Coupled PLUS-InVEST Modeling of Land Use Change and the Economic Valuation of Carbon Storage in Xi'an, China

This study develops and applies a coupled PLUS-InVEST modeling framework to examine the spatial dynamics of land use patterns and carbon storage in Xi’an (2000–2020). Four development scenarios—Business as Usual (BAU), Environmental Protection Scenario (EPS), Economic Profit (EP), and Cultivated Land Protection Scenario (CPS)—are constructed to assess and predict the spatiotemporal variations in land use carbon storage by 2030. Drawing on the theory of the time value of money, compounded present and future value formulas are employed to estimate the economic benefits derived from regional carbon storage over the period 2000–2030. Our results reveal pronounced structural shifts in land use, characterized by a sustained decline in cultivated land and accelerated expansion of construction land, contributing to a cumulative reduction of 2.0812 million tons of carbon storage over the two decades. Scenario-based projections demonstrate substantial variation in carbon storage by 2030: the EPS and CPS scenarios are expected to yield net increases of 541.4 and 63.5 thousand tons, respectively, while the BAU and EP scenarios result in declines, with the EP scenario exhibiting the greatest loss (352.7 thousand tons) due to intensified urban development. Between 2000 and 2020, the economic value of carbon storage in Xi’an expanded by 8.125 billion yuan, reflecting the significant appreciation of carbon prices over the two decades. Compared to the 2020 baseline, the value of carbon storage under the EPS would reach 26.389 billion yuan by 2030, significantly surpassing other scenarios. These findings highlight the ecological and economic benefits of the EPS pathway, offering a compelling reference for optimizing land resource allocation and promoting sustainable regional development.