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1.
Large forest estates actively participate in the marketing of timber in France. However, the marketing of wood from private and public large forest estates (over 25 ha) could be improved by better managing price risk in multiannual supply contracts of the timber industry: creation of compensation funds for forest owners or calls to financial markets linked to processed timber products for industrialists. But, the development of supply contracts does not mean that private or public auction procedures should be abandoned. Similarly, by supplementing “forest area development schemes”, it would be possible to increase the mobilisation of timber produced on small (1 to 10 ha) and medium (10 to 25 ha) forest estates: more forestry cooperatives or local forest agencies and a new timber pre-sale mode adapted to small forest estates are necessary (sales subject to the buyer's choice of purchasing standing timber or cut wood delivered to a depot by the seller).  相似文献   

2.

Key message

More and more environmental and resource economists are taking a particular interest in research on forest ecosystem services (FES), especially in a context of climate change. Spatial and temporal issues are crucial to economic analyses and for the design of conservation policies. Interdisciplinary research involving ecological and economic disciplines is a prerequisite for the more effective management of forest ecosystems.

Context

Economists define non-market ecosystem services (ES) as public or common goods due to their characteristics of non-rivalry in terms of consumption and/or non-excludability. Just because they do not have a price does not mean that ES have no economic value because their social benefits are undoubtedly considerable. These features, associated with the market demand for timber and a poor climate risk assessment, may lead to the under-provision of non-market forest ES and the over-harvesting of timber.

Aims

In this article, we review research questions that are central to the enhancement of FES provision. Beyond the economic modelling of the joint provision of FES, we focus on issues related to the design of public policies to guide forest management. The objective is to provide crucial insights concerning the importance of a spatial and sustainable provision of FES.

Results

First, we provide an economic interpretation of the FES concept and a review of economic models of forest management. Second, we explain how spatial and temporal dimensions of FES can have major implications on their supply and demand. Both dimensions explain why FESs have to be taken into account in production decisions and public policies (including the design of payment for environmental services (PESs)).

Conclusion

A better understanding of FES provision and public policies to be enhanced is not possible without accounting for spatial and temporal dimensions. This helps to analyse the impact of intervention on FES and the cost-effectiveness of economic instruments, implying a coordinated effort to bring together ecological and economic data and models.
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3.
This paper examines how Swedish forest owners’ associations are adapting their strategies to fit the changing needs of current and future members, and assesses how this development affects the organizations’ profile and relationship with members. To explore this issue eight semi-structured, face-to-face interviews with chairmen and senior managers from three associations and the Federation of Swedish Family Forest Owners were performed. Results showed that associations have identified an increasing need for management-support activities among members due to their decreasing familiarity with the basics of forestry. Help is increasingly needed both for setting up goals and objectives for their forest ownership, and to practically manage their properties. The associations’ education programmes are also being improved and adapted to suit members’ varying understanding of forestry by the introduction of A-, B- and C-level courses. Education campaigns have proved to be a successful tool for affecting members’ management objectives. Further, the associations see an increasing need for political activity to counter calls for stricter management regulations being made by the media, politicians and environmental organizations and thereby protect members’ ownership rights. Initiatives within the organizations for more efficient governance processes and the professionalization of working procedures within the member organizations may, however, come to reduce individual member involvement in the associations. Members may thus increasingly come to act as customers of service in their interaction with the organizations.  相似文献   

4.
The beginning of the land rent theory is closely related to the German forest economists Friedrich Wilhelm Leopold Pfeil and Johann Christian Hundeshagen (1828). It was further developed by Gottlob König (1864), Johann Heinrich v. Thünen, Max Robert Preßler, Gustav Heyer, Max Endres and in particular by Martin Faustmann (1849). His 1849 published and well known formula may be seen as the center of the land rent theory. However, the application of this concept demanded a considerable change of forest management practice due to the reduction of usual rotations and stocking density. Eventually, the land rent theory conflicted with the principle of sustained yield which had become the central idea of forestry in Germany in the 19th century. Since forestry under German conditions did not start as an investment on bare forest land, but had to manage existing forests under the principle of sustainability, the theory of the highest revenue seemed to be a more appropriate guideline for forestry. However, the maximization of the highest revenue assumed a marginal interest rate of 0% because the time span between input and output was not considered. Besides that, this principle also conflicted with the reality of forestry, because the scarcity of financial funds was not regarded. So far, both theories have not delivered solutions useful to real forest economic decision problems in Germany. Using an example from Lower Saxony, it is demonstrated that considering the objective of sustainability leads to results which are in accordance with the reality and the economic theory.  相似文献   

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Determining the physical and mechanical properties of soil and its behavior for engineering projects is essential for road construction operations. One of the most important principles in forest road construction, which is usually neglected, is to avoid mixing organic matter with road materials during excavation and embankment construction. The current study aimed to assess the influence of organic matter on the physical properties and mechanical behaviors of forest soil and to analyze the relation between the amount of organic matter and the behavior of forest soil as road material. A typical soil sample from the study area was collected beside a newly constructed roadbed. The soil was mixed with different percentages of organic matter(control treatment, 5, 10, and 15% by mass) and different tests including Atterberg limits, standard compaction, and California bearing ratio(CBR) tests were conducted on these different soil mixtures. The results showed that soil plasticity increased linearly with increasing organic matter.Increasing the organic matter from 0%(control) to 15%resulted in an increase of 11.64% of the plastic limit and 15.22% of the liquid limit after drying at 110 ℃. Also,increasing the organic matter content reduced the soil maximum dry density and increased the optimum moisture content. Increasing the organic matter from 0 to 15% resulted in an increase of 11.0% of the optimum moisture content and a decrease of 0.29 g/cm~3 of the maximum dry density. Organic matter decreased the CBR, which is used as the index of road strength. Adding 15% organic matter to the soil resulted in a decrease of the CBR from 15.72 to 4.75%. There was a significant difference between the two drying temperatures(60 and 110 ℃) for the same organic matter mixtures with lower water content values after drying at 60 ℃. The results revealed the adverse influence of organic matter on soil engineering properties and showed the importance of organic matter removal before excavation and fill construction.  相似文献   

7.
This article addresses the German debate on the issue of the common welfare designation of public forests. In the first part, drawing on two case studies, the political discourse on the issue is introduced. Two major competing ‘story lines’ can be made out that are both based on a long tradition of controversially discussed concepts of regulatory forest policy. While they both emphasise that common welfare services in forestry run counter to profit orientation, they fundamentally differ with regard to the consequences for forest policy, e.g., considering the degree of state intervention. Afterwards, an overview on the scientific debate on common welfare in the German context is given, and different concepts of common welfare determination are distinguished. Existing approaches of common welfare determination in German forest policy are related to these concepts and discussed. It is argued that the common welfare designation of the public forest is only insufficiently implemented by the actual governance arrangements. Based on this consideration, eventually, the implementation of a procedural concept of common welfare operationalisation in Germany’s public forests at the local level is proposed. While such a concept will not solve all complex problems related to the determination of common welfare in public forestry, it would notably contribute to a more operational definition of common welfare in public forestry and a more informed public debate on the issue.  相似文献   

8.
Poplars are one of the woody plants that are very sensitive to water stress, which may reduce the productivity of fast-growing plantations. Poplars can exhibit several drought tolerance strategies that may impact productivity differently. Trees from two improved hybrids, Populus balsamifera?×?Populus trichocarpa Torr. & Gray (clone B?×?T) and P. balsamifera?×?Populus maximowiczii A. Henry (clone B?×?M), having P. balsamifera L. as a parent and trees from native and unimproved P. balsamifera were subjected to a 1-month drying cycle in a growth chamber and then rewatered. The unimproved and native B clone maintained higher stomatal conductance (g(s)) than the hybrids, and high photosynthetic activity and transpiration, even when soil water content was nearly zero. As a result, both instantaneous water use efficiency (WUE(i)) and leaf carbon isotope composition (δ(13)C) indicated that this clone was less affected by drought than both hybrids at maximal drought stress. However, this clone shed its leaves when the drought threshold was exceeded, which implied a greater loss of productivity. The B?×?M hybrid showed a relatively conservative response to water stress, with the greatest decrease in transpiring versus absorbing surface (total leaf area to root biomass ratio). This clone was also the only one to develop new leaves after rewatering, and its total biomass production was not significantly decreased by drought. Among the two hybrids, clone B?×?T was the most vigorous, with the greatest transpiration (E(i)) and net CO(2) assimilation (A) rates, allowing for high biomass production. However, it had a more risky strategy under drought conditions by keeping its stomata open and high E(i) rates under moderate drought, resulting in a lower recovery rate after rewatering. The opposite drought response strategies of the two hybrids were reflected by clone B?×?T having lower WUE(i) values than clone B?×?M at maximal drought, with a very low Ψ(min) value of -3.2 MPa, despite closed stomata and stopped photosynthetic activity. Positive linear relationships between A and g(s) for the three hybrids indicated strong stomatal control of photosynthesis. Moreover, the three poplar clones showed anisohydric behaviour for stomatal control and their use under long-term drought should be of interest, especially the B?×?M clone.  相似文献   

9.
The National Institute of Food and Agriculture (NIFA) provided a grant to establish a wood-based cellulosic biofuels industry in the US Pacific Northwest. Whether the industry will be sustainable depends largely on social acceptability in general and market acceptability of the biofuels among the public in particular. We conducted contingent valuation surveys of general public in the US states of Oregon and Washington to determine people's willingness to pay (WTP) for wood-based cellulosic biofuels and the factors that influence their WTP decisions. Oregon has an existing cellulosic biorefinery, while Washington's biorefineries are only being planned, allowing us to conduct an ex-ante (Washington) versus ex-post (Oregon) WTP comparison. We sent out mail surveys to 2828 valid mailing addresses between May and July of 2015 and received 757 completed surveys. We used the distribution-free Turnbull estimator to estimate the expected WTP and logistic regression to determine the relative strength of predictors on WTP. About one fifth (18.8%) of the respondents were willing to pay some premium for wood-based cellulosic biofuels. The mean WTP amount was $0.19 ± $0.03/gal. (95% confidence interval: $0.17 to $0.21), which equates to a 6.4% price premium on top of the market price for gasoline. Logistic regression results showed that the offered bid price, knowledge on biofuels, age and religious affiliation of respondents were statistically significant predictors of WTP decisions. No significant differences in ex-ante versus ex-post WTP were observed. We also discussed the policy implications of these results for sustainable management of the wood-based cellulosic biofuels industry.  相似文献   

10.
For many years, we have observed a significant rise in urban population, the spatial development of cities, and an increase in urbanized areas. More and more people feel the need to have contact with nature. The interest in forest recreation is growing, though the forest is a serious source of allergenic plant pollen. The aim of the present study was to compare two forest types in the context of their recreational potential and the effect strength of aeroallergens. This study was conducted in SE Poland in a Nemoral Scots pine forest (RB) and in a Central European submountainous beech forest (TH). Their recreational potential was assessed. Samples of moss containing plant pollen were collected under the canopy, from forest clearings and forest edges as well as in an open area. Based on the number of pollen grains deposited in moss pollsters, the forest impact on humans was calculated. The recreational potential values for both sites studied are evidence of the high recreational suitability of these forests, but the recreational capacity of RB is lower compared to TH. Palynological analysis showed that the pollen deposition is higher in BR and that the plant pollen risk is lowest under the canopy, regardless of the forest type. The beech forest was found to be characterized by greater recreational potential and a weaker actual effect of pollen allergens than the pine forest. In assessing forest recreational potential, palynological data should form the basis for modification of the degree of recreational suitability. Such information would also be useful in controlling recreational traffic since, as we have proved, visiting appropriate places in a forest allows the exposure of allergen sensitive people to be reduced.  相似文献   

11.
New Forests - The original version of this article was inadvertently published without the acknowledgements section.  相似文献   

12.
Examining ecological limits to shade acclimation at whole-plant level is determinant for evaluating the success of sapling establishment in low-light environments. We studied nutritional effects on whole-plant development in response to shade in two Mediterranean forest tree species with different successional status: the early-successional Pinus halepensis Mill. and the late-successional Quercus pubescens Wild. Through a nursery-based factorial experimental design approach, we measured height increment along 2 years and final leaf, stem and root biomass in both species saplings subjected to two lights and two soil nutrient availability treatments. The shade avoidance response was exclusive to P. halepensis, appeared as timely dependent, and persisted longer in saplings exposed to higher nutrient availability. Q. pubescens benefited from the higher nutrient availability by lowering the light-driven plastic response in aerial support investment and belowground carbon allocation, whereas P. halepensis heightened its light-driven plastic response. These contrasted responses are thus clearly related to the shade acclimation strategy of each species: the shade-intolerant P. halepensis enhances shade avoidance when non-nutrient-limited, whereas the shade-tolerant Q. pubescens assumes a conservative strategy by limiting phenotypic plasticity-induced costs. Maintaining greater shade avoidance in non-nutrient-limited soil conditions might be an adaptive advantage for P. halepensis seedlings growing in the understory, in response to gap formation in the overstory. In contrast, the more conservative and less costly shade responsiveness of Q. pubescens may confer it a better adaptive advantage in long-term light-limited environments.  相似文献   

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16.
Decision support systems (DSSs) are important in decision-making environments with conflicting interests. Many DSSs developed have not been used in practice. Experts argue that these tools do not respond to real user needs and that the inclusion of stakeholders in the development process is the solution. However, it is not clear which features of participatory development of DSSs result in improved uptake and better outcomes. A review of papers, reporting on case studies where DSSs and other decision tools (information systems, software and scenario tools) were developed with elements of participation, was carried out. The cases were analysed according to a framework created as part of this research; it includes criteria to evaluate the development process and the outcomes. Relevant aspects to consider in the participatory development processes include establishing clear objectives, timing and location of the process; keeping discussions on track; favouring participation and interaction of individuals and groups; and challenging creative thinking of the tool and future scenarios. The case studies that address these issues show better outcomes; however, there is a large degree of uncertainty concerning them because developers have typically neither asked participants about their perceptions of the processes and resultant tools nor have they monitored the use and legacy of the tools over the long term.  相似文献   

17.
Rainforest deforestation and subsequent reforestation not only alter above-ground vegetation, but also lead to significant changes in the physical and chemical characteristics of soil and in biochemical cycles, which in turn are likely to influence the growth of rainforest plants. However, little research has directly linked soil condition to seedling growth under different forms of rainforest restoration.  相似文献   

18.
Yellow cypress (Chamaecyparis obtusa (Siebold & Zucc.) Endl. var. formosana (Hayata) Rehder) is the predominant tree species of Taiwan's nutrient-poor, mountain fog forests. Little is known about the potential contribution of solute uptake from fog to the overall nutrition of these trees. Shoots of yellow cypress seedlings were misted with artificial fog containing the tracer rubidium (Rb) in laboratory and field experiments to determine if there is solute uptake from the fog. After misting shoots for six weeks, substantial amounts of tracer were detected in unexposed roots by inductively coupled plasma mass spectroscopy bulk analysis. Possible routes of entry were examined by element imaging with energy dispersive X-ray analysis. Direct uptake of the tracer into leaves across the cuticle and epidermis was small, excluding this as the major uptake path. Accumulations of Rb were found on leaf surfaces along the edges of the leaves. The almost daily changes in fog coverage and air humidity may enhance the accumulation of fog solutes at leaf edges. Accumulation of Rb was also found in narrow clefts between opposite leaves and between the outermost and underlying alternating stacked leaves. The clefts provide a direct passage from the leaf surface to the space beneath the imbricate leaves and the underlying alternate leaves, possibly facilitating solute uptake from fog, which in turn may contribute to the nutrition of yellow cypress.  相似文献   

19.
New Forests - Light is the most important physical variable that affects patterns of biomass allocation. A quantitative understanding of biomass allocation patterns is crucial to quantifying...  相似文献   

20.

We examined the association between habitat variables and the relative impacts of topographic microclimates as a valuable tool for restoration and conservation of Abies pinsapo in southern Spain. We used presence–absence data from A. pinsapo and 79 environmental variables and biomod species distribution models to describe the current and future species habitat across the Sierra de las Nieves Natural Park (southern Spain). A. pinsapo habitat was most strongly associated with microtopographic (solar incidence) and temperature variables, indicating climate-driven changes in microhabitat use. Most of the temperature variation among the study site was attributable to topographic microclimates rather than regional temperature differences, such that differences in microhabitat associations occurred principally between north- and south-facing slopes within the same region. The current potential distribution suggests that around 8.7% (56.44 km2) of the study area is highly suitable for A. pinsapo, with 9.7% (62.84 km2) being moderately suitable. Under different global circulation models and climate change scenarios, the net decrease in suitable habitat is predicted to be 93% of the current distribution by 2040, disappearing altogether by 2099. Our findings also show a sharp reduction of potential restoration areas (1.8% of the current areas). Microclimatic variation generated by the topography offers the microclimate-driven locations of habitat suitability which could shape species’ distribution restoration actions and their responses to environmental change. The approach presented here can provide a rapid assessment of the future conservation status of other important forest tree species in Spain, improving our understanding of the vulnerability of endangered species under climate change, and can be an effective tool for biodiversity conservation, restoration, and management.

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