نشریه مدیریت جامع حوزه های آبخیز
سال سوم شماره 1 (پیاپی 7، بهار 1402)

Ecotourism is a kind of tourism in which visitors want to visit some unique and attractive natural landscapes and enjoy observing ecotourism destinations which are suitable for ecotourism due to their attractive landscapes, biodiversity, and traditional agricultural productions. Such phenomena include endangered plant species, wildlife, mountains, waterfalls, caves, rivers, wetlands, beaches, gardens, local cultures, and so on. The objectives of ecotourism are the protection and sustainable exploitation of natural attractions, improving the livelihood of the local stakeholders, and the satisfaction and well-being of tourists. Therefore, the degradation of these valuable and unique natural phenomena not only makes the ecosystems fragile and imposes consequences such as floods, erosion, dust and desertification, but also deprives the society of the employment opportunities brought about by ecotourism. Nevertheless, due to the lack of welfare infrastructure, improper management and negligence of related departments, cutrrent tourism leads to the destruction of natural resources. The purpose of this research was to identify areas prone to ecotourism and its feasibility based on existing capabilities and required infrastructure in Kermanshah province.

Kermanshah province (west of Iran) has beautiful, diverse and unique ecotourism attractions, which are actually a reflection of its geological, topographic, soil, climatic, vegetation and geographical conditions. This research was carried out in three stages, which includes the collection of data and information on natural phenomena capable of ecotourism, interviewing relevant experts and experienced inhabitants about the potential and capabilities of ecotourism (within a designed questionnaire) at the local scale as well as addressing the destruction factors and infrastructures required for the sustainable development of ecotourism. Validity of the content of the questionnaire was obtained based on Cronbach's alpha coefficient which obtained between 0.75 and 0.93. The questions respondents focused on centered around infrastructure and facilities for the development of ecotourism, threatening factors and proper management for its sustainability at the local scale in Kermanshah province, Iran.

The results indicated that there are 55 sites that are suitable for ecotourism industry in Kermanshah province, Iran. These ecotourism destinations include mountain highlands, forest park, forest reserve, cave, river, spring, tourist village (with traditional handicrafts, livestock and garden products, herbal plants), nomadic lifestyle, landslide (2016), Bazidraz mountain (relics of Iraq war) and urban gardens were detected in 55 places in Kermanshah province. Due to the phenomenon of dissolution, high altitude above sea level and sufficient rainfall, most of the mountains of the province have diverse faces such as valleys, ravines, rocks, rocky outcrops, springs and caves with unique biological diversity that are suitable for climbing, forest survey, skiing, temporary accommodation, recreation and scientific studies (botany, geography) on a local, provincial, national and global scale. Some cases are also suitable for forest reserves due to having rare or endangered plant species or having a special habitat for the establishment of extinct species. In addition, areas of rivers, pastures, traditional ways of life and animal husbandry activities and livestock products of nomads, villages with tourism destinations and handicrafts are also important in the development of ecotourism in this province.Furthermore, the results of the interview with experts showed that the security of the region for tourists, outstanding cultural features and local traditions of villagers and nomads along with natural tourist attractions were the most important factors attracting ecotourism in Kermanshah province. Also, the most important threats to ecotourism include lack of funds to equip surveillance forces (vehicles, fire suppression equipment, etc.), lack of planning to provide infrastructure facilities for ecotourism development, excessive livestock grazing, change of national land use, cultural barriers, and abandonment, garbage and plastic waste in the environment. Finally, the most important factors affecting the sustainability of ecotourism include preventing the destruction of ecotourism areas with the participation of local residents, private sector investment, preserving and reviving the traditions and historical identity of rural and nomadic life, training professional skills to guides and personnel related to ecotourism, the establishment of accommodation and reception facilities in line with international tourism standards.

Based on the results of this survey, there are 11 types of ecotourism in Kermanshah province, which are suitable for the sustainability of ecotourism and natural resources due to favorable geological, topographical, climatic and vegetation conditions. However, the current trend of nature tourism, which is effective without payment and supervision, destroys ecotourism destinations in various ways, including soil compaction, crushing plants, cutting of bush and branches, arson fire, and plastic waste. This improper tourism not only does not generate income for the local inhabitants, but also damages their farms and living environment. Numerous road constructions and land use changes and factors like this have an increasing trend that is almost irreversible. By providing the necessary facilities for the comprehensive management of ecotourism in Kermanshah province, the sustainability of natural resources, the satisfaction of tourists, and the creation of employment for local residents will be realized.

Detecting the potential of groundwater resources is one of the most important methods of water exploitation management to deal with water shortage, which is inevitable due to the growing need for water in the country. The first step in managing groundwater resources is to recognize the potential of groundwater. Fuzzy-Analytic Hierarchy Process (AHP) is also recognized as an important tool in decision-making about natural resources management, especially water resources. Bam-Narmashir plain, in Kerman province, is one of the most important plains of the country. This plain plays a very important role in the region in terms of supplying the water resources needed by agriculture, industry and drinking parts.

In this study, AHP-fuzzy model and GIS were used to identify suitable areas for potential groundwater resources in Bam-Narmashir plain. Criteria such as rainfall, temperature, geographical direction, slope, land use, vegetation cover, distance from the road, distance from the river, distance from the fault, distance from the city and village, distance from wells and springs, soil texture and the permeability of the formation were selected for decision making and the weight of each of them was calculated and prioritized using AHP model. Then, the desired layers were fuzzy and indicator maps were prepared using Arc GIS software. Then, the groundwater potential map was prepared. Finally, the ROC curve was used to validate the groundwater potential map in the region.

The result of ROC curve indicated the high accuracy of Fuzzy-AHP method in preparing the groundwater potential map in the study area. The results were consistent with the results of researchers such as Rezaei Moghadam et al. (2017) and Faraji Sabokbar et al. (2011). Also, the results showed that the regions with geological sub-criteria have the highest weight of 0.614 and the climatic sub-criteria have the lowest weight of 0.117. The value of inconsistency ratio was 0.07, which is smaller than 0.1, and it indicates consistency in the opinions and judgments of research decision-makers. Finally, the results showed that about 7.77% of the total area of the plain, equivalent to 755.54 square kilometers, is suitable for the implementation of underground water resources potential detection systems. Also, 1.57, 31.71, 58.98 and 7% of plain lands have very weak, weak, medium, and high potential for finding the potential of underground water resources, respectively.The results showed a sparse distribution of suitable areas for groundwater potential in Bam-Narmashir plain, which is compatible with the results of Sekar and Randir (2007), who stated that the groundwater recharge potential at the scale of the watershed has non-uniform spatial distribution. The results showed that in the northern and western part of the plain, where the soil is mostly low capacity for groundwater potential and infiltration, which is in line with the results of Akbarpour et al. (2015), who stated in west and north-west of Birjand basin, the soil has a low capacity for groundwater penetration due to the low depth of the soil and high slope.

In recent years, the use of geographic information system (GIS) and its combination with multi-criteria and decision-making methods to obtain more accurate results have increased and played a key role in studies of the finding potential of groundwater resources. Even though it is very difficult and complicated to accurately identify suitable places for the potential of underground water resources, this study showed that the use of GIS makes it possible to identify these suitable places with minimal facilities, which is consistent with the findings of Khairkhah et al. (2013). Overall, according to the results of this study, about 7% of the region has high groundwater potential. Therefore, it is necessary to adopt scenarios to reduce the over-exploitation of groundwater and to apply the measures to improve the irrigation systems, the methods to reduce evaporation and improve the cultivation system.

Nowadays, the approach of integrated watershed management (IWM) has been widely accepted as a reference and reliable model by scientific experts, executive managers, policymakers, and planners in the country. From the perspective of many experts and professionals in natural resources and environment, the land area of Iran is surrounded by a range of natural, climatic, and social hazards related to watershed areas. In conditions where each of these hazards alone can lead to environmental, economic, and social crises, a critical analysis of IWM as the most accepted management unit in nature is essential. Despite the importance of this reference model for planning and organizing watershed areas, this approach is often subject to personal preferences due to the lack of a comprehensive and widely accepted definition at the macro level, which results in managers and planners not being responsive. Moreover, watershed management plans and comprehensive management of watershed areas in Iran face various challenges and have not been successful despite the allocation of considerable resources. Therefore, it is necessary to address the ambiguities and challenges of the integrated management approach in order to achieve a coherent and comprehensive management in watershed areas. In this regard, the present study focuses on a critical analysis of the hidden challenges in the approach of IWM and provides policy recommendations and practical suggestions for IWM in Iran.

In this study, two tasks were performed to examine and explain the comprehensiveness dimensions. In the first stage, resources related to studies on natural resources and watershed management in the country were reviewed. In this stage, the targeted resources were examined using the term "integrated" and the words, terms, and concepts associated with this term. The result of this review was the determination and identification of six keywords and concepts related to the term "integrated". In the next stage, these six factors and keywords were used as six diagnostic and identification codes for examining watershed management plans and IWM. The focus was on determining the presence or absence of these keywords and terms in the implemented watershed management plans. The objective was to determine whether these six key words and theoretical concepts identified in the first stage have been employed in the practical implementation of the IWM plans. This was accomplished through content analysis of implemented watershed management plans in various regions of the country. In each of the implemented plans, the type and extent of utilization, or, in other words, the level of attention given to the mentioned six factors, were examined and analyzed.

In this study, corresponding to the six dimensions of comprehensiveness in the concept of IWM in Iran, six policy recommendations and implementation proposals have been presented. These policy recommendations and implementation proposals encompass a combination of environmental, economic, social, and cultural factors, as gaps in these factors will hinder the integrated management of elements. This research suggests that the executive responsibility for integrated management should be entrusted to the Natural Resources and Watershed Management Organization of the country in coordination with other relevant organizations. This organization, if legal barriers are removed and policy-making streams are aligned, will be able to fulfill its main intrinsic duty, which is the management of the country's watersheds. Regarding the components of ecosystem stakeholders, this study emphasizes that the stakeholders should include all ecosystem stakeholders since any form of anthropocentrism jeopardizes the sustainability of ecosystems. In terms of the dimension of interconnectedness of natural boundaries, the results of this study emphasize the importance of interconnectedness in terms of perspectives, planning, and policy-making. In other words, political boundaries at the county, provincial, and international levels pose increasing challenges to IWM. Therefore, the basis for planning should be the natural boundaries of watersheds. Hence, bridging the gaps and achieving interconnectedness in terms of intra-county and intra-provincial boundaries can be achieved through organizational coherence and defining the responsibilities of organizations based on the natural boundaries of watersheds. As for international boundaries, it requires strengthening diplomacy and reaching regional agreements and treaties. Regarding the elements that should be considered in the comprehensive management approach by planners and executive managers, it can be stated that these elements should include all the components present in ecosystems, including water, soil, and vegetation cover.

The findings of this study indicate the possibility of employing integrated, cohesive, and coordinated management in the natural environments of Iran as a suitable, precise, scientific, and systematic guideline. The recommendations and proposals of this research can lead to interconnectedness, comprehensive perspectives, organizational coherence, coordination among decision-making bodies, enhancement of policy and legal effectiveness, community satisfaction, alignment of activities between planners and watershed residents, and ultimately, improvement in social responsibility and widespread participation of stakeholders in watershed management. Implementing the recommendations provided in this study in future plans and projects can contribute to improving the environmental conditions of watershed inhabitants and ensuring the sustainability of natural ecosystems by addressing the existing challenges.

One of the key issues in river engineering is analyzing the flow properties at the intersection of natural rivers and canals. The flow of the side channel moves away from the intersection of the two channels as a result of the exchange of input force from the side channel with the main flow after coming into contact with it. One of the most evident properties of the flow in these sections is the development of a revolving region with low pressure and even negative pressure close to the inner wall of the side channel. One advantage of the whirling flow in this low-pressure region is that it gives the flow enough space to sediment, but it also increases flow speed near the channel's bottom and outside wall by lowering the intersectional area of the flow. One of the most crucial considerations in the design of these intersections is minimizing sedimentation in the rotating region and scouring in the area above the shear plane.

The channel (flume) created in the laboratory based on Weber et al., (2001) model, was employed in the current investigation to confirm the validity and examine other study objectives. The main channel is 21.95 meters long, while the side channel, which is at a 90-degree angle to the main channel, is 3.66 meters long. The total downstream discharge is approximately 0.17 m3/s, with the upstream velocities of the main channel being 0.166 m/s and the side channel being 0.5 m/s. In both channels, the flow depth and width are 0.91 meters and 0.296 meters, respectively. In this study, 6 various models' angles of intersection between the main and side channels, inlet flow velocity, intersectional area, and side channel length have been examined. Models 2 and 3 have intersection angles of 60 and 30 degrees, respectively, and share the rest of their attributes with the fundamental model, or model number 1. Model 1 is the same as Weber's experimental model. The length of the side channel in model 4 is different from model 1. The only difference between model 6 and the basic model is the side channel intake speed.

Analyzing the intersection angle The angle between the main channel and the side channel is investigated in this section of the findings. Models 1, 2, and 3 are assessed using the intersection angles of 90, 60, and 30 degrees, respectively. In some studies, the impact of the intersection angle has been examined, but in this study, three-dimensional investigation in transverse and longitudinal sections as well as the plan of the intersection is discussed, as can be observed from the literature review.Considering three models with intersection angles of 90, 60, and 30 degrees, the kinetic energy contours at the channel's middle height can be obtained for each model. The channel with a 30-degree intersection angle (model 3) has the maximum kinetic energy in the flow. The channel with a 60-degree intersection has the minimum kinetic energy. As a result of the maximum deviation of the flow in the main channel caused by the flow of the side channel, the channel with a 90-degree intersection also has the maximum kinetic energy near the wall in front of the side channel. Examining the side channel length In model 1, the side channel is 3.66 meters long, whereas in model 4, it is 5.52 meters long. This study aims to determine how changing the side channel's length affects the flow pattern where two channels intersect. The kinetic energy contours were obtained for two states of the channel length, which are known to extend the lateral channel, increase the energy of the flow after the intersection, and shorten the length of the high-kinetic energy zone. When compared to model 1 with a shorter length of the side channel, the width of the flow separation zone is reduced by approximately 20%, which results in less flow sedimentation. Figure 12 illustrates the rotating zones in the flow separation area. The flow separation region's length is essentially unchanged. Studying the intersection of the lateral channel After determining the lateral channel's length, its width and, consequently, its intersectional area should be evaluated. This section compares model 1 width of 0.91 meters to model 5 width of 1.40 meters. One of the most recent topics related to the intersection of the main and side channels is examining the intersection of the side channel. In model 5, the side channel's flow rate has also increased due to an increase in the width or intersection of the channel. The flow rate through the intersection and the momentum of the flow from the side channel and the main channel increase when the side channel flow rate rises. The findings indicate that when flow width and side channel flow rise, energy increases after the inlet. Investigating the value of inlet speed in the side channel Unlike the preceding sections, which were all concerned with the channel geometry, the inlet velocity in the side channel is one of the hydraulic parameters of the flow. In this section, models 1 and 6 with inlet velocities of the side channel of 0.5 and 0.75 m/s are evaluated. According to the modeling, the flow is somewhat horst before and immediately on the intersection of the flow level, but it undergoes a substantial prolapse just after the intersection. Model 6 has a larger volume and height of flow, but a smaller and softer prolapse after the intersection.

Some hydraulic and geometric properties of the intersection of channels have been examined using Flow-3D software. The RNG turbulence model was used for three-dimensional modeling. Some of the results are listed below. The flow is uniform upstream of the main and minor channels and only slightly becomes horst at the intersection. The analysis of the lengthening of the side channel revealed a 20% reduction in the separation zone's width and a considerable reduction in the kinetic energy at the intersection. The input flow rate of this channel to the intersection increases with the speed and width of the side channel, which accounts for the local drop in the width of the main channel flow.

Nowadays, the effects of acid rains in different regions of the world have been considered by most researchers as well as politicians around the world, such that acid rain has new dimensions and has become one of the key words in scientific circles around the world.

The present study investigated the effects of acid rain in different regions of the world and on soil, ranges and forests, seas and lakes and rivers, humans, buildings and structures as well as transportation industry and agricultural products according to national and international scientific documents.

The results showed that acid rain, which occurs naturally due to the combination of water and carbon dioxide, leads to the creation of a weak acid called carbonic acid, which is extremely useful for nature and does not cause any destructive effects on the environment and humans. However, what has disturbed this natural trend in recent decades is the unscrupulous and unthinking interference of human beings, which has caused natural acid rain to become artificial acid rain and has very destructive and dangerous effects for humans and the entire planet. The results also showed that soils around the world, despite the buffering state that is created and have an important defense device called calcium carbonate, are still severely affected by acid rains and there are significant changes in soil properties as well as accelerating its erodibility. Other categories such as ranges and forests, agricultural products, surface and non-surface waters, humans, buildings and structures, transportation, and wildlife do not usually have a good defense against the destruction caused by acid rain and can be far more effective. The results also showed that the biggest victim of acid rain is human, which appears to be weaker than other categories and has more influence than acid rain.

Due to the risks of acid rain around the world, various studies have been conducted on soil, vegetation and forests, agricultural products and surface and subsurface waters, but they are usually not comprehensive throughout the world. However, studies on the role of acid rain in various buildings and structures, transportation industry and onshore and marine wildlife as well as humans are very few. The strong recommendation of this research to researchers and politicians is that acid rain can even change civilizations, so it should be taken extraordinarily seriously, just as in the past water shortages have changed civilizations. In the future, acid rain and changes in water quality can transform civilizations around the world. Furthermore, considering that there are several methods around the world in all different sectors to deal with acid rain, but there is a pressing need to establish an important and comprehensive law to coordinate researchers and politicians and make the methods of dealing with acid rain more efficient, so it is recommended that the comprehensive law against acid rain be passed and implemented in Iran as soon as possible.

Today, soil erosion has become one of the biggest problems in the world, especially in arid and semi-arid areas, which affects environmental, agricultural and food security issues. On the other hand, the growth and development of human activities along with land use change and resource destruction are among the factors affecting the intensity of erosion. Soil erosion in Iran has intensified due to the destruction of natural resources in recent years, and land use changes have played a significant role in this process. However, until now, preventive approaches based on soil erosion hazard assessment to adopt correct management measures have received less attention, which is mostly due to the lack of necessary statistics and information in the basins. Therefore, in any case, it is necessary to identify the areas prone to erosion and sediment production in the internal sub-basins of Iran, which lead to the loss of thousands of tons of fertile soil every year. To achieve this objective, models have been presented, each of which has strengths and weaknesses. By organizing the information related to the decision-making process and simulating the factors affecting the decision, as well as by simplifying the relationships in nature, the models lead to the understanding natural systems. Models are tools that are used in combination with many other assessment methods, so it can be said that modeling is the best option for the initial assessment of watersheds without statistics or with limited statistics. Therefore, the present study was conducted with the aim of investigating the hazard and identifying the areas sensitivity to soil erosion in the sub-basin of the Chehelgazi watershed of Kurdistan province using the Fargas model.

Chehelgazi sub-basin as one of the sub-basins of Qeshlaq dam is located in Sanandaj province. Considering the natural and weather conditions, it is considered representative of mountainous areas (27,233 hectares and equipped with a hydrometric station). The average height of the mentioned sub-basin is about 2200 meters above the sea level, and also the average annual rainfall in this sub-basin is 294.2 mm, the area of pastures is 23465 and the total of irrigated and rainfed agriculture is 3768 hectares. Fagas model was used in order to investigate the hazard and identify the areas sensitive to soil erosion in the mentioned sub-basin. In determining the hazard of erosion, the Fargas model considers two factors of erodibility of rocks and drainage density in each rock unit. In this research, by using maps of rock units, drainage density and scoring tables related to the model, a soil erosion hazard map of the basin was prepared. In the first step, the rock units of the basin were determined using the geological map, and based on the model guide, the rock resistance to erosion was evaluated. In the second step, the drainage network map of the studied basin was prepared and integrated with the stone unit map, and after integration, the drainage density of each stone unit was determined and based on the model valuation guide, the drainage density of each stone unit was valued. Finally, the erodibility hazard map of the basin was prepared in five categories (low to very severe) by multiplying the value number of rock erosion resistance and drainage density in each rock unit.

The results of the Fargas model analysis showed that 0.48, 36.15, 15.35 and 48% of the sub-basin are in low, medium, severe and very severe erosion hazard, respectively. In other words, 63.35% of the sub-basin is in a state of severe and very severe erosion hazard. Comparing the results of the model with various studies in the basin and other similar basins showed that the Fargas model estimates the erosion hazard more than the actual value, which can be caused by the valuation of rock units. However, the existence of shale and its high sensitivity to erosion in the basin and the confirmation of the model in determining its erosion hazard can be a confirmation of the efficiency of the model.

The results of the present study indicate the hazard of high erodibility of the sub-basin. Because of the the sub-basin's position in the water supply of Qeshlaq Dam, it is suggested, while examining other quantitative and qualitative models and their results, to provide evaluation and planning models, to make management decisions, and to promote, train, and implement useful projects related to reducing the rate of displacement and loss of the soil at the basin level. Because in order to increase the life and efficiency of dams, the entry of sediment into the dam should be as low as possible to be a small step towards reducing the rate of soil erosion and wastage. However, according to the results of the model, it can be observed that the studied area is under severe hazard of soil erosion, and these results are useful for researchers and planners to control erosion; but due to the limited number of studies in the region, other studies should be conducted in the region for more certainty.