Words apart: Standardizing forestry terms and definitions across European biodiversity studies

Forest biodiversity studies conducted across Europe use a multitude of forestry terms, often inconsistently. This hinders the comparability across studies and makes the assessment of the impacts of forest management on biodiversity highly context-dependent. Recent attempts to standardize forestry and stand description terminology mostly used a top-down approach that did not account for the perspectives and approaches of forest biodiversity experts. This work aims to establish common standards for silvicultural and vegetation definitions, creating a shared conceptual framework for a consistent study on the effects of forest management on biodiversity. We have identified both strengths and weaknesses of the silvicultural and vegetation information provided in forest biodiversity studies. While quantitative data on forest biomass and dominant tree species are frequently included, information on silvicultural activities and vegetation composition is often lacking, shallow, or based on broad and heterogeneous classifications. We discuss the existing classifications and their use in European forest biodiversity studies through a novel bottom-up and top-driven review process, and ultimately propose a common framework. This will enhance the comparability of forest biodiversity studies in Europe, and puts the basis for effective implementation and monitoring of sustainable forest management policies. The standards here proposed are potentially adaptable and applicable to other geographical areas and could be extended to other forest interventions. Forest management Multi-taxon Terminology Silviculture Data harmonizationpublishedVersio

Management of dynamic forest functions based on carbon, nitrogen and water cycles

Waldökosysteme zeichnen sich durch vielfältige, wenngleich miteinander verbundene Waldfunktionen aus. In dieser Doktorarbeit wurden langfristige Dynamiken der Waldfunktionen 1.) Kohlenstoff- und Stickstoffspeicherung im Waldboden, 2.) Regulierung des Wasserhaushalts und der Schutzfunktion gegen Hochwässer, 3.) Waldproduktivität und 4.) Wohlfahrts- und Erholungsfunktion studiert. Die Auswirkungen von Waldbewirtschaftung, Waldwachstum und sich ändernden Wuchsbedingungen auf diese Waldfunktionen wurden für vier, durch Fichte, Buche oder Amerikanischen Amberbaum dominierte Wälder in Österreich und in Tennessee, USA mit Hilfe eines Pärchen-Vergleichs und prozessbasierter Ökosystem-Modellierung mit dem Model Biome-BGC untersucht. Die Ergebnisse zeigen, dass Plenterwälder im Vergleich zu schlagweise genutzten Altersklassenwäldern größere Mengen an Kohlenstoff und Stickstoff im Boden speichern und somit zur Erholung degradierter Böden beitragen. Für den Wienerwald wurde bis 2100 eine vom Klimaszenario abhängige gleichbleibende oder erhöhte Produktivität prognostiziert, wenngleich in den tieferen Lagen die Bodentrockenheit zukünftig einen limitierenden Faktor darstellen könnte. Die Fichtenwälder des Schmittentales zeigten eine deutliche Kontrolle des Abflussgeschehens, wobei bereits bei einem Holzvorrat ab 250 m3 sich der Wasserverbrauch auf hohem Niveau stabilisierte und somit eine entsprechende Schutzwirkung gegeben war. Wasserhaushalts- und Produktivitätsparameter zeigten insgesamt eine starke Abhängigkeit von Bestandesentwicklung, Baumart, atmosphärischem CO2-Gehalt, Temperatur- und Niederschlagsänderungen und Stickstoffeintrag. Mit Hilfe von Waldbewirtschaftung lässt sich somit bei Kenntnis der Ökophysiologie der Baumarten die Bereitstellung der untersuchten Waldfunktionen (beispielsweise Hochwasserschutz, Trinkwasserbereitstellung und Netto-Kohlenstoffbilanz als Faktor für den Klimaschutz) durch die Umtriebszeit, die Bestandesdichte und die Baumartenwahl steuern.Forest ecosystems are characterised by numerous different, but dependent forest functions. In this dissertation I investigated effects of forest management, stand development and changing growing conditions on the interrelated ecosystem pools and fluxes of carbon, nitrogen and water and derived effects on the following forest functions: 1.) Storage of carbon & nitrogen in the soil; 2.) Regulation of the water budget & flood protection; 3.) Productivity; 4.) Welfare & recreation. The long-term dynamics of these forest functions were studied in four different Norway spruce, European beech and American sweetgum dominated forests in different eco-regions in Austria and in Tennessee, USA using a paired-stand approach and mechanistic ecosystem modelling with the Biome-BGC model. Results showed that a management change from age class forests to single tree selection forests can increase soil carbon and nitrogen storage and therefore ameliorate degraded soils. Constant or increasing productivity and increasing water use efficiency were projected for the Vienna Woods until 2100, depending on the climate change scenario. Decreasing soil water potentials mainly in low elevations, however, could limit a future productivity increase. Simulations of Norway spruce forests in the Schmittental valley and the analysis of 29 years of river runoff data demonstrated that forest canopy development and ecophysiological control of transpiration change catchment runoff. With a standing timber volume of > 250 m3 outflow was minimised, supporting flood prevention. Consequently, forest management can regulate the provision of a diverse set of forest functions (e.g. flood protection, drinking water supply, net ecosystem carbon storage for climate change mitigation). Foresters can adjust rotation length, stand density and structure, and promote tree species with the desired ecophysiological behaviour, and with these measures influence the flux dynamics in forests.Elisabeth PötzelsbergerAbweichender Titel laut Übersetzung der Verfasserin/des VerfassersZsfassung in dt. SpracheWien, Univ. für Bodenkultur, Diss., 2015OeBB(VLID)193040

The Carbon Sequestration Potential of Degraded Agricultural Land in the Amhara Region of Ethiopia

Forests are a key player within the global carbon cycle and reforestation is an important climate change mitigation mechanism. In this study, we identify potentially suitable areas for reforestation to assess the carbon sequestration potential in the highly deforested and degraded Amhara region of Ethiopia. We apply biogeochemical mechanistic ecosystem modelling to predict the amount of carbon that can be potentially sequestered within different time horizons. Since human intervention plays a key role within the Amhara region, three different forest management scenarios and five different rotation periods following reforestation are tested: (i) unthinned; (ii) removal of 5% of the stem carbon every 20 years (thinning 1); and (iii) removal of 10% stem carbon every 20 years (thinning 2), as well as a rotation period of 10, 30, 50, 100, and 150 years. Sustainable management of reforested land is addressed by implementing the so called ‘Normal-forest’ system (equal representation of every age class). This ensures the long term sequestration effect of reforested areas. The study shows that 3.4 Mha (Mha = Million hectare) of land, including bare land (0.7 Mha), grass land (1.2 Mha), and shrub land (1.5 Mha) can be considered as ecologically potentially suitable for reforestation. Assuming a 100 year rotation period in a ‘Normal-forest’ system, this shows that a total net carbon sequestration potential of 177 Tg C (10.8 Tg C in the soil and 165.9 Tg C aboveground; Teragram = 1012 g) is possible, if all 3.4 Mha are replanted. The highest total net carbon sequestration (soil and aboveground) was evident for the Highland-wet agro-ecological zone, whereas the lowest values are typically in the Midland-dry zone. The highest net aboveground carbon sequestration was predicted for reforestations on current grass land and shrub land versus bare land, whereas the highest net soil carbon sequestration was predicted on current bare land, followed by grass land and shrub land

Genotypic data from 10 populations of Ailanthus altissima in Eastern Austria

The file contains genotypic data of 298 trees from 10 populations of Ailanthus altissima in eastern Austria. Samples were collected in the field and genotyped according to the methods described in the cited research. The file contains genotypes of five (5) microsatellite loci scored using fragment length analysis (Aa22, Aa69, Aa75, Aa76 and Aa82) and further twelve (12) microsatellite loci scored based on an SSR-GBS approach (loci loci HT2, HT7, HT9, HT10, HT16, HT19, HT22, HT24, HT27, HT30, HT31 and HT35). Genotypes of the same population assigned to a particular multilocus lineage (MLL) are marked with a capital letter (from A-F)

Mapping the patchy legislative landscape of non-native tree species in Europe

Artículo completo y materiales complementarios accesibles en el enlace siguiente: https://academic.oup.com/forestry/article/93/4/567/5850529Europe has a history rich in examples of successful and problematic introductions of trees with a native origin outside of Europe (non-native trees, NNT). Many international legal frameworks such as treaties and conventions and also the European Union have responded to the global concern about potential negative impacts of NNT that may become invasive in natural ecosystems. It is, however, national and regional legislation in particular that affects current and future management decisions in the forest sector and shapes the landscapes of Europe. We identified all relevant legal instruments regulating NNT, the different legal approaches and the regulatory intensity in 40 European countries (no microstates). Information on hard and effective soft law instruments were collected by means of a targeted questionnaire and consultation of international and national legislation information systems and databases. In total, 335 relevant legal instruments were in place in June/July 2019 to regulate the use of NNT in the investigated 116 geopolitical legal units (countries as well as sub-national regions with their own legislation). Countries and regions were empirically categorized according to ad hocdefined legislation indicators. These indicators pay respect to the general bans on the introduction of non-native species, the generally allowed and prohibited NNT, approval mechanisms and specific areas or cases where NNT are restricted or prohibited. Our study revealed a very diverse landscape of legal frameworks across Europe, with a large variety of approaches to regulating NNT being pursued and the intensity of restriction ranging from very few restrictions on species choice and plantation surface area to the complete banning of NNT from forests. The main conclusion is that there is a clear need for more co-ordinated, science-based policies both at the local and international levels to enhance the advantages of NNT and mitigate potential negative effects.Unión Europea - Programa COSTDepartamento de Ciencias Agroforestale

Data from: Population bottlenecks have shaped the genetic variation of Ailanthus altissima (Mill.) Swingle in an area of early introduction

Ailanthus altissima is a common tree species of the European non-native flora. In Eastern Austria, Ailanthus has both a long tradition, dating back to the late 18th century, and a high frequency of occurrence. Here, we apply molecular markers from the nuclear and chloroplast DNA in order to study the origin, as well as the clonal and genetic structure of the species in forest stands of this region. Our results indicate a single area of origin for all our study populations from the north-eastern part of the native range, in agreement with historical reports. Within populations, vegetative reproduction has resulted in extensive clonal structures at some sites. Long presence and repeated vegetative recruitment might have led to expansion of clones in areas of early introduction. In addition, limited mate availability may also have promoted vegetative reproduction. Tests for recent bottlenecks were significant in almost all stands, possibly reflecting founder effects since the introduction of Ailanthus in our study area. Among populations, we found a very pronounced and significant genetic structure, which did not follow a spatial pattern. We argue that founder effects due to population establishment with a low number of propagules – whether naturally or artificially – have caused genetic drift and a structured gene pool. The lack of spatial pattern or isolation-by-distance suggests that seed transfer by humans might have been a major factor shaping the genetic variation of Ailanthus in Eastern Austria

Growing Non-native Trees in European Forests Brings Benefits and Opportunities but Also Has Its Risks and Limits

Purpose of Review: Non-native tree species (NNT) raise a range of different associations and emotions—to many citizens they are just an exotic curiosity in parks, to many conservationists they are an evil to native ecosystems that should be eradicated, to a rising group of foresters they are part of the solution to climate change and an increasing timber demand, and to others they are already daily forestry business. In this review, where we also summarise the findings of the recent COST Action FP1403 (NNEXT) ‘Non-native tree species for European forests: experiences, risks and opportunities’, we highlight opportunities and challenges in the light of climate change, ecological risks and legislative limits of growing non-native tree species in Europe. Recent Findings: Few NNT in Europe show invasive behaviour and are listed as prohibited species or as species to be monitored. A larger number of NNT is utilised in productive forestry and forest restoration due to their superior growth, valuable timber properties and good performance under harsh growing conditions. Current species distribution, experiences with success and failures and environmental concerns differ profoundly across Europe, with Western Europe overall revealing higher shares in NNT and showing a stronger interest of forestry related stakeholder groups to continue planting NNT. Summary: Many more NNT are already used in forestry than previously thought, but relatively few species have major importance in terms of area, mainly in western European countries. Diversification, mixing and avoidance of invasion in relation to NNT are necessities that are relatively new on the agenda. In contrast, provenance research of major NNT has been going on for many decades and now provides important information for climate change adaptation. Despite the limitations to the use of NNT either through legal restrictions or forest certification that differ considerably across Europe, the careful integration of a range of tested NNT also into future forest management planning shows a high potential for climate change adaptation and mitigation

The incorporation of extreme drought events improves models for beech persistence at its distribution limit

International audience& Context Projections of species distribution models under future climate are usually based on long-term averages. However, singular extreme drought events presumably con-tribute to the shaping of distribution limits at the retreating low-elevation xeric limits. & Methods The objectives of this study were to set up a distribution model based on extreme drought events (EDM), which uses sanitary logging information as a proxy of vitality response of beech, and compare it with the results of classical species distribution models (SDMs). & Results Predictions of the EDM for 2025 were in agreement with those of the SDM, but EDM predicted a more serious decline in all regions of Hungary towards the end of the century. & Conclusion These results suggest that the predicted increase in frequency and severity of drought events may further limit the distribution of beech in the future

Extent, distribution and origin of non-native forest tree species in Europe

The management of non-native tree species in European forests has a long history, but the information on the current number and geographic distribution of these species in European forests is incomplete and scattered across various datasets. This study aims to perform an inventory of the most frequent non-native tree species growing in European forests and analyse their current extent, geographic distribution and geographic origin. Our results show that at least 150 nonnative tree species are currently growing in European forests and provenance trials. The genera represented by largest number of species are Eucalyptus, Pinus, Acacia and Abies. Species growing at the largest areas are Robinia pseudoacacia (2.44 million ha), Eucalyptus globulus (1.46 million ha), Picea sitchensis (1.16 million ha) and Pseudotsuga menziesii (0.83 million ha). In total, non-native tree species in Europe are found in an area of approximately 8.54 million ha, or 4.0% of the European forest area, and the %ve most abundant species account for up to 77% of this area. The largest number of these 150 species were introduced from North America (71), followed by Asia (45) and Australia (20). North American species occupy by far the largest area

Biotic threats for 23 major non-native tree species in Europe

For non-native tree species with an origin outside of Europe a detailed compilation of enemy species including the severity of their attack is lacking up to now. We collected information on native and non-native species attacking non-native trees, i.e. type, extent and time of first observation of damage for 23 important non-native trees in 27 European countries. Our database includes about 2300 synthesised attack records (synthesised per biotic threat, tree and country) from over 800 species. Insects (49%) and fungi (45%) are the main observed biotic threats, but also arachnids, bacteria including phytoplasmas, mammals, nematodes, plants and viruses have been recorded. This information will be valuable to identify patterns and drivers of attacks, and trees with a lower current health risk to be considered for planting. In addition, our database will provide a baseline to which future impacts on non-native tree species could be compared with and thus will allow to analyse temporal trends of impacts