Stand Composition, Tree-Related Microhabitats and Birds—A Network of Relationships in a Managed Forest

Forest ecosystems contain many tree-related microhabitats (TreMs), which are used by various groups of organisms. Birds use TreMs for shelter, foraging and breeding. The abundance and variability of TreMs is related to tree stand composition and age. Over the last few centuries there has been a drastic decline in the structural and biological diversity of temperate forests over large areas of the Northern Hemisphere. These changes have reduced the diversity and quantity of TreMs. In this study we showed the relationships between stand composition, the abundance of TreMs, and the species richness of birds in a managed forest. We focused on TreMs that are important to birds: woodpecker breeding cavities, rot holes, dead branches, broken treetops, and perennial polypores. Our study was performed in a managed lowland temperate forest. In 94 plots (10 ha each) we made bird surveys and inventoried the stand composition and TreMs. Our results show that the tree stand composition of a managed forest affects the abundance of TreMs. The share of deciduous trees in the stand favors the occurrence of such TreMs as dead branches, rot holes and perennial polypores. The overall richness of bird species and the species richness of primary cavity nesters depended on the total basal area of oak, hornbeam and birch, whereas the species richness of secondary cavity nesters increased with the total basal area of birch and oak.

The Tracking and Frequency Measurement of the Sway of Leafless Deciduous Trees by Adaptive Tracking Window Based on MOSSE

The tree sway frequency is an important part of the dynamic properties of trees. In order to obtain trees sway frequency in wind, a method of tracking and measuring the sway frequency of leafless deciduous trees by adaptive tracking window based on MOSSE was proposed. Firstly, an adaptive tracking window is constructed for the observed target. Secondly, the tracking method based on Minimum Output Sum Of Squared Error Filter (MOSSE) is used to track tree sway. Thirdly, Fast Fourier transform was used to analyze the horizontal sway velocity of the target area on the trees, and the sway frequency was determined. Finally, comparing the power spectral densities (PSDs) of the x axis acceleration measured by the accelerometer and PSDs of the x axis velocity measured by the video, the fundamental sway frequency measured by the accelerometer is equal to the fundamental sway frequency measured by video. The results show that the video-based method can be used successfully for measuring the sway frequency of leafless deciduous trees.

Распределение механических свойств древесины лиственных пород в годовых кольцах, выявленных методом сканирующего наноиндентирования

The paper presents the results of mechanical properties scanning by means of nanoindentation across the annual growth rings of deciduous trees wood, small-leaved lime (Tilia cordata) and common oak (Quercus robur) in particular. Significant variations in microhardness H and Young’s modulus E radial dependencies have been found for any of the studied species. Results can be useful 1) to amend the understanding the nature of macromechanical properties of various wood species and to reveal the details of their formation depending upon microstructural characteristics, 2) to optimize the technologies of growing, reinforcement and subsequent usage of the wood, 3) to develop new independent methods in dendrochronology and dendroclimatology

Robust forest cover indices for multispectral images

Trees occur in many land cover classes and provide significant ecosystem services. Remotely sensed multispectral images are often used to create thematic maps of land cover, but accurately identifying trees in mixed land-use scenes is challenging. We developed two forest cover indices and protocols that reliably identified trees in WorldView-2 multispectral images. The study site in Maryland included coniferous and deciduous trees associated with agricultural fields and pastures, residential and commercial buildings, roads, parking lots, wetlands, and forests. The forest cover indices exploited the product of either the reflectance in red (630 to 690 nm) and red edge (705 to 745 nm) bands or the product of reflectance in red and near infrared (770 to 895 nm) bands. For two classes (trees versus other), overall classification accuracy was >77 percent for the four images that were acquired in each season of the year. Additional research is required to evaluate these indices for other scenes and sensors.

Root Growth Dynamics and Structure in Seedlings of Four Shade Tolerant Mediterranean Species Grown under Moderate and Low Light

Specific functional traits such as shade tolerance or leaf habits can enhance root growth dynamics and structure of planted seedlings in the understory of planted forests. We assessed how low and moderate light levels (17 and 33% of full sunlight, mimicking after-thinning stocking) affect the root growth dynamics and structure of four late successional trees, three deciduous (Acer monspessulanum L., Quercus pyrenaica Willd and Sorbus torminalis (L.) Crantz) and one evergreen (Quercus ilex L.) species. Rooting depth, dynamics and structure were mainly explained by species functional differences. Roots of deciduous trees elongated faster and deeper and were larger than the roots of the evergreen Q. ilex. Among deciduous trees, S. torminalis had the lowest root growth. Specific leaf area and nutrient concentration were positively related to root growth, highlighting the importance of traits related to the plant economic spectrum, as determinants of species root growth differences. Moderate light level slightly enhanced root growth and decreased the specific leaf area (SLA). Species differences in water potential under drought were positively related to rooting depth, evidencing the importance of its role in overcoming drought stress during seedling establishment. These findings can guide the selection of late successional, shade tolerant tree species for underplanting thinned Mediterranean plantations and provide insights into their ecology.

A COMPARISON OF METABOLITES IN WOOD-FORMING TISSUES FROM EIGHT COMMERCIAL TIMBER TREE SPECIES OF HEILONGJIANG PROVINCE IN CHINA

Four coniferous and four deciduous commercial tree species from Northeastern ofChina were selected to investigate the differences ofmetabolites in wood-forming tissues bygas chromatography-mass spectrometry. The results showed that the identified metabolites mainly consisted of neutral sugars, lipids, and organic acids. The mean contents of both arabinofuranose and 1-cyclohexene-1-carboxylic acid were higher in coniferous trees thanin deciduous ones. Similarly, the D-fructose and D-glucose content was significantly higherin coniferous trees than deciduous trees, but the total contents of these two sugars was roughly equal among most tree species. The mean content of lactic acid, glycerol and malic acid was lowerin coniferous trees than deciduous trees. The malic acid content decreased in later-stages of wood formation than in early-stagefor all tree species. The content of L-proline and myo-inositol was greater in later-stage of wood formation than early-stage.The contentof octadecanoic acid, D-fructose and D-glucose decreased in later-stage of wood formationfor most tree species. All of thissuggested that the metabolites in wood-forming tissues showed the significance of species-specific and seasonal dynamic differences among the eight tree species.

FIRST REPORT OF GEOSMITHIA PALLIDA AND G. LANGDONII ASSOCIATED WITH LIPARTHRUM COLCHICUM IN CENTRAL ITALY

Bark and wood-boring beetles feeding on coniferous and deciduous trees in different forest ecosystems are often associated with various species of fungi. In 2019, widespread attacks of Liparthrum colchicum Semenov (Coleoptera Curculionidae Scolytinae) were observed on Laurus nobilis L. in Tuscany (Italy). Samples of colonized terminal twigs were collected to investigate the presence of phytopathogenic fungi associated with the scolytid. Two different colonies of the Geosmithia genus were identified as Geosmithia pallida and Geosmithia langdonii. To our knowledge this is the first report of G.pallida and G. langdonii associated with L. colchicum on Bay tree, in Italy.

How Young is a 300-Year-Old Wetland? The Case of the Pantanal Marimbus, Chapada Diamantina, Brazil

The Chapada Diamantina, in Northeastern Brazil, is one of the few places where one can find drylands with a backswamp containing hundreds of dead deciduous trees in the floodplain. During the 18th century, the region was globally important due to the exploration of mineral resources. The death of these trees was caused by mining activities that silted the main river, leading to the impoundment of the tributary river, and resulting in a wetland known as Pantanal Marimbus, having as indicators: (i) backswamp morphological feature that remains permanently flooded in the axis of the fluvial course, and (ii) alluvial fans concentrated in one footslope area where mining activities at the Chapada Diamantina were also concentrated. The hydrological and sedimentological behavior was investigated to multi-methods. By analysing four different samples from the bark and core of the same tree, we obtained calibrated radiocarbon dates within the 18th century. For no robust dendrochronology could be performed, a simple sequence model was built, revealing a high probability that the tree lived until approximately 1700 AD. 14C-AMS measured pioneering possible to evaluate the 300-years-old wetlands juvenile evolutionary state.