Impact of China’s Permanent Basic Farmland Protection Redline and Ecological Protection Redline on Water Conservation in the Loess Gully Region

Abstract

Water conservation is crucial for sustainable ecosystem development in loess gully regions. The redlines of permanent basic farmland protection and ecological protection are key land use control zones in China, yet their impact on water conservation is understudied. The study focuses on Yan’an and constructs three scenarios: natural development (NDS), farmland protection (FPS), and ecological protection (EPS). Then, land use simulation for the three scenarios in 2025, 2030, and 2035 is carried out using the patch-generating land use simulation model. Finally, the integrated valuation of ecosystem services and trade-offs model is combined to calculate water conservation. The findings suggest the following: (1) From the temporal perspective, the water conservation of the three scenarios exhibits an incremental trend by period from 2025 to 2035, with an annual growth rate of approximately 0.65‰ for the NDS, 0.60‰ for the FPS, and 0.64‰ for the EPS. (2) From the scenario perspective, from 2025 to 2035, the annual water conservation under the FPS is 0.35‰ less than that under the NDS, while the impact of the EPS is weak at only ±0.1‰. (3) Across all scenarios, the average water conservation depth of grassland surpasses that of forestland. This study provides scientific evidence to help optimize China’s land space governance policy as well as methodological and theoretical support for related studies.