[Responses of radial growth of at different densities to drought events].

In recent years, a surge in drought occurrences has dramatically impacted tree growth worldwide. We examined the ecological resilience of plantations with varying densities (1950, 2355, and 2595 trees·hm) at the Saihanba Mechanical Forest Farm, by extracting the increment cores using the standard dendrochronological method to measure individual-tree basal area increments (BAI) as part of our assessment of ecological resilience, including resistance (), recovery (), and resilience (). The results showed that drought events occurred in 2006-2010, 2015, and 2018.

[Responses of radial growth of to abrupt warming].

To investigate the impacts of abrupt warming on tree growth, we collected tree ring cores from larch () in three different sites, including Saihanba National Nature Reserve, Pangquangou National Nature Reserve, and Fengning Qiansongba National Forest Park. Based on the tree ring method, Mann-Kendall test was used to examine the occurrence time of temperature rise mutation. We further analyzed the radial growth law of larch before and after the temperature mutation and its correlation with the monthly climate data.