Exploring the spatio-temporal dynamics of life support system capacity of urban regions based on ecosystem health assessment (the case of Tehran, Iran)

In this study, the capacity of the life support system in Tehran was evaluated based on the ecosystem health assessment (VOR model) from 1988 to 2021. The capacity of the life support system in cities is severely declining due to their physical growth and increased construction. This study showed that from 1988 to 2021, built-up areas in Tehran increased by 67.45%, while green and open areas decreased by 63.84% and 79.21%, respectively. Also, according to the results of this research, in most regions of Tehran, vigor, organization, elasticity, and ecosystem health have declined sharply during the period under review. Examining changes in ecosystem health classes shows that the very weak class increased from 1988 (9.38%) to 2021 (27.93%). The weak class increased from 1988 to 2021, from 29.38% to 51.14%, respectively. In contrast, the percentage of good and very good classes decreased to 0 in this period. The results showed that the mean EH in 1988 was 0.41, while in 2021, it was 0.22, and the coefficient of variation (CV) increased to 64.01 in 2021. Estimates and mapping in this study show that the Organization Index significantly affected the ecosystem health of Tehran, which shows the importance of the composition and configuration of the life support system in determining the urban ecosystem's health. In conclusion, the quantitative assessment of EH on the urban area scale provides a better understanding of the construction process and its ecological effects on urban environmental quality.