Application of participatory approach in identifying critical sub-watersheds based on flood generation potential in the Cheshmeh-Kileh Watershed, Mazandaran Province

Choosing an optimal decision-making method for watershed management is a problem that has always attracted the attention of researchers, and various methods have been used to achieve this goal. Participatory management is a collaborative process to participate in gathering information, making decisions, and carrying out projects that lead to solving complex social and environmental problems. As it is known, the integrated watershed management approach is a method to achieve sustainable development. Considering the existence of challenges such as floods, one of the useful approaches to solve the existing challenges is to use the approach of integrated watershed management, which is agreed upon by most of the scientific and executive community. The multidimensionality of the watershed system, its integration with socio-economic systems, and the involvement of stakeholder opinions are one of the most important components in the watershed operation and conservation. Therefore, the present study seeks to investigate the necessity of using inter-sectorial management and benefit from the consensus of the main stakeholders using game theory algorithms in 15 sub-watersheds of the Cheshmeh-Kileh Watershed in Tonekabon City. Sehezar and Dohezar rivers are the most important rivers of the Cheshmeh-Kileh Watershed which originate from the Takht-e-Soliman, Alamut, and Khashchal mountain regions. The high capacity of the riverside lands and the limitation of suitable lands in the watershed have caused many agricultural activities to be concentrated along the river, which is severely affected by floods.

In the present study, semi-structured interviews were used to collect information about the flood generation potential. The stakeholders included local stakeholders, policy makers, and the executive organization. Game theory algorithms including the Condorcet algorithm, Borda scoring, and Fallback bargaining were used to prioritize the sub-watersheds. First, the prioritization of each of the three groups was analyzed, and then the results of the consensus of the group and their comparison with the sectional decisions were examined. In this connection, first, the sample size was determined using Cochran and the opinion of the stakeholders was asked regarding the flood generation potential of the sub-watersheds. The number of interviewees in subgroups of local users, policy making institutions, and executive organizations were 75, 13, and 6 respectively. It is worth mentioning that in order to eliminate the effect of the number of interviewees in the final results; the priorities were standardized and dimensionless. In order to prioritize by the stakeholders, first, various maps of sub-watersheds, roads, and even the location of villages were prepared with appropriate quality. Then, they were asked to prioritize the sub-watersheds in terms of flood generation potential based on their personal experiences, local knowledge, technical and policy. In the group of local watershed users and residents, random sampling was done from 21 Cheshmeh-Kileh Watershed villages in Tanekabon city and Mazandaran province.

Based on the study findings, by comparing the two priorities of the stakeholders and the differences between the popular, institutional and policy-making sectors, it can be said that in the Condorcet algorithm, the rate of differences in the voting of local users with policy-making institutions, local users with the executive organization and policy-making institutions with executive organization is 33.33, 66.67, and 80 %, respectively. These differences based on Borda scoring algorithms and Fallback bargaining are 53.33, 66.67, and 93.33 %, respectively. According to the local operators, in all three algorithms based on game theory, Takht-e-Soleiman, Garmarood, and Selajanbar sub-watersheds have the highest flood generation potential in the Sehezar River. Meanwhile, Ketehroud, Holian, and Yandasht sub-watersheds have a low flood generation potential in this river. Regarding the Dohezar River, it can be said that the results of all three algorithms based on the theory of games were almost the same, and Niardareh, Khashchal, and Nosha have the highest potential, and Miankooh, Daryasar, and Golestan-Mohalleh sub-watersheds have the lowest flood generation potential. The second group of interviewees was the executive organization that used the opinions of technical and watershed management experts of the General Department of Natural Resources and Watershed Management of West Mazandaran-Nowshahr. The opinions of this department were different from those of local users. Also, in the Dohezar River, the Niardareh, Khashchal, and Nosha sub-watersheds were given the highest priority, and the Miankooh, Daryasar, and Golestan-Mahalleh sub-watersheds were the lowest priority.

Due to the fact that in the watershed system and in optimal decision-making, there is a wide variety of opinions and differences of opinion, on this basis, the conceptual basis of the application of multi-objective decision-making methods such as game theory algorithms appears. Therefore, the game theory provides an optimal compromise mode based on different opinions, at the same time, the opinions of different interest groups are considered to an acceptable extent without mixing. This basis clearly confirms the necessity of using participatory management. Because when the number of votes and interest groups increases, it becomes difficult to make a decision, and in this regard, by using multi-objective decision-making methods, a general consensus can be reached to identify the optimal pattern of prioritizing sub-watersheds. The first point is that the amount of differences in voters was the same based on two algorithms, Borda and Fallback, which, of course, the Condorcet algorithm has provided more balanced and acceptable values ​​in terms of comparison. Another point was that in all three algorithms, the amount of differences between the two local user groups and the policy-making body was less, and somehow their opinions were close to each other, and they had high differences with the executive organization. In all three algorithms, the amount of disagreement between the two local user groups and the policy-making institution was less, and in a way, their views were close to each other and had high differences with the executive organization. Also, a different prioritization was observed between the final consensus and the inter-sectorial and inter-institutional views. In general, it can be said that using the opinions of stakeholders in the watershed is fundamental for optimal and efficient decision-making and integrated watershed management, and this framework can be used in various issues in the watershed.