Assessing the health of climate-sensitive trees in a subalpine ecosystem through microbial community dynamics

• Published in: The Science of the total environment 2024-12, Vol.957, p.177724, Article 177724
• Main Authors: Kang, Bo Ram, Kim, Soo Bin, Hong, Jin-Kyung, Ahn, Seok Hyun, Kim, Jinwon, Lee, Nayeon, Lee, Tae Kwon
• Format: Article
• Language: English
• Subjects: Abies; Climate Change; Ecosystem; Korean fir; Microbial network; Microbiota; Neutral community model; Republic of Korea; Soil - chemistry; Soil Microbiology; Trees
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.177724

Climate change has significantly affected the subalpine ecosystems, leading to mass die-offs of the Korean fir tree, a key climate-sensitive species in these environments. Proactive analysis of the phenotypic responses of these trees to climate change or the establishment of preemptive strategies for trees to adapt to these environmental changes remains a challenge. The current study aimed to investigate the impact of climate change on the health of Korean fir (Abies koreana) in the subalpine ecosystem of Jirisan Mountain, South Korea. We integrated soil physicochemical analyses, microbial community dynamics, neutral community model, and network analyses to examine the relationships between tree health and microbial communities. Our findings revealed significant changes in soil chemical properties, including pH and nutrient concentrations, across the various health statuses of trees. Microbial community analysis demonstrated shifts in bacterial and fungal communities corresponding to the health continuum of the trees, with decreased diversity and altered composition in the declining trees. A remarkable increase in modularity of the microbial network and a clear transition from stochastic to deterministic microbial community assembly processes were observed as the trees progressed from a healthy to a dead stage. Two bacterial genera, Bradyrhizobium and Burkholderia, along with an unclassified fungal group from Basidiomycota, were identified as key microbial indicators of good tree health. This study highlighted the importance of microbial communities as bioindicators for assessing the health of subalpine ecosystem and its resilience to climate change, offering valuable insights into the conservation and management strategies for subalpine ecosystems. [Display omitted] •Climate change accelerated Korean fir die-off events in subalpine ecosystem.•Soil chemistry and microbial community changes linked to tree health decline.•Increased modularity in microbial networks observed under fir stress.•Microbial shift from stochastic to deterministic processes with declining tree health.•Bradyrhizobium and Burkholderia are pinpointed as vital indicators of tree health.