Assessing the genetic structure of capercaillie (Tetrao urogallus) in Romania

Romania holds the most extensive mountain range with old-growth forests, in which both habitat surface and capercaillie (Tetrao urogallus) numbers are ones of the highest in Central and Eastern Europe. While previous genetic studies have found that the individuals located in different European mountain ranges are isolated and have highlighted that the species is declining. Here, we are aiming to assess the genetic structure of capercaillie in Romania by genotyping 137 samples collected in the field with 9 STR markers. Expected heterozygosity was 0.586, whereas observed heterozygosity values were 0.859. Population structure analyses indicated weak population differentiation and suggested that sufficient gene flow exists among individuals sampled in different mountain regions. We did not find evidence for a past genetic bottleneck. Our findings contain important information to wildlife managers to focus conservation efforts in areas such as Curvature Carpathians, which serve as a connectivity corridor to avoid eroding the extent or quality of habitat and to prevent further fragmentation.

The mycobiota of needles and shoots of silver fir (Abies alba Mill.) with symptoms of Herpotrichia needle browning in the Tatra Mts. (Poland)

The European silver fir (Abies alba Mill.) has the largest distribution area of all the European species of fir. It is the only species of this type found in the Carpathian Mts., including their highest range - the Tatras, where it constitutes one of the main components of lower montane forests. In certain sections of the Carpathian Mountains fir stands are affected by the competitive pressure of beech. This may be due to climate change, as well as biotic factors such as plant diseases. One such disease is Herpotrichia needle browning. The goal of the present research was to assess the occurrence of Herpotrichia needle browning in the Tatra National Park and determine the species composition of fungi colonizing symptomatic needles and shoots. Symptoms of the disease were observed across the entire research period, i.e., from May to mid-September 2019. They included the wilting of the needles with subsequent mycelial growth on the remains, as well as shoot deformation. The mycological analysis of the needles and shoots of A. alba resulted in the isolation of 22 fungal taxa. In the case of the needles and shoots, which showed symptoms of infection, the most frequent species of fungus was Sydowia polyspora (Bref. & Tavel) E. Müll., followed by Alternaria alternata (Fr.) Keissl. and Rhizosphaera macrospora Gourb. & M. Morelet. Herpotrichia needle browning seems to be triggered by a complex disease resulting from synergistic interaction of several fungal pathogens.

Selective thinning to enhance soil biodiversity in artificial black pine stands - what happens to mushroom fruiting?

As a man-induced disturbance of forest ecosystems, thinning may affect biodiversity and other related ecological functions including fungal dynamics. In this context, a multidisciplinary EU-Life project was established in 2014 to evaluate the application of selective thinning in two Pinus nigra plantations areas of the Apennines (Monte Amiata and Pratomagno, Tuscany Italy). Selective thinning had the aim to improve stands stability and growth rates, taking also into account the various components of soil biodiversity (flora, fungi, mesofauna, nematodes, microarthropods and bacteria). Here we present mushroom fruiting patterns previous to treatment in 2014 and the effect following the application of forest management (selective thinning and traditional thinning from below) in 2018. Boxplots were used to graphically represent intra and inter annual variations in species richness and abundance, while Principal Coordinates Analyses and multi-response permutation procedures based on Bray-Curtis dissimilarity matrix were applied to evaluate turnover in species composition before the management and after 4 years.

A significant reduction of fungal richness and abundance after 4 years thinning impact was lacking in both study areas, testifying a certain degree of resistance and/or resilience of mushroom fruiting to forest management-related anthropogenic disturbance. Considering each study site separately, Monte Amiata and Pratomagno did not show one uniform trend but differed significantly in their response to management: while in Pratomagno relevant inter-annual differences were present only in a few cases, an underlining significant variation both for species richness and abundance was registered in Monte Amiata for all treatment types among years (inter-annual variation) but not within each year (intra-annual variation). Only in Pratomagno turnover in species composition in selective thinning differed somewhat from the traditional treatment in 2018, showing that a process is underlying but still potentially masked by other variables. Due to the nature of macrofungi, a longer study period (more than 4 years post treatment impact) as well as the application of a more intense forest management, could be necessary to highlight and disentangle any possible trends in fungal fruiting in artificial stands.

Structural heterogeneity and old-growthness: A first regional-scale assessment of Sardinian forests

Mediterranean forests have been altered by several human activities. Consequently, relatively intact forests that have been unmodified by humans for a relatively long time (i.e., old-growth forests) are often reduced to isolated and fragmented stands. However, despite their high conservation value, little is known about their features and even presence several Mediterranean areas. First steps of their investigation are based on the identification of old-growth features such as amount of large‐size and old trees, tree species composition, canopy heterogeneity, occurrence and amount of deadwood. The Structural Heterogeneity Index (SHI) is commonly used to summarise features of old-growthness in one single value. Here, the SHI was derived for 68 plots included in 45 forest stands within the 4,297 km² of territory that is covered by forests in Sardinia. SHI values were affected by variables that are likely to be related to forest age and structural complexity, such as presence of cerambycids, canopy cover, forest layers, location and three old-growthness classes. Results confirm a high structural variability among forests with old-growth features, determined by the presence, or lack, of given living and deadwood features. Our findings identified, for the first time, most of the forest stands that need special protection in Sardinia for the presence of old-growth features. In this sense, the SHI was confirmed useful for improving their management and conservation, although more specific and deeper studies are necessary for better understanding their species composition and dynamics.