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ZusammenfassungDer primäre Verschluss großer Makulaforamina ist nach wie vor eine Herausforderung, wobei verschiedene Varianten einer Operation mit einem inversen Lappen der Membrana limitans interna (MLI) beschrieben worden sind. In der vorliegenden retrospektiven interventionellen Fallserie eines einzelnen Zentrums präsentieren wir eine Lappentechnik mit minimaler postoperativer Lagerung. Acht Augen von 8 Patienten (4 Frauen und 4 Männer) unterzogen sich im Zeitraum zwischen Juli 2020 und März 2022 einer von demselben erfahrenen Chirurgen (FMH) durchgeführten 23-G-3-Port-Vitrektomie mit einem umgekehrten MLI-Lappen und einer 20%igen SF6-Endotamponade für ein durchgreifendes Makulaloch. Sieben Makulaforamina wurden als groß (> 400 µm) und eines als mittelgroß (250 – 400 µm) eingestuft. Der mittlere minimale Durchmesser betrug 638,0 µm ± 166,4 µm (Bereich: 353 – 851 µm). Der Verschluss des Makulaforamens wurde bei allen Patienten (8/8, 100%) mit einem einzigen Eingriff erreicht. Der mediane bestkorrigierte Visus (BCVA) verbesserte sich von 6/120 (Snellen; Bereich: Fingerzählung [FC]) bis 6/19) präoperativ auf 6/19 (Bereich: FC bis 6/9,5) nach der Operation ohne intra- oder postoperative Komplikationen. Die Technik des superioren invertierten MLI-Lappens scheint ein sicherer und erfolgreicher Ansatz für den primären Verschluss großer Makulaforamina zu sein. In weiteren Studien sollte die von uns vorgeschlagene Operationstechnik an einer größeren Population untersucht werden, möglicherweise als Weiterentwicklung ohne Einsatz einer Luft- oder Gasendotamponade.

Primary closure of large macular holes remains challenging, and variations of inverted inner limiting membrane (ILM) flap surgery have been described. In the present retrospective, interventional, single-centre case series, we propose a superior flap design with minimal posturing. Eight eyes of eight patients (four women and four men) in the period between July 2020 and March 2022 underwent 23 G three-port vitrectomy with a superior inverted ILM flap and 20% SFDer primäre Verschluss großer Makulaforamina ist nach wie vor eine Herausforderung, wobei verschiedene Varianten einer Operation mit einem inversen Lappen der Membrana limitans interna (MLI) beschrieben worden sind. In der vorliegenden retrospektiven interventionellen Fallserie eines einzelnen Zentrums präsentieren wir eine Lappentechnik mit minimaler postoperativer Lagerung. Acht Augen von 8 Patienten (4 Frauen und 4 Männer) unterzogen sich im Zeitraum zwischen Juli 2020 und März 2022 einer von demselben erfahrenen Chirurgen (FMH) durchgeführten 23-G-3-Port-Vitrektomie mit einem umgekehrten MLI-Lappen und einer 20%igen SF

The storage of significant amounts of timber from thrown or dead trees after natural disturbances is an established practice for forest enterprises. Timber storage mitigates economic losses caused by supply-driven timber price falls after natural disturbances. We use a forest accounting database to explore the controls of residence times of coniferous timber stocks in storage following severe storm events. We characterize forest enterprises’ timber stock outflow distributions from storage over several years by mean residence times and their variances. We conduct regression analyses on the expected residence times and their variances. We assess the significance of several explanatory variables representing economic, institutional and tree species-related factors on these metrics using multiple linear regression analyses. Illustrating the effect of these variables on timber storage residence time distributions we reanalyze the database by grouping the FADN data sets with regard to the identified control variables and determine their mean timber storage outflow distributions after the storm events as well as associated expected residence times and their variances. Applying the resulting parameters with the continuous gamma distribution to simulate TSO residence time distributions clearly illuminates the effect of the control variables on storage management. We show that besides market price dynamics, species groups, ownership categories and forest worker capacities are statistically significant controls for mean residence times of timber stock in storage and their variances. We find that stronger timber price falls correlate with shorter mean residence times of timber stocks in storage. We relate this to liquidity maintenance of forest enterprises. We model duration times parameterizing the Gamma distribution. The application of the Gamma distribution to characterize storage management behavior offers the potential to describe differences in timber stock quantities even on shorter timescales than the mean storage residence times. According to our results, we propose to assess timber stocks in storage over a multi-year period in order to improve related national and international accounting schemes.

To provide an overview of biologics that are used to treat noninfectious uveitis, including their different targets, modes of actions, and indications.A review of recent and well-established literature was used to present the biochemical and pathophysiological background of biologics and to provide an account of evidence-based decision making for their use, not only in noninfectious uveitis in general, but with special regard to indications for their use in particular types of uveitis.Extensive clinical data for adalimumab shows that it is currently the only approved biologic for the treatment of uveitis. However, there is sufficient evidence to argue that many other biologics, notably TNF-α inhibitors, certain Interleukin inhibitors, Interferons, and B cell and T cell inhibitors, are also suitable for use in uveitis.Biologics have revolutionized the treatment of noninfectious uveitis and are now considered indispensable. They are used in cases of insufficient response to or intolerance of conventional immunosuppressive agents. However, they can also be indicated as a first-line therapy for certain types of uveitis (e.g., Behçet's disease). TNF-α inhibitors are the most commonly used biologics in the treatment of uveitis.Ziel dieser Zusammenfassung ist das Vermitteln einer Übersicht zu den verschiedenen Ansatzpunkten, Wirkmechanismen und Indikationen diverser Biologika, die bei der Therapie der nichtinfektiösen Uveitis zum Einsatz kommen.Etablierte sowie aktuelle Literatur wurden herangezogen, um die biochemischen und pathophysiologischen Grundlagen sowie eine evidenzbasierte Empfehlung zum Therapieeinsatz verschiedener Biologika bei nichtinfektiöser Uveitis allgemein und bei speziellen Uveitisentitäten darzulegen.Für viele Biologika, hier nennenswert TNF-α-Inhibitoren, einige Interleukininhibitoren, Interferone sowie B- und T-Zell-Inhibitoren, liegen mittlerweile gute Daten vor, was ihren Einsatz in der Uveitistherapie mehr als rechtfertigt. Dies trifft insbesondere für den TNF-α-Inhibitor Adalimumab zu, welcher der einzig zugelassene Vertreter für diese Indikation unter den vorgestellten Biologika ist.Die Biologika haben die Behandlung der Uveitis revolutioniert und sind aus der aktuellen Therapie der intraokularen Entzündung nicht mehr wegzudenken. Biologika werden bei Ineffektivität oder Unverträglichkeit konventioneller immunsuppressiver Medikamente empfohlen, aber auch bei der Therapie von schwerwiegenden Uveitisformen (z. B. Morbus Behçet). Die TNF-α-Inhibitoren sind die am häufigsten verwendeten Biologika bei Uveitis.

The EU Biodiversity Strategy (EUBDS) for 2030 aims at regaining biodiversity by strengthening the protection of nature in the European Union. This study models and analyses possible impacts of the EUBDS on the production and trade of forest-based products in the EU and non-EU countries in two alternative scenarios. Implementing EUBDS measures would allow a maximum EU roundwood production of roughly 281 M m3 in 2030 in the intensive and 490 M m3 in the moderate scenario. Since in the reference scenario, the EU roundwood production amounts to 539 M m3 in 2030, this represent a reduction of −48% and −9% in 2030, respectively. Until 2050, the production further decreases and accounts for 42% and 90% of the reference production. Globally, the EU roundwood production deficit is compensated partly (roughly between 50%–60%) by increasing production of roundwood in non-EU countries (e.g., USA, Russia, Canada, China and Brazil) whereas the remaining share of the EU production deficit is no longer produced and consumed worldwide. In the EU, reduced roundwood availability leads to a lower production of wood-based products, although, apparent consumption of wood-based products remains similar. This is mainly caused by significantly lower export volumes of wood-based products and, for some product groups, by significantly increased imports as well. This is partly due to unchanged assumptions regarding income and thus, demand patterns. However, on a global level, decreased production and consumption of wood-based products could lead to a growing use of non-bio-based resources to substitute wood-products. Our study also shows that the magnitude of effects strongly depends on how much the use of forest resources is actually restricted.

In recent years, several studies have found indications for data gaps and errors in the forestry production and trade section of the widely used FAOSTAT database. This manuscript focusses on inconsistencies in data on recovered pulp production, which have not yet been investigated in much detail. We develop national wood fiber balances for the pulp and paper sector for eleven countries. Our balances compare the wood fiber input (i.e. virgin and recovered pulp) in the paper and paperboard sector with the output (i.e. paper products) of this sector. By doing so, we are able to identify data gaps and errors and to determine the recovered pulp production as a residual volume in each country. For instance, we calculate a recovered pulp production of about 8.9 million tons for India in 2018. According to FAOSTAT, this production amounted to only 1.2 million tons. This is obviously too low considering that in the same year an apparent consumption of recovered paper of more than 10.1 million tons was reported. Moreover, we calculate ratios between virgin and recycled fibers in the paper production of the investigated countries. Our analysis provides a basis for better understanding of material flows in the pulp and paper sector and for supplements of international statistics.

The objective of this study is to assess the costs and the carbon sequestration potential of selected forest management measures in Germany, including effects on the harvested wood products (HWP) pool. We consider five different scenarios, each referring to an alternative level of wood harvests (due to changing rotation lengths or setting forest areas aside). The cost calculation is done within a framework that accounts for both financial impacts on downstream industries and impacts on the values of non-market goods and services of forests. To gauge the market-based costs of the scenarios in the national forest-based industries, different input-output methodological concepts are combined and applied in a novel fashion. A physical input-output table (PIOT) that shows the wood-based fiber flow through the forest-based industries of Germany forms the core of the model. The market-based costs of the mitigation measures are estimated as the aggregate of the value added losses in the German forest-based industries. Additionally, we include monetary value estimates of environmental costs and benefits based on a comprehensive choice experiment at the national level.

In a growing bioeconomy, traditional forest products markets change and diversify. Fossil-based inputs in the chemical, textile, apparel and downstream industries can be replaced by lignocellulose-based products such as dissolving pulp, cellulose-based chemical derivatives and textile fibres. When looking ahead, these previous niche products are likely to gain in economic importance. So far, little attention has been paid to the characteristics of macroeconomic relations of emerging lignocellulose-based materials on macroeconomic level. Key economic parameters for such materials are not available neither at regional nor at global level. This work aims to contribute to a better understanding of the market behavior of emerging forest products that are not yet covered by forest products market analysis. Therefore, this paper investigates how lignocellulose-based products respond to changes of main economic drivers and compute global market elasticities for dissolving pulp, cellulose-based chemical derivatives and textile fibres. To conduct our evaluation, we first test historical input data for non-constancy in time series due to structural changes using change-point estimator (MOSUM test). We subsequently carry out a global econometric analysis of demand and supply elasticities with income (GDP) and real import and export prices as explanatory variables. By doing so, we deliver key information for the adaptation of forest-product market analysis and modelling to an upcoming bioeconomy. The results show several structural changes especially in price data between 1992 and 2015, thus supporting the use of time series cuts to divide the time line from 1992 to 2015 into three different sub-periods. Elasticities are subsequently estimated for each of the sub-periods. The results from this econometric analysis provide import demand and export supply elasticities of dissolving pulp, cellulose chemical derivatives and cellulose textile fibres. In addition, we present elasticity estimation for the apparent consumption of dissolving pulp. Our findings outline the significant relationship between both export supply and import demand volumes and relative changes in prices and income. Across time periods, elasticities of cellulose-based derivatives and textile fibres do not show a clear trend towards more elastic or inelastic coefficients. However, the price elasticities of dissolving pulp fluctuate strongly from inelastic to highly elastic over time. Elasticity estimates of export supply indicate that it is sensitive to international competitiveness which in turn is governed by international demand. Finally, we statistically show that the estimated price and income elasticities of import demand can be analogously interpreted as the demand elasticity of apparent consumption. This is of great importance for economic equilibrium models, such as GFPM or EFI- GTM, in order to simulate and analyze forest sector developments and scenarios.

Environmental and economic accounting for forests: feasibilities and limits The European Parliament and the Council of the Member States of the European Union point out the need to further develop a system of environmental accounts, including physical and monetary accounts for natural capital and ecosystem services. For the forestry sector such a system already exists. The European framework for integrated environmental and economic accounting for forests (IEEAF) consists of a series of logically ordered tables. Basically it shows the flow of wood from the forest to the different intermediate and final use purposes in a consistent manner. Supplementary, IEEAF provides tables that present production and generation of income in the forestry sector, inform about defoliation, and show the key figures on forest carbon balances. The economic key figures of IEEAF are broadly in accordance with the European system of national accounting, and hence comparable with the respective overall economic key figures. In contrast, ecological indicators are not yet appropriately developed. Hence, ecosystem services on the whole are insufficiently accounted for. Provision with wood as well as carbon sequestration are the only ecosystem services which are covered rather comprehensively. Table systems or at least appropriate indicators for other ecosystem services like water purification and fresh water supply, biodiversity or recreation in forests are missing and deserve recording in the IEEAF framework. Natural capital and its ecosystem services on the whole can hardly be meaningfully evaluated in monetary terms. Changes, though, can. For this purpose it would be sufficient to include above mentioned ecosystem services into the IEEAF in physical terms only. Monetary evaluations could then be conducted for the changes of the services between the individual years.

In recent years, it has become increasingly popular to consider the forest-based industries as a so-called cluster. The forest cluster includes forestry enterprises as well as a wide range of industries, all engaged in the processing and manufacturing of roundwood as well as of semifinished and finished wood, pulp and paper products. The purpose of this paper was to depict the inter-industry linkages of the German forest cluster with the help of an input–output table. In the past, it was often the case that the various interactions between the different industries of the forest cluster were not fully perceived by industry managers, governmental bodies or associations, probably due to the distorted representation of the forest-based industries in official statistics. In this sense, the present study aimed at providing crucial baseline information for the understanding of this still rather fragmented sector. The disaggregated input–output table shows the various flows of inputs (measured in monetary values) into the productive process and matches them with outputs. Moreover, two exemplary impact analyses are conducted.

This paper presents a physical input-output table (PIOT) that shows the complete wood and paper flow through the economic system of Germany. The PIOT illustrates the wood and paper flow between different sectors and to different types of final use. It can be used both as a monitoring instrument and for scenario analysis. The hypothetical extraction method is applied in order to assess inter-industry linkages and single out key industries. Despite the wide variety of wood-based products and the versatile use of wood, it turns out that there is a surprisingly linear organization of the production system when it comes to the flow of wood and paper through Germany (“throughput economy”).

Both in Germany and in China, there is strong expertise regarding the different aspects of forest management, as well as forest products management. Nevertheless, forestry in both countries is facing challenges, some of which are regional, but many of which are shared. Therefore, experts from both countries (Technical University of Munich Germany; Northwest A&F University Yangling, China; Forestry Academy of Shaanxi, China; Thünen Institut, Germany; FEDRC GIZ Forest Policy Facility (Forestry Economics Development and Research Center of the Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH), Germany; and Center for Natural Forest Protection in Shaanxi, China) met to share their knowledge and deduce recommendations for future multifunctional forest management for the temperate zone. The workshop, held at the Northwest A&F University in September 2018, included presentations and intensive discussions, as well as a field tour. The results of the workshop that are summarized in this white paper are meant to provide an overview of the multi-faceted nature of the topic for interested scientists and forest practitioners, describe tools that can be used to analyze various aspects of multifunctionality and, in an exemplary fashion, highlight gathered experience from long- and short-term experiments. Included are social demands, economic goals, and scientific baselines. The topics reach from economic evaluations of forest ecosystem services over forest management practices, including afforestation, restoration, and preparations to face climate change, to wood/forest products utilization and participation of local people for poverty reduction. Overall, an optimistic picture emerges, showing that by using adapted forest management practices, which try to embrace the concept of multifunctionality, various use schemes and demands can be integrated at single sites, allowing us to achieve both environmental protection and productive forests, including societal demands, as well as aspects of tradition and national identity.

Forest and agricultural activities are the main income source in tropical regions. Ecuadorian farmers at the forest frontiers also depend on natural resources as part of their livelihood strategies; consequently, factors like deforestation and conservation strategies might limit the availability and accessibility to natural resources with potential implications for local economies. Rural income studies are still scarce for Latin America; moreover, there is a knowledge gap about how deforestation and conservation strategies affect rural income. This manuscript addresses this gap by analyzing whether the deforestation context and the presence of conservation strategies, command and control and incentive-based conservation, influence forest and agricultural income generated by rural farmers. Additionally, we explore the contribution of natural resources to rural income, providing insights on farmers’ dependency on natural assets. Our results are based on 1157 surveys applied to households in the lowland rainforest frontiers from the Central Amazon and the Northwestern Coast of Ecuador. We determined that more than 50% of household income comes from forest and agricultural activities. Regression results showed that in the Central Amazon, the deforestation context and conservation strategies did not have significant effects on forest income. However, indigenous households living close to an area under conservation derive higher income from agricultural activities. On the Northwestern Coast, where the forest is becoming scarce, high deforestation context is associated with higher forest and agricultural income at the household level. Nevertheless, indigenous people living around a conservation area derive more forest income and less agricultural income due to the intense timber extraction in privately owned forest remnants. This study provides useful information for policies aimed to improve rural economies and natural resources conservation.

Background and objectives: Smallholder households with a plot size of 1&ndash, 5 ha manage nearly half of Vietnam&rsquo, s acacia plantations. They mostly harvest acacia timber after short rotation periods (5&ndash, 6 years) producing woodchips with relatively low financial returns compared to potential profits from sawlog production through long rotation periods. The domestic wood production cannot yet meet the needs of the booming furniture industry for raw materials. This paper investigates factors that influence the adoption of long-rotation periods for sawlog production by small-scale plantation owners. Materials and methods: The impact of farmer and farm characteristics and the characteristics of the external environment on the probability to adopt long rotation periods is analyzed. The data were collected through focus group discussions (FGD) and a household survey to capture the wider socio-economic situation of small-scale plantation owners in central Vietnam. Findings: Results from FGDs and probit regressions show that factors that potentially constrain small-scale plantation owners from the production of sawlogs can be grouped into four themes: (1) small and fragmented land holdings, (2) high risks related to natural disasters and other biotic and abiotic hazards, (3) high production and monitoring costs, and (4) lack of knowledge and experience in plantation management. Conclusions: Potential policy approaches to promote the adoption of long rotation periods should include a package of measures that simultaneously address the constraints of smallholders and the various risks that they face.

In the context of implementing the Habitats Directive (92/43/EEC) approximately 17% of the German forest area was designated in “Special Areas of Conservation (SAC)”. Amongst these there are many beech forests which were not subject to a special protection status before. Management plans, containing measures for the protection of SACs, are just being developed. These measures may cause restrictions to forest management leading to losses of income. Our study aimed to analyse natural and economic impacts of the implementation of the Habitats Directive which could, e.g. be used as a basis for designing compensation schemes. In discussion with operational managers it became clear that the measures most restrictive to forest enterprises were small-area land set-aside, restrictions in choice of tree-species and maintenance of a sufficient share of mature stands. The impact of those nature protection measures on case-study forest enterprises was evaluated using an excel-based simulation model which enabled the calculation of, e.g., income losses based on enterprise individual data for a given simulation-period. The main factors influencing income losses were age-class distributions, management practices and objectives of forest enterprises. Annual income losses for the enterprises averaged 31 to 39 €/ha.

This paper assesses the effects that different economic instruments to reward carbon sequestration services might have on forest management, especially on the optimal rotation period. Three different carbon crediting schemes are considered, which are based on different accounting rules. The schemes are different with respect to the question whether and how to account for carbon emissions. The forest valuation method used for calculation is based on the land expectation value (LEV), which was adjusted for the value of carbon sequestration services. Changes in the LEV and optimal rotation are expected to be induced by the amount and interactions of carbon and timber prices, harvesting and regeneration costs, and interest rates. The optimal economic rotation period is calculated for single stands as well as for whole forest enterprises (fully regulated “normal” forests). Crediting the carbon sequestration of single stands—starting from the time of regeneration—is comparable to rewarding afforestation projects. When crediting forest enterprises with existing timber and carbon stocks, additional carbon sequestration compared to a reference is rewarded. The findings reveal that, depending on the carbon price level, the optimal rotation period is increased in all considered crediting schemes, but with different intensity. If wood removals have to be accounted as carbon emissions this has the most significant effect on the optimal rotation period for forest stands and enterprises. In this case the increase of the optimal rotation period by rising carbon prices is boosted additionally by rising interest rates. Different thinning regimes, however, have only little impact on the time of maximum LEV under carbon crediting schemes.

The objective of the presented study is to analyse the international competitiveness of the European forest industry sector and that of Switzerland in particular using constant market share (CMS) analysis. The analysis is conducted based on bilateral trade data in monetary terms for the years 2000 to 2005. Timber commodities are grouped into two sectors (the wood sector and the paper sector) as well as into three processing levels (raw wood, semi-finished and finished products). CMS analysis is conducted on two aggregation levels: the forest industry sector on the whole and the forest products sector as part of the semi-finished products sector. The analyses of both aggregation levels show similar results. Most of the traditionally industrialized countries show only low export growth rates. Countries with fast growing economies in general, in particular those from South East Asia and most of the Eastern European countries show high growth rates as well as high positive competitiveness effects. A positive relationship can be identified between a country's timber export growth rate and its competitiveness effect. Within Europe, Eastern European countries are gaining competitive advantage over Middle and Western European countries. CMS analysis indicates low international competitiveness for the Swiss forest industry sector, whereas Austrian and German forestry industry sectors are characterized by higher values of international competitiveness.

The paper presents a model to analyse trade in illegally harvested timber with a particular focus on trade via third party countries. The model is deduced from the conventional input–output-analysis. In contrast to this type of analysis, inverse export coefficients are introduced to analyse the effect of a certain amount of country-specific supply, e.g., of illegally harvested timber, to the use of wood and wood products of all other countries, based on trade relationships. A database has been compiled especially for application of the model. It comprises data on industrial round-wood production in terms of industrial wood harvested and removed from the forest; recovered wood fibre in the form of recovered paper and waste wood; bilateral trade of 272 wood-based commodities in m³ raw wood equivalent (rwe), and domestic use of those commodities. Two scenarios expressing high and low estimates of illegal harvesting for all countries have been employed in the model. The model reveals the trade linkages between all countries of the world and allows quantification of the global supply and use arising from illegal harvesting. Furthermore it allows calculation of the import of illegally harvested timber for each country of the world. And finally, the model likewise allows the quantification of domestic use of illegally harvested timber for each country of the world. The results show that international trade increases the global domestic supply of illegally harvested timber by more than 70% in each scenario. In particular industrial round-wood from Papua New Guinea, Malaysia, Indonesia and Myanmar passes through many countries until it ends in form of finished wood products in the country of final destination. Not only due to suggested illegally harvested timber in the own country, but also due to strongly developed trade relationships, China holds the lead in total supply and use of illegally harvested timber. However this result must be seen against the background of the large population in China. This aspect also helps to explain the predominant position of China, Brazil and Russia with regard to the domestic use of illegally harvested timber. A comparison of import of illegally harvested timber on the basis of “simple” (covering only bilateral trade) and inverse export coefficients demonstrates the model's merit. The hitherto usually simple approach underestimates the “real” trade by a third up to a half.

The objective of the presented study is to analyze the competitiveness of the German forest industry sector against the background of the international timber markets. The analysis is conducted based on global bilateral trade data in monetary terms. Timber commodities are grouped according to twelve commodity classes; each class is clearly attributed to one of the three processing levels raw wood, semi-finished and finished wood products. After an introductory description of the structure and development of the global timber market, two result-oriented competitiveness indicators have been applied: the revealed comparative advantage (RCA), which indicates whether a country is specialized in a specific sector—the RCA analysis has been conducted by means of the two consecutive indices Balassa index (BI) and Aquino index (AI)—and in addition the constant market share (CMS) analysis, which disaggregates the overall export growth of a country into four different effects: (1) the world growth effect, (2) the commodity-composition effect, (3) the market-distribution effect and (4) a residual, which usually is interpreted as the competitiveness effect. Depending on the chosen indicator, results are given for 21 and 25 leading countries (RCA and CMS, respectively). The highest BI values are shown by Russia for raw wood (10.4), by Finland for semi finished wood products (11.3) and by Poland for finished wood products (4.7). The AI shows that countries which are specialized in timber commodity exports mostly are significant timber importers, as well. This is an indication of their integration in an intra-industry trade. Germany only has a BI value somewhat greater than 1 for finished wood products. This can be seen as an indication of merely an average competitiveness position in global timber markets. The CMS analysis delivers two key results: most of the leading timber exporters in absolute terms show only low export growth rates and vice versa. Furthermore, a strong positive relationship can be identified between a country’s timber export growth rate and its competitiveness effect. Most of the Eastern European and many Asian and Latin American countries show this pattern, as they have high growth rates and high positive competitiveness effects. Germany’s export growth can be attributed much more to the overall world growth in timber markets than to its forest industry capacity. Hence, a stagnation of world growth would have crucial effects on the German forest industry sector.

Nach Beschlus des Europaischen Parlamentes sind fur die offizielle Berichterstattung zur Holz verarbeitenden Industrie neben dem Holz- und Papiergewerbe nun auch das Verlags- und Druckgewerbe zu zahlen. Statistisch hat der Bereich Forst- und Holzwirtschaft damit erheblich an Gewicht gewonnen. In ihm waren nach dieser neuen Sektorenabgrenzung in der Bundesrepublik Deutschland im Jahr 1997 knapp eine Million Menschen in etwa 90.000 Betrieben erwerbstatig. Sie erwirtschafteten einen Produktionswert in Hohe von etwa 100 Mrd. EUR. Der Anteil der Forst- und Holzwirtschaft an der Gesamtwirtschaft hat sich damit, gemessen sowohl an der Zahl der Erwerbstatigen als auch am Produktionswert, in etwa verdoppelt. Gleichwohl betragt er nur ca. 3%. Die vergleichende Auswertung unterschiedlicher amtlicher Quellen zeigt, das es im Ergebnis zu keinem grosen Unterschied fuhrt, ob die vergleichsweise grobe Systematik nach der Volkswirtschaftlichen Gesamtrechnung oder eine starker differenzierte Systematik nach verschiedenen Bereichsstatistiken gewahlt wird. Anhand der Input-Output-Tabellen – die zur Zeit aktuellsten liegen fur das Jahr 1997 vor – lassen sich die internen und externen Verflechtungen der Produktionsbereiche der Forst- und Holzwirtschaft analysieren. Es zeigt sich, das die Vorleistungen sowohl auf der Aufkommens- als auch auf der Verwendungsseite eine grose Bedeutung besitzen. Im Durchschnitt finden mehr als 60% der Produktion der Forst- und Holzwirtschaft als Vorleistungsguter in anderen inlandischen Produktionsbereichen Verwendung. Allerdings sind die Vorleistungen der Forst- und Holzwirtschaft in keinem anderen Sektor von hoher Bedeutung. Hohe Input-Koeffizienten innerhalb der Forst- und Holzwirtschaft besitzen die Zellstoff- und Papierindustrie fur die Papierverarbeitung sowie das Druckgewerbe fur das Verlagswesen. Die jeweils hohen Import- und Exportkoeffizienten der Zellstoff- und Papierindustrie deuten auf eine stark ausgepragte internationale Arbeitsteilung innerhalb des Papiersektors hin. Die relativ niedrigen inversen Koeffizienten lassen nur geringe Impulse einer allgemeinen Endnachfragesteigerung auf den Produktionsbereich Forst- und Holzwirtschaft erwarten.

Basierend auf Inventurergebnissen (Daten der Bundeswaldinventur sowie verschiedener Datenspeicher, insbesondere des Datenspeichers Waldfonds) und gestutzt auf Ertragstafelangaben fur die Zuwachsschatzung sowie auf eine Literaturauswertung zu empirischen Mesergebnissen von Biomassekomponenten im Wald wurden der Kohlenstoffvorrat der Baume und dessen jahrliche Veranderung in den Waldern Deutschlands berechnet. Baumartenspezifische Regressionsschatzungen wurden zur separaten Berucksichtigung von Asten und Zweigen, Nadeln sowie Wurzeln entwickelt und angewendet. Als Wachstumsmodelle wurden Ertragstafeln herangezogen. Der Kohlenstoffvorrat im Wald in Deutschland betragt 2.249 Mio. t C, davon sind mit 1.081 Mio. t C etwa die Halfte in Baumen gebunden. Der ober- und unterirdische jahrliche Nettozuwachs der Baume liegt bei ca. 15 Mio. t C. Der Kohlenstoffvorrat je Hektar in Deutschland erreicht je nach Altersklasse und Baumart bis zu 120–190 t C/ha.

The aim of this paper is to estimate the future carbon balance of wood use in Germany combining a national forest inventory data‐driven forest growth model with information about German harvested wood products markets and taking into account material and energy substitution effects. In a scenario analysis, we assess impacts of different forest management options, change of market share of harvested wood products as well as changes of the national energy mix. Additionally, the model settings and assumptions that predominantly determine the results are identified and discussed. The simulation results show that only a radical change of forest management in Germany would cause net carbon emissions. The continuation of current forest management or a higher share of high yield tree species as well as a change of market shares of wood and wood products would result in a net carbon sequestration in German forest and harvested wood products carbon pools. Considering substitution effects, even the net carbon emissions of a radically changed forest management would be over compensated and the carbon balance of all other scenarios would become even more positive. Looking at the most decisive factors regarding our simulation results, the initial treatment of the forest carbon pool, the starting year for the simulations and the present forest structure are most crucial for further accumulated net carbon pool changes. WIREs Energy Environ 2018, 7:e260. doi: 10.1002/wene.260 This article is categorized under: Bioenergy > Climate and Environment Energy and Climate > Climate and Environment Energy and Development > Climate and Environment

This study presents a model for including natural risks (such as storm or insects) in the calculation of land expectation values. Applying this model, an answer has been found to the question as to whether consideration of risk would lead to changing recommendations regarding the choice of species and the length of rotation periods from the point of view of profitability. The study is based on well-founded, empirical growth data and survival probabilities for a specific region in southern Germany. It shows that spruce is the more profitable species, even if its survival probability is noticeably lower than that of beech, especially when the trees are older. When survival probabilities are considered, the economic superiority of spruce is not affected, but their optimum rotation period is reduced from 90 to 80 years.

Der Beitrag stellt eine betriebswirtschaftliche Untersuchung zum Umbau von Fichtenreinbestanden in Laub- und Laubmischbestande vor. Untersuchungsgegenstand ist ein ca. 80 Jahre alter Fichtenreinbestand, der im Laufe der nachsten 40 Jahre zur Endnutzung ansteht und in einen Laub- bzw. Laubmischbestand umgebaut werden soll. Auf den Untersuchungsbestand werden unter Zuhilfenahme eines Wuchsmodells sechs verschiedene Waldbehandlungskonzepte angewandt, die sich hinsichtlich des Beginns des Waldumbaus, des Umbauzeitraumes sowie der Umbauintensitat unterscheiden. Es wird jeweils eine Variante mit Umbau durch Voranbau und eine mit Waldumbau nach der Endnutzung berechnet. In die okonomische Bewertung der Varianten gehen die erntekostenfreien Erlose aus den Holznutzungen sowie die Kulturausgaben ein. Uberlebenswahrscheinlichkeiten, die das unterschiedlich hohe Sturmschadenrisiko der verschiedenen Waldbehandlungskonzepte zum Ausdruck bringen, finden besondere Berucksichtigung in den Kalkulationen. Beurteilungskriterium der Varianten ist der Erwartungswert des Kapitalwertes, der fur vier verschiedene Zinsforderungen, 0, 1, 1,5 und 2 % berechnet wird. Sensitivitatsuntersuchungen fur veranderte Uberlebenswahrscheinlichkeiten sowie Berechnungen zum Einflus niedrigerer Kulturausgaben werden durchgefuhrt. Zuletzt werden die Auswirkungen sich verandernder Holzpreise und Erntekosten auf die Erwartungswerte der Kapitalwerte aufgezeigt. Es last sich zeigen, das sich die Voranbauvarianten trotz der mit der Auflichtung verbundenen Zuwachsreduktion und der Erhohung des Sturmschadenrisikos als in der Regel vorteilhafter erweisen. Dies begrunder sich vor allem mit den niedrigeren Kulturausgaben fur Voranbauten sowie damit, das die ersten Einnahmen, die im Zuge der Auflichtung des Bestandes entstehen, wegen des kurzen Diskontierungszeitraumes in ihrer Hohe nur wenig gemindert in den Erwartungswert des Kapitalwertes eingehen. Deutlich niedrigere Kulturausgaben fur alle betrachteten Konzepte konnen die Vorteilhaftigkeitsreihung zugunsten der Varianten ohne Auflichtung umdrehen.

Background Forests occur across diverse biomes, each of which shows a specific composition of plant communities associated with the particular climate regimes. Predicted future climate change will have impacts on the vulnerability and productivity of forests; in some regions higher temperatures will extend the growing season and thus improve forest productivity, while changed annual precipitation patterns may show disadvantageous effects in areas, where water availability is restricted. While adaptation of forests to predicted future climate scenarios has been intensively studied, less attention was paid to mitigation strategies such as the introduction of tree species well adapted to changing environmental conditions. Results We simulated the development of managed forest ecosystems in Germany for the time period between 2000 and 2100 under different forest management regimes and climate change scenarios. The management regimes reflect different rotation periods, harvesting intensities and species selection for reforestations. The climate change scenarios were taken from the IPCC's Special Report on Emission Scenarios (SRES). We used the scenarios A1B (rapid and successful economic development) and B1 (high level of environmental and social consciousness combined with a globally coherent approach to a more sustainable development). Our results indicate that the effects of different climate change scenarios on the future productivity and species composition of German forests are minor compared to the effects of forest management. Conclusions The inherent natural adaptive capacity of forest ecosystems to changing environmental conditions is limited by the long life time of trees. Planting of adapted species and forest management will reduce the impact of predicted future climate change on forests.

Die Anspruche, die die Gesellschaft an den Wald stellt, sind vielfaltig. Dabei haben sich im Zeitablauf auch deutliche Akzentverschiebungen in der Gewichtung der einzelnen Anspruche ergeben. Diese kann man grob nach den Funktionen untergliedern, die der Wald im Interesse der Allgemeinheit erfullen kann.

Die Globalisierung der Rohstoff- und Warenmarkte stellt die deutsche Forst- und Holzwirtschaft vor neue Herausforderungen. Sie hat zu einer steigenden Holz-nachfrage und zum Aufbau neuer Produktionskapazitaten der Holzindustrie gefuhrt. Ziel der Clusterstudie Forst und Holz Niedersachsen ist es, die Wettbewerbsfahigkeit der niedersachsischen Forst- und Holzwirtschaft vor diesem Hintergrund zu starken. Hierzu wurden die inneren Strukturen (Betriebe, Umsatze, Beschaftigungszahlen) und wirtschaftlichen Potenziale analysiert, die moglichen Holzaufkommen bei Unterstellung verschiedener Bewirtschaftungsstrategien fur einen Zeitraum von 30 Jahren prognostiziert und die wesentlichen Einflussfaktoren auf das zu erwartende Nutzungsverhalten der Forstbetriebe aufgezeigt. Niedersachsen hat bundesweit die drittgroste Waldflache. Der hohe Kleinprivatwaldanteil und ungunstige Altersstrukturen erschweren eine stetige Holznutzung. Mit einem Umsatz von ca. 15 Mrd. € im Jahre 2005 betrug der Beitrag des niedersachsischen Forst und Holz Clusters zum steuerlich ausgewiesenen Gesamtumsatz des Landes 3,4 %. Mit diesem Umsatz steht der niedersachsische Cluster im bundesweiten Vergleich immer noch an 4. Stelle, obwohl in zahlreichen anderen Bundeslandern neue Produktionskapazitaten der Sage- und Holzwerkstoffindustrie aufgebaut wurden. Die Ergebnisse der Holzaufkommensprognosen auf der Basis der drei Waldentwicklungsszenarien „naturnaher“, „ertrags-“ und „naturschutzorientierter“ Waldbau weisen darauf hin, dass in bereits heute intensiv nutzenden Forstbetrieben mit einem guten Pflegezustand sich durch eine Modifikation der Waldbaustrategien kaum noch zusatzliche Rohholzmengen mobilisieren lassen, ohne die Nachhaltigkeit zu gefahrden. Den wichtigsten Ansatzpunkt zur Steigerung des Rohholzaufkommens stellen die bisher nicht bewirtschafteten Waldflachen dar. Auf der Basis der Clusterstudie Forst und Holz Niedersachsen lassen sich nun gemeinsame Strategien der Forst- und Holzwirtschaft entwickeln. (Literatur-Standort: 1147)

A forest enterprise manager runs risks, when deciding about harvesting strategies. The postponement of the harvest of a stand may yield, with a specifreprohability, a higher profit. However, as a consequence of storm damage, financial losses may occur. The risk of storm damage varies between different stands, similar to the price risk between shares. In this study, the problem of stand selection for final cuts is compared with the problem of optimising a portfolio. Investors that consider only the expected net present value in their investment selection are regarded as risk neutral. Empirical studies show that investors who also consider the range of the profit dispersion are usually risk averse. As a subjective decision criterion from the field of portfolio selection, the tern “expected utility” is used. The expected utility results from reduction of the expected value subject to the level of risk (variance) and the risk aversion of the decision maker. When the decision involves more investments, the risk correlation between the different investments is also taken into account. By means of examples, the use of this decision criterion in forest management is shown. One example concerns the selection of harvesting strategies. Considering a number of equally mature stands, a forest manager has to decide which stands to cut either today, or 20 or 40 years later. Waiting yields a higher profit, if no storm damage occurs. In case of a damage, the income is less than the present.stumpage value. In the second example, different probabilities of storm damage are allowed for the stands. The optimal harvesting strategy can be selected using a non-linear optimisation method. Although currently suitable decision support models from the field of Operation Research exist, formal and conscious risk management has not been implemented in German forestry. Finally, the obstacles for the implementation of improved planning tools in forest management are discussed and the future prospects of their application are assessed.