Integration of multi-criteria decision models and recreation opportunity spectrum in the mapping of recreational ecosystem service in Semnan Province

With the rapid development of society, economy and population growth, the impact of human activities on ecosystems is increasing, which has caused the relationship between human well-being and ecosystem to be in the spotlight. To that end, ecosystem services as an essential element for human development and survival emphasizes the benefits that natural ecosystems provide to humans. These services are divided into four categories based on the Millennium Ecosystem Assessment (MEA): provision, regulation, support and cultural. Cultural ecosystem services are important component of ecosystem services that refer to intangible benefits of the human beings from ecosystems and play an essential role in enhancing human well-being. Cultural ecosystem services can include the use of natural resources directly or indirectly.

The present study was conducted with the aim of modeling recreation services in Semnan province. For this purpose, the integration of the analytic hierarchy process (AHP) of one as the multicriteria decision-making methods and the recreation opportunity spectrum (ROS) model was used. In the ROS model, recreational service is estimated based on recreation potential index and accessibility- remoteness index. In the recreation potential index, three elements: the degree of naturalness, the protected regions, and the attractiveness of water bodies, and in the accessibility- remoteness index, the distance from roads and human-made areas were mapped. In this research, Sentinel-2 satellite images were used to prepare the land use map of 2021. Then, using the maximum likelihood algorithm, land use maps were prepared in 18 classes.

According to the land use map, pastures, barren lands and rainfed agriculture have the highest levels of land use in the studied area with 23.57, 22.27 and 17.31% respectively. After that, waterbodies, salt marshes and irrigated agriculture are the dominant land uses with 15.65, 10.98 and 7.84%, respectively. It is worth mentioning that the smallest area of the region is dedicated to wetlands and urban uses. Based on the results, Forest and pasture areas have the highest potential in providing recreation services in the study area. It was also seen that, the third category (low provision- difficult access) and the seventh category (high provision- easy access) respectively have the highest and lowest land surface coverage in terms of the provision of recreational ecosystem services in the province. Overall, the results showed that recreation ecosystem service is affected by various factors caused by human development, especially land cover/use changes. Considering the concentration of both variables of ecosystem service provision and urban and industrial development in the northern half of the province, it is vital to pay attention to the conflicts between the development and management of ecosystem services. If this is ignored, in addition to intensifying the instability of development, the destruction of natural assets of the province, especially forests and pastures, which are the main source of provision of various ecosystem services such as recreation, will intensify.

In general, the results indicate that most of the places in the province have a medium to low ability to provide recreation services. Considering that recreational potential is important for the well-being of urban populations, increasing urban parks and green infrastructure areas is a useful way to improve the quality of the recreational experience. Therefore, urban development strategies should increasingly aim to strengthen the natural and artificial network of green space, diversity of plant compositions and biomass structure, and proper management of green space. This is necessary for the design of green space with regard to maximizing ecosystem services in Semnan province.