Introduction
In the last two decades increasing attention has been paid to the links between biodiversity, forest ecosystem resilience, and climate change. However, while some authors claim that the resilience inher- ent to intact forest ecosystems – fully functional units of plants, animals, micro-organisms, and fungi – provides the best insurance against climate change and improves the prospects for ensuring that forests meet the needs of present and future generations (e.g. Thompson et al. 2009; Ibisch and Blumröder 2020), others doubt that forest ecosys- tems can cope with rapid climate change and advo- cate more active adaptation strategies (e.g. Messier et al. 2019).
The Ninth Conference of the Parties to the Con- vention on Biological Diversity (CBD) hosted by Ger- many in 2008 had put the biodiversity of forests at centre stage. In the run-up to the conference, Ger- many adopted a comprehensive and ambitious National Strategy of Biological Diversity (NBS) aim- ing at the implementation of the CBD’s targets on the national level (BMU 2007). The NBS considers the European framework (e.g. Birds Directive, Hab- itats Directive, Natura 2000) as well as relevant obligations to international agreements and con- ventions. The NBS addresses not only public admin- istrations on the federal, state, and community lev- els, but all relevant societal stakeholders.
The adaptation of forests to climate change is one of several specific targets of the NBS, but it is
the one that is currently the subject of most contro- versy. The extreme summer droughts and heat- waves of 2018, 2019, and 2020, combined with storm events and large-scale bark beetle outbreaks, have led to severe damage in German forests and represent a historical challenge to German forestry.
Currently, the area affected by forest dieback is estimated to amount to 285 000 ha, but this area might significantly increase in the coming years.
Most damage occurs in coniferous forests (fig. B 10.1), but broadleaved trees are affected too, although to a minor degree.
Man-made climate change is considered to be the main cause for the recent increase of distur- bances in forests. Thus, if the adaptation of forests to climate change is to succeed, greenhouse gas emissions must be reduced worldwide and other external stressors further amplifying the effects of climate change (e.g. atmospheric nitrogen inputs, groundwater lowering, and spread of alien inva- sive species or habitat fragmentation) must be effectively contained.
However, the current situation may also be seen as an opportunity to revisit current silvicul- tural management concepts, control instruments, and planning approaches so that they can more effectively meet the challenges of climate change.
Sustainable management strategies must better take into account the dynamics and unpredictabil- ity of climate change and the complex responses of ecological systems to such changes.
According to Milad et al. (2012) the objective of forest management should be to develop diverse, resilient forests that can adapt or reorganise them- selves in the face of climate change while maintain- ing their basic functions and ecological services (see also Puettmann et al. 2008; Filotas et al. 2014). This
Forests under a changing climate: increasing adaptability and resilience through
more diversity and heterogeneity
A. Höltermann
< Fig. B 10.1. Medium-aged homogeneous spruce stand.
Bigger parts of the forest were dying and removed because of drought and subsequent bark beetle infesta- tion in Rhineland-Palatinate (Photo: Anke Höltermann).
B 10
Federal Agency for Nature Conservation, Bonn, Germany
implies that existing silvicultural management con- cepts and approaches which assume the predictabil- ity of ecosystem processes, and favour homogene- ous planning, management units, and economic objectives should undergo a fundamental reorien- tation. That is to say, there is a need to move away from the traditional, anticipatory management par- adigm in forestry towards a more process-oriented, incremental, and adaptative nature paradigm.
Management decisions following this approach should be guided by the following principles:
They should be as robust and flexible as possi- ble, i.e. independent from a specific climate sce- nario as well as open and responsive to new infor- mation and stochastic events (Millar et al. 2007;
Ogden and Innes 2009). According to the concept of adaptive management, goals and measures have to be evaluated repeatedly on the basis of model- or scenario-based planning processes and, if neces- sary, adjusted (Bolte et al. 2009; Filotas et al. 2014;
Lawler et al. 2010; Wintle and Lindenmayer 2008).
A comprehensive forest ecosystem monitoring that goes beyond the existing production-oriented monitoring programmes and puts more emphasis on the functionality of the forest ecosystem, includ- ing its biodiversity, is critical for this purpose. It should provide feedback to forest practitioners on a regular basis.
Furthermore, management strategies should focus more on promoting diversity and heteroge- neity at various levels. The improvement and con- servation of biodiversity – including genetic, spe- cies, and habitat diversity – forms the basis to maintain the self-regulating capacity of forest eco- systems and for providing diverse ecosystem ser- vices (Chapin III et al. 2000; Folke et al. 2004;
Hooper et al. 2005; Naeem et al. 2016; IPBES 2019).
This overall objective should be supported by a variety of management approaches, as these pro- vide opportunities for facilitating learning and adaptation processes that strengthen the resilience of the ‘human-environment system’ in the long term (Milad et al. 2012; Puettmann et al. 2008). In this sense, different ownership structures and diverse management forms, ranging from more production-oriented forests to no-action, and from experimental forms of forestry in private forest enterprises to the stronger integration of citizens‘
interests in public forests, provide the basis for a wide range of silvicultural systems, conservation approaches, and forest types.
Based on these principles, in autumn 2019, the Federal Agency for Nature Conservation (German:
Bundesamt für Naturschutz, BfN) published a posi- tion paper on ‘Forests and Climate Change’ (Ger- man: Wälder im Klimawandel) (BfN 2019). The posi- tion paper presented recommendations for a forest management focussing on the adaptation of for- ests to changing environments and social needs and provides proposals for their implementation.
The position paper addressed four issues: (I) How to reforest disturbed forest areas? (II) Which trees to choose? (III) Forest conversion; and (IV) Forest man- agement accounting for the functionality and integrity of forests. The key aspects of the paper are summarised in this chapter.
Enhancing the adaptability and resilience of forests through increased diversity and heterogeneity – key actions
I. Increased use of natural reforestation as adaptation mechanisms
Large areas affected by forest dieback have to be reforested in the coming years. As emergency relief to private forest owners, the German Federal Gov- ernment and the states of Germany announced to provide a large-scale funding programme of € 800 million in total (BMEL 12. 12. 2019) for clear-up and reforestation of the damaged areas. The objective is to reforest the areas as fast as possible.Environ- mental organisations and scientists have criticised this approach as it is likely to recreate extensive, homogeneous forest stands that are vulnerable to the impacts of future climate change (open letter to the Federal Minister of Food and Agriculture Julia Klöckner of 10 August 2019).
BfN also postulates that not all dead trees should be removed from affected forest stands, unless this is unavoidable owing to concerns about pest management and public safety. Clearing and driving heavy equipment across large areas can cause serious damage to soil structures (Hildebrand et al. 2000; Schäffer 2002) and limit the chances of successful reforestation (WBW 2018). In contrast, remaining deadwood in its various forms will ensure diverse structures as well as gradients of light, tem- perature, and moisture, and thus increase habitat diversity in the following stand (Beudert et al. 2015;
Kulakowski et al. 2017). In general, natural succes- sion enables the establishment of better adapted
trees and supports a higher genetic diversity com- pared to artificial regeneration (Lässig 2000; Cavers and Cottrell 2015; Roloff and Grundmann 2008). It should be preferred whenever possible (fig. B 10.2).
However, in situations when the existing tree species or provenances are no longer adapted – e.g.
when Norway spruce (Picea abies) is regenerating in former Norway spruce stands, artificial regenera- tion might be the only viable alternative to regen- erate the forest. Even then, natural forest develop- ment should be permitted at least on parts of the area to monitor the self-organised adaptation pro- cesses of the ecosystem.
II. Choice of tree species
The overall aim of reforestation should be to estab- lish diverse, resilient forests that are as close as pos- sible to the structure and functionality of our native forest ecosystems, as this is expected to provide the best insurance against climate change. Deciduous broadleaved forest is the prevailing natural poten- tial vegetation in most of Germany. Therefore, coniferous species such as Scots pine (Pinus sylves- tris) and Norway spruce (Picea abies) should no longer be cultivated in monoculture on large areas, but mixed in groups with indigenous broadleaved
tree species. This also reduces the risk of forest fires (FNR 2019) and improves nutrient flows (Emmer et al. 1998). Exceptions are those few sites on which conifers grow in pure stands even under natural conditions (e.g. Picea abies/Abies alba/Larix decidua stands on high-montane to sub-alpine sites or Pinus sylvestris stands on subcontinental sites of sand/sili- cate rock).
Light-demanding species such as oak (Quercus robur, Q. petraea, Q. pubescens etc.) and accompa- nying tree species like wild service tree (Sorbus torminalis), service tree (Sorbus domestica), field maple (Acer campestre) or Montpellier maple (Acer monspessulanum) could be promoted on tempo- rarily open, unstocked areas following distur- bances.
Non-native tree species, i.e. species that have been introduced into an area outside their natural range as a result of direct or indirect human involve- ment, should only be cultivated in a very restricted manner. Uncontrolled introduction in the sense of
‘experimenting with new forest types’ may increase the number of usable species in the short term. In the long term, however, this can lead to a decline in biodiversity because of the disruption of estab- lished species and habitat relationships (Roloff and Fig. B 10.2. Protected by lying and standing deadwood, a diverse new tree generation establishes after bark beetle infestation in the Harz National Park (Photo: Harz National Park).
Grundmann 2008). Their cultivation may even trig- ger irreversible processes that eventually lead to a restriction of ecosystem services and future man- agement options. The severe impairments to for- estry and nature conservation resulting from the introduction of the late-flowering black cherry (Prunus serotina) to Germany (fig. B 10.3), and the fact that a further eight alien tree species (Acer negundo, Ailanthus altissima, Fraxinus pennsylvan- ica, Pinus strobus, Populus canadensis, Pseudotsuga menziesii, Quercus rubra, Robinia pseudoacacia) were found to be invasive in Germany (Nehring et al. 2013; Vor et al. 2016) should serve as a warn- ing.
For these reasons and in accordance with the precautionary principle, indigenous tree species
(and preferably regional provenances) should always be given priority over non-native tree spe- cies unless there is scientific evidence that indige- nous tree species can no longer maintain important ecological services. BfN is not principally opposed to the use of non-native trees but demands that these are only cultivated, if: (1) their cultivation is based on a thorough ecological risk assessment and long-term ecological monitoring; (2) measures for prevention, early detection, and response are in place to minimise negative effects of alien tree spe- cies becoming invasive (e.g. control and surveil- lance of stands, regulations for cultivation, prohibi- tion of use in certain areas, removal, etc.); and (3) the nature conservation goals at the specific site are not affected.
Fig. B 10.3. Late-flowering black cherry (Prunus serotina) invades pine forests on the lower terraces of the Rhine near Schwetzingen and prevents the regeneration of native tree species (Photo: ILN Brühl).
The introduction of non-native tree species into protected areas, especially nature conserva- tion areas, Special Areas of Conservation (SACs) and Special Protection Areas (SPAs), should in gen- eral be avoided.
III. Accelerate ecological forest conversion
Structurally rich, mixed forests, displaying a broad ecological amplitude have a higher resilience and adaptability to climate change induced distur- bances when compared to single tree species stands (Jenssen et al. 2007; Pretzsch et al. 2013; Schelhaas et al. 2003). This is nothing new. In the last three decades, public forests and some privately owned forests have increasingly focused their activities on the principles of close-to-nature forest manage- ment. However, still more than half of the forest cover in Germany continues to be dominated by non-site-adapted coniferous forests (BWI 2012), of which about 3 million ha are pure stands. There- fore, efforts for ecological forest conversion need to be intensified. Each year until 2017, approxi- mately 22 000 ha of forest were converted to more natural stands (UBA 2019). At this rate, the conver- sion of all pure coniferous stands would take at least another 100 years.
Preference should be given to site-specific regeneration methods over long periods of time as these will contribute to the preservation of genetic diversity and allow better adaptation to climate change through natural selection processes (Bonfils and Bollinger 2003; Kätzel 2009; Milad et al. 2012).
Indigenous tree species should always be priori- tised (see Choice of species section). Nevertheless, as in the case of reforestation, when site conditions are expected to change rapidly and non-site- adapted, high-risk tree species spontaneously regenerate, then active removal and planting of more suitable species (including non-native species, particularly from European regions and which have undergone a certain coevolution) might be the only solution (Milad et al. 2012; Bolte and Ibisch 2007).
However, on many sites the lack of natural regeneration is not a matter of unsuitable site con- ditions or the absence of seed trees, but rather a question of high densities of browsing ungulates.
To succeed with forest conversion, a balance between forest regeneration and ungulate density is absolutely crucial. The BfN, therefore, welcomes all measures aimed at defusing the conflict between
silviculture and game management. Action could include adapting hunting regimes/seasons or estab- lishing ungulate control fences to enable monitor- ing of ground vegetation and establishment of tree seedlings.
IV. Align forest management with ecosystem considerations
Beyond reactions to acute disturbance events and forest conversion, forest management should always strive to enhance the integrity and function- ality of the forest to reduce its vulnerability to the effects of changing environments. Five measures seem to be particularly important: (1) Improve water balance and water retention; (2) Use appro- priate machinery and protect forest soils; (3) Allow forests and trees to age; (4) Increase the amount of deadwood; and (5) Increase the area of unman- aged forests. Each of these is discussed in the rest of this section.
Improve water balance and water retention Stand thinning, timber harvesting, or the establish- ment of forest/skidding roads should always be conducted in a manner that helps to preserve or improve the forest microclimate and soil water sup- ply. This will buffer temperature extremes and reduce water competition (Bolte and Ibisch 2007;
Ellison et al. 2017; Vose et al. 2016). Broadleaved forests generally have more seepage and ground- water recharge as compared to coniferous forests (Ellison et al. 2017; Lasch et al. 2012). Other factors and measures which improve the water retention potential of forests include: the amount of dead- wood in a forest as this can retain significant quan- tities of water especially in old forest; the use of soil-conserving forestry technology; the closure of drainages; the discharge of water from forest roads/paths back into the stand; and the reactiva- tion of forest moors. Also, to effectively improve the hydrological regime of a forest, it may be essen- tial to include the surrounding landscape into the water management regime (fig. B 10.4).
Use appropriate machinery and protect forest soils For timber harvesting and other silvicultural inter- ventions there is often no alternative to the use of heavy machinery, although, this may often contrib- ute to the homogenisation of forests (Puettmann et al. 2008). Today, a variety of technical processes are available to meet the increasingly demanding requirements related to wood harvesting and
transport. These have become economically effi- cient in terms of the value chain and take into account aspects of occupational health, safety, and ergonomics. Despite these advances, such tech- niques must be applied consistently as well as being subject to a constant process of further improve- ment and adaptation to the changing climatic con- ditions (e.g. fewer frost days, more late frost, and more frequent disturbance events) to minimise the negative effects on the forest ecosystem.
The conservation of soils (especially hydromor- phic soils and upland/lowland moors) is of particu- lar importance and should be a priority in the development of harvesting methods. Skidding should be always limited to permanently marked trails to avoid unnecessary soil compaction. Driving outside those trails should be prohibited, as it can lead to considerable compaction of soil layers close to the surface, even after one single harvesting event. Eventually this can lead to far-reaching neg- ative or partly irreversible effects on soil properties and destabilise whole forest stands (Hildebrand
et al. 2000; Schäffer 2002). Soils that are still largely intact should remain as undisturbed as possible in the long term.
Allow forests and trees to age
Currently, it is impossible to definitively assess whether German forests still serve as carbon sinks or if more carbon is emitted (at least at local/
regional level) than absorbed (Hüttl 2019). Thus, rotation lengths in forest types, which have shown a lower risk to disturbances, should be extended to compensate for any possible loss of biomass, increase the long-term carbon stock and improve the adaptability of forests.
According to the Third Federal Forest Inventory (BWI 2012), the proportion of old forests (>160 years) was estimated to be only 3.2 % of the total forest area, despite slight increases (Reise et al. 2017). Numerous studies agree that large areas of old forests with habitat continuity can bet- ter buffer climate extremes than younger forests.
Besides their important functions of carbon storage
Fig. B 10.4. In the ‘Bienwald’ forest conservationists, farmers, and the state forestry agency work together to restore a near-natural water regime in the forest and the surrounding landscape. The large-scale nature conservation project is funded by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (German:
Bundesministerium für Umwelt, Naturschutz und nukleare Sicherheit, BMU) (Photo: Manfred Wüst).
and sequestration (Körner 2017; Luyssaert et al.
2008; Mund et al. 2015; Schrumpf et al. 2014) the older forests are also more resistant to heat and drought owing to their high functional complexity and structural diversity (Ellison et al. 2017; Norris et al. 2012; Noss 2001; von Oheimb et al. 2014;
Thom et al. 2019). Older forests generally have more biomass and more extensive root networks, which enable them to store larger amounts of water and to better access available water resources. Older forests and forests in the decay stage also have positive effects on the diversity of habitats and harbour well-adapted animal, plant, and fungal species, depending on the specific habi- tat structures. Nevertheless, current observations of extensive loss of old beech (Fagus sylvatica), e.g. in the Hainich National Park (fig. B 10.5), indicate that even these types of forest are not fully immune to the effects of climate change. Further research is required to better understand the underlying causes and to reassess existing knowledge in the light of these observations.
Increase the amount of deadwood
The current dieback can be an opportunity to sig- nificantly increase the amount of deadwood in for- ests. Deadwood contributes considerably to biolog- ical diversity and heterogeneity of our forests and hence positively affects forest resilience: i.e. it con- tributes to the regulation of the microclimate in forests because of its water storage capacity, and its positive effects on humus formation, energy and nutrient cycles, and the regeneration of woody plants (Norris et al. 2012).
The Third Federal Forest Inventory estimated the amount of deadwood in German forests to be 20.6 m3/ha on average in 2012. Deadwood from coniferous species made up two thirds of the total amount of deadwood, and root plates made up more than one quarter (BWI 2012). In comparison, in primary beech (Fagus sylvatica) forests of Uholka- Shyrokyi Luh in the Ukraine, the average dead- wood amount was 180 m3/ha (Mund et al. 2015). A considerable accumulation of deadwood is also found in forests that have not been managed for at Fig. B 10.5. Area with dying spruce and beech forests on south-west slopes in the western part of the Hainich National Park (Photo: FSU Jena).
least 50 years (Bütler and Schlaepfer 2004) (fig.
B 10.6). In contrast, the average amount of dead- wood in Germany is insufficient and especially cer- tain deadwood types, for instance deadwood from large standing broadleaved species, is largely miss- ing (Reise et al. 2017). The current dieback can be a chance to address this deficiency.
Increase the area of unmanaged forests
The national biodiversity strategy (NBS) of the Ger- man Federal Government of 2007 set the goal to set aside 5 % of the forest area by 2020 for natural development (BMU 2007). To serve as a role model, the target for public forests is higher, at 10 % of the forest area. However, results from a research project funded by the BfN, shows that the forest area with natural forest development only
amounted to 2.8 % of the total forest area in 2019 (Engel 2019). Thus, it is clear that the target of the NBS will not be achieved. As a consequence, efforts to increase the proportion of forest area with natu- ral development should be considerably enhanced and the recognition of their importance for climate protection and adaptation improved.
Unmanaged forests support natural adapta- tion processes in response to climate change (Cav- ers and Cottrell 2015; Kulakowski et al. 2017; Milad et al. 2012; Puettmann et al. 2008; Thom et al.
2017) and are necessary to maintain the full range of biodiversity typical for forests. Continued devel- opment without human intervention enhances both the biodiversity and the ecological integrity of the ecosystem (Müller and Burkhard 2012; Norris et al. 2012). Appropriate large areas of largely
Fig. B 10.6. Deadwood of different dimensions and stages of decay in the forest nature reserve Eichhall, Spessart, Bavaria (Photo: Anke Höltermann).
anthropogenically undisturbed forests and the per- meability of the forest landscape for animals and plants enable the development of adapted ecosys- tems in the long term. Areas, in which natural development processes are continuously given pri- ority, are also crucial for scientific research on the impacts of climate change on ecosystems and, therefore, must be included in long-term monitor- ing programmes.
In the current situation BfN is concerned about the increasing pressure on the administrations of National Parks and Biosphere Reserves to allow the removal of dead trees. It is critical that any kind of human intervention must be avoided in the core zones of these conservation areas. Large- scale disturbances such as storms, insect infesta- tions, and forest fires can support restoration of forest ecosystems by recreating some of the struc- tural complexity and landscape heterogeneity pre- viously lost through intense management (Beud- ert et al. 2015; Lindenmayer et al. 2004; Müller et al. 2019). Therefore, fellings and clearing-up after disturbances must strictly be limited to buffer zones and only be permitted if sound scientific information indicates a high risk for neighbouring forests.
Suggestions for the implementation
The implementation of the proposed management recommendations is a huge challenge that should be supported by political strategies, federal and state programmes, and appropriate legislation. To this end, BfN calls for changes mainly in the follow- ing three areas: (1) Strengthen forest management to support public welfare; (2) Assuming responsibil- ity by the federal government and making legal adjustments; and (3) Extend monitoring of forest ecosystems and intensify applied research.
Strengthen forest management to support public welfare
Approximately half of the German forest area is owned by private forest owners. The federal and state governments provide for forestry promo- tional programmes as part of the Joint Task for the Improvement of Agricultural Structures and Coastal Protection (German: Gemeinschaftsaufgabe Agrar- struktur und Küstenschutz, GAK) that are targeted at communal and private forest owners.
The public payments allocated through these programmes should be more consistently linked to public welfare. For example, forest owners, who continue to rely on pure coniferous forests, should no longer qualify to receive public support follow- ing calamitous events. The same should apply to silvicultural practices, which foster homogeneous forest stands and, thus, have a higher risk of being affected by disturbances.
The current revision of the framework of the EU Common Agricultural Policy (CAP) as well as the GAK provides the opportunity to tighten the requirements for public payments to private forest owners. These payments should be more consist- ently linked with measures to improve the func- tionality and integrity of the forest ecosystems. Eli- gible measures may include: promoting the use of site-adapted, indigenous tree species; retaining deadwood; creating diverse forest edges; and pro- moting natural reforestation processes over time spans up to 30 years (with or without prior clearing of the forest site). To ensure uptake by forest own- ers such measures must be economically attractive as well as, in the first instance, offered by the respective state government (Franz et al. 2018).
Assuming responsibility by the federal government and making legal adjustments BfN advocates for adjustments in national legisla- tion related to forests, nature conservation, and hunting in line with the above-mentioned objec- tives, for example by:
– Emphasising the key role of forests for nature and environment in contrast to a biased focus on the economic benefits of timber production in the Federal Forest Act (German: Bundeswaldge- setz, BWaldG).
– Introducing ambitious objectives for climate and biodiversity policies in state forests, which are mainly owned by the federal government and the federal states. State forests occupy a third of the German forest area.
– Defining the requirements of good practice in forestry in detail. The requirements under nature conservation law can and must be specified and supplemented by further statutory or sub-statu- tory requirements in a legally binding manner.
– Anchoring the principle ‘forest before game’
through a commitment to adapted game popu- lations in the Federal Hunting Act.
Extend monitoring of forest ecosystems and intensify applied research
Existing forest monitoring programmes should be reviewed to analyse their suitability for assessing the effectiveness of adaptation measures and whether or not they allow conclusions on the suita- bility of tree species and forest ecosystems under a changing climate. Comprehensive data is already collected in forests through environmental forest monitoring and other forest-related programmes (e.g. the Federal Forest Inventory, forest monitor- ing on national natural heritage sites, SAC forest monitoring). In the future these programmes need to be expanded in order to:
– Adequately document changes in forests ecosys- tems caused by climate change at national, regional, and local levels.
– Assess the effects of adaptation measures regard- ing the preservation of ecosystem functions and biodiversity in the long term.
– Forecast the long-term suitability of forest trees and forest ecosystems under climate change con- ditions.
Embedding permanent forest monitoring into applied research programmes will promote the knowledge transfer into silvicultural practices and strengthen communication between science and forestry practice. The exchange is crucial to enable a continuous adaptation of silvicultural interven- tions. Moreover, monitoring should be comple- mented by long-term, extensive forest ecosystem research addressing fundamental questions of for- est ecosystem adaptability and resilience in the face of changing environmental conditions and societal needs.
Conclusion
Preserving and developing resilient forests and for- est landscapes under the conditions of climate change is a huge challenge. Only by cooperating and bundling all relevant knowledge and compe- tences can conservationists and foresters find ade- quate answers to the questions of how forests should be managed in the future to maintain their basic functions and ecological services for current and future generations.
Broadening the mainly use-oriented perspec- tive in forestry and combining it with the knowl-
edge and expertise available from conservation and ecology is a critical step. This wider perspective will help forestry to better understand the com- plexity, diversity, and heterogeneity of forest eco- systems. In the long term, forest strategies that ignore the significance of these parameters for the functionality and integrity of forests will fail to sub- stantially contribute to climate change mitigation and to the adaptation of forests.
In its latest special report ‘Climate Change and Land Systems’ (IPCC 2019) the IPCC supports the view that sustainable forest management can sup- port adaptation to climate change while contribut- ing to the reduction of greenhouse gas emissions.
Such an opportunity should not be missed!
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Box B 1
Forestry can maintain and enhance biological diversity
T. Haußmann
Federal Ministry of Food and Agriculture (BMEL), national focal point for the European wide inte- grate network.
Our forests are ‘all-rounders’: they are sources of raw materials, climate change mitigators, wellness havens, habitats for countless animal and plant species, and much more. Covering 32 % of Ger- many, forests are a major feature of our country.
Maintaining and enhancing resilience, biologi- cal diversity, and the provision of broad ecosystem services in Europe’s forests based on people’s needs has become an ever-growing challenge for all actors including policy makers, forest owners, for- est managers, and nature conservationists. Against the background of climate change and the interna- tionally agreed development goals, the role of mul- tifunctional, professionally managed forests of Europe will remain an important mainstay in the coming decades. Achieving the multifunctionality objective for forests encompasses the necessity to connect people from forest management practice, science, and policy making. It also means we must learn lessons from other sectors and societal groups, and exchange experiences between countries.
Therefore, Germany supports the practice-orien- tated and science-based exchange of experiences under the European Network INTEGRATE (see Box B 2 in this book). This active contribution to implementing the EU Forest Strategy by further enhancing nature protection within sustainable forest management – i.e. supporting the criterion
“maintaining and enhancing forest-related biolog- ical diversity” – has gained increasing importance over the past years and offers an important basis for the coming years.
Seen from a national perspective and based on the National Forest Inventory, forestry in Germany is sustainable and multifunctional. One aim is to manage the forests as ‘close to nature’ as possible by using methods such as selection of mixed and site-adapted tree species, longer rotations, selec- tion cutting, and natural regeneration. Currently, at least 5 % of all forests are not used for forestry
purposes. The ecological value of the forests in Ger- many has improved significantly in recent decades.
The Red List of endangered biotope types of Ger- many also shows that development has stabilised in many forest biotopes. However, some forest ani- mal, fungus, and plant species are still deemed to be endangered, and some of these are even threat- ened with extinction. This applies in particular to species that are dependent on old-growth forests, undisrupted forest development, and old stands and deadwood. Other species, on the other hand, are dependent on historical forms of forest man- agement. It is, therefore, necessary to maintain a diversity of habitats and species, and further improve the ecological condition of forests with well-targeted and effective measures. Efforts to promote the further conversion of remaining sin- gle-species-stands into more resilient mixed forests need to be continued and scaled-up.
To this end, various positive approaches have already been documented within Germany as also presented in this publication. It is important to underline that those good practice forest enter- prises take advantage of the balance between enhancing the biodiversity while at the same time harvesting the renewable resource timber in a sus- tainable way. The use of timber still accounts for 95 % of the income of a forest owner and provides the society with this local ecological material. At the same time, the forests provide positive condi- tions for many species, some of them rare and endangered. If forest management is done care- fully and with particular attention paid to enhanc- ing nature protection, there is clear evidence that the species diversity in managed forests can be even higher than in unmanaged forests. In addi- tion, well-managed and accessible forests serve many other functions and can be very attractive for people, allowing visiting for recreation and sports and for supporting health recovery.
With this understanding: our forests are all- rounders.
Fig. 1. Dead and dying Norway spruce (Picea abies) patches in private forests: growing on the wrong sites, weakened by climate warming effects, and finally doomed to be killed by bark beetles. This is a frequent situation in Germany (upper photo). The lower photo shows the ‘optimal’ mixed forest consisting of at least three main tree species. Such forests are developing already in many areas since the conversion from monocultures to mixed forests is ongoing (Photos: Ulrich Wasem).
