نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه محیط زیست، دانشکده شیلات و محیط زیست، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
2 گروه مهندسی آب، دانشکده مهندسی آب، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Introduction:
Ecosystems provide a wide range of services that vary in quantity and quality depending on the type of ecosystems and their status. Estimating the ecosystem services value (ESV) is very important to support land use planning processes. Ecosystem services are under great pressure due to urban growth and its effects. The human activities that reduce ecosystem services include land use/land cover (LU/LC) change driven by agricultural activities and urban growth. In this paper, we assessed LU/LC dynamics in Golestan Province using change detection and Markov chain as inputs for ESV of different land use types to estimate the amount of services. We also used sensitivity analysis to explore the robustness of results by 50% adjustment of value coefficients.
Material and methods:
Golestan Province is one of the 31 provinces of Iran, located in the south of the Caspian Sea. In this study, multi-temporal data of LU/LC were produced from multispectral Landsat imagery acquired on two separate years (1984 and 2015). We also analyzed ecosystem service values for 2035. Markov chain was used for quantity forecasting. Markov Chain Analysis is a convenient tool for modeling land use change, when changes and processes in the landscape are difficult to describe. LU/LC data were analyzed using Ecosystem Services Value (ESV) for different biomes.
Results and discussion:
Land cover classification indicated that settlements were the most increased land cover over the study period. From 1984 to 2014, ecosystem service values of forests decreased from 1722 to 952 million dollars. Annual value of 22 ecosystem services was estimated. In terms of the estimated ESV, food production, raw materials, climate regulation, nutrient cycling, biological control, genetic diversity and recreation were reduced while the rest of ESVs were increased/decreased. The effect of using different coefficients to evaluate the total ESV in Golestan Province was evaluated. The coefficient of sensitivity (CS) of these analyses was less than one in all cases. Our results of analyses indicated that the total ecosystem values estimated for Golestan Province were relatively inelastic, which also suggests that our ecosystem value evaluation is reasonable. According to the LU/LC within the landscape, our results indicate that rangelands and forests provide a higher level of ecosystem service than others due to the relatively larger area coverage and higher value coefficients and hence a reduction in this particular component of the ecosystem hampers a balanced flow of services from the landscape.
Conclusion:
Ecosystem service value estimation based on LU/LC analysis is very important to indicate the changes in the amount of services through urban growth on spatial and temporal scales. Such estimations in local, regional and global scales are important in influencing land use planning processes through modifying national accounting systems to reflect the true values of ecosystem services so that it will be ultimately used as a basis for sustainable development. Another benefit could be related to land use optimization projects to increase ecosystem services.
کلیدواژهها [English]