Document Type : Original Article
Department of Agronomy, International Campus Ferdowsi University of Mashhad, Mashhad, Iran
Department of Agronomy, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
Department of Economy, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran
Urbanization creates significant changes in global ecosystems (2), on the other hand, urban agroecosystems prepare valuable and demandable ecosystem services in human society(3). Understanding these services and keeping them into account is necessary for urban management of both current society and future generation(2,3).
Materials and methods:
So this study was conducted in 2015 in Mashhad parks. To evaluate services like carbon sequestration, oxygen production and pollutants removal, plants data in plots was entered in itree software and their values was calculate with international gases tax and also social values. In order to valuate services such as diversity in landscapes, water storage, soil formation, biologic pest control and cultural services, some questionnaire with choice experiment method was designed and the average of willingness to pay of landscape experts was analyzed.
Results and discussion:
The urban forest of Mashhad has a tree cover of 41.6 percent. The three most common species were Acer negundo (17.4%), Platanus orientalis (15.6%) and Robinia pseudoacacia (11.7%). Percent of young trees were more than others and so ecosystem services of parks is mostly from younger trees. Population of exotic tree species was more than native ones. Most exotic tree species had origin from North America (44.1%) and 15.9% with Asian origin. The gross carbon sequestration of trees was 1.0387 ton per hectare per year. Most of this amount belonged to Platanus orientalis. Oxygen production was 0.24656 and pollutants removal was 0.041 ton/ha/year. Carbon storage per hectare was 22.769 ton.Results showed that the value of regulatory services like (carbon sequestration, oxygen production and pollutant removal) in Mashhad parks was 4 million Rials in a year per hectare and carbon storage was 61 million Rials per hectare. As the atmosphere is a huge source of oxygen, this gas was not calculated in the monitory valuation. Amount of oxygen production in all parks that was 290 ton,can prepare needs of 115 persons. Species richness was 38 with 22 million Rials value. Total value of other regulatory services such as (diversity in landscapes, water storage, soil formation, biologic pest control and cultural services) was negative and among these services the questioners only have willingness to pay 365 million Rials per ha in a year for cultural and water storage services. From this amount 240 million Rials was for cultural services and 133 thousand Rials was for water storage. For other services there was not any willingness to pay and they consider it as one of the municipalities' tasks.
More budgets is needed for increasing ecosystem services for saving urban ecosystem.