The influence of ecological engineering projects on dust events: A case study in the northern China

Abstract

Since the late 1970s, many large-scale ecological engineering projects have been implemented to mitigate and remediate hastily degraded ecological condition in northern China. The purpose of this study is to assess the influences of these projects by examining the correlation between natural factors and dust events. First, the spatiotemporal variations in dust events in study area are analyzed, using the dust report data of 270 stations of the synoptic observation from 1978 to 2018. Furthermore, the variations in vegetation and meteorological conditions are evaluated and the correlation between dust events and various natural factors is investigated. The results show that dust events are generally decreased, along with significant improvement in vegetation, especially on the edge of desert areas. Moreover, >75% of dust events occurred before year 2000. Also, spatial distribution of dust events is quite diverse. The area with declining dust events is accordance with the area with increasing NDVI, while the NDVI improving trend in 2000–2018 is more significant than that in 1982–1999. Through hotspot analysis, evaporation and relative humidity are two leading factors with higher relative importance and correlation coefficient in all groups. Nonetheless, owing to substantial geographical difference and climatic dissimilarity, there are noticeable differences among various groups, as RHU is the only factor with highest correlation in all six groups, EVP is the highest correlated factor in G1 and G3, and WIN dominates in G2, G4, G5, and G6. These findings can be important guidelines for dust storm prevention design in ecological engineering projects