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1.
To study whether, why, and how forestry decision-makers in Southeastern Norway adapt to climate change, we conducted a series of semi-structured interviews in focus groups consisting of non-industrial private forest owners, forest managers, and forest advisors. Our results show that a majority of the participants believed in climate change as a phenomenon, and had experienced events or observed changes that they attributed to climate change. However, we found little evidence of concern regarding climate change impacts on forest ecosystems and forestry among the participants. Instead, the majority regarded climate change more as an opportunity for the Norwegian forest-based sector than a threat. A minority had implemented proactive practices motivated by climate change but in all but one case, the adjustments were adaptation of forest infrastructure. In general, the participants agreed that the uncertainty associated with the effects of climate change and the (economical) uncertainty associated with adaptation of forest ecosystems were too large to change forest management practices at present. However, many participants, in particular the managers, are already adapting in response to experienced problems, such as increased frequency and duration of periods with low carrying capacity of the ground implying reduced or no accessibility within and to stands.  相似文献   

2.
In the aftermath of a hurricane in Sweden that felled some 250 million trees, the Swedish Forest Agency advised forest owners to reduce forest vulnerability by planting different tree species. This paper analyses why forest owners failed to heed the Forest Agency's recommendation, thereby reproducing a forest vulnerable to storms. This paper focuses on the deliberations and risk evaluations of forest owners when deciding which tree species to plant. The analysis identifies three main categories of reasoning that guided the forest owners' decision-making process: short-term economic reasoning caused by the pressing situation they faced; an understanding of windstorms as natural catastrophes that are impossible to influence; and the uncertainties associated with alternative forest management practices. Furthermore, given their risk-averse strategy, their approach to understanding and coping with uncertainty was crucial in determining their responses. This paper concludes that the forest owners primarily employed experience-based, practical and embodied knowledge, implying that abstract risks and theoretical knowledge regarding future developments were not deemed relevant. An additional conclusion is that even if a huge storm felling shows the need to change forest management practice, it does not provide the most favourable social conditions for achieving change.  相似文献   

3.
Above ground dry mass production and N accumulation on an areal basis in stems, branches and needles as well as in litterfall in a Norway spruce stand in south Sweden treated with unlimited availability of water and nutrients (fertilisation with irrigation) or of water (irrigation) during a 6 year experimental period are presented. Fertilisation was made in liquid form on a weekly basis during the vegetation period with 100 kg N ha−1 year−1 during each year. The fertiliser also included a balanced composition of P, K, Ca, Mg and S as well as of micronutrients. Irrigation was carried out as soon as a 20 mm water storage deficit developed. It is concluded that there is a large potential to improve Norway spruce production through liquid fertilisation with irrigation. Stem and branch production of Norway spruce was almost doubled due to this treatment. Also, stand needle dry mass and litterfall were markedly increased in comparison with the control. Water and N availability were the two most limiting growth factors. During the experimental period, irrigation had a greater effect on growth than N addition. The gross N uptake increased by 450 kg ha−1 as a result of 600 kg ha−1 fertiliser addition. Needle retention was increased for irrigated trees but needle litterfall remained unchanged. Changing the forest management of Norway spruce to intensive cultivatation results in transitional carbon sequestration in both stand and soil compared with an untreated ecosystem. The largest long-term environmental value is, however, achieved if this cultivated renewable biomass is used as a substitute for fossil fuels. Wood utilisation options of intensively cultivated Norway spruce are discussed.  相似文献   

4.

? 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.
  相似文献   

5.

? 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   

6.
Collaborative forest management (CFM) is a joint forest management approach between government and community. It covers distant communities too, who live out of 5-km periphery of the forest and involves them in forest management. This paper assesses whether the distant communities are deriving benefits from CFM in the form of timber, fuelwood and fodder. A total of 350 households was surveyed using a structured questionnaire. The result indicated that distant users were getting more timber compared to the users who lived close to collaborative forest and it was opposite in case of fuelwood and fodder. About 75% and 85% of fuelwood and fodder needs was fulfilled from the private source- trees grown on private farmland. Although CFM approach is able to supply timber to distantly located households, rich and male-headed households are disproportionately receiving high benefits. Provisioning small timber to the poor for house construction in place of sawn timber which is very expensive, may enhance welfare of the poor.  相似文献   

7.
Conversion of natural secondary broad-leaved forest to Cunninghamia lanceolata plantation is a common management practice in subtropical China. In this study, we compared soil physico-chemical properties, microbial biomass in one natural secondary broad-leaved forest and two C. lanceolata plantation sites to estimate the effects of forest conversion on soil microbial biomass at the Huitong Experimental Station of Forestry Ecology, Chinese Academy of Sciences. Concentrations of soil organic carbon, total nitrogen, NH4^+-N and microbial biomass carbon and nitrogen were much lower under C. lanceolata plantations as compared to natural secondary broad-leaved forest. Soil microbial biomass C in the first and second rotation of C. lanceolata plantations was only 53%, 46% of that in natural secondary broad-leaved forest, and microbial biomass N was 97% and 79%, respectively. The contribution of microbial biomass C to soil organic C was also lower in the plantation sites. However, the contribution of microbial N to total nitrogen and NH4^+-N was greater in the C. lanceolata plantation sites. Therefore, conversion of natural secondary broad-leaved forest to C. lanceolata plantation and continuous planting of C. lanceolata led to the decline in soil microbial biomass and the degradation of forest soil in subtropical China.  相似文献   

8.
Seasonal patterns of wood formation(xylogenesis) remain understudied in mixed pine-oak forests despite their contribution to tree coexistence through temporal niche complementarity.Xylogenesis was assessed in three pine species(Pinus cembroides,Pinus leiophylla,Pinus engelmannii) and one oak(Quercus grisea) coexisting in a semi-arid Mexican forest.The main xylogenesis phases(production of cambium cells,radial enlargement,cell-wall thickening and maturation) were related to climate data consideri...  相似文献   

9.

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.
  相似文献   

10.
Some Eucalyptus species are widely used as a plantation crop in tropical and subtropical regions. One reason for this is the diversity of end uses, but the main reason is the high level of wood production obtained from commercial plantings. With the advancement of biotechnology it will be possible to expand the geographical area in which eucalypts can be used as commercial plantation crops, especially in regions with current climatic restrictions. Despite the popularity of eucalypts and their increasing range, questions still exist, in both traditional planting areas and in the new regions: Can eucalypts invade areas of native vegetation, causing damage to natural ecosystems biodiversity?The objective of this study it was to assess whether eucalypts can invade native vegetation fragments in proximity to commercial stands, and what factors promote this invasive growth. Thus, three experiments were established in forest fragments located in three different regions of Brazil. Each experiment was composed of 40 plots (1 m2 each one), 20 plots located at the border between the forest fragment and eucalypts plantation, and 20 plots in the interior of the forest fragments. In each experimental site, the plots were paired by two soil exposure conditions, 10 plots in natural conditions and 10 plots with soil exposure (no plant and no litter). During the rainy season, 2 g of eucalypts seeds were sown in each plot, including Eucalyptus grandis or a hybrid of E. urophylla × E. grandis, the most common commercial eucalypt species planted in the three region. At 15, 30, 45, 90, 180, 270 and 360 days after sowing, we assessed the number of seedlings of eucalypts and the number of seedlings of native species resulting from natural regeneration. Fifteen days after sowing, the greatest number of eucalypts seedlings (37 m−2) was observed in the plots with lower luminosity and exposed soil. Also, for native species, it was observed that exposed soil improved natural germination reaching the highest number of 163 seedlings per square meter. Site and soil exposure were the factors that have the greatest influence on seed germination of both eucalypt and native species. However, 270 days after sowing, eucalypt seedlings were not observed at any of the three experimental sites. The result shows the inability of eucalypts to adapt to condition outside of their natural range. However, native species demonstrated their strong capacity for natural regeneration in forest fragments under the same conditions where eucalypts were seeded.  相似文献   

11.
12.
13.
Bark beetle dispersal and host selection behaviour are a complex and poorly understood process, resulting in specific spatio-temporal infestation patterns in forests. Aerial images from the Bavarian Forest National Park (Germany) provide a high-resolution, that is, tree-scale data set for the period 2001–2010, including information about Ips typographus (Col., Curculio., Scolytinae) infestation, the application of sanitary logging, natural forest edges and the area of living spruce susceptible to bark beetle infestation. We combined methods of GIS and image analysis to investigate the infestation probabilities at three types of forest edges under spatial and temporal aspects and compared them to the corresponding probabilities at the stand interior. Our results showed a pronounced infestation predisposition of such edge trees delimiting infestation patches cleared by sanitary logging measures, in particular at the south-facing edge sector. In contrast, edges adjacent to non-cleared infestation were revealed as less attractive for subsequent infestations, but nonetheless more attractive than permanent forest edges or the stand interior. Additionally, we measured near-bark surface air temperature to determine microclimatic differences at those edge- or non-edge sites and related them to predisposition results. Finally, our study emphasized favourable microclimatic conditions—summarized as the “sun-effect”—as a decisive factor enhancing the local infestation probability at recent forest edges in multiple ways. Both insect- and host tree-related reactions to suddenly altered microclimate are supposed to bias arbitrary colonization behaviour at patch and tree level, thereby mainly explaining observed infestation patterns. From the forester’s point of view, our results may contribute to precise bark beetle risk assessment and thus facilitate decision making in forest management.  相似文献   

14.

• Context  

Forest stand dynamics models simulate the growth of trees in stands; based on field measurements and system knowledge, they provide a relatively precise representation of forest growth and are well adapted for forest management purposes. Architectural models describe the structure of plants according to ontogenetic development processes; as a support of biomass production and partitioning at organ scale, they simulate individual tree development.  相似文献   

15.
Abstract

Norwegian forest policy has high-level, complex objectives for the products and benefits from the forest, including increased contribution to the climate, preservation of biodiversity, and creation of economic values. In Norway, it is first and foremost small-scale private forest owners who have to deliver on these expanded goals. The article reveals owners’ lack of forestry competence, and elaborates on the role of forestry employees (advisers) in owners’ decision-making processes, be it forestry-competent owners or not. There is, however, a decreased number of advisers in the private and public forest services, implying that forest owners are atomised in the meaning of being alone. This type of individualization and an increasing lack of forestry competence among forest owners are a contradiction. The mismatch is serious for the government and the forestry business because it probably hampers the fulfilment of the political objectives. The article presents six options for meeting the obstacles to goal fulfilment. The article is based on two research projects from the counties of Trøndelag and Hedmark. Data were collected between 2002 and 2007 and include survey, focus group interviews, in-depth interviews, fieldwork and document analysis.  相似文献   

16.
An expert on local flora usually is the best option for plant species selection in most ecological restoration projects; although species selection often needs to be dealt with swiftly as well as on a limited budget, and obtaining the opinion of a local expert may not always be an economically viable alternative. In such cases, species distribution models (SDM) may offer a faster and more cost effective alternative. We asked six experts to rank native tree species according to their suitability at 24 forest sites. The predictive performance of the suitability rankings was evaluated by assessing their ability to discriminate present from absent species in the observed tree assemblages at each evaluation site. We used the area under the receiver operating characteristic curve to calculate the probability that the estimated suitability for a species present at a particular evaluation site is greater than the estimate for an absent species (both picked at random). Suitability rankings were also obtained from the predictions of SDM and the same procedure was used to estimate the predictive performance of the set of models at each site. The experts offered concordant suitability rankings at almost every evaluation site. There were no significant differences in the predictive performance of the SDM and four of the experts, although the SDM performed slightly better than the other two experts. Our results point to the suitability of the proposed species distribution modeling approach to obtain fast and cost effective recommendations for species selection in forest restoration projects.  相似文献   

17.
Swedish forest growth can be increased through intensive forestry practices, enabling an increased use of forest biomass for climate-change mitigation. However, the diffusion of such practices depends on the forest owners’ adoption of them. We study Swedish private forest owners’ perceptions and intentions with respect to increasing forest growth by adopting exotic tree species. The results of a mail-in questionnaire survey show that although a majority of forest owners desire increasing forest growth, most owners have only a basic understanding of exotic tree species and a smaller proportion is interested in adopting them. The intention to adopt exotics seems to depend on the perceived performance of the species with respect to the economic aspects of forest management rather than on environmental or recreational concerns. Whereas a knowledge gap among the private forest owners regarding how to increase forest growth is implied, forest owners with higher self-rated knowledge of forestry and exotics have stronger intentions to adopt such species.  相似文献   

18.
Forest rehabilitation activities within centrally controlled state-owned forests in Ethiopia could not deliver communities with increased income. A study aiming to assess the benefits of forests for smallholder farmers whose land falls close to the state forest was conducted in Hugumbirda and Endedo kebele, two villages located adjacent to the Hugumbirda forest. Semi-structured questionnaires were used to collect data from 251 randomly selected households living near or adjacent to the state forest. A logit model was used to analyze factors affecting household’s willingness to scale up forests at the communal level. Most of the respondents living near or adjacent to the national forest were found to be dependent on the forest for fuelwood and therefore energy, timber products, and farming equipment. Furthermore, households were found to perceive that communal intervention management is a significant factor in attempts to further scale up forests. Scale-up of forests at the community was one option to enhance the vegetation cover and therefore increase primary production by promoting infiltration and decrease evaporation and runoff water. Finally farmers have suggested the state forest should be devolved to the community to improve the current level of forest contributions to the livelihood of smallholder farmers.  相似文献   

19.
Accurately estimating forest net primary productivity (NPP) plays an important role in study of global carbon budget. A NPP model reflecting the synthetic effects of both biotic (forest stand age, A and stem volume, V) and climatic factors (mean annual actual evapotranspiration, E) was developed for Chinese pine (Pinus tabulaeformis) forest by making full use of Forest Inventory Data (FID) and dynamically assessing forest productivity. The NPP of Chinese pine forest was estimated by using this model and the fourth FID (1989–1993), and the spatial pattern of NPP of Chinese pine forest was given by Geography Information System (GIS) software. The results indicated that mean NPP value, of Chinese pine forest was 7.82 t m−2·a−1 and varied at the range of 3.32–11.87 t hm−2·a−1. NPP distribution of Chinese pine forests was significantly different in different regions, higher in the south and lower in the north of China. In terms of the main distribution regions of Chinese pine, the NPPs of Chinese pine forest in Shanxi and Shaanxi provinces were in middle level, with an average NPP of 7.4 t hm−2·a−1, that in the southern and the eastern parts (e.g. Shichuang Hunan, Henan, and Liaoning provinces) was higher (over 7.7 t hm−2·a−1), and that in the northern part and western part (e.g. Neimenggu and Ningxia provinces) was lower (below 5 t hm−2·a−1). This study provides an efficient way for using FID to understand the dynamics of foest NPP and evaluate its effects on global climate change. Foundation item: This study was supported by the National Natural Science Foundation of China (Nos. 30028001, 49905005), National Key Basic Research Specific Foundation (G1999043407); the Chinese Academy of Sciences (KSC2-1-07). Biography: ZHAO Min (1973-), female, Ph. D. in Laboratory of Quantitative Vegetation Ecology, Institute of Botany, the Chinese Academy of Sciences, Beijing 100093, P. R. China. Responsible editor: Zhu Hong  相似文献   

20.
This study examined rural peoples’ intention to adopt sustainability practices in communally managed forests in Vhembe district, South Africa, using the theory of planned behavior as a conceptual framework. A total of 155 respondents were surveyed. The data was analyzed using structural equation modeling (SEM). The results showed that rural people have a strong intention to adopt sustainable forest-use and management practices. Out of the three constructs comprising the theory of planned behavior, subjective norm (SN) and attitude to behavior (AB) positively correlated with intention, with SN having the strongest influence on intention. Perceived behavioral control (PBC), which is the third construct, negatively correlated with intention. The study indicates that respondents’ subjective belief about the approval or disapproval of sustainable forest management (SFM) practices by other relevant people mainly influenced their intention to adopt or not adopt such practices. Thus, strategies and policies to enhance the sustainable management of communally owned forests in South Africa need to consider local actor contexts and sociocultural norms and values. In this regard, the engagement of influential people at the community level, and the demonstration of the short- and long-term benefits of sustainable forest use and management practices offer promising entry points.  相似文献   

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