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Hossein Varjavand Naseri, Asghar Tahmasbi, Hasan Darabi, Ahmadreza Yavari, Mohammadjavad Amiri, Gholamreza Nabi Bid Hendi,
Volume 7, Issue 4 (2-2021)
Abstract

   Extended Abstract:
The increasing challenge of water in many regions of the country is rooted in inappropriate governance of water resources at the basin levels. Investigating the interactions of different stakeholders and institutional arrangement affecting it is one of the key elements of governance system. The most important obstacle to achieving the optimal governance model of water resources in developing countries is the unknown path from governmental management, to good governance. The analysis of stakeholders and influential entities on their interactions is considered as one of the important pillars of governance assessment frameworks.
Accordingly, the purpose of this study is to evaluate the water resources of Zayandeh roud basin from the perspective of interactions between actors and formal institutions affecting their interactions. In this regard, it is attempted to answer two main questions: firstly, what is the organizational structure in management of Zayandeh roud?, Second, how far are the organizations’ policies and programs involved in the management of the watershed ?
In this study, Isfahan, Chaharmahal - bakhtiari , Khuzestan and Yazd which are related to the river basin issues, were selected for social network analysis. Organizations and governmental and non- governmental institutions related to the process of sustainable management were questioned. In this regard, according to the numerous studies conducted in the field of Zayandeh roud and Gavkhoni wetland , the number of organizations and related institutions were identified. Then, the network matrix of actors’ policy and collaboration was formed and centrality indices of input and output grades and betweenness centrality indices were measured through Ucinet software.
There are a wide range of active actors in management of Zayandeh roud river basin, each in an attempt to obtain more water resources from this river. As mentioned in the conceptual framework of the research, two key aspects are investigated. Key stakeholders analysis and their role in water resource management and review of actors ' policies in water resource management in two dimensions of belief in changing policies, and the need to change policy from the viewpoint of other actors. Accordingly, the research findings are presented in the following parts.
  • decision making and facilitating information flow
  • Power and control of actors in the network of organizational collaboration
  • Co - ordination role in the enterprise - cooperative network
The findings of this research show that in the dimension of capacity and flow of information watershed management, Regional water organization in Isfahan province and in the next rank of water resources management, Zayandeh roud coordination council and Isfahan provincial governor are organizations that have high output degree and can play a key role in information flow. In other words, information that is necessary for the actors and other organizations is better flowed by these organizations.
In terms of supervision on the network of interactions and control over other actors in the basin, which was measured with the degree of centrality of input, Isfahan parliament representatives in the first and the agriculture jihad of Isfahan province gained the highest rank respectively. After these organizations which are mainly government and dependent entities, non - governmental organizations of three other provinces have the lowest rank in terms of ability to control the network. The lower power of NGOs in the social network of the organization indicates a low planning system for the management of the watershed. Comparative studies in the river basin show that the feature of the extent and diversity in the social - ecological system of a watershed among several distinct political areas can reveal the importance of the position of organizations that have a bargaining power in the watershed management network.
Betweenness centrality index in information exchange network has a fundamental role. The actors with the intermediary rate and high control power among the organizational stakeholders are the same organizational entrepreneurs who have an important role in establishing relationships and increasing interactions among other actors. If the actors with high degree of mediation are removed from the network, information exchange in the network will be disrupted.
It is obvious that without knowing these corporate entrepreneurs or in other words, actors with high mediation ability in the exchange information network, any activity in the direction of comprehensive management of land and sustainable development will be associated with time and cost. In connection with the task of coordination in watershed management, the Jihad of agriculture organization, department of environment and water room committee of Isfahan have obtained the highest degree of betweenness centrality which seems to be a suitable place due to their organizational functions. In this regard, attention and reinforcement of organizations such as NGOs and parliament representatives of three other provinces and provincial governor of these three provinces with low degree of betweenness centrality can be suggested. The lack of such interaction is undoubtedly one of the challenges facing sustainable management of the region. According to the results of other studies, it can be said that to achieve sustainable and integrated management of land and preservation of natural areas, it is necessary to study the pattern of relationship between organizational stakeholders.
The results show that the Regional water organization of Isfahan province and the Zayandeh roud coordination council have a higher position in decision making and information flow. On the other hand, the high performers of water resources such as Iran’s water resources management company and the Zayandeh roud coordinating council and in the next level, Regional water organization, the provincial governor and the parliament representatives of Isfahan are the best critics of the watershed governance. In contrast policies of jihad agricultural organization, farmers and Regional water organization of Isfahan have been criticized by other actors.

Seyed Ali Badri, Siamak Tahmasbi, Bahram Hajari,
Volume 8, Issue 3 (12-2021)
Abstract

Investigation of Temperature and Precipitation Changes in the Seymarreh Basin by Using CMIP5 Series Climate Models
 
Abstract
Panel reports on climate change suggest that climate change around the world is most likely due to human factors. Temperature and precipitation are two important parameters in the climate of a region whose variations and fluctuations affect different areas such as agriculture, energy, tourism and so on. Seymareh basin is one of the most significant sub-basins of Karkheh. The purpose of this study is to predict the impact of climate change on precipitation and temperature of the Seymareh Basin in 2021-2040 period. These effects were analyzed at selected stations with uncertainties related to atmospheric general circulation models (GCMs) of CMIP5 models under two scenarios of RCP45 and RCP85 through LARS-WG statistical model. Then the uncertainties of the models and scenarios were investigated by comparing the monthly outputs of the models by the coefficients of determination coefficient (R2) in the forthcoming period (2021-2040) with the base period (1980–2010). The root mean square error (RMSE) calculations presented the best model and scenarios for generating future temperature and precipitation data.            
The Seymareh catchment is the largest and the main Karkheh sub-basin that covers parts of Kermanshah, Lorestan and Ilam provinces. The length of the largest river at the basin level to the site of the Seymareh Reservoir Dam is approximately 475 km, and the area of the basin is 26,700 km2. Geographic coordinates of the basin are from 33° 16 ́ 03 ̋to 34°59 ́ 29 ̋north latitudes and 46°6 ́9 ̋to ̋ 5 ́ 0 ° 49 Eastern longitudes, minimum basin height 698 m at the dam outlet and its maximum height 3,638 m. It is on the western highlands of Borujerd.
The information used in this study was obtained from the Meteorological Organization of the country. For this study, three synoptic stations of Kermanshah, Hamadan and Khorramabad, which had the highest statistical records and had appropriate distribution at basin level, were used. These data included daily and monthly temperature and precipitation information, and sunshine hours.
The LARS-WG fine-scale exponential model was proposed by Rasko et al., Semnoff and Barrow (1981). We used daily data at stations under current and future weather conditions. In order to select the best GCM model from the models mentioned above, minimum temperature, maximum temperature, precipitation and sunshine data were entered daily in the base period (1980–2010) and data were generated for five models under two scenarios of RCP45 and RCP85 for the period 2040–2021. The data were generated in 100 random series and the mean of required variables (minimum temperature, maximum temperature and rainfall) were extracted monthly in the period 2021-2040. Then, root mean square error (RMSE) and determination coefficient (R2) were used to evaluate the performance of the models and compare the results.
To ensure the models' ability to generate data in the coming period, computational data from the model and observational data at the stations under study should have been compared. The capability of the LARS-WG model in modeling the minimum temperature, maximum temperature, and radiation at the stations under study was completely consistent with the observed data. The model's ability to exemplify rainfall was also acceptable, however the highest modeling error was related to March rainfall.
By comparing the observed and produced data including monthly average precipitation, minimum and maximum temperatures through five mentioned models with their indices, the best model and scenario for future fabrication were determined. The results of this comparison showed that among the available models, HADGEM2-ES model under RCP 4.5 scenario had the best result for precipitation and HADGEM2-ES under RCP 8.5 scenario predicted the best result for maximum temperature. Determining the best model, precipitation data, minimum temperature and maximum temperature produced in the selected models and scenarios were analyzed to investigate the climate change temperature and precipitation for the future period.
The results of this study indicated that due to the wide range of output variations of different models and scenarios, by not taking into account the uncertainties of the models and scenarios can have a great impact on the results of the studies. It was also found in this study that the LARS-WG exponential model was capable of modeling precipitation data and baseline temperature in the study area, so that the radiation data, minimum and maximum temperatures were completely consistent with the data.
The observations are consistent and the models' ability to predict rainfall is very good and acceptable manner. In investigating the uncertainties caused by atmospheric general circulation models and existing scenarios, the best model to predict precipitation in the study area is HADGEM2-ES model under RCP 8.5 scenario, the best model for temperature estimation model HADGEM2-ES under RCP scenario No. 4.5.
The overall results of this study revealed that the average precipitation in the basin will decrease by 4.5% on average, while the minimum temperature will be 1.5° C and the maximum temperature will be 2.17° C. The highest increase will be due to the warmer months of the year. Notable are the disruptions of rainfall distribution and the high temperatures will have significantly negative consequences than rainfall reduction.
 
  • : Climate Change, Climate Scenarios, Uncertainty, LARS-WG, Seymareh.
 
 

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