Water resource management has numerous environmental challenges, especially in aquatic ecosystems such as rivers due to the heterogeneous distribution of surface water resources, among other diverse impacting factors. In Iran (one of the countries of the Middle-East), population growth, development of urban communities and development of agricultural and industrial activities provide additional impacts on the functioning of aquatic ecosystems. The United Nations declared the third decade of this century (2021–2030) as the decade of ecosystem restoration. In this study, we have selected the Zayandehroud River as a case study and then evaluated the pathology of existing statuses. Strategies and approaches were studied and analyzed including the need to utilize integrated water resources management (IWRM), approaches for dealing with drought conditions, payment of water rights and dam alternatives, and the need for ecological landscape studies.

Then, strategies and approaches appropriate from the perspective of restoration were identified, including the techniques used, and the experiences of different countries. The analysis showed that similar regions of Iran in the Middle-East need to change the paradigm of "nature control" to the paradigm of "nature management" and reduce reliance on structural and technological solutions in water resources management.

Iran is one of the driest countries in the world with an average rainfall of 240 mm per year and has a heterogeneous spatial distribution. 1% of Iran's area has more than 1000 mm of rainfall, while 28% of the country has less than 100 mm of annual rainfall. Approximately 70% is evaporated of the 415 billion cubic meters of annual precipitation in Iran1. According to existing definitions, regions with less than 1000 m3 of water available per person per year have unsuitable conations. The continuation of the current trend of population growth, lack of proper water demand management and reform of water consumption patterns will lead to Iran face a serious water crisis in the near future. By 2050 Iran is expected to be among the water-scarce countries.

Drought and changes hydrological conditions will have significant effects on the ecological characteristics and biological communities of rivers. The direct effects of drought include reduced water levels and reduced access to habitat for aquatic animals. Its indirect effects include increased inter-species competition and changes in existing natural food resources11,12. The gradual drying of rivers over time provides an opportunity for the behavioral adaptations of aquatic organisms.