Geographic detector-based quantitative assessment enhances attribution analysis of climate and topography factors to vegetation variation for spatial heterogeneity and coupling

Abstract

As one of the most important components of terrestrial ecosystems, vegetation is essential for maintaining ecosystem functions. Excavating the independent effect and coupling of climate and topography on vegetation variation is conducive to the high-quality development of the regional ecological environment. Based on the remote sensing data of Landsat 5/7/8 and Sentinel-2, the spatiotemporal evolution of Fractional vegetation coverage (FVC) from 1990 to 2020 is explored with the Google Earth Engine (GEE). The individual effect and coupling of climate and topography factors are discussed through the geographic detector model, taking the Yellow River Basin of Henan Province (YRBHP) as the study area. The results show that: (1) The eastern and western parts of the YRBHP are densely covered with vegetation, and the central area is scarce. The FVC of the YRBHP has improved significantly from 1990 to 2020, and the proportion of improved areas is 67.7%. (2) Elevation is the strongest driving factor of FVC in the YRBHP, and the contribution rate to FVC was 0.3. (3) The coupling effect of climate and topography factors enhances the effect on FVC, among which the strongest coupling effect is elevation and precipitation. The results could dig deeper by analyzing the coupling relationship among the driving factors for providing the suitable environment condition for vegetation restoration.

Keywords

• Vegetation variation
• Fractional vegetation coverage
• Geographic detector model
• Driving factors
• Spatial heterogeneity
• Ecological restoration