Ecological Indicators (Sep 2024)
Spatial pattern and formation mechanism of predominant species using an unmanned aerial vehicle in the Gobi area, southern slopes of the Tianshan Mountain Range
Abstract
Understanding the spatial pattern of vegetation in the Gobi area is of paramount importance for preserving its vegetation and the overall stability of the ecosystem. Here, we investigated the populations of the predominant species, Ephedra przewalskii, at various locations within the alluvial fan situated in the southern foothills of the Tianshan Mountains in the Gobi area. The location of the E. przewalskii distribution in the sample plot was extracted from unmanned aerial vehicle (UAV) images. This article analyzes the distribution patterns of the predominant species based on different null models, tests whether the distribution patterns are affected by habitat heterogeneity, and examines whether other ecological processes affect these patterns. Additionally, using the variance decomposition method, we analyze the explanatory power of habitat factors on the distribution patterns of the predominant species. The results show that: (1) Using UAVs to locate the distribution of vegetation information for sparse vegetation pattern analysis in the Gobi region has good applicability and prospects; (2) the frequency, density, and coverage of E. przewalskii decrease sharply with decreasing altitude. At a small scale (0∼10 m), the E. przewalskii population is mainly aggregated, whereas on a large scale (>10 m), it primarily exhibits uniform or random distributions; (3) the E. przewalskii population distribution pattern is significantly affected by habitat heterogeneity, mainly on a large scale. The species distribution in the study area strongly correlates with the altitude, soil moisture, and topographic wetness index. Habitat factors can explain 64.2 % of the reasons for species distribution; and (4) The clustering of E. przewalskii population at the apex of the alluvial fan is primarily driven by facilitation, whereas at the middle and bottom sections, it is predominantly influenced by habitat heterogeneity and restricted diffusion. The results enhance our comprehension of the spatial patterns and environmental adaptation mechanisms exhibited by the predominant species in the study area. Furthermore, they provide a scientific foundation for ecological conservation and biodiversity protection in the environmentally vulnerable Gobi region.
