The risk of forest diseases is on the rise due to climate change and the consequential increase in extreme weather events, which disrupt the balance between pathogen, hosts, and the environment. This study analyzed two consecutive outbreaks of canker disease in Betula alnoides (Buch.-Ham. ex D. Don 1825) plantations and the temperature and precipitation changes in 2019 and 2020 in the northern Guangdong Province, China, to understand the impact of meteorological factors on disease outbreaks. We also examined the growth and mortality of B. alnoides with different gap sizes and reserved densities to explore how stand structure affects disease resistance in B. alnoides individuals. In both years, the disease outbreaks were preceded by periods of increasing heat and significant drops in humidity, as indicated by the z-score and relative similarity index. The mortality of B. alnoides due to canker disease was negatively correlated with seedling growth, which was optimized at a moderate reserved density of 225–300 trees per hectare in the upper layer and a gap size of 500–750 m². The findings suggest that closely monitoring meteorological changes and implementing afforestation with a well-managed upper layer can help mitigate the impact of canker disease in subtropical regions, particularly in the context of climate change. Further long-term studies with a more systemic approach are needed to assess the effects of thinning and gap creation in forest management.

Assessing carbon stocks in tropical forests is crucial for understanding their role in mitigating climate change. (1) Background: However, existing assessments have underestimated certain factors that can substantially influence carbon dynamics. (2) Methods: This study focuses on one such factor - buttress roots from a tropical forest. (3) Results: Our findings reveal that a significant proportion of trees (69.57%) had 3 to 5 buttress roots per tree. The total biomass of the buttress roots and the aboveground portion of the trees with buttress roots were calculated to be 8.5 tonnes/ha and 10.7 tonnes/ha respectively. The buttress root biomass accounted for 16.18% of the total tree biomass. It was observed that the presence of buttress roots during both the rainy and dry seasons increased the soil organic carbon content by an average of 20.8% in the upslope areas with buttress roots. During the rainy season, the presence of buttress roots did not affect the heavy fraction organic carbon in the soil layers in a statistically significant way. Regardless of the season, the soil respiration rate in the areas without buttress roots was higher than that in the areas with buttress roots. The presence of buttress roots had a positive effect on soil nutrient concentration in all seasons, creating a healthier environment for trees. Tree species with buttress roots had on average 20% higher organic carbon content during both the wet and dry seasons. (4) Conclusions: These findings highlight the importance of considering buttress roots in carbon stock assessments and forest management strategies. By integrating buttress roots into carbon accounting models, we can obtain more accurate estimates of carbon stock potential and develop more effective conservation and restoration strategies for tropical forests.