A novel methodology for assessing resources and environmental carrying capacity with emphasis on ecosystem services: A multi-disciplinary approach to sustainable urban planning

Due to increased human activities, urban areas face challenges in maintaining their environment and natural resources in support of development. As a result, it is necessary to plan according to the availability of resources and the state of the environment to achieve sustainable development. For this purpose, Carrying capacity (CC) can be used to assess the sustainability of cities as complex Social-Ecological Systems (SES). By emphasizing Ecosystem Services (ESs) and regional thresholds, this paper proposes a novel methodology to evaluate Urban Resources and Environmental Carrying Capacity (URECC). At first, an integrated simulation model is developed by combining an ecosystem services simulation model, a surface and ground water simulation model, a priority-based water allocating model, and a demands (i.e., water, food, and energy) estimation model. To evaluate URECC, various measurement indicators are developed and combined with a multi-stage decision-making (MSDM) method. Also, the decision-making sequences of management strategies and climate change scenarios are used to evaluate changes in the future. Based on the results, in the two base stages (2013-2016) and (2017-2020), without applying strategies, the average value of pressure-support, distance, and composite indices changed by +1.5%, -75.6%, and -66.7%, respectively, indicating a decrease in the CC. The future period (i.e., 2021-2040) was divided into four-year decision-making stages. According to the results, with the implementation of top sequences of strategies, the average values of pressure-support, distance, and composite indices would surpass those of maintaining the current trend by 49.4%, 123.5%, and 63.7%, respectively. In conclusion, management actions such as the development of semi-centralized and decentralized wastewater treatment networks, the simultaneous expansion of green space and built-up land, the implementation of artificial recharge, the improvement of irrigation efficiency, the management of urban water consumption, and the use of vegetation with low to medium water demands are effective for strengthening the URECC.