Deadwood in the hemiboreal forest stands in Latvia

In Europe, the amount of deadwood (DW) varies regionally, hence national estimates of satisfactory level (EU Nature Restoration Law) are necessary. In this study, satisfactory levels of DW for Latvia were estimated based on the National Forest Inventory concerning stand age and management regime: recently managed, recently unmanaged, and stands with restricted management. In these stands, the mean values of 14.8 ± 1.8, 26.3 ± 1.6, and 38.3 ± 2.9 m3 ha−1 in which of 34.4, 42.9, and 36.6% were standing DW, were estimated, respectively. The overall mean was 23.8 ± 1.1 m3 ha−1. The estimates were higher than European mean and corresponded to the commonly applied threshold values (20–30 m3 ha−1) for the hemiboreal zone, suggesting them as satisfactory. The age-related increase in the amount of DW was faster in the recently unmanaged stands, irrespectively of restriction, where the threshold values were reached 10–20 years earlier, suggesting potential for improvements via voluntary reduction of management. The amount and type (lying or standing) of DW were age-dependent, yet the age-relations differed by tree species and management regime. Deciduous stands showed potential to accelerate DW accumulation at younger stands, hence the anticipated increase in abundance of deciduous trees would contribute to amount of DW in Latvia.