Biodiversity in Dead Wood Stokland, Jogeir N; Siitonen, Juha; Jonsson, Bengt Gunnar
04/2012
eBook, Book
Fossils document the existence of trees and wood-associated organisms from almost 400 million years ago, and today there are between 400,000 and 1 million wood-inhabiting species in the world. This ...is the first book to synthesise the natural history and conservation needs of wood-inhabiting organisms. Presenting a thorough introduction to biodiversity in decaying wood, the book studies the rich diversity of fungi, insects and vertebrates that depend upon dead wood. It describes the functional diversity of these organisms and their specific habitat requirements in terms of host trees, decay phases, tree dimensions, microhabitats and the surrounding environment. Recognising the threats posed by timber extraction and forest management, the authors also present management options for protecting and maintaining the diversity of these species in forests as well as in agricultural landscapes and urban parks.
1. Dead wood is a habitat for numerous fungal species, many of which are important agents of decomposition. Previous studies suggested that wood-inhabiting fungal communities are affected by climate, ...availability of dead wood in the surrounding landscape and characteristics of the colonized dead-wood object (e.g. host tree species). These findings indicate that different filters structure fungal communities at different scales, but how these factors individually drive fungal fruiting diversity on dead-wood objects is unknown. 2. We conducted an orthogonal experiment comprising 180 plots (0.1 ha) in a random block design and measured fungal fruit body richness and community composition on 720 dead-wood objects over the first 4 years of succession. The experiment allowed us to disentangle the effects of the host (beech and fir; logs and branches) and the environment (microclimate: sunny and shady plots; local dead wood: amount and heterogeneity of dead wood added to plot). 3. Variance partitioning revealed that the host was more important than the environment for the diversity of wood-inhabiting fungi. A more detailed model revealed that host tree species had the highest independent effect on richness and community composition of fruiting species of fungi. Host size had significant but low independent effects on richness and community composition of fruiting species. Canopy openness significantly affected the community composition of fruiting species. By contrast, neither local amount nor heterogeneity of dead wood significantly affected the fungal diversity measures. 4. Synthesis. Our study identified host tree species as a more important driver of the diversity of wood-inhabiting fungi than the environment, which suggests a hostcentred filter of this diversity in the early phase of the decomposition process. For the conservation of wood-inhabiting fungi, a high variety of host species in various microclimates is more important than the availability of dead wood at the stand level.
This book is a selection of manuscripts devoted to the conservation and preservation of wooden cultural heritage. The articles present the new methods for conservation of various historical wooden ...artefacts, reliable modern techniques for characterisation of the wood structure, properties and degree of degradation, and discusses problems and doubts related to all aspects of conservation and re-conservation of wooden cultural heritage. It contains both review and research papers to give the readers a broader picture of the problems and issues related to the conservation of wooden historical objects and structures. We need to remember that wooden cultural heritage is an integral part of our culture and history that define our humanity. We are obliged to protect it, save it from oblivion, and preserve it for future generations.
Wood is the most accessible and renewable material used by humankind during its history. Today, the consumption of wood exceeds all other known materials. The industry of various products made of ...wood grows continuously. This book reviews research on hydrothermal treatment and modification of wood in the drying and impregnation process; the decomposition of coarse woody debris as an important component of the carbon cycle and biodivesity of forest ecosystems; and the potential of agroforestry as a carbon sequestration strategy. Also discussed is the importance of fossil woods, types of preservation, and their significance in reconstructing the palaeo-climatology and paleo-environment of a region as well as the limitation in identifying the fossil woods.
The surface temperature of a drying wooden board is strongly related to the drying process. However, it is relatively difficult to determine the surface temperature accurately during drying. In this ...paper, an experimental setup for analyzing the wood surface during drying by thermal imaging as well as dry and wet-bulb temperature reference surfaces was tested. Spruce sapwood samples were dried in various climates and evaluated with respect to both mass loss and surface temperature. The experimental setup enabled both qualitative and quantitative analysis of the wood drying process. The results showed that thermal imaging enabled a detailed view of the drying progression. The distinct correlation between surface temperature and mass change showed that an accurate determination of a basic, often considered, and difficult-to-determine drying potential is possible.
Wood contains primary extractives, which are present in all woods, and secondary extractives, which are confined in certain wood species. Extractives in wood play a major role in wood-bonding ...processes, as they can contribute to or determine the bonding relevant properties of wood such as acidity and wettability. Therefore, extractives play an immanent role in bonding of wood chips and wood fibres with common synthetic adhesives such as urea-formaldehyde-resins (UF-resins) and phenol-formaldehyde-resins (PF-resins). Extractives of high acidity accelerate the curing of acid curing UF-resins and decelerate bonding with alkaline hardening PF-resins. Water-soluble extractives like free sugars are detrimental for bonding of wood with cement. Polyphenolic extractives (tannins) can be used as a binder in the wood-based industry. Additionally, extractives in wood can react with formaldehyde and reduce the formaldehyde emission of wood-based panels. Moreover, some wood extractives are volatile organic compounds (VOC) and insofar also relevant to the emission of VOC from wood and wood-based panels.
This Special Issue of Coatings presents the newest research outcome in the field of the enhancement of native wood properties through a wide range of chemical, biological, and physical agents. The ...broad spectrum of topics provides a comprehensive update regarding ongoing research in this field. Such a compilation can be an inspiration for the further development of multifunctional and sustainable coatings, revolutionizing the wood sector of the future.
Large wood is an important physical component of woodland rivers and significantly influences river morphology. It is also a key component of stream ecosystems. However, large wood is also a source ...of risk for human activities as it may damage infrastructure, block river channels, and induce flooding. Therefore, the analysis and quantification of large wood and its mobility are crucial for understanding and managing wood in rivers. As the amount of large‐wood‐related studies by researchers, river managers, and stakeholders increases, documentation of commonly used and newly available techniques and their effectiveness has also become increasingly relevant as well. Important data and knowledge have been obtained from the application of very different approaches and have generated a significant body of valuable information representative of different environments. This review brings a comprehensive qualitative and quantitative summary of recent advances regarding the different processes involved in large wood dynamics in fluvial systems including wood budgeting and wood mechanics. First, some key definitions and concepts are introduced. Second, advances in quantifying large wood dynamics are reviewed; in particular, how measurements and modeling can be combined to integrate our understanding of how large wood moves through and is retained within river systems. Throughout, we present a quantitative and integrated meta‐analysis compiled from different studies and geographical regions. Finally, we conclude by highlighting areas of particular research importance and their likely future trajectories, and we consider a particularly underresearched area so as to stress the future challenges for large wood research.
Key Points
We review critical questions which remain open regarding large wood dynamics
• Vulnerability to cavitation and conductive efficiency depend on xylem anatomy. We tested a large range of structure-function hypotheses, some for the first time, within a single genus to minimize ...phylogenetic ‘noise' and maximize detection of functionally relevant variation. • This integrative study combined in-depth anatomical observations using light, scanning and transmission electron microscopy of seven Acer taxa, and compared these observations with empirical measures of xylem hydraulics. • Our results reveal a 2 MPa range in species' mean cavitation pressure (MCP). MCP was strongly correlated with intervessel pit structure (membrane thickness and porosity, chamber depth), weakly correlated with pit number per vessel, and not related to pit area per vessel. At the tissue level, there was a strong correlation between MCP and mechanical strength parameters, and some of the first evidence is provided for the functional significance of vessel grouping and thickenings on inner vessel walls. In addition, a strong trade-off was observed between xylem-specific conductivity and MCP. Vessel length and intervessel wall characteristics were implicated in this safety-efficiency trade-off. • Cavitation resistance and hydraulic conductivity in Acer appear to be controlled by a very complex interaction between tissue, vessel network and pit characteristics.