In the Baltic States region, anthropogenic disturbances at different temporal and spatial scales mostly determine dynamics and development phases of forest ecosystems. We reviewed the state and condition of hemiboreal forests of the Baltic States region and analyzed species composition of recently established and permanent forest (PF). Agricultural deforestation and spontaneous or artificial conversion back to forest is a scenario leading to ecosystems designated as recent forest (RF, age up to two hundred years). Permanent forest (PF) was defined as areas with no records of agricultural activity during the last 200 yr, including mostly forests managed by traditional even‐aged (clear‐cut) silviculture and salvage after natural disturbances. We hypothesized that RF would have distinctive composition, with higher dominance by hardwoods (e.g., aspen and birch), compared to PF. Ordination revealed divergence in the RF stands; about half had the hypothesized composition distinct from PF, with a tight cluster of stands in the part of the ordination space with high hardwood dominance, while the remaining RF stands were scattered throughout the ordination space occupied by PF with highly variable species composition. Planting of conifers, variability in site quality, and variability in spatial proximity to PF with relatively natural ecosystem legacies likely explained the variable compositions of this latter group of RF. We positioned the observations of RF in a classic quantification of site type conditions (based on Estonian forest vegetation survey previously carried out by Lõhmus), which indicated that RF was more likely to occur on areas of higher soil fertility (in ordination space). Climatic and anthropogenic changes to RF create complex dynamic trends that are difficult to project into the future. Further research in tracing land use changes (using pollen analysis and documented evidence) should be utilized to refine the conceptual framework of ecosystem legacy and memory. Occurrence and frequency of deforestation and its characteristics as a novel disturbance regime are of particular interest.

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A large area of Estonian hemiboreal forest is recovering from clear-cut harvesting and changing carbon (C) balance of the stands. However, there is a lack of information about C- source/sink relationships during recovery of such stands. The eddy covariance technique was used to estimate C-status through net ecosystem exchange (NEE) of CO2 in two stands of different development stages located in southeast Estonia in 2014. Measured summertime (June–September) mean CO2 concentration was 337.75 ppm with mean NEE −1.72 µmol m−2 s−1. June NEE was −4.60 µmol m−2 s−1; July, August, and September NEE was −1.17, −0.77, and −0.25 µmol m−2 s−1, respectively. The two stands had similar patterns of CO2 exchange; measurement period temperature drove NEE. Our results show that after clear-cutting a 6-year-old forest ecosystem was a light C-sink and 8-year-old young stand demonstrated a stronger C-sink status during the measurement period.

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