The liverwort flora of Karelian part of the Vodlozersky National Park (Russia)

An updated list of liverworts in the Karelian part of Vodlozersky National Park is presented, containing 52 species. Twenty-three species were recorded in the National Park for the first time. Heterogemma capitata was found in Karelia for the first time; Calypogeia fissa and Tritomaria exsecta were reported for the second time in the region. The observations of the three species form the northern limit of their global range. New localities are reported for five Karelian red-listed species (Calypogeia suecica, Geocalyx graveolens, Pellia endiviifolia, Scapania apiculata, Syzygiella autumnalis)

Research on retention forestry in Northern Europe

Retention approaches in forest management are today common in several North European countries, integrated into the clearcutting practice as a way to promote biodiversity and maintain ecosystem functions. Individual green trees and retention patches (tree groups) are retained at final harvest, and deadwood is left at site or created. Here, we review research on retention in Sweden, Finland, Norway, the Baltic States, and NW Russia, with special focus on biodiversity. Following the first publication in 1994, about 180 peer-reviewed articles have been published. We present results from a systematic search of the retention literature, separated into the following topics: buffer zones, retention patches, high stumps, other types of deadwood, European aspen Populus tremula, and cost-efficiency. Russian literature is synthesized separately since studies from this region have so far almost exclusively been published in the Russian language. Furthermore, we describe six ongoing large-scale, replicated experiments with varying retention levels, five in Finland and one in Sweden, and summarize their main results. Among main conclusions for practice from the literature and experiments are that retention patches as large as 0.5 ha and 10-m-wide buffers to watercourses are not enough to maintain pre-harvest species composition but survival of forest species is still larger than on conventional clearcuts. Deadwood on clearcuts may present important habitats to saproxylic species, including rare and red-listed ones and a prioritization of tree species per stand is recommended. We identify several important future research directions including switch of focus towards the landscape as well as the species population level. Surveys in parts of European Russia where retention has been unintentionally implemented already for a century would indicate possible future trajectories of biodiversity and their drivers in other regions of Northern Europe. A stronger link to ecological theory would help in study designs and in the formulation of predicted outcomes.202

Säästöpuumetsätaloudella monimuotoisuutta talousmetsiin

Non peer reviewe

Globally consistent climate sensitivity of natural disturbances across boreal and temperate forest ecosystems

Disturbance regimes are changing in forests across the world in response to global climate change. Despite the profound impacts of disturbances on ecosystem services and biodiversity, assessments of disturbances at the global scale remain scarce. Here, we analyzed natural disturbances in boreal and temperate forest ecosystems for the period 2001-2014, aiming to 1) quantify their within- and between-biome variation and 2) compare the climate sensitivity of disturbances across biomes. We studied 103 unmanaged forest landscapes with a total land area of 28.2 x 10(6) ha, distributed across five continents. A consistent and comprehensive quantification of disturbances was derived by combining satellite-based disturbance maps with local expert knowledge of disturbance agents. We used Gaussian finite mixture models to identify clusters of landscapes with similar disturbance activity as indicated by the percent forest area disturbed as well as the size, edge density and perimeter-area-ratio of disturbed patches. The climate sensitivity of disturbances was analyzed using Bayesian generalized linear mixed effect models and a globally consistent climate dataset. Within-biome variation in natural disturbances was high in both boreal and temperate biomes, and disturbance patterns did not vary systematically with latitude or biome. The emergent clusters of disturbance activity in the boreal zone were similar to those in the temperate zone, but boreal landscapes were more likely to experience high disturbance activity than their temperate counterparts. Across both biomes high disturbance activity was particularly associated with wildfire, and was consistently linked to years with warmer and drier than average conditions. Natural disturbances are a key driver of variability in boreal and temperate forest ecosystems, with high similarity in the disturbance patterns between both biomes. The universally high climate sensitivity of disturbances across boreal and temperate ecosystems indicates that future climate change could substantially increase disturbance activity.Peer reviewe

Mineralization and fragmentation rates of bark attached to logs in a northern boreal

a b s t r a c t Predicting the characteristics of coarse woody debris (CWD) and its importance for biodiversity, carbon and nutrient cycling requires narrowing the uncertainties in bark decomposition rate assessments. We estimated bark decomposition rates and compared them to wood decomposition rates of birches (Betula pubescens and Betula pendula), Siberian fir (Abies sibirica), Siberian pine (Pinus sibirica) and Siberian spruce (Picea obovata) in the northern boreal forest of the Komi Republic, Russia. Estimates were made based on the mass loss of bark attached to above-ground fallen and leaning logs dated to have fallen from 1 to 168 years previous to sampling. A single-exponential model was used to estimate the mass loss of bark attached to the logs. Decomposition rate estimates of all log bark included mass loss due to fragmentation. Mineralization rate as mass loss per surface area was estimated for non-fragmented bark pieces. The initial bark mass of the tree base was higher compared to that of the rest of the log; it did not depend neither on the tree species nor on the log size. The proportional rate of bark mineralization was the same for Siberian fir, Siberian pine and Siberian spruce logs -0.040 yr À1 . The mineralization rate of birch bark was 0.009 yr À1 . Bark fragmentation accelerated mass loss. Variation in bark decomposition rates was explained by tree species and log diameter and did not depend on tree mortality mode. The bark turnover time (t 95 ) was 302, 224, 149, 140 and 117 years for birch, fir, spruce, Siberian pine with diameter more than 41 cm, and Siberian pine with diameter less than 40 cm, respectively. Bark decomposed faster than wood for fir (0.034 vs. 0.026 yr ). The different decomposition rates of wood and bark suggest that considering wood and bark together as one substrate can result in a less accurate portrayal of decomposition patterns. These bark decomposition rates can be used for modelling carbon dynamics in similar ecosystems. Knowing the turnover time of log bark for these tree species also facilitates the prediction of the quality of CWD in biodiversity studies in boreal forests

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

201