using independent t-test, the hydraulic properties of the soil were compared. Samples were taken from the controls and the whecle wheel passage areas. The results showed that there was a significant difference in 95% confidence level between them. In other words, the traffic of water tankers has caused soil compaction and reduced the permeability of the topsoil in the studied rangelands. Result of the study suggests that increasing traffic routes, will create serious ecological consequences in the long term. Also, the analysis of physical and chemical properties of the soil in the area showed that except for the pH parameter, other parameters have a significant difference between the traffic routes and control sites.

In the present study, the effect of management measures on carbon sequestration in areas under management measures and types of land use has been studied.

The crop lands and orchards as controls and terracing and tree saplings activities as the treatment measures were compared in terms of carbon sequestration. Also the effect of management measures on improving land cover and reducing soil erosion from viewpoints of the local stakeholders was carried out using the questionnaire survey.

The results showed that the average of biomass carbon sequestration (ton/ha) in both treatment and control sub- watersheds in dense forest (5.10 and 4.91), low-density (4.98 and 4.80) and degraded forests (4.27, 95 and 95) is more than walnut (3.08 and 2.85) and apple (2.21 and 2.00) orchards, and croplands cultivated with alfalfa (1.55 and 1.50), wheat (1.40 and 1.32), lentil (1.38 and 1.30) and barley (1.26 and 1.19), respectively. Regarding biological practices carried out in the treatment sub- watershed, the average carbon sequestration in walnut orchards (2.72) was higher than pear (1.88) and cherry (1.66) orchards and terraced lands cultivated with alfalfa (1.65), wheat (1.50) and lentil (1.40). Also statistical comparison using t-test between high density, low- density and degraded forests and apple orchards and barley croplands showed no statistically significant difference at 5% level.

Moreover, the local stakeholders believe that the implemented watershed management practices has played a significant role in improving the sub-watershed condition in terms of land cover, soil stabilization and soil erosion reduction.

Land use optimization for proper utilization of land resources has always been one of the main issues in natural resource planning. To avoid the adverse effects of improper land use, management programs should be designed that incorporate land use optimization. In this research, land use optimization has been performed for the Chehelchay watershed, with an area of 25680 hectares in Golestan province, in order to prevent improper land utilization which threatens economic and social sustainability of the watershed. For this purpose, an optimal land use map was created using multi-criteria evaluation method together with economic evaluation of land uses based on the benefit-to-cost ratio. Proposed land uses and protection actions for the Chehelchay watershed include terracing, orchards, agroforestry, forage cultivation, afforestation and riparian forest buffers. To assess land suitability for different uses, several data layers were input and analyzed in Terrset software. Each of the factors (i.e. data layers) was standardized between zero and one. Then, the layers were combined using Multi-Criteria Evaluation (MCE) method to generate fuzzy suitability map for each land use. In the final map, suitability values range between zero (not suitable) and one (perfectly suitable). Also, considering the costs of establishment, maintenance and income of each of the proposed land uses during a 30-year planning horizon, benefit-to-cost ratio was calculated for each land use. The results of the economic evaluations indicated that all of the proposed land uses are profitable. Finally, based on the results of multi-criteria evaluation and economic evaluations, the optimized areas for each proposed land use were determined across the watershed.

Parameter estimation is one of the main tasks in the hydrologic modeling. Parameter values can either be specified logically or blindly calibrated. In distributed physics-based models, it is arguably possible to specify parameters using catchment characteristics, hydrologic knowledge, the physics behind the parameters and how they function in the model. Such logic-based parameter specification is called as parameter allocation. This study tries to practice this modeling approach using the MIKE SHE model and simulate the overland flow in the Ziarat watershed. The model was executed using both approaches for a certain period from 01.23.2013 to 09.21.2014, and for the period from 04.15.2016 to 09.21.2017 as validation. The results of the simulation based on each of the approaches were evaluated by the Nash-Sutcliffe and Kling-Gupta efficiency criteria. Based on these efficiency criteria, the model in the parameter allocation approach has a good performance, and shows consistency in the validation period. Regarding the water balance, the results of the allocation approach are more resoanable and meaningful. Based on this, it can be concluded that spending more time to better understand the watershed charactristics and parameters of the model leads to more acceptable and consistent results that reduces the need for calibration significantly.

The aim of this study is to assess the feasibility of monitoring precipitation, temperature and river stage variables in the Chehl-Chai Watershed with the participation of citizens/stakeholders. Simple and low-cost measurement tools were designed and provided to the local volunteers (two students, three women and one man) and they monitored the variables for five months. The data were recorded on paper forms and/or communicated through cellphones (text messages and social media applications of WhatsApp and Telegram). The citizen-collected data were compared with formal gauging stations using different statistical metrics including correlation coefficient, paired-sample t-test and kappa index. Results revealed that, the difference between the recorded data by the participants and those of gauging stations were not statistically significant. A female citizen with academic education of bachelor’s degree recorded the highest frequency of data that had the highest correlation with the recorded data in the formal precipitation and temperature monitoring stations, while the technical staff man from the Natural Resources Management Office recorded the least frequent data that had the least correlation with the recorded data in the formal monitoring stations. In overall, the promising level of citizens’ performance in monitoring the watershed, suggests that it is really feasible to collect reliable, on-time, and long-term data that can be used to obviate lack of data, particularly in remote mountainous areas and facilitates the decision-making and watersheds management process.

Ancient Iranian civilization flourished in an arid and desertic landscape for thousands of years merely due to special water harvesting and management systems. However, currently the country faces a challenging water resources crisis. Since perception of importance of a subject or technology is key factor in its adoption, this study attempts to inquire into perception of Iranian citizens on the importance and necessity of rainwater harvesting. Therefore, 187 respondents from six regional capital cities were interviewed on their RWH experience, knowledge and opinions on the significance and benefits of RWA. The face-to-face questionnaire administration mode was used for the survey. Results indicates that there is a low level of RWH experience and knowledge among the current generation of Iranian, whereas more than 70 and 40% have no RWH experience and information. Respectively. However, there is a high inclination (80%) towards RWH adoption provided that financial supports shall be available. Since more than 51% of the respondents perceive RWH is highly and very highly necessary in large public and commercial buildings, RWH should start from these buildings. More than half of the respondents believe that rainwater is useful for domestic water supply. The respondents perceive that the reduction of water bills (30% of respondents) and alleviation of water shortage crisis (55% of respondents) are the most important advantages of RWH for private households and general public, respectively. More than one-third of the respondents conceive that main beneficiary of RWH will be agriculture sector