Microbial gradual shifts during the process of species replacement in Taihang Mountain

Abstract

IntroductionUnderstanding microbial gradual shifts along species replacement can help elucidate the mechanisms driving secondary succession, and predict microbial responses to changing environments. However, how climate-induced species replacement alters microbial processes, and whether microbial shifts follow predictable assembly trajectories remain unclear.MethodsUsing space-for-time substitution approach, we studied shifts in bacterial and fungal communities in the succession from Leptodermis oblonga to Vitex negundo var. heterophylla shrubland in Taihang Mountain.Results and DiscussionSpecies replacement, induced by climate related environmental change, significantly increased the above-ground biomass of shrublands, and TP and TK contents in topsoil. The succession from L. oblonga to V. negundo var. heterophylla communities resulted in the gradually replacement of cold-tolerant microbes with warm-affinity ones, and alterations of microbial communities involved in soil biogeochemical processes. Soil and plant variables, such as above-ground biomass, soil pH, total phosphorus, and total potassium, well explained the variations in microbial communities, indicating that the coordinated changes in plant communities and soil properties during secondary succession caused accompanied shifts in microbial diversity and composition.

Secondary succession of shrub-herb communities in the hilly area of Taihang Mountain

“…For example, Zhou and Zhang (1996) reported that widespread drought driven by high temperatures or low precipitations could lead to substantial forest decline, or replacement of drought-vulnerable with drought-tolerant species (Falk et al, 2019). As temperature rise and water availability decreases (Liu et al, 2023), the more drought-tolerant V. negundo var. heterophylla becomes the most dominant species in the hilly area of Taihang Mountain.…”

“…The climate is temperate continental monsoon, with warm summers and cool winters. Annual precipitation averages 519 mm, ranging from 200 to 1129 mm, with 74% falling between June and September (Liu et al, 2023). The monthly mean air temperature (1962-2020) was -3.07°C in January and 26.8°C in July (Liu et al, 2023).…”

“…Annual precipitation averages 519 mm, ranging from 200 to 1129 mm, with 74% falling between June and September (Liu et al, 2023). The monthly mean air temperature (1962-2020) was -3.07°C in January and 26.8°C in July (Liu et al, 2023). The study site had a total area of 9.3 km 2 and was located in an area of lowland hills with a relatively steep slope.…”

“…Starting from 1980s, a series of vegetation restoration projects, such as afforestation, banning grazing, and returning slope cropland forest or grassland, were implemented to control soil erosion, reduce ecological degradation, and promote vegetation recovery (Liu et al, 2014;Guo et al, 2021). In addition, annual mean air temperature across the study area exhibited a gradually increasing trend (Liu et al, 2023). Therefore, studies on species composition and community structure of shrublands on time-scales can help explore plant defense responses to natural stresses, predict the potential direction of vegetation succession, and inform appropriate environmental management strategies (Xie and Tang, 2017).…”