Natural Vegetation Area Design in an Arid Region Based on Water Resource Carrying Capacity—Taking Minqin County as an Example

Abstract

Water resource management and natural vegetation distribution status are important for the sustainable development of agricultural, ecological and socio-economic systems in arid areas, and the carrying area of vegetation is limited by the established water resources. This study proposed the concept of natural vegetation area design in arid areas based on water resource design carrying capacity and took Minqin County belonging to a typical inland arid area as an example and socio-economic water consumption, ecological water consumption and water resource utilization efficiency in the study area as the main selected factors as well as reference indicators. By calculating the water ecological footprint, water resource carrying and water resource ecological pressure index of the main natural vegetation design area in Minqin County in 2017, we analyzed and evaluated its water resource carrying status and predicted the natural vegetation areas in 2025. The results showed that there was a large gap (the increase was 13.25–9.29%) between the actual area of various types of natural vegetation in 2017 and that in 2025. The water resource utilization was more effective in various types of natural vegetation in Minqin County under the stable development model, and the water ecological deficit was approaching 0, but the utilization of forest trees other than shrubs and herbaceous plants was in an insecure state, and the water ecological deficit was less than 0. The water resource allocation schemes under the restoration model and the optimization model were safer ecological development models for natural vegetation in Minqin County, which was in a state of water-ecological surplus, and the water-ecological surplus value was greater than 0. Thus, it could be seen that coordinating the water resource supply among various types of natural vegetation in an arid area was a preferred strategy to ensure the sustainable development of regional ecology as well as an effective countermeasure to improve the water use efficiency of natural vegetation in the county to a certain extent. This study aimed to evaluate the carrying capacity of a natural vegetation area and the water pressure index under certain water supply conditions, which could provide a reasonable theoretical reference for water resource management in arid areas.