Ekaterina Shorohova

Carbon Balance in Forest Ecosystems of Southern Part of Moscow Region under a Rising Aridity of Climate

This study estimates carbon balance in a mixed mature forest on sod-podzolic sandy-loamy soil (Albeluvisols sandy, the Prioksko-Terrasny Nature Reserve) and in a secondary deciduous forest at the Experimental Field Station of the Institute of Physicochemical and Biological Problems of Soil Sciences, Russian Academy of Sciences (gray forest loamy soil, Luvisols loamy). CO2 emissions from soils have been continuously measured every week since 1998. Net primary production was estimated in 2000–2014 by remote sensing using the normalized difference vegetation index. Long-term weather monitoring has revealed a distinctive trend toward increasing aridity of climate in the southern part of Moscow region in the observation period (1998–2014). Based on long-term ground-based and satellite monitoring data, this study shows that in the growing season, mixed and deciduous forests of the southern part of Moscow region are the sink of carbon with a mean flux of 41–112 g C m–2, depending on the contribution of root respiration. Taking into account the CO2 emissions from soils during the cold season, the forests are very likely to function as sources of atmospheric carbon at an amount of 30–100 g C m–2 yr–1, sometimes reaching very significant values of C flux (170–300 g C m–2 yr–1). In mature forest ecosystems, a significant influence on the quantitative estimate of the C balance is hampered by the CO2 emission activity from coarse woody debris, which can reach up to 14% of the total losses of C during the decomposition of soil organic matter in the mixed forest, which turns it into a persistent source of CO2 to the atmosphere. It is shown that the sink function of the forest ecosystems was more pronounced in dry years, whereas the excessive wetness diminishes their sink potential, turning the forests into sources of carbon dioxide.

Presence of bark influences the succession of cryptogamic wood-inhabiting communities on conifer fallen logs

Predictors of cryptogamic wood-inhabiting communities need to be examined to understand the drivers of forest biodiversity. We estimated the influence of bark cover on the wood-inhabiting vegetation on conifer logs in early stages of epixylic succession in mature European boreal and hemi-boreal forests. Abundance of substrate groups with respect to log attributes was estimated with generalized linear and generalized linear mixed models. The structure and composition of epixylic communities was analysed using non-metric multidimensional scaling with subsequent environmental fitting. The abundance of true epixylics was inversely related to bark cover. In the first stage, bark cover did not influence the abundance of epiphytes and epigeous species; positively influenced the abundance of facultative epixylics on spruce logs and negatively influenced it on pine logs. In the second stage, the effect of bark cover was positive for epiphytes and epigeous species on spruce logs and for facultative epixylics independent of log species identity and negative for epigeous species on pine logs. Generalist species did not depend on bark cover. Total cover of wood-inhabiting vegetation was marginally influenced by bark cover. The effect of bark cover on epixylic vegetation at community level was negligible. In general, bark cover favours the establishment and growth of species with low substrate specificity. This preference may lead to either burial of logs by epigeous bryophytes, or facilitation of succession towards the dominance of ground vegetation.

A continuum of dead wood with various habitat elements maintains the diversity of wood-inhabiting fungi in an old-growth boreal forest

Evidence on habitat associations of threatened wood-inhabiting species in boreal forests may contribute to a better understanding of their ecology and conservation needs. We examined the diversity of wood-inhabiting fungal communities in an old-growth boreal forest with high substrate availability and continuity based on repeated surveys of fruit bodies. The number of species in morphological and functional groups in relation to coarse woody debris (CWD) attributes was estimated with generalized linear models. Additionally, we calculated species interaction networks of CWD attributes and fungal species. The composition of fungal communities was analysed using a non-metric multidimensional scaling with subsequent environmental fitting. Old conifer (especially spruce) logs and large aspen logs with branches represented the most important substrates for the red-listed species and the indicator species of old-growth boreal forests. Among “dynamic” CWD attributes such as time since tree death, decay class and stage of epixylic succession, the latter was the most important indicator of diversity of all species and their morphological and functional groups. The interaction network provided evidence of the importance of tree species diversity for fungal diversity. The composition of fungal communities was tree species specific and related to dynamic attributes, bark cover and diameter of logs. Our results suggest the importance of a continuum of dead wood from different tree species with a variety of niches such as branches, exposed wood, fragmented and complete cover of bark and patches of epixylic vegetation to maintain the assemblages of wood-inhabiting fungi in an old-growth boreal forest.

Eleven remarkable Diptera species, emerged from fallen aspens in Kivach Nature Reserve, Russian Karelia

Abstract Background In 2016, saproxylic Diptera associated with aspen (Populus tremula L.) logs were studied in the Kivach Nature Reserve, Russian Karelia, using trunk emergence traps. New information Eleven rare species of Diptera (families Limoniidae, Scatopsidae, Axymyiidae, Mycetophilidae, Sciaridae, Platypezidae, Syrphidae and Clusiidae) with poorly known distribution and ecology were recorded. For each species, basic diagnostic characteristics were provided along with the information on microhabitats. An attempt was also undertaken to outline possible associations with wood-decaying macrofungi using nonparametric correlation.