eskandari sub-watershed

Eskandari sub-watershed is one of the most important water supply sources for agriculture, drinking and industry in Isfahan region and province. Therefore, better understanding of the problems within this watershed is crucial for planning and proper management. Moreover, a concerted effort to engage all stakeholders in the integrated management of this watershed is necessary. This research aims to investigate the reasons for the increase of runoff in the years 2011, 2021, and 2031, providing management solutions with the active participation of stakeholders.

First, the height of the runoff was estimated using the curve number method. In this regard, Landsat 5 and 8 satellite images from 2011 and 2021 were used to prepare a land-use map of the Eskandari sub-watershed. Additionally, the prediction of land-use changes in the future (2031) was done using the Markov model. To prepare the curve number map, the combination of the land-use map and hydrological groups was used, and then the runoff height was estimated in the studied years. Following this, through collaborative workshops, stakeholders were asked to create a problems and objectives tree based on the main reasons for the runoff progress in the watershed, consulting with each other. Subsequently, based on the objective tree, the initial list of proposed solutions for the Eskandari sub-watershed was presented. The proposed solutions were then refined, classified, and prioritized by experts. Continuing with the goals of the current research, the most important indicators affecting the current situation of the Eskandari sub-watershed were selected based on the opinions of experts and stakeholders. To model, the multi-criteria decision-making method was used to select solutions and prioritize them. Therefore, initially, the researcher's questionnaire was distributed among stakeholders for scoring the selected solutions according to the assessment criteria. Finally, the results obtained from experts' scoring were prioritized using the TOPSIS method.

The results reveal a significant reduction in natural lands in the region. Consequently, by 2031, rangelands with good and mediocre cover have been completely destroyed, while those with poor cover, irrigation, and rainfed agriculture dominate the region. Based on soil science information, 57.18% of the area is related to hydrological group B with a medium runoff production capacity. Hydrological groups C and D, with percentages of 24.98 and 17.82, respectively, are the next priorities. Following this, by combining the hydrological group map of the watershed with the land-use map in GIS environment, the CN map with curve numbers ranging from 61 to 96 was obtained. Finally, the average infiltration in 2011, 2021, and 2031 was 79.15, 62.82, and 55.12 mm, respectively, while the average runoff in those years was 10.99, 13.15, and 13.38 mm, respectively. According to the results, the losses decrease over time, while the runoff increases. Residential lands and rocky outcrops have the highest amount of runoff production, i.e. 34.38 mm, whereas rangeland with good cover (0.33) has the lowest amount of runoff. In subsequent collaborative workshops, based on the opinions and consensus of stakeholders and experts, improper agriculture was identified as one of the main reasons for increase of runoff in the studied area. Due to a lack of water, insufficient income, and a lack of laws and supervision in the region, watershed farmers and residents are changing land use and cultivating low-yielding lands in an unprincipled manner. Also, in line with the research goals, 11 management solutions and 12 effective indicators (economic, social, and environmental sectors) were identified for the current situation of the watershed. The prioritization results based on the TOPSIS method showed that the solution of creating cover farming to increase surface coverage has been assigned the highest priority.

In this research, efforts have been made to address and mitigate the runoff in the study area. Management solutions have been presented based on the preferences and participation of stakeholders. Therefore, to prevent further runoff in the region, it is suggested to establish institutions tailored to the watershed's situation, considering patterns of cultivation and conservation agriculture, and integrating the cooperation of subordinate institutions and organizations.

In arid and semi-arid regions, water is considered as the most important restrictive factor in drinking, industry and agriculture. In this regard, Zayandehroud River is a prominent example of human and environmental concerns in this climate. Due to the large area of the Zayandeh Roud Watershed and the difficulty of developing and implementing a comprehensive participatory management model for the entire watershed, one of the upstream sub-watersheds of the Zayandeh roud Dam was selected for this study based on the Eskandri sub-watershed. This sub-watershed is important because its outlet leads to Zayandeh roud Dam. In addition, this sub-watershed is one of the most important sources of agricultural water supply, drinkable water, and industry in the region and province of Isfahan. Therefore, this study aims to present management responses regarding the strategy of improving the water resources status of the Eskandari sub-watershed with a logical framework approach.

First, the water resources status of the Eskandari sub-watershed was investigated using the Falkenmark index (FI). This index classifies the regions according to the annual renewable per capita volume (RW) for the provision of water resources. Based on the annual renewable per capita volume per person (m3/person), the FI is asfollows: no stress (FI<1700), stress (1000-1700), water low water (500-1000) and absolute deficiency (FI>500). In the following, in order to achieve the goals of integrated watershed management, the logical framework approach was used. Therefore, by identifying the stakeholders and organization of workshops, a problem tree and objectives for the desired strategy was drawn and a logical framework matrix was prepared based on the tree of objectives. In this research, 30 members from stakeholders (random sampling method) were selected as the sample for the resident questionnaire. In other words, the main, sub-goals, achievements, and activities in order to solve the stated problem were extracted from the objectives tree and classified in the framework of the logical framework matrix. Also, the opinion of 28 experts was also considered as a large group decision-making to prioritize items. The expert group consisted of experts from the Departments of Natural Resources and Watershed Management, Environment, Regional Water, and also scientific members of universities of Yazd and Esfahan, and some members of the village council. In the following, for the assessment, prioritization, and feasibility of doing any management response, first, the criteria and indicators for measuring different responses related to the status of the water resources of the Eskandari sub-watershed were determined. Then, the prioritization and selection of responses were done using the questionnaire method and the Friedman's test.

The results of the research showed that the amount of renewable water per person is 637.60 m3. According to the classification provided by Falkenmark, this shows that the Eskandari sub-watershed is in the low water category. In the following, the results of the logical framework showed that the response of the development of optimal allocation plans for water consumption and regulation of water rights has been assigned the highest score according to the indicators and criteria considered. The responses to the strengthening of supervisory and executive mechanisms and modification of laws and regulations for issuance of exploitation licenses and also, preparation and compilation of integrated water resources management plan were the next priorities in terms of status improvement, respectively. In addition, the results of the significance test indicate a significant effect of managerial responses at five percent 0.05 (P=0.00).

This study aimed to provide optimal management responses regarding the strategy of improving the status of water resources based on the expectations and perceptions of the stakeholders. Therefore, due to the ineffectiveness of the solutions in recent years, the implementation of the integrated management program of the Eskandari sub-watershed through the logical framework approach and the participation of all stakeholders is suggested in order for the principled and sustainable exploitation of water resources. Also, reinforcement of regulatory laws is recommended in order to observe water rights and access more equity in exploitation. In addition, in order to reduce water scarcity and improve the condition of watershed, the policies of the water sector should be enforced in a larger framework and with internal and external cooperation.