Background
The importance of structurally diverse forests for the conservation of biodiversity and provision of a wide range of ecosystem services has been widely recognised. However, tools to ...quantify structural diversity of forests in an objective and quantitative way across many forest types and sites are still needed, for example to support biodiversity monitoring. The existing approaches to quantify forest structural diversity are based on small geographical regions or single forest types, typically using only small data sets.
Results
Here we developed an index of structural diversity based on National Forest Inventory (NFI) data of Baden-Württemberg, Germany, a state with 1.3 million ha of diverse forest types in different ownerships. Based on a literature review, 11 aspects of structural diversity were identified a priori as crucially important to describe structural diversity. An initial comprehensive list of 52 variables derived from National Forest Inventory (NFI) data related to structural diversity was reduced by applying five selection criteria to arrive at one variable for each aspect of structural diversity. These variables comprise 1) quadratic mean diameter at breast height (DBH), 2) standard deviation of DBH, 3) standard deviation of stand height, 4) number of decay classes, 5) bark-diversity index, 6) trees with DBH ≥ 40 cm, 7) diversity of flowering and fructification, 8) average mean diameter of downed deadwood, 9) mean DBH of standing deadwood, 10) tree species richness and 11) tree species richness in the regeneration layer. These variables were combined into a simple, additive index to quantify the level of structural diversity, which assumes values between 0 and 1. We applied this index in an exemplary way to broad forest categories and ownerships to assess its feasibility to analyse structural diversity in large-scale forest inventories.
Conclusions
The forest structure index presented here can be derived in a similar way from standard inventory variables for most other large-scale forest inventories to provide important information about biodiversity relevant forest conditions and thus provide an evidence-base for forest management and planning as well as reporting.
Abstract
Key message
Authors have analyzed the possible correlation between measurements/indicators of forest structure and species richness of many taxonomic or functional groups over three regions ...of Germany. Results show the potential to use structural attributes as a surrogate for species richness of most of the analyzed taxonomic and functional groups. This information can be transferred to large-scale forest inventories to support biodiversity monitoring.
Context
We are currently facing a dramatic loss in biodiversity worldwide and this initiated many monitoring programs aiming at documenting further trends. However, monitoring species diversity directly is very resource demanding, in particular in highly diverse forest ecosystems.
Aims
We investigated whether variables applied in an index of stand structural diversity, which was developed based on forest attributes assessed in the German National Forest Inventory, can be calibrated against richness of forest-dwelling species within a wide range of taxonomic and functional groups.
Methods
We used information on forest structure and species richness that has been comprehensively assessed on 150 forest plots of the German biodiversity exploratories project, comprising a large range of management intensities in three regions. We tested, whether the forest structure index calculated for these forest plots well correlate with the number of species across 29 taxonomic and functional groups, assuming that the structural attributes applied in the index represent their habitat requirements.
Results
The strength of correlations between the structural variables applied in the index and number of species within taxonomic or functional groups was highly variable. For some groups such as Aves, Formicidae or vascular plants, structural variables had a high explanatory power for species richness across forest types. Species richness in other taxonomic and functional groups (e.g., soil and root-associated fungi) was not explained by individual structural attributes of the index. Results indicate that some taxonomic and functional groups depend on a high structural diversity, whereas others seem to be insensitive to it or even prefer structurally poor stands.
Conclusion
Therefore, combinations of forest stands with different degrees of structural diversity most likely optimize taxonomic diversity at the landscape level. Our results can support biodiversity monitoring through quantification of forest structure in large-scale forest inventories. Changes in structural variables over inventory periods can indicate changes in habitat quality for individual taxonomic groups and thus points towards national forest inventories being an effective tool to detect unintended effects of changes in forest management on biodiversity.
Background
To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management ...for many forest owners and jurisdictions. At the same time, future harvesting intensity (HI) may increase to meet the demand for woody biomass by an increasing bioeconomy sector. Yet, the influence of HI on forest structural diversity is largely unknown. Here, we address this issue by analyzing the relationship between HI and structural diversity based on large-scale national forest inventory (NFI) data, where the latter is quantified using a previously developed
Forest Structure Index
and HI is expressed as wood volume removal during the period 2002–2012 for the same inventory plots.
Results
Our results show a surprisingly small impact of harvesting intensity on changes in structural diversity for most of the analysed types of forests. Only intense harvesting (> 80%–90% of initial growing stock) led to a significant reduction in structural diversity. At low to moderate HI most aspects of structural diversity were positively influenced. Only the quadratic mean DBH and the volume of large trees (≥ 40 cm DBH) were substantially negatively influenced at HI > 60% and 70% of initial growing stock, respectively.
Conclusions
In several forest types, HI could be increased without a reduction in overall structural diversity. Hence, structural diversity in these selectively managed forests appears to be a very resistant forest property in relation to HI. Other indicators at stand and landscape scale may be needed to adjust levels of HI that are suited to maintain forest biodiversity.
Retention forestry implies that biological legacies like dead and living trees are deliberately selected and retained beyond harvesting cycles to benefit biodiversity and ecosystem functioning. This ...model has been applied for several decades in even-aged, clearcutting (CC) systems but less so in uneven-aged, continuous-cover forestry (CCF). We provide an overview of retention in CCF in temperate regions of Europe, currently largely focused on habitat trees and dead wood. The relevance of current meta-analyses and many other studies on retention in CC is limited since they emphasize larger patches in open surroundings. Therefore, we reflect here on the ecological foundations and socio-economic frameworks of retention approaches in CCF, and highlight several areas with development potential for the future. Conclusions from this perspective paper, based on both research and current practice on several continents, although highlighting Europe, are also relevant to other temperate regions of the world using continuous-cover forest management approaches.
Background: To increase ecosystem resilience and biodiversity, the maintenance and improvement of structural and compositional diversity of forests has become an important goal in forest management ...for many forest owners and jurisdictions. At the same time, future harvesting intensity (HI) may increase to meet the demand for woody biomass by an increasing bioeconomy sector. Yet, the influence of HI on forest structural diversity is largely unknown. Here, we address this issue by analyzing the relationship between HI and structural diversity based on large-scale national forest inventory (NFI) data, where the latter is quantified using a previously developed Forest Structure Index and HI is expressed as wood volume removal during the period 2002–2012 for the same inventory plots. Results: Our results show a surprisingly small impact of harvesting intensity on changes in structural diversity for most of the analysed types of forests. Only intense harvesting (> 80％–90％ of initial growing stock) led to a significant reduction in structural diversity. At low to moderate HI most aspects of structural diversity were positively influenced. Only the quadratic mean DBH and the volume of large trees (≥ 40 cm DBH) were substantial y negatively influenced at HI > 60％ and 70％ of initial growing stock, respectively. Conclusions: In several forest types, HI could be increased without a reduction in overall structural diversity. Hence, structural diversity in these selectively managed forests appears to be a very resistant forest property in relation to HI. Other indicators at stand and landscape scale may be needed to adjust levels of HI that are suited to maintain forest biodiversity.
Background:The importance of structurally diverse forests for the conservation of biodiversity and provision of a wide range of ecosystem services has been widely recognised.However,tools to quantify ...structural diversity of forests in an objective and quantitative way across many forest types and sites are still needed,for example to support biodiversity monitoring.The existing approaches to quantify forest structural diversity are based on small geographical regions or single forest types,typically using only small data sets.Results:Here we developed an index of structural diversity based on National Forest Inventory (NFI) data of Baden Württemberg,Germany,a state with 1.3 million ha of diverse forest types in different ownerships.Based on a literature review,11 aspects of structural diversity were identified a priori as crucially important to describe structural diversity.An initial comprehensive list of 52 variables derived from National Forest Inventory (NFI) data related to structural diversity was reduced by applying five selection criteria to arrive at one variable for each aspect of structural diversity.These variables comprise 1) quadratic mean diameter at breast height (DBH),2) standard deviation of DBH,3) standard deviation of stand height,4) number of decay classes,5) bark-diversity index,6) trees with DBH ≥ 40 cm,7) diversity of flowering and fructification,8) average mean diameter of downed deadwood,9) mean DBH of standing deadwood,10) tree species richness and 11) tree species richness in the regeneration layer.These variables were combined into a simple,additive index to quantify the level of structural diversity,which assumes values between 0 and 1.We applied this index in an exemplary way to broad forest categories and ownerships to assess its feasibility to analyse structural diversity in large-scale forest inventories.Conclusions:The forest structure index presented here can be derived in a similar way from standard inventory variables for most other large-scale forest inventories to provide important information about biodiversity relevant forest conditions and thus provide an evidence-base for forest management and planning as well as reporting.
In acidified forest soils, the coarse‐soil fraction is a potential nutrient source. Plant nutrient uptake from the coarse‐soil fraction is aided by ectomycorrhiza. Similarly, (recalcitrant) organic ...matter (OM) is an important nutrient source largely made plant‐available through (symbiotic) microorganisms, especially in the topsoil. We hypothesized that in a podzol profile, fungal hyphae would concentrate in nutrient hotspots, either OM or the coarse‐soil fraction. Absolute hyphal length, base saturation, and organic‐C content of a Podzol profile were determined in the fine‐earth and coarse‐soil fractions. In the fine‐earth fraction, hyphae were attracted by the organic‐C content and relative high base saturation. In the coarse‐soil fraction of the BhBs horizon, the absolute hyphal length exceeded the hyphal length in the fine earth by factor 3, yet C content and base saturation were lowest. We could not determine to what fungi the hyphae belonged. Most likely ectomycorrhiza, ericoid mycorrhiza and saprotrophic fungi dominate the upper soil layers of this profile and all utilize OM for nutrition. In the deeper mineral horizons and especially in the coarse‐soil fraction, ectomycorrhiza are better adapted than other fungi to harvest nutrients from inorganic sources. Additionally, favorable physical properties may explain the high amount of fungal hyphae in the coarse‐soil fraction of the BhBs horizon. Both the coarse‐soil fraction and deeper mineral soil horizons may play a more active role in microbial nutrient cycling than previously assumed.
Am 2. und 3. November 2021 trafen sich in Braunschweig Fachleute aus der waldbezogenen Biodiversitätsforschung und dem Monitoring, um fundierte Ideen und Vorschläge zur Erstellung eines nationalen ...Biodiversitätsmonitorings im Wald (NaBioWald) zu sammeln und einen Überblick über das diesbezügliche Meinungsspektrum zu erlangen. Impulsreferate zeigten Ansprüche, Potenziale und Grenzen bestehender und neuer Walderhebungen in Deutschland aus Sicht der Waldpolitik, dem Nationalen Monitoringzentrum zur Biodiversität (NMZB), den Forstlichen Versuchsanstalten und der Schweiz, die bereits auf Erfahrungen eines etablierten Biodiversitätsmonitorings zurückgreifen kann. In den Fachdiskussionen wurden die möglichen Voraussetzungen, Erfolgsfaktoren, Barrieren und Methoden, sowie das potentielle Erfassungsdesign eines nationalen Biodiversitätsmonitorings im Wald diskutiert. Es wurden Entwicklungsoptionen und Lücken bestehender Flächennetze/Erhebungen analysiert und Akteure für die Qualitätssicherung und Akzeptanz der Konzeption definiert. Ein Monitoring ist notwendig und soll repräsentativ und robust relevante Entwicklungen der verschiedenen Ebenen der Biodiversität aufzeigen. Es soll bestehende nationale Walderhebungen einbinden, andere Erhebungen zur Biodiversität ergänzen sowie die aus ihnen resultierenden Erkenntnisse nutzen und - wo notwendig - neue Erhebungen integrieren. Neben der Biodiversität selbst sollen auch natürliche und anthropogene Einflussgrößen ('Treiber') erfasst werden. Genutzt werden soll es für ein biodiversitätsorientiertes Waldmanagement, für die Politik(-beratung) und Maßnahmensteuerung des Bundes und der Länder und für die Erfüllung von Berichtspflichten. Das Biodiversitätsmonitoring benötigt langfristig gesicherte Ressourcen und klare Verantwortlichkeiten. Als nächstes Ziel soll ein NaBioWald-Konzept ausgearbeitet werden. Die Monitoringaufgabe ist wegen der Komplexität, des Aufwands und der großen räumlichen Abdeckung von Bund und Ländern nur gemeinsam un
Chemokines critically control the infiltration of immune cells upon liver injury, thereby promoting hepatic inflammation and fibrosis. The chemokine receptor CCR8 can affect trafficking of ...monocytes/macrophages, monocyte‐derived dendritic cells (DCs) and T‐helper cell (Th) subsets, but its role in liver diseases is currently unknown. To investigate the functional role of CCR8 in liver diseases, ccr8−/− and wild‐type (WT) mice were subjected to chronic experimental injury models of carbon tetrachloride (CCl4) administration and surgical bile duct ligation (BDL). CCR8 was strongly up‐regulated in the injured liver. Ccr8−/− mice displayed attenuated liver damage (e.g., ALT, histology, and TUNEL) compared to WT mice and were also protected from liver fibrosis in two independent injury models. Flow cytometry revealed reduced infiltrates of liver macrophages, neutrophils and natural killer cells, whereas hepatic CD4+ T cells increased. The main CCR8‐expressing cells in the liver were hepatic macrophages, and CCR8 was functionally necessary for CCL1‐directed migration of inflammatory but not for nonclassical monocytes into the liver. Moreover, the phenotype of liver macrophages from injured ccr8−/− animals was altered with increased expression of DC markers and enhanced expression of T‐cell‐attracting chemokine macrophage inflammatory protein 1‐alpha (MIP‐1α/CCL3). Correspondingly, hepatic CD4+ T cells showed increased Th1 polarization and reduced Th2 cells in CCR8‐deficient animals. Liver fibrosis progression, but also subsequent T‐cell alterations, could be restored by adoptively transferring CCR8‐expressing monocytes/macrophages into ccr8−/− mice during experimental injury. Conclusions: CCR8 critically mediates hepatic macrophage recruitment upon injury, which subsequently shapes the inflammatory response in the injured liver, affecting macrophage/DC and Th differentiation. CCR8 deficiency protects the liver against injury, ameliorating initial inflammatory responses and hepatic fibrogenesis. Inhibition of CCR8 or its ligand, CCL1, might represent a successful therapeutic target to limit liver inflammation and fibrosis progression. (Hepatology 2012)
Exhaust regulations and improved exhaust gas treatment systems have already initiated the trend that brings emissions from brakes and tires to the forefront of traffic-induced particulate matter. The ...health and environmental relevance of particulate matter has resulted in regulators, industry, and research institutions prioritising the mitigation of non-exhaust particle emissions. To this end, under the umbrella of the United Nations Economic Commission for Europe World Forum for Harmonisation of Vehicle Regulations (UNECE WP.29), the Working Party on Pollution and Energy (GRPE) mandated the Particle Measurement Programme Informal Working Group (PMP-IWG) to develop a Global Technical Regulation (GTR) for measuring brake dust. The standards and procedures defined within the GTR should eventually form the basis for the introduction of a Euro 7 limit value for brake emissions. The purpose of this measurement campaign is to provide an exemplary overview of the emission behaviour of wheel brakes and friction pairings currently available on the market and to identify possible reduction potential with regard to particulate emissions. All measurements were carried out taking into account the draft GTR valid at the time of execution. For the investigations, brakes were selected using the example of different vehicle classes, brake concepts (disc and drum brake), vehicle axles (front and rear axle), and alternative friction materials (brake disc and pads/shoes). Thus, the use of wear-resistant discs and improved brake pad compositions are able to achieve significantly lower emissions. In addition, the measurement of brake dust emissions from vehicles with different levels of electrification was considered. Electrical braking was modelled and applied to the Worldwide Harmonised Light-Duty Vehicles Test Procedure (WLTP) Brake Cycle, which has demonstrated high emission reduction potentials depending on the electrification level.
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