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1.
The relationship between private forest investments and public cost sharing (government financial aid to private investment projects) was first analysed with an economic optimization model. In the general case the model predicted that cost-sharing causes substitution between private funding of investments and public aid. However, in some special cases complementarities were not ruled out. Next, the model predictions were tested with a translog cost function specification of forest investment fund shares. Aggregate data from Finland in years 1963–2000 were used. The substitution and own price elasticities of purely private, subsidized individual and subsidized collective investments are derived from maximum likelihood estimates of translog system model, allowing for investment scale effects. Investments supported by public funding behave in a strongly complementary fashion to each other. Some substitution of subsidized private funding for non-subsidized private funding was found. Strong scale effects and forest investment incentives were found among forest owners in response to public investment aid.  相似文献   

2.
Abstract

Similar to other industrialized countries, the USA has experienced a significant increase in the number of non-industrial private forest (NIPF) owners as well as shifts in the values held by these owners. This study examines the motivations of predominantly new ex-urban forest owners interested in forest management in pursuing collective action through participation in the now out-of-business Sustainable Woods Cooperative (SWC). While common elsewhere, forest landowner cooperatives in the USA are an anomaly. Through a case-study design that depended primarily on semi-structured interviews, it was found that SWC members were motivated to join SWC as it was an attractive alternative to (1) the typical timber sale scenario that often places the forest owner at a disadvantage, and (2) the primary government tax incentive program. SWC represents a shift towards owners playing a greater role in shaping forest practices and markets, which is generally absent in the USA. It also suggests that new ex-urban forest owners, who are found in most industrialized countries, will seek to reshape the forest policy arena to meet their values and objectives. As such, this study provides insights for others in understanding the potential changes wrought by the changing characteristics of forest owners.  相似文献   

3.

? 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   

4.
5.
European Journal of Forest Research - Drought in the forest is not only a prolonged state of water shortage, but also an occasion where interactions between plants and fungi are affected. Water...  相似文献   

6.
–  • Forest science and policy have experienced significant changes under the pressure of global change. Assuming that scientific publications mirror contemporary issues, our objective was to verify whether titles of articles show a temporal trend, and whether it coincides with the new agenda set by sustainable forest management.  相似文献   

7.
Many studies have recently been devoted to the study of landscape change, and some have even focused on an analysis of the dynamics of forest cover change. However, few of the studies have worked on a methodology for making a detailed investigation of long-term forest change dynamics based on historic cartographic sources. The goal of this study is to further develop a method for analyzing long-term changes in forest cover on the basis of old maps and orthophoto maps in the GIS environment. The study area is located in Central Bohemia, to the east of Kutná Hora, a UNESCO World Heritage Site. The area consists of 21 cadastral units with a total area of 113 km2. The maps of the First (1780), Second (1851) and Third Military Surveys (1877) and the present-day orthophotomap (2007) of the Czech Republic were used as data resources. Source data have been processed in GIS. Forest cover is the subject of our study. However, the term is perceived from a broader perspective. What we call forest cover in our study refers to forest wood elements and other wood species in the landscape. In this study, forest cover has been structurally considered as a whole, without dividing it into the two categories mentioned. We counted the extent of the forest cover in each particular time horizon in hectares and as a percentage of the area under study, also the absolute changes in forest cover between the individual time horizons in hectares as well as the intensity of the changes in forest cover in hectares per year. The spatial changes in forest cover were evaluated in a GIS environment using specialized features to analyze spatial variation. The forest cover occupied 16.60% (1,880 ha) of the total area in the First Military Survey (1780). In 2007, the proportion was slightly higher at 16.64% (1,884 ha). More than half of all forest land (53%) from the time of the Second Military Survey (1851) survived until 2007. Not only the information on absolute changes but also the information on the rate of change is of great importance. The old Military Survey maps and the orthophotomap enable us to carry out studies of long-term changes in forest cover. However, the geodetic inaccuracy of the First Military Survey maps precludes reliable and exact quantification of the landscape changes between the First Military Survey and the Second Military Survey, and also between the First Military Survey and present-day (orthophoto map). These maps cannot be used for evaluating forest cover changes on the level of individual plots. The method presented in our paper may contribute to a better understanding of the long-term dynamics of forest land, covering a period of more than 250 years. This knowledge can be applied in forest management planning procedures. Apart from their application in forestry, the methods presented in this study may be of interest for historians and biologists.  相似文献   

8.
How can we accommodate the diversity in tree species and sizes in mixed-species/size/age stands in the sustainable management of natural forests and woodlands in Africa for diverse timber and non-timber forest products and services, and during rehabilitation of degraded forests? The evergreen moist tropical to warm-temperate forests, from the equator to 34°S, generally function through relative shade tolerance. The tropical, strongly seasonal, drier deciduous woodlands generally function through adaptation to fire and/or grazing/browsing. Silvicultural systems, when implemented, are often not aligned with the ecological characteristics of the particular forest systems or the specific targeted species. This paper presents the concept of using the basic disturbance–recovery processes, with recovery development via stand development stages, as the basis for the development of silvicultural systems suitable for maintenance of forest complexity. Grain analysis and stem diameter distributions, analysed from resource inventories, are used to determine the specific shade- or fire-tolerance characteristics of key economical and ecological tree species. The gained knowledge of the ecosystem and species characteristics (including modes of regeneration, i.e. from seed or vegetative regrowth) and processes is used to simulate the ecological disturbance–recovery processes through the development of mixed silvicultural systems, such as a single-tree selection system, a group felling system and a coppice management system in the same forest. Very similar concepts are used to develop rehabilitation strategies to recover the processes towards regrowth stands of diverse species and structure: through stands of introduced plantations and invader tree species; and through early regrowth stages in deciduous woodlands and evergreen forests, after fire, slash-and-burn traditional agriculture, charcoal production or open-cast mining.  相似文献   

9.
Determining forest structural complexity,i.e.,a measure of the number of different attributes of a forest and the relative abundance of each attribute,is important for forest management and conservation.In this study,we examined the structural complexity of mixed conifer–broadleaf forests by integrating multiple forest structural attributes derived from airborne Li DAR data and aerial photography.We sampled 76 plots from an unmanaged mixed conifer–broadleaf forest reserve in northern Japan.Plot-level metrics were computed for all plots using both field and remote sensing data to assess their ability to capture the vertical and horizontal variations of forest structure.A multivariate set of forest structural attributes that included three Li DAR metrics(95 th percentile canopy height,canopy density and surface area ratio) and one image metric(proportion of broadleaf cover),was used to classify forest structure into structural complexity classes.Our results revealed significant correlation between field and remote sensing metrics,indicating that these two sets of measurements captured similar patterns of structure in mixed conifer–broadleaf forests.Further,cluster analysis identified six forest structural complexity classes includingtwo low-complexity classes and four high-complexity classes that were distributed in different elevation ranges.In this study,we could reliably analyze the structural complexity of mixed conifer–broadleaf forests using a simple and easy to calculate set of forest structural attributes derived from airborne Li DAR data and high-resolution aerial photography.This study provides a good example of the use of airborne Li DAR data sets for wider purposes in forest ecology as well as in forest management.  相似文献   

10.
In mixed angiosperm–conifer forests worldwide, infrequent landscape-level catastrophic disturbances create a mosaic of persistent and different aged forest stands in the landscape with varying levels of dominance by the conifer component. In the ‘temporal stand replacement model’ (TSRM), disturbance creates conditions favouring a colonising cohort that is replaced by a suite of relatively shade-tolerant canopy species, which establish following the synchronous senescence of the pioneer canopy. In most southern hemisphere mixed angiosperm–conifer forests, with the exception of those in southern Africa, the establishing cohort is usually a large and very long-lived (550–650 years) conifer that is gradually replaced by angiosperms. As an explanation of the apparent dominance of the conifer Podocarpus latifolius, we examine the efficacy of the TSRM in mixed Afrotemperate forests where the establishing cohort is not a conifer. Forest succession in Afrotemperate forests was deterministic with the successive replacement of species determined first by their establishment success in shaded environments, and second, by their relative longevity. Several angiosperm species that were common canopy dominants established a pioneer cohort but were gradually replaced by P. latifolius, a shade-tolerant species. Continuous regeneration beneath the angiosperm canopy by P. latifolius eliminates synchronous canopy senescence, a key feature of the TSRM, as a mechanism driving the temporal replacement of canopy species. Senescing angiosperms created canopy gaps that were colonised by grasses and ferns, which suppressed canopy tree regeneration. In contrast, with continuous regeneration beneath the shaded canopy, P. latifolius gains a critical advantage over angiosperms at gap formation. Thus, in the absence of fairly large-scale natural disturbances, conifers come to dominate Afrotemperate forests. Commensurate with the latter, conifers in Podocarpus-forest were dated to approximately 320 years, more than 100 years older than the oldest P. latifolius in angiosperm-dominated forest. Tree life-history differences (shade tolerance, longevity) and the time since disturbance drive successional change from an angiosperm-dominated system to a stage dominated by P. latifolius. In general, the TSRM is a plausible explanation for the observed canopy tree structure and dynamics in mixed Afrotemperate forests. South African Afrotemperate forest is unusual among other southern hemisphere mixed angiosperm–conifer forests in that a suite of angiosperm canopy species, rather than a single conifer species, forms the colonising cohort.  相似文献   

11.

The trade-offs between tree growth and mortality are important indicators of the life-history strategies of species and have been demonstrated to be maintained by inherent fitness differences among species. There is a growing consensus that functional traits which inflect the ecological performances of individuals may be correlated with growth–mortality trade-offs within communities. In this study, the aforementioned trade-offs were detected and their relationships with the functional traits were examined, based on data collected in a typical temperate forested area in northeastern China. Principal components analyses were performed for growth–mortality trade-off relationships. The factor scores on the first principal component were used to represent the species’ positions at an axis of life-history variations among different species. Correlation and multiple regression analyses were performed for the purpose of detecting the relationships between functional traits and the growth–mortality trade-off. The results showed that there were significant trade-offs between the tree growth and mortality rates in the examined plot. Among the six functional traits which were considered, the Hmax was found to have the strongest effects on the demographic rates and trade-offs. The observed negative effects on the tree growth and mortality rates suggested that the large species often grow more slowly and living longer, while species at small adult size grow fast but die easily. It was also observed that the specific leaf area and the leaf carbon content level were also very important to the growth and mortality trade-offs. The traits considered in this study explained 68% of interspecific variations in the species positions in the growth–mortality trade-off. In addition, wood density was found to show no effect on the trade-off. This was likely due to the fact that the density of the wood may influence the demographic rates more strongly during the early life stages of the trees. The results of discrimination analysis further confirmed the explanations abilities of the functional traits on the variations of life-history strategies among the species. Due to the fact that the relationships between the functional traits and the trade-offs were found to be relatively variable, it will be necessary to further consider other traits which are more closely and mechanistically linked to individual performances in future investigations, such as leaf life span, leaf tissue density, photosynthetic capacity, and dark respiration rates.

  相似文献   

12.
Abstract

This study describes forest landscape fragmentation and connectivity along the Finnish–Russian border near the Karelian Isthmus. The landscape pattern was analysed using classification data based on Landsat ETM+ and Landsat TM images in combination with systematic surveys in Finland (Finnish National Forest Inventory) (n=546) and the authors’ own fieldwork data in Russia (n=101). On the Finnish side the forest patches are significantly smaller than on the Russian side. In addition, the Finnish forests landscape is more scattered and distances between patches of the same forest type are longer. The Russian side is more dominated by broadleaved and mixed forest stands. The disparities are due to differences in forestry policy and traditions of forest practices. The growing conditions of the areas are similar. The habitat fragmentation and habitat connectivity are important issues because the Karelian Isthmus is one of three main corridors and migrating routes connecting large Russian boreal taiga forests and their fauna and flora with Finnish isolated boreal forests.  相似文献   

13.
The impacts of alternative levels of timber cuttings were evaluated by means of a fixed-price input–output model. The impacts were identified by means of backward linkages of forest-industry's output. The impact on output of consumption linkages in sawmilling outnumbered direct and indirect linkages in pulp and paper manufacturing marginally. Powerful income-generation effects in sawmilling also served to prove the importance of stumpage revenue. Extending sawn goods production created more jobs in all stages of the diffusion process. The discussion on the presumptions applied can assist in further research on the topic.  相似文献   

14.
15.
Ownership is a multidimensional phenomenon that includes legal, social, and emotional aspects. In addition to legal aspects, the social and emotional aspects, “feelings of ownership,” potentially have behavioral effects. Nevertheless, these aspects are often overlooked in the research influencing the forest owners' behavior and thus their forest management decisions. This article examines how private forest owners with inherited forest holdings construct feelings of ownership toward their forests and how these constructions are reflected in their forest management decisions. Forest ownership is addressed through the theory of psychological ownership. On the basis of 15 thematic in-depth interviews, we suggest that a sense of identity and control, as dimensions of psychological ownership, can influence whether forest management decisions are guided by tradition, economic incentives, or responsibility toward property. Based on the results, a forest owner typology (restricted, indifferent, informed, and detached forest owners) was constructed, further enabling us to understand the differences among private forest owners and the roots of their forest management decisions. More generally, the study highlights the important role of emotions in forest management decisions.  相似文献   

16.
Severe storm damage has been a recurring problem to the Swedish forestry sector since, at least, the start of the19th century. This short communication presents a regionally resolved time-series of storm damage in Swedish forests during the last century. Data on storm damage have been gathered from the National Board of Forestry, the Regional Forestry Boards and scientific reports.Storm damage in Swedish forests seems to have increased during the century with a peak around the 1980s. In total 110 million m3 forest were destroyed by 77 recorded wind storms, with the severe storms in 1954 and 1969 accounting for 49% of the total damage. Reported damage in southern Sweden was normalised against the area of productive forest with trees older than 40 years, for inter annual comparisons. The geostrophic wind was used to describe the regional wind direction during the storm events. Most damage occurred during NNW to SW winds, and by winds from NNE. Apart from a possible shift in storm intensity and frequency, the increase in storm damaged trees can be attributed to changes in regeneration and thinning regimes, variations in storm damage reporting system, increase in forest cover and various damage to root architecture.  相似文献   

17.
Dendroecological techniques were used to examine the disturbance history and patterns of species recruitment in an old-growth Quercus rubra L. (northern red oak)–Acer saccharum Marsh. (sugar maple)–Tilia americana L. (basswood) forest on a steep, talus slope in eastern West Virginia. The forest was uneven-aged as were the populations of red oak. Sugar maple dominated the sapling layer, which comprised little or no basswood and red oak. A compilation of major and moderate releases (indicative of disturbance) in 25 cores revealed single or multiple release events in every decade from 1870–1990. The high elevation of the forest coupled with a fertile sub-soil beneath the talus ameliorated the outwardly harsh conditions of the site, allowing for the domination of typically mesophytic, nutrient demanding tree species. We observed several fire scarred trees as well as extensive small-scale blow-down throughout the forest. Frequent disturbance events were probably crucial to the co-existence and continuous canopy recruitment of the relatively light demanding red oak with highly shade tolerant sugar maple and basswood. The strong successional replacement tendencies of red oak by northern hardwoods noted elsewhere in the eastern US may be less apparent on high elevation, rocky sites in the central Appalachians. Thus, this is a unique case study of long-term red oak domination with later successional species in an old-growth forest.  相似文献   

18.
Abstract

Although recreational pressure correlates to population size which in turn influences city growth, there is little evidence of how such processes of urban growth have affected the availability of urban fringe forests (forests with good recreational qualities located completely outside and up to 3 km from the city borders). Hence, the aim of this study was to examine consequences of urban growth on urban fringe forest availability in Sweden for the period 2000–2010. An overlay analysis was conducted in a GIS to identify urban fringe forests with good recreational qualities. A selection of Swedish cities with >2000 inhabitants (n = 428) was used along with a regional division to identify trends of cities in forest regions and in other regions. Results showed that the median availability of urban fringe forests had increased in all regions, both in absolute amounts and per 1000 inhabitants. A majority of the cities individually showed increased levels of urban fringe forests, despite contemporary urban growth. Availability had also decreased in about a third of the cities, most notably among those with greater population growth. Increasing populations and a future demand for recreation in proximate forests make further studies relevant, as other processes than urban growth have affected the availability of urban fringe forests.  相似文献   

19.
IntroductionForestisakindofmulti-function'resourcethatcanbesustaininglyutiIized,butsomeprobIems,suchasinsufficiencyoftimberyieId,soiIerosion,cIimateim-baIanceinpartdistrictetc.,oftenarousedbecauseofincorrectuseandmanagementofnaturalresources.InordertodevelopthefOrestry,IotsoffOrestrypoIi-cieshavebeenissuedandcarriedout.V8rioustypesofforestresourcesmanagementhavebeenaroused,especialIycollectiveforestareasinsouthChina.However,whydiff6rentefficiencies,good,badandworse,eventoresultinthedecrea…  相似文献   

20.
Most traditional studies of mean tree mass (MTM)– density relationships focus on crowded stands, without considering stands characterized with canopy gaps. We developed a model to estimate MTM of closed and unclosed forest stands based on stand density index (SDI). Data were obtained from eight forest stands in China to test the generality of this model. MTM was accurately expressed in terms of SDI by combining the equations for SDI and Yoda's model, and exponents of the MTM–SDI relationship ranged from –2.23 to 1.93. Compared with density, SDI is a better predictor of MTM, regardless of the degree of canopy closure in the stands.  相似文献   

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