Response of Eco-environmental Quality to Climate Change and Land Use in Loess Plateau from 2000 to 2020

Abstract

[Objective] The spatial and temporal changes of ecological environmental quality (EEQ) in response to climate and land use changes on the Loess Plateau were analyzed in order to provide a basis for the formulation of reasonable ecological protection measures and land development on the Loess Plateau that will promote high-quality development. [Methods] Based on an improved remote sensing ecological environmental index and climate and land use data, we determined the spatial and temporal characteristics of EEQ on the Loess Plateau from 2001 to 2020 using Theil-Sen trend analysis at the image pixel scale. [Results] ① During the study period, EEQ values on the Loess Plateau showed small fluctuations of rising, falling, and rising, and the fluctuations slowed down from 2010 to 2020 compared with the time period of 2001 to 2010. EEQ values generally showed a spatial pattern of “higher in the southeast and lower in the northwest”. Compared with the period from 2001 to 2010, the period of 2010 to 2020 exhibited an area of significant increase in EEQ that shifted from the southeast to the north-central region, and an area of significant decrease in EEQ that shifted from the northwest to the east. ② Precipitation had an overall positive effect on EEQ, with a significant positive correlation from 2001 to 2007. Due to the interference of other factors in the later period, the driving force increased, and the influence was small in areas with less vegetation coverage. Temperature had a negative effect on EEQ in most areas, with less effect compared with precipitation, and greater effect in dense urban areas. ③ During the study period, large transfers of cropland to grassland, grassland to woodland, and unused land to grassland were the main driving forces for the steady to good pattern of EEQ in the study area, while the transfer of cropland to construction land and of grassland to unused land were important factors causing the decline of EEQ. [Conclusion] EEQ on the Loess Plateau was influenced by both climate and land use. The influence of precipitation on EEQ was greater than that of temperature, and land use shifts generally showed positive effects on EEQ but with spatial heterogeneity. Greater attention should be given to regional ecological conservation in urban clusters within the region in the future.

Keywords

• ecological environmental quality
• loess plateau
• climate change
• land use