Fuscopannaria leucosticta is a rare lichen that exhibits an apparent specificity for old wet forests in eastern Canada, and may, consequently, be sensitive to anthropogenic disturbance. Estimates of the current distribution and population size are highly uncertain. Effective conservation planning requires improving our understanding of both its current distribution and the factors that influence habitat suitability. We built a MaxEnt distribution model with interpolated climate data, depth to water table mapping, forest inventory data, and herbarium collection data for F. leucosticta in New Brunswick, Canada. We tested model performance via field verifications in high-probability areas with no record of previous surveys. We found F. leucosticta in 13 out of 22 previously unsurveyed locations with a predicted high probability of occurrence. Selected variables included the presence of cedar in the canopy and a lack of recent anthropogenic disturbance, as well as mean annual rainfall and degree days above 0°C. These associations are likely a result of the lichen's low reproductive output and the thermal and hydration requirements of its cyanobacterial photobiont. Our study affirms several previous claims about habitat associations of the species, and provides focus for conservation efforts in the future.

The Burgundy truffle (Tuber aestivum Vittad.) has a wide-ranging distribution across Europe, yet its ecology is far from being well understood. For instance, although the literature on the ecophysiology of this species is dominated by the symbiosis with deciduous hosts, the real range of hosts in nature seems to be much wider than the current distribution of T. aestivum. The aim of this study was to determine the relative importance of abiotic (soil) and biotic (vegetation) properties in determining the performance of T. aestivum in this pioneering stage of research on truffles in Poland. Soil parameters influenced the formation of T. aestivum fruiting bodies more strongly than plant composition. The number of fruiting bodies increased with increasing concentration of soil calcium and phosphorus. The number of plant species was the only significant predictor among the investigated vegetation characteristics. The influence of this predictor was positive, as an increasing number of fruiting bodies was found when the number of plant species was higher. The presence of truffle fruiting bodies was significantly correlated with the presence of five plant species, viz.: Brachypodium sylvaticum, Cephalanthera damasonium, Cornus sanguinea, Sanicula europaea and Viola mirabilis.

In the boreal forest of eastern North America, the distribution of eastern white cedar (Thuja occidentalis) is characterized by a latitudinal fragmentation gradient from south to north. Marginal populations could be outposts allowing cedar to expand its presence in the north in response to climate change. This study aimed to characterize the spatio-temporal regeneration dynamics of 20 marginal cedar stands in order to evaluate their expansion capacity into adjacent black spruce stands. Cedar recruitment within marginal cedar stands was mainly by layering, which allowed the species to maintain for a long time in the landscape. However, the rate of expansion of marginal stands into adjacent black spruce stands through seed dispersal was very low (0.28 m.year^–1) and it was negatively influenced by distance to seed trees. Substrate had no significant effect. Global warming could lead to increased seed production by cedar, which could favour the species' expansion at its northern distribution limit. However, global warming could also increase the frequency and severity of wildfires, which would have a negative effect on cedar expansion capacity.

Climate-vegetation models predict rapid northward advance of the subarctic forest-tundra in the coming century, although modelled responses may not be congruent with field data. This study aimed to determine how forest-tundra vegetation has responded to climate change in north-central Canada. Vegetation cover and gradients were mapped and compared to changes in climate parameters between 1955 and 2006. Increased aridity and annual and July warming corresponded to spatial isotherm shifts of one-half the width of the forest-tundra transition. Over the 51-year period, the areal extent of live trees decreased 26% (5227 km²) while the areal extent of recently-burned trees increased 16-fold (7768 km²). Changes in the areal extent of treeless wetland, tall shrubs, and upland tundra were non-significant. There was significant forest loss in the southern forest-tundra and modest forest gain in the northern forest-tundra. Overall, forest loss outpaced forest gain. The forest-tundra increased in areal extent by ∼6% via an overall broadening of the transition region. Contrary to model predictions, no appreciable northward migration of the forest-tundra was detected over the 51-year period despite significant climate change. Increased wildfire activity and moisture stress may limit the potential of tree vegetation to expand northward under a warming climate.

Root development is important to ensure tree survival in conditions of water stress. Despite their long-recognized role, little attention has been given to their development on waste rock slopes subject to rapid drainage. This study was conducted in an open-pit gold mine in a boreal forest. Its main objective was to establish a plantation design with a moderate level of competition for water resources on a waste rock slope. A hybrid poplar plantation was established in May 2013 on a soil-covered waste rock slope of 33%. The experimental design included three different poplar spacings: 1 × 1 m, 2 × 2 m without herbaceous seeding, 2 × 2 m with herbaceous seeding and 4 × 4 m. The poplars responded to increased competition resulting from closer spacing and herbaceous seeding by investing less energy in diameter and height growth. Poplar individuals that were subject to high levels of competition were able to acclimatize to water stress conditions by increasing root length density and specific root length and by reducing above-ground biomass. This study indicates that some clones of hybrid poplar showing phenotypic plasticity in the ratio of above- and belowground growth can be adapted for short-term revegetation of mine sites.

Elements of the ancient periglacial flora such as peat bog shrubs provide a paleorefugium in Central Europe for survival of glacial biota and other cold-adapted species during recent climate change. This study provides evidence that diversity of one of the most numerous consumers in peat bogs, beetles, was higher in mid-successional stages characterized by the highest degree of shrub encroachment, compared with early and old stages. The main autogenic factor driving successional changes of herb-shrub layer coleopteran assemblages were shrub cover and bog water level. Younger successional stages contained the highest abundance of herb dwellers (chortobionts) and polyphagous species, whereas middle and old stages contained shrub inhabitants (chamebionts), which are oligophagous species specializing on ericaceous dwarf shrubs. Species richness and abundance of cold-adapted inhabitants of peat bogs (tyrphobiontic and tyrphophilous) increased from young to old successional stages along with increased shrub cover. Herb dwellers and polyphagous species are among the first primary consumers to colonize peat bogs. With changes in late-successional habitats, in particular the invasion of ericaceous dwarf shrubs, chamebiontic and oligophagous species start colonizing.

Vocal signals are important in many animal species for communication, coordination, and pair bonding and are especially well studied in birds. In the Red Crossbill (Loxia curvirostra) calls are an important trait for mate choice. In this species, calls having the same function (e.g., flight calls or excitement calls) are known to be clustered in distinct groups, so called ‘call types'. Each individual utters only calls of one call type. The driving force for the differentiation of Red Crossbill call types in the Palearctic remains unknown, as call types often overlap in space, and time and birds can be seen feeding on the same seeds. In this study, we investigated calls of crossbills, recorded within seven years in the Western Palearctic. We found at least 17 distinct call types of Red Crossbill and at least two call types of Parrot Crossbill (Loxia pytyopsittacus). There were obvious differences in call type delimitation between the northern and southern part of the study area. We argue this is in conflict with the ecological differentiation hypothesis and propose that there are other or further driving forces for this differentiation process.