Study on delineation of core vegetation protection areas in the lower reaches of Tarim River based on SCP model

Abstract

The lower reaches of the Tarim River serve as a crucial ecological barrier preventing the merger of the Taklimakan and Kumtag deserts. They have long faced water scarcity and intensifying conflicts between water use for oasis agriculture and desert ecosystems. Therefore, identifying the core vegetation conservation area and enhancing the effectiveness of ecological protection in this area are of paramount importance. Current research on the lower Tarim River mainly focuses on assessing ecological water conveyance benefits, monitoring vegetation restoration, and estimating ecological water requirements, while studies on delineating the core vegetation conservation area are notably lacking. However, arid regions often suffer from a scarcity of climate, environment, conservation costs, and biodiversity data, which makes existing delineation methods difficult to apply directly to the lower Tarim River. Consequently, based on local ecological features, this study proposes a method for delineating the core vegetation conservation area using a Spatial Conservation Planning (SCP) model that incorporates vegetation type, fractional vegetation cover (FVC), and groundwater level. The research generated a conservation priority sequence for the lower reaches. The core vegetation conservation area was defined as regions with FVC ≥ 0.3, groundwater level ≥ −6 m, and a priority ranking within the top 20% of the priority sequence. The final delineation identified a total core conservation area of 81 km², mainly distributed across 11 vegetation patches each > 1 km². The delineation of the core conservation area provides precise spatial targets for ecological water conveyance and improves vegetation protection efficiency in the lower Tarim River. By embedding groundwater-vegetation coupling into an SCP framework and generating dynamically adjustable priority rankings, this study provides a replicable methodological template for precision conservation in other data-limited arid inland river basins-moving beyond species-centric or static zoning approaches toward adaptive, community-level ecosystem management.