Spatiotemporal modeling of urban land cover changes and carbon storage ecosystem services: case study in Qaem Shahr County, Iran

Considering the level of carbon stored in green lands, vast forest ecosystems with large volumes of biomass can play an important role in carbon sequestration and reduction of man-made CO2 emissions. Accordingly, the present study aims to determine the amount of carbon stored in Qaem Shahr County, north of Iran, as part of the remaining Hyrcanian forests. To achieve the research objective, land cover (LC) classification is performed by object-oriented classification. Also, LC changes are modeled for 2027 using CA-Markov model. Then, the carbon storage sub-model of Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model is used to estimate carbon storage level and distribution in the area under study. The results show that the highest amount of stored carbon is in forest areas, which is estimated to be 18.228 megagram (Mg) in 2014. Also, results show that in case of continuation of the current trends, the amount of stored carbon will be reduced by 321,216.68 Mg by 2027. The main reason of this reduction is attributed to the decrease in plant biomass and soil affected by this ecosystem, which has been caused by increased built area in the region, destruction of forest, and range of LCs in recent years. Finally, the results show that urban development and the built lands, in general, have a considerable effect on reducing carbon storage in a nearby town with broad-leaved forests as expected. Therefore, proper planning and management of the development process is necessary in the region.