We assessed total mercury (THg) concentrations and greenhouse gas (GHG) emissions in pristine and managed hemiboreal peatlands in Latvia, aiming to identify environmental factors that potentially affect their variation. The THg concentrations in soil ranged from <1 µg kg⁻¹ to 194.4 µg kg⁻¹. No significant differences between THg concentrations in disturbed and undisturbed peatlands were found, however, the upper soil layer in the disturbed sites had significantly higher THg concentration. During May–August, the mean CO₂ emissions (autotrophic and heterotrophic respiration) from the soil ranged from 20.1 ± 5.0 to 104.6 ± 22.7 mg CO₂-C m⁻² h⁻¹, N₂O emissions ranged from −0.97 to 13.4 ± 11.6 µg N₂O-N m⁻² h⁻¹, but the highest spatial variation was found for mean CH₄ emissions—ranging from 30.8 ± 0.7 to 3448.9 ± 1087.8 µg CH₄-C m⁻² h⁻¹. No significant differences in CO₂ and N₂O emissions between disturbed and undisturbed peatlands were observed, but CH₄ emissions from undisturbed peatlands were significantly higher. Complex impacts of environmental factors on the variation of THg concentrations and GHG emissions were identified, important for peatland management to minimize the adverse effects of changes in the biogeochemical cycle of the biophilic elements of soil organic matter and contaminants, such as Hg.

This study examines microhabitat abundance and composition on retention trees in 20 young stands in Latvia that were clear-cut between 2002 and 2004. Retention trees play a vital role in sustaining biological diversity after clear-cutting, but their mortality rate is often high due to post-harvest environmental changes. This study compares tree-related microhabitat (TreM) abundance and composition on retention trees of different dimensions, species, and vitality. The tree height and diameter were measured, and the living status and position of each tree were determined. The research questions of the study were to assess the relationships between TreMs, tree dimensions, and species, as well as to compare the occurrence of TreMs on living and dead wood. The comprehensive analysis revealed that larger tree diameters and specific tree species (Populus tremula, Fraxinus excelsior, and Salix caprea) lead to a higher abundance of TreMs. The results also highlighted the importance of preserving deadwood within forest stands as it enhances the observed abundance of TreMs. This study provides the missing information on TreMs in Latvia, thus providing data for comparison in a wider region.

Retention of trees from the previous generation is one of the most widespread conservation practices in forests used for timber production. Despite the comparatively long history of this approach in Europe, there is a lack of long-term studies on the effectiveness of retention trees in preserving epiphyte communities. We compared the diversity of bryophyte and lichen species on retention trees in 20 young forest stands in Latvia in two assessments, 11 years and 18 years after clearfelling. Linear mixed-effects models showed that richness of both lichens and bryophytes remained stable during the assessment years, while bryophyte cover and diversity on retention trees increased over time. The main indicator of higher species richness, cover and diversity on retention trees in managed forests in hemi-boreal vegetation zone was the tree species, with deciduous trees playing the key role. They also provided essential habitat for rare species. Regarding bryophytes, ash, elm, and aspen can be suggested as more efficient retention trees, thus aiding the continuity of bryophyte succession in young forest stands. For lichens, lime could also be prioritised.

Retention forestry is a commonly used approach to include biodiversity conservation in forest management of production forests. Tree-related microhabitat (TreM) assessment is suggested as a good practice for the selection of habitat trees to retain. TreMs are small structures on living or dead trees that provide living substrates, shelter, breeding places, or food sources for various groups of organisms, therefore, they can be a good indicator of the presence of forest-dwelling species. However, the knowledge linking bryophyte and lichen species diversity with TreMs is still scarce. In this study, TreMs and bryophyte and lichen species composition were assessed on living retention trees in 39 young forest stands (10–20 years post-cut) in Latvia to test whether the richness of epiphytes on retention trees up to 2 m height is related to the number of TreM types. There was a strong positive correlation between the total number of TreMs and lichen richness on Betula pendula (R_s = 0.66; p < 0.001), a moderate positive correlation on Alnus glutinosa (R_s = 0.56; p = 0.040), but no such link was found for other evaluated species. Trees with TreMs—foliose and fruticose lichens and dead branches–hosted more lichen species than trees without these TreMs. The number of bryophyte species on a tree was explained mainly by tree species, and bryophyte richness did not significantly correlate with the total number of TreMs. These findings suggest that retention trees of diverse species and with a high number of TreMs can contribute to maintaining greater species richness of epiphytic bryophytes and lichens.

The ecosystem services framework is a convenient approach for identifying and mapping nature’s contributions to people, and an accurate assessment of ecosystem services potential is the first step in the decision support process of well-informed land management planning. The approach we use for forest ecosystem services potential assessment in Latvia is based on the principles of the matrix model and biophysical data of the forest inventory database, and it is comparable to other assessments previously carried out in the Baltic Sea Region. The proposed approach supports spatial planning and may be integrated with assessments of other ecosystems based on the same methodological principles. The evaluation results reflect the high spatial heterogeneity of forest types in Latvia. Future work should include integrating ecosystem services flows and demand into the assessment, developing additional indicators for culturally important ecosystem services, and introducing socio-cultural valuation to account for a broader set of stakeholders and values.

Forest road verges are common secondary habitats in managed forest landscapes, yet their vegetation development remains insufficiently documented. We investigated successional changes in ground vegetation on newly built forest road verges over an eight-year period using six repeated surveys, analysing taxonomic diversity, ecological indicator values and their Rao’s quadratic entropy, as well as functional trait composition based on Grime’s CSR strategies and Raunkiær’s life-forms. Our results showed a continuous increase in taxonomic richness throughout the study period, while niche differentiation increased mainly after the first year following road construction and remained relatively stable thereafter. Among the ecological preference indicators examined, nutrient availability consistently showed the highest niche differentiation, whereas light and moisture showed comparatively lower variation. Functional composition shifted from ruderal-dominated communities toward an increasing representation of stress-tolerant and competitive species. The obtained results of mixed-effects models revealed high spatial variation among road sections, indicating that early secondary succession on forest road verges is shaped by both successional processes and local environmental conditions.