The concept of ecosystem services and natural resources has been used to reveal the relationship between human social well-being and ecological sustainability in order to develop the sustainability of natural ecosystems. Recent research shows that combining ecosystem services in management decisions is more suitable for conservation activities and sustainable management of natural ecosystems. The eva‎luation of these services provides appropriate data for a better understanding of the sustainable use of natural resources and the maintenance of these resources for future generations. These researches show that the integration of the ecosystem services approach in land planning and management is considered a major challenge at the world level, and by reviewing the studies conducted in Iran, the lack of research in this field is quite evident; Therefore, it is necessary to address the spatial planning of the use and prioritization of natural areas for protection, considering the value of the ecosystem services, by spatial quantification of ecosystem services and their valuation. This research was done in four main stages. The first step of the work consists of assessment the process of land use/land cover change in the study area using the spatial map of land use in three time periods (past, present and future) which was used as the basis of the study. The second step of the research includes the quantification and mapping of three selected ecosystem services (carbon storage, soil conservation and habitat quality) using the InVEST software package. The third step of research is determining the important areas of ecosystem services. Gi index was used to determine the important areas from the spatial analysis of hot areas in the Arc GIS environment. This index is used to distinguish places with high and low value of ecosystem services. The fourth step of the research was the economic valuation of selected ecosystem services. Finally, the land use/cover map for the years 1991, 2021 and the land use/cover forecast for the year 2051 were prepared. Then a map of selected ecosystem services was produced for the years 1991, 2021 and 2051. The overlapping results of selected ecosystem services hotspots showed that 16.6% of the watershed of Zayandehrud Dam were identified as ecosystem services hotspots. According to the area under the cover of pastures and forests in the study area, the total value of carbon sequestration, soil conservation and habitat quality services in 2021 has a value of 24569528.66 dollars. The supply map of selected ecosystem services (what services and where) are important tools for managers and decision-makers and enable them to identify priority conservation areas due to the supply of more services. The results of estimating the minimum economic value of selected ecosystem services of pastures and forests in the watershed of Zayandehrud Dam indicate the great value of rangelands in the study area. Considering the important position of arid and semi-arid pastures in the central regions of Iran, estimating the economic value of ecosystem services can be the main step in order to determine the place of regulating and habitat services in the country's environmental economy and also to familiarize people and officials with its importance. to be The noteworthy point is that valuing these types of services can end the thinking of considering them free and reduce the reduction and destruction of these resources.

مصطفي تركش اصفهاني , عليرضا موسوي

حميدرضا كريم زاده , سعيد پورمنافي , سيما فاخران اصفهاني

رضا جعفري , سعيد اسلاميان , مرتضي خداقلي