Investigating the effects of different land use planning scenarios on the supply of selected ecosystem services (Case study: east of Gilan Province)

Introduction: As concerns about the various effects of land use planning and management are increasing, many researchers are trying to investigate how land use changes affect service processes. Considering the relationship between land use change and ecosystem services, conducting studies on the effects of land use change in planning on the quantity of services provided by ecosystems in order to plan a better location of land use and ensure the sustainable supply of ecosystem services It seems necessary. Therefore, the current research was conducted on this basis and with the aim of comparing the supply of selected ecosystem services in two different scenarios of land use change and in a part of Gilan province.
Materials and methods: In this study, two scenarios were considered for land use planning in the eastern part of Gilan province. The first scenario was based on the historical process of land career change in the study area using the CA-Markov model, and the second scenario was based on land use conservation planning using the Mola model in Idrisi software.In the second step, in order to compare the results of two land use change scenarios on the amount of ecosystem services provided by the study area, the quantification of the ecosystem services of carbon sequestration, soil retention and flood prevention was done using the relevant models in the InVEST software.
Results and discussion: According to the forecast, with the continuation of the past trend until 2020, the amount of carbon storage in 2040 will decrease by approximately 4 million tons compared to 2020. Based on the land use planning carried out in the second scenario, the total amount of carbon stored compared to 2020 has increased by about 9,850,000 tons and compared to the first scenario by about 14 million tons. Also, in the first scenario, the flood volume potential in the basin will reach 148819209 cubic meters. In addition, the ecosystem service index of runoff maintenance will reach 0.36 and its volume will reach 148819209 cubic meters in the entire basin. In the second scenario of the research, the flood volume potential in the studied basin is equal to 141673307.89 cubic meters and it has decreased by approximately 3% compared to 2020. Also, the index of providing this service in the region is equal to 0.38 and its volume is 90229363 cubic meters. The amount of ecosystem service of soil maintenance in the first scenario will be accompanied by a decrease of 528,576 tons compared to 2020. In the second scenario of the research, compared to the first scenario, 765,444 tons have increased, which indicates an increase in the provision of this service by the ecosystem.
Conclusions: The results of this study show that, in general, the trend of changes in the amount of selected services provided by the basin will be decreasing and increasing respectively in the first and second scenarios. This reduction in the first scenario is mainly due to the destruction of forests as the most basic pillar of the desired service production in the studied area and the intense growth of cities as land uses with the lowest level of their supply. And the main reason for the increase in services in the second scenario is to pay attention to the protection point of view in addition to responding to the needs of the residents of the region in determining the area allocated to each user, which shows the process of planning based on sustainable development.