Tree canopy accession strategy changes along the latitudinal gradient of temperate Northeast Asia

Abstract

Aim Understanding how natural forest disturbances control tree regeneration is key to predicting the consequences of globally accelerating forest diebacks on carbon stocks and forest biodiversity. Tropical cyclones (TCs) are important drivers of forest dynamics in Eastern Asia, and it is predicted that their importance will increase. However, little is known about the impact of TCs on forest regeneration. Location Latitudinal gradient from south Korea (33° N) to the Russian Far East (45° N). Time period Last 300 years. Major taxa studied Quercus mongolica, Abies nephrolepis and Pinus koraiensis. Methods We explored the effects of TC activity on canopy accession strategies derived from long‐term tree radial growth patterns along a 1,500‐km latitudinal gradient of decreasing TC activity. We analysed canopy accession strategies for > 800 trees of three widely distributed tree species by dividing them into gap trees (GTs), which established immediately after gap formation, and released trees (RTs), which accessed the upper canopy after a period of competitive suppression. Results We found a substantial decrease in GTs and increase in RTs proportionally along the gradient of decreasing TC activity. Pinus koraiensis and A. nephrolepis exhibited high variability in the proportions of the individual canopy accession strategies along the latitudinal gradient, whereas it was more stable for Q. mongolica. We identified the gradient of TC activity as the main driver influencing canopy dynamics and thus changes in life‐history traits for P. koraiensis and Q. mongolica, whereas maximal growth rate was the main driver for A. nephrolepis. Main conclusions Flexibility in growth strategies enabled the studied species to cover extensive areas and indicates that they will be able to cope with shifts in disturbance regimes induced by the poleward migration of TCs and increasing TC intensity. Our results highlight the canopy accession strategy as an ecological indicator of past disturbance activity.

Assessment of the mixed coniferousbroadleaved forest canopy disturbance induced by typhoon Maysak (2020) using drone-borne images near Vladivostok, Russia

“…According to the study of the felling area, the juvenile spe cimens of A. holophylla tolerate a sudden change in lighting quite well, while juvenile specimens of P. koraiensis, suddenly exposed to light from under the canopy, wilt and slow down in growth (Vasil'ev & Kolesnikov 1962). A study of the typhoon activity influence on the canopy accession strategies of Abies nephrolepis, Pinus koraiensis, and Quercus mongolica, based on long-term patterns of radial tree growth along a 1500 km latitudinal gradient of typhoon activity decline, showed that the typhoon activity gradient is an important indicator influencing changes in the life cycle traits of P. koraiensis and Q. mongolica, and not so im por tant for the growth strategy of A. nephrolepis (Janda et al 2021). Flexibility in growth strategies indicates that P. koraiensis and Q. mongolica, will be able to cope with shifts in disturbance patterns caused by poleward migration of typhoons and increased typhoon intensity.…”

“…Depending on the kind of transformation, typhoons can cause heavy rains, strong winds, and catastrophic floods. With global climate change, typhoons began to move to northern latitudes, and their frequen cy and severity increased significantly over the past 50 years (Altman et al 2018, Janda et al 2021. Nowadays, typhoons cause disturbances in temperate and boreal forests, which were rarely affected by tropical cyclones in the past (Korznikov et al 2022).…”

Tropical Cyclone Disturbances Induce Contrasting Impacts on Forest Structure, Plant Composition, and Soil Properties in Temperate Broadleaf and Coniferous Forests

“…In addition, documented intensification of tropical cyclones and poleward migration poses a significant threat to these unique ecosystems [3,46,47]. Hence, it is necessary to understand the complex responses of forests to tropical cyclone disturbances to mitigate the possible impacts of recent and projected shifts in tropical cyclone activity on forest ecosystems [48]. South Korea experiences strong landfall tropical cyclones, and there has been a recorded increase in the threat of tropical cyclone activity over the last decades [49,50].…”