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1.

Key message

Multi-objective robust decision making is a promising decision-making method in forest management under climate change as it adequately considers deep uncertainties and handles the long-term, inflexible, and multi-objective character of decisions. This paper provides guidance for application and recommendation on the design.

Context

Recent studies have promoted the application of robust decision-making approaches to adequately consider deep uncertainties in natural resource management. Yet, applications have until now hardly addressed the forest management context.

Aims

This paper seeks to (i) assemble different definitions of uncertainty and draw recommendation to deal with the different levels in decision making, (ii) outline those applications that adequately deal with deep uncertainty, and (iii) systematically review the applications to natural resources management in order to (iv) propose adoption in forest management.

Methods

We conducted a systematic literature review of robust decision-making approaches and their applications in natural resource management. Different levels of uncertainty were categorized depending on available knowledge in order to provide recommendations on dealing with deep uncertainty. Robust decision-making approaches and their applications to natural resources management were evaluated based on different analysis steps. A simplified application to a hypothetical tree species selection problem illustrates that distinct robustness formulations may lead to different conclusions. Finally, robust decision-making applications to forest management under climate change uncertainty were evaluated and recommendations drawn.

Results

Deep uncertainty is not adequately considered in the forest management literature. Yet, the comparison of robust decision-making approaches and their applications to natural resource management provide guidance on applying robust decision making in forest management regarding decision contexts, decision variables, robustness metrics, and how uncertainty is depicted.

Conclusion

As forest management is characterized by long decision horizons, inflexible systems, and multiple objectives, and is subject to deeply uncertain climate change, the application of a robust decision-making framework using a global, so-called satisficing robustness metric is recommended. Further recommendations are distinguished depending on the decision context.
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2.

•Introduction  

In the context of climate change, assessing climate–growth relationships is of high importance in order to understand how forest ecosystems evolve and to test climate models at regional scale.  相似文献   

3.

Context

We develop a modelling concept that updates knowledge and beliefs about future climate changes, to model a decision-maker’s choice of forest management alternatives, the outcomes of which depend on the climate condition.

Aims

Applying Bayes’ updating, we show that while the true climate trajectory is initially unknown, it will eventually be revealed as novel information become available. How fast the decision-maker will form firm beliefs about future climate depends on the divergence among climate trajectories, the long-term speed of change, and the short-term climate variability.

Methods

We simplify climate change outcomes to three possible trajectories of low, medium and high changes. We solve a hypothetical decision-making problem of tree species choice aiming at maximising the land expectation value (LEV) and based on the updated beliefs at each time step.

Results

The economic value of an adaptive approach would be positive and higher than a non-adaptive approach if a large change in climate state occurs and may influence forest decisions.

Conclusion

Updating knowledge to handle climate change uncertainty is a valuable addition to the study of adaptive forest management in general and the analysis of forest decision-making, in particular for irreversible or costly decisions of long-term impact.  相似文献   

4.

Introduction   

The aims of this study were to identify the climatic conditions controlling the distribution of Sasamorpha borealis and to assess the impact of climate change on the species in Japan.  相似文献   

5.

• Introduction   

Xeric (trailing) forest range limits are particularly vulnerable to impacts of predicted climate change. Regional modelling studies contribute to the identification of potential local climatic threats and may support appropriate management strategies.  相似文献   

6.

Context

In the context of climate change, several forest adaptation options have to be advocated such as a shift to more resistant species.

Aims

We provide an economic analysis of timber species change as a tool for adapting forests to climate change.

Methods

We use the framework of cost–benefit analysis, taking uncertainty into account both exogenously (sensitivity analysis) and endogenously [(quasi-)option value calculations]. We apply the method to assess the economic rationale for converting Norway spruce stands to Douglas-fir in the French Black Mountain.

Results

We find that the Douglas-fir conversion is land expectation value (LEV) maximizing under a wide range of a priori (subjective) probabilities attached to high mortality of Norway spruce under climate change (for probabilities higher than 0.25–0.31). If information about the impacts of climate change is expected to increase over time, and given the large sunk costs attached to conversion, a delay strategy may be preferable to transition and to status quo when the impacts of climate change on Norway spruce mortality are sufficiently ambiguous. In such cases, getting information earlier increases the LEV by €5–60/ha.

Conclusion

Beyond the specifics of the case study, this paper suggests that quasi-option value is a relevant tool to provide insights to forest owners dealing with adaptation decisions in the context of climate change.  相似文献   

7.

? Context

Walnuts (Juglans spp.) are ecologically and commercially important trees, yet synthesis of past and current research findings on walnut ecophysiology is lacking, especially in terms of potential acclimation to climate change.

? Aims

This study aims to (1) investigate walnut ecophysiology by comparing its attributes to associated deciduous angiosperms, (2) address potential acclimation of walnut to climate change, and (3) identify areas for prioritization in future research.

? Results

There is considerable uncertainty regarding the magnitude of potential effects of climate change on walnut. Some studies tend to indicate walnut could be negatively impacted by climate change, while others do not. Walnut may be at a disadvantage due to its susceptibility to drought and frost injury in current growing regions given the projected increases in temperature and extreme climatic events. Other regions that are currently considered cold for walnut growth may see increased establishment and growth depending upon the rate of temperature increase and the frequency and severity of extreme climatic events.

? Conclusion

Research investigating a combination of environmental factors, such as temperature, carbon dioxide, ozone, water, and nitrogen is needed to (1) better project climate change effects on walnut and (2) develop management strategies for walnut acclimation and adaptation to climate change.  相似文献   

8.

? Key message

Insurance might be an efficient tool to strengthen adaptation of forest management to climate change. A theoretical model under uncertainty is proposed to highlight the effect, on adaptation decisions, of considering adaptation efforts in forest insurance contracts. Results show that insurance is relevant to increase adaptation efforts under some realistic conditions on forest owner’s uncertainty and risk preferences, and on the observability or not of adaptation efforts.

? Context

One of the challenges of forest adaptation to climate change is to encourage private forest owners to implement adaptation strategies.

? Aims

We suggest the analysis of forest insurance contracts against natural hazards as a vector to promote the implementation of adaptation efforts by private forest owners.

? Methods

We propose a theoretical model of insurance economics under risk and under uncertainty.

? Results

Our results indicate that when climate change makes the probability of the occurrence of the natural event uncertain, then it may be relevant to include adaptation efforts in the insurance contract, leading to an increase in the adaptation efforts of risk-averse and uncertainty-averse forest owners. In addition, we show that the relevance of insurance as a vector to promote adaptation efforts is greater when the forest owner’s effort is unobservable by the insurer as compared to a situation of perfectly observable effort.

? Conclusion

Under some realistic assumptions, the forest insurance contract seems to be a relevant tool to encourage forest owners to adapt to climate change.
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9.
10.

Key message

Pertinence of alternative adaptation strategies to business as usual, namely reactive, active, and robust adaptation strategies, can be evaluated by incorporating the expected costs and benefits of adaptation, climate change uncertainty, and the risk attitudes of decision-makers.

Context

Forest management is used to coping with risky and uncertain projections and estimates. However, climate change adds a major challenge and necessitates adaptation in many ways.

Aims

This paper highlights the dependency of the decisions on adaptation strategies to four aspects of forest management: (i) the costs of mitigating undesirable climate change impacts on forests, (ii) the value of ecosystem goods and services to be sustained, (iii) uncertainties about future climate trajectories, and (iv) the attitude of decision-makers towards risk (risk aversion level).

Methods

We develop a framework to evaluate the pertinence of reactive, active, and robust adaptation strategies in forest management in response to climate change.

Results

Business as usual may still be retained if the value of the forest and cost of climate impacts are low. Otherwise, it is crucial to react and facilitate the resilience of affected forest resources or actively adapt in advance and improve forest resistance. Adaptation should be robust under any future climate conditions, if the value of the ecosystem, the impacts from climatic changes, and the uncertainty about climate scenarios are very high.

Conclusion

The decision framework for adaptation should take into account multiple aspects of forest management under climate change towards an active and robust strategy.
  相似文献   

11.

• Introduction   

Commercial thinning (CT) could contribute to increase short-term tree growth and be beneficial in a cold climate, as in boreal regions. Thus, growth rate, ring density and flexural modulus of elasticity (MOE) of trees may change after CT. Moreover, mechanical wood properties vary with position in the tree, and there is a need to develop optimal log allocation strategies in order to allocate logs to their best use.  相似文献   

12.

? Context

Two-thirds of Britain’s forest area is privately owned. Thus, understanding private forest owners and managers, and their attitudes to uncertainty and change, is essential for the success of climate change adaptation policies.

? Aim

The aims of this study are to (1) assess how beliefs in climate change in the private sector have influenced forest management practices; (2) identify constraints related to changes in species choice and silvicultural systems; (3) analyse the implications for implementing climate change policy in forestry.

? Method

Semi-structured interviews with key informants who provide advice to, or manage woodlands in, the private forest sector in north Wales.

? Results

Woodland managers and some advisers are not generally convinced of a need to adapt. They feel the future is uncertain, more usually in relation to tree disease than to climate change itself. Species choice is the principle focus of adaptation activities and reveals a deep divide in opinion. Commercial advisors look to new exotics but are inhibited by absence of markets, while small-scale owners rely more on native genetic diversity.

? Conclusions

Findings that are likely to apply widely include: the influential role of forest agents in forest management decisions including species choice; lack of confidence in climate change predictions, and in markets; more immediate concerns about tree pests and diseases; demand for leadership from the public sector, and for engagement amongst the private sector. Further research is needed across a wider area to test the variability in relationship between attitudes and behaviours, and local conditions including climate change predictions.  相似文献   

13.
Forest gap models are important tools for assessing the impact of global climate change on forest dynamics of tree species composition and size structure. In this study, the FAREAST gap model was used to examine the response of forest dynamics on Gongga Mountain, which is located on the southeastern fringe of the Tibetan Plateau, under three climate change scenarios. The simulated results showed that the climax community of the deglaciation slash would be mixed species of Picea brachytyla, Tsuga chinensis, and Pinus densata under climate change scenarios, as opposed to the pure Abies fabri forest under the current climate. Climate change also drove replacement of Populus purdomiis by Betula utilis, which became the most abundant pioneer tree species on the deglaciation slash. Under scenarios of climate change, three responses of the four typical forests distributed between 2200 and 3580 m above sea level are observed, such as dieback of today’s forest at 2200 and 3150 m, gradual change of the species composition at 2780 m, and afforestation at 3580 m. It is worth noting that the scenarios of climatic change are of inherent uncertainty, in the same way as the formulation of the ecological factors used in the models. It is suggested that simulations not be interpreted as predictions of the future development of the forest, but as a means of assessing their sensitivity to climate change. It is concluded that mountainous forests are quite sensitive to climate change.  相似文献   

14.

Key message

Natural disturbance can disrupt the anticipated delivery of forest-related ecosystem goods and services. Model predictions of natural disturbances have substantial uncertainties arising from the choices of input data and spatial scale used in the model building process, and the uncertainty of future climate conditions which are a major driver of disturbances. Quantifying the multiple contributions to uncertainty will aid decision making and guide future research needs.

Context

Forest management planning has been able, in the past, to rely on substantial empirical evidence regarding tree growth, succession, frequency and impacts of natural disturbances to estimate the future delivery of goods and services. Uncertainty has not been thought large enough to warrant consideration. Our rapidly changing climate is casting that empirical knowledge in doubt.

Aims

This paper describes how models of future spruce budworm outbreaks are plagued by uncertainty contributed by (among others): selection of data used in the model building process; model error; and uncertainty of the future climate and forest that will drive the future insect outbreak. The contribution of each to the total uncertainty will be quantified.

Methods

Outbreak models are built by the multivariate technique of reduced rank regression using different datasets. Each model and an estimate of its error are then used to predict future outbreaks under different future conditions of climate and forest composition. Variation in predictions is calculated, and the variance is apportioned among the model components that contributed to the epistemic uncertainty in predictions.

Results

Projections of future outbreaks are highly uncertain under the range of input data and future conditions examined. Uncertainty is not uniformly distributed spatially; the average 75% confidence interval for outbreak duration is 10 years. Estimates of forest inventory for model building and choice of climate scenario for projections of future climate had the greatest contributions to predictions of outbreak duration and severity.

Conclusion

Predictions of future spruce budworm outbreaks are highly uncertain. More precise outbreak data with which to build a new outbreak model will have the biggest impact on reducing uncertainty. However, an uncertain future climate will continue to produce uncertainty in outbreak projections. Forest management strategies must, therefore, include alternatives that present a reasonable likelihood of achieving acceptable outcomes over a wide range of future conditions.
  相似文献   

15.

Context

Understanding the range of possible climate change impacts on forests and the interactions between them is vital to sustainable forest management.

Aims

We examine whether the combined influence of climate change and timber harvest will affect tree species distribution and productivity beyond predictions based on climate alone.

Methods

We used the landscape disturbance model LANDIS-II to simulate two climate and two harvest scenarios in 14,000 ha of managed watersheds.

Results

The elevated temperature led to a decline in the abundance of boreal species and a substantial increase in some temperate and pioneer species. Importantly, the interaction of climate change and timber harvest yielded changes in the distribution of some species that would not be expected based on climate alone. Conversely, some late-successional species exhibited resistance to climate-driven changes in their distribution. Climate change caused an increase in forest productivity when harvest was simulated, but a decrease in no-harvest scenarios. A time lag in forest response was likely responsible for this decrease in the absence of widespread mortality.

Conclusions

The finding that disturbance may drive the range expansion of early-successional broadleaved species and cause a decline of red spruce has implications for forest community associations, as well as for forest management where conifers are favoured for pulp production.  相似文献   

16.

• Introduction  

Based on previous studies, it is assumed that the growth of Norway spruce (Picea abies) in southern Finland (61°N) may decrease under the changing climate due to the increasing soil water deficit, without management.  相似文献   

17.

• Introduction   

Siberian larch (Larix sibirica) has its southern distribution limit in Mongolia in an area of rapidly rising temperatures. Direct effects of climate on tree-ring formation due to drought stress or indirect effects via the control of insect herbivore populations are little studied.  相似文献   

18.

Context

Some forest insect pests are currently extending their range as a consequence of climate warming. However, in most cases, the evidence is mainly based on correlations and the underlying mechanism is not clearly known.

Aims

One of the most severe pests of pine forests in Europe, the pine processionary moth, Thaumetopoea pityocampa, is currently expanding its distribution as a result of climate warming and does not occupy entirely its potential habitat. A model describing its spread was developed to simulate its potential range in France under various climate change scenarios.

Methods

The spread model was divided into several sub-models to describe the growth, survival and dispersal of the species. The model was validated on the observed change of species distribution, its sensitivity was tested, and spread scenarios were simulated for the future.

Results

The model shows that climate warming initiated the species range expansion in France since the early 1990s. The spread is now limited by dispersal capability, but human-mediated dispersal could accelerate the range expansion.

Conclusion

Species range expansion is an indicator of climate change. However, time lags can appear due to limited dispersal capabilities, and human-mediated dispersal could create satellite colonies and artificially accelerate the spread.  相似文献   

19.

Introduction   

The reproductive phenology of plants is expected to be influenced by climatic factors and by the phylogenetic history of the species. In savannas, the peaks of flowering and fruiting are associated with climate seasonality. However, there is still a controversy about the reproductive phenology of plants in riparian forests, a vegetation type that does not experience a severe water shortage.  相似文献   

20.

? Context

Projecting changes in forest productivity in Europe is crucial for adapting forest management to changing environmental conditions.

? Aims

The objective of this paper is to project forest productivity changes under different climate change scenarios at a large number of sites in Europe with a stand-scale process-based model.

? Methods

We applied the process-based forest growth model 4C at 132 typical forest sites of important European tree species in ten environmental zones using climate change scenarios from three different climate models and two different assumptions about CO2 effects on productivity.

? Results

This paper shows that future forest productivity will be affected by climate change and that these effects depend strongly on the climate scenario used and the persistence of CO2 effects. We find that productivity increases in Northern Europe, increases or decreases in Central Europe, and decreases in Southern Europe. This geographical pattern is mirrored by the responses of the individual tree species. The productivity of Scots pine and Norway spruce, mostly located in central and northern Europe, increases while the productivity of Common beech and oak in southern regions decreases. It is important to note that we consider the physiological response to climate change excluding disturbances or management.

? Conclusions

Different climate change scenarios and assumptions about the persistence of CO2 effects lead to uncertain projections of future forest productivity. These uncertainties need to be integrated into forest management planning and adaptation of forest management to climate change using adaptive management frameworks.  相似文献   

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