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1.
Jerome K. Vanclay 《Small-Scale Forestry》2007,6(2):205-218
It is generally agreed that effective conservation requires the cooperation of private landholders to complement reserve-based
efforts, but there is little agreement about how this can best be achieved. Various stakeholders lobby for tough regulations,
for greater landholder freedom, and for incentives for activities or outcomes. A review of these alternatives suggests an
emerging consensus that incentives are the most effective approach. Policy-makers should consider incentive-based approaches
such as stewardship support to foster conservation outcomes on private lands.
相似文献
Jerome K. VanclayEmail: |
2.
To investigate the household-level economic importance of income from forests under different tenure arrangements, data were collected from 304 stratified randomly sampled households within 10 villages with community forest user groups in Tanahun District, Western Nepal. We observed that forest income contributed 5.8% to total household income, ranging from 3.8% in the top income quartile to 17.4% in the lowest quartile. Analyses of poverty indices and Gini decomposition showed that incorporating forest incomes in total household income reduces measured rural poverty and income inequality. Community forestry income constituted 49.7% of forest income, followed by 27.5% from government-managed forest, and 22.8% from private forests/trees. Community forestry income, however, contributed more than other sources of forest income to income inequality, indicating elite capture. We argue that a full realisation of community forestry's poverty reduction and income equalizing potential requires modifications of rules that govern forest extraction and pricing at community forest user group level. 相似文献
3.
This study considers a carbon tax system as a policy tool for encouraging carbon sequestration through modification of management in existing forests and examines its welfare impacts and costs of the carbon sequestered. The simulated carbon tax leads to reduced harvest and increased carbon stock in the standing trees and understory biomass. Changes in the level of silvicultural investments vary by owner, depending on the nature of their initial inventory. In general investment under the tax is concentrated in regimes that establish faster growing plantations. Average rotation age increases, varying in extent across ownerships and site qualities. The carbon tax reduces both consumer and producer surpluses in regional timber markets. Producers are compensated by the carbon subsidies, except at low carbon tax levels. Not all rates of carbon tax will attract interest from private owners if participation is voluntary. Estimates of the marginal cost of sequestering carbon in western Oregon private forests are shown to be within the range of costs for projects considering afforestation alone in some eastern regions of the United States. 相似文献
4.
Takuya Hiroshima 《Journal of Forest Research》2007,12(6):417-424
The Gentan probability is defined as the probability that a newly planted forest stand will be harvested at a certain age.
In this study, the Gentan probability was estimated using the price of logs, in accordance with the notion that the probability
is influenced by economic factors. In order to estimate the Gentan probability, we adopted a probability density function
based on the forest owners’ decision-making process, which consisted of a decision criterion, a decision criterion function
and a criterion threshold. The price of logs was employed for the criterion, and the decision criterion function was defined
as the value of the forest stand based on the price of logs. Moreover, the mechanism of changes in the threshold was formulated
based on the random walk concept. The parameters of the suggested Gentan probability were calibrated to fit the harvesting
tendencies observed in the past. Finally, the Gentan probability distributions estimated using the prices of logs over the
past 20 years were compared with those estimated using felling age means and variances. The two distributions were closely
correlated during most years. The proposed Gentan probability model takes advantage of short-term yield predictions such as
an analysis of forest owners’ reactions to the current price changes. 相似文献
5.
Liina Häyrinen Osmo Mattila Markus Närhi Anne Toppinen 《Scandinavian Journal of Forest Research》2017,32(4):327-337
The transformation of the forest sector toward a bioeconomy calls for finding new sources of competitive advantage for the whole sector to retain its future viability. Non-industrial private forest owners are an important group of actors in the Finnish forest-based sector, as they supply 80% of industrial roundwood and control numerous other tangible and intangible forest-based ecosystem services. Our study analyzes forest owner views on the future use of forests in Finland, their perceptions on the evolving sectorial interlinkages and the position of the forest sector now and in the future bioeconomy. The data were collected in two phases: through telephone interviews of forest owners (n?=?278) and four focus group (FG) discussions (n?=?17), and were analyzed both qualitatively and quantitatively. The interviews showed that forest owners consider the highest potential for strengthening the sector toward bioeconomy to come from collaboration with energy and construction businesses. During the FG phase, we identified new possibilities founded on forest-based recreational services, cooperation with nature-based tourism and in increasing value-added wood products. In total, forest owners as a high-involvement group emphasized future value creation to be based upon forest ecosystem services and in diversifying the utilization of forests beyond the dominant raw material-driven mindset. 相似文献
6.
There is increasing worldwide interest in land-use allocation and management within the sphere of rural planning and development. The study of land-use patterns mainly focuses on understanding the practices and values of individuals involved, and no debate of this issue would be complete without taking into account non-industrial private forest (NIPF) ownership as a key component in most rural areas worldwide. This paper empirically explores and assesses NIPF owners' management in terms of analysing dynamics in farming and forestry practices (past conversions from forestland to meadow and from marginal meadow to woodland, and intentions to change the current productive forest species and to extend the area of woodland) and landholding attributes (size and degree of parcellation in productive forestland). Logistic regression models were also used to investigate the probabilities and influencing factors involved in transforming marginal meadows to woodland, and attempts on the part of NIPF owners to change the current productive forest species and increase productive forestland. For this, a total of 103 NIPF owners in Northern Spain were interviewed in person, in March 2004, about their commitment to and involvement in land management during 1999–2003. The models correctly explained 73.3%, 83.7% and 73.3% of the variability in having converted marginal meadow in woodland and of future intentions to change the productive forest species and increase the area of productive forestland, respectively. The results of the study indicate that forest management mainly responds to investment and increasing the productivity of the land as a capital asset, which is directly influenced by the size and degree of parcellation of the holding, and directly or indirectly related to the owner's interest in timber production. The results may be used by forest professionals, researchers and policymakers in order to design and execute successful forest policies related to land management and planning. 相似文献
7.
The purpose of this study was to predict the likely amounts of carbon sequestration on a national scale for Japan in the Article-3.4
private planted forests of the Kyoto Protocol during the first commitment period. We regarded the planted forests that had
undergone silvicultural practices such as weeding, pruning, and thinning since 1990 as Article-3.4 planted forests in accordance
with the definition given by the Forestry Agency of Japan. Regression models were developed to predict the forest areas that
had undergone silvicultural practices, employing silvicultural subsidies and forest workers' wages as predictor variables.
Then the time series changes in the predictor variables were provided by extending their recent trends, with the result being
that the forest areas that have undergone silvicultural practices were predicted on the basis of the three scenarios of the
variables. Thus, the Article-3.4 forest area was calculated considering overlaps of silvicultural practices over fixed stands,
and the area was converted into the amount of carbon sequestration by multiplying it by coefficients such as a volume table,
biomass expansion factor, and others. The result implied that Article-3.4 private planted forests were expected to sequester
8.16–8.87 Mt-C year−1 during the first commitment period. These amounts cover 63%–68% of the carbon sequestration goal by land-use change and forestry
activities capped under the Marrakesh Accords. To realize this prediction, it is important to provide a sufficient silvicultural
subsidy to last until the end of the first commitment period and to implement silvicultural practices on the forest stands
that have not undergone such practices since 1990. 相似文献
8.
《Forest Ecosystems》2015,(2)
Background: Forests are fundamental in maintaining water supplies, providing economic goods, mitigating climate change, and maintaining biodiversity, thus providing many of the world's poorest with income, food and medicine.Too often, forested lands are treated as wastelands or free and are easily cleared for agricultural and infrastructure expansion.Methods: In this paper, the sustainability of two forest ecosystems(state and community/private owned) was evaluated using SPOT-5 satellite images of 2005 and 2011. This study was conducted in a sub-watershed area covering 468 km2, of which 201 km2 is managed by the state and 267 km2 by community/private ownership in the Murree Galliat region of Punjab Province of Pakistan. A participatory approach was adopted for the delineation and demarcation of forest boundaries. The Geographic Object-Based Image Analysis(GEOBIA) technique was used for identification and mapping of ten Land Cover(LC) features.Results: The results show that between the years 2005 to 2011, a total of 55 km2(24 km2 in state-owned forest and 31km2 in community/private forest) was converted from forest to non-forest. The conclusion is that conservation is more effective in state-owned forests than in the community/private forests.Conclusions: These findings may help to mobilize community awareness and identify effective initiatives for improved management of community/private forest land for other regions of Pakistan. 相似文献
9.
Naeem Shahzad Urooj Saeed Hammad Gilani Sajid Rashid Ahmad Irfan Ashraf Syed Muhammad Irteza 《中国林学(英文版)》2015,(2):155-167
Background: Forests are fundamental in maintaining water supplies, providing economic goods, mitigating climate change, and maintaining biodiversity, thus providing many of the world’s poorest with income, food and medicine.Too often, forested lands are treated as "wastelands" or "free" and are easily cleared for agricultural and infrastructure expansion.Methods: In this paper, the sustainability of two forest ecosystems(state and community/private owned) was evaluated using SPOT-5 satellite images of 2005 and 2011. This study was conducted in a sub-watershed area covering 468 km2, of which 201 km2 is managed by the state and 267 km2 by community/private ownership in the Murree Galliat region of Punjab Province of Pakistan. A participatory approach was adopted for the delineation and demarcation of forest boundaries. The Geographic Object-Based Image Analysis(GEOBIA) technique was used for identification and mapping of ten Land Cover(LC) features.Results: The results show that between the years 2005 to 2011, a total of 55 km2(24 km2 in state-owned forest and 31km2 in community/private forest) was converted from forest to non-forest. The conclusion is that conservation is more effective in state-owned forests than in the community/private forests.Conclusions: These findings may help to mobilize community awareness and identify effective initiatives for improved management of community/private forest land for other regions of Pakistan. 相似文献
10.
Topographic and biotic regulation of aboveground carbon storage in subtropical broad-leaved forests of Taiwan 总被引:2,自引:0,他引:2
Ryan W. McEwanYi-Ching Lin I-Fang SunChang-Fu Hsieh Sheng-Hsin SuLi-Wan Chang Guo-Zhang Michael SongHsiang-Hua Wang Jeen-Lian HwongKuo-Chuan Lin Kuoh-Cheng YangJyh-Min Chiang 《Forest Ecology and Management》2011,262(9):1817-1825
There is a growing need to understand, and ultimately manage, carbon storage by forest ecosystems. Broad-leaved evergreen forests of Taiwan provide an outstanding opportunity to examine factors that regulate ecosystem carbon storage. We utilized data from three Taiwan Forest Dynamics Plots (FS, LHC, and PTY) in which every tree is identified, measured, tagged and mapped, to examine factors regulating carbon storage as estimated from aboveground biomass. Allometric equations were used to estimate the aboveground biomass of each tree, and a model building procedure was used to examine relationships between plot-level aboveground biomass (AGB; Mg/ha) and a suite of topographic and biotic factors. We found that our study sites have AGB values comparable to some of the most carbon dense forests in the world. Across all three sites, maximum biomass was contained in the taxonomic families Fagaceae, Lauraceae and Theaceae. In the FS site, we identified slope convexity (P = 0.03) and elevation (P < 0.001) as topographic predictors of AGB and found that maximum AGB was found in topographically flat areas. In FS, stem density (P < 0.001) was a significant biotic predictor of AGB and the maxima occurred at intermediate densities. In LHC, we found that convexity (P < 0.001) and slope (P < 0.001) were significantly related to AGB which was maximized along a topographic ridge in the plot. Species richness (P < 0.001) was a significant biotic predictor of AGB in LHC, and the relationship indicated slightly higher AGB at higher levels of species richness. The only significant factor related to AGB in PTY was species richness (P = 0.02). Further work is needed to seek a mechanistic understanding of topographic factors and species richness as drivers of carbon storage in forests. 相似文献
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《Forest Ecology and Management》2006,236(1):12-17
Ivy (Hedera helix L.) favours moist nutrient-rich substrates of the floodplains of Western Europe. In this study we investigated ivy dynamics in two forest reserves of the upper Rhine. The aim was to determine the influence of flooding on ivy development following the cessation of cuttings at two forest sites of contrasting flooding regimes: the Rhinau Reserve is currently flooded while the Erstein site has not been flooded for 30 years. We also examined the impacts of severe storms in 1993 and 1999 and a long-lasting flood that occurred in 1999.Our results show that the population of Rhinau was smaller and younger because ivy is severely limited by long periods of anoxia, even though it is favoured by regular short-period floods. Indeed, juvenile growth was more rapid at Rhinau where nutrient and moist conditions are more favourable than in Erstein, but mortality was higher because of the long-lasting flood of 1999. At Erstein, the ivy showed a tendency to clump around several big trees, especially oaks and ashes, which may make the host tree vulnerable to windfall. Uprooted or broken ivies were found to survive better than the fallen host tree but could not climb to another trunk highlighting a strong dependence of ivy on its hosting tree. 相似文献
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A combination of superior wood quality and high productivity has made Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) one of the premier timber trees in the world. As such, it is grown as a plantation species in several countries in Europe, South America, New Zealand, and Australia, as well as throughout its extensive natural range in western North America. Decades of experience with the silviculture of young stands have demonstrated that practices such as planting, the use of genetically improved seedlings, precommercial and commercial thinning, and fertilization may dramatically increase the yield of industrial products over that of natural forests. Further, such silviculture is compatible with the production of desired amenities. Vigorous implementation of such practices wherever Douglas-fir is cultivated will increase the world's timber resources, and be an effective strategy for reducing the pressure, occasioned by the world's rapidly increasing population, to harvest the fragile tropical and boreal forests. 相似文献
16.
Forest buffer zones have recently been introduced in an attempt to suppress debris movement caused by mass wasting. There
are, however, many questions left unsolved regarding the role of forests in suppressing debris movement and damage to forests
by debris deposition. A number of debris avalanches occurred in southern Fukushima Prefecture and Hiroshima Prefecture in
August 1998 and June 1999, respectively. Suppression of debris movement by forests and damage to forests by debris deposition
were investigated in this study using aerial photographic interpretation and topographic analysis. Of the debris avalanches
delineated in the Fukushima and Hiroshima areas, 282 and 84 sites, respectively, were forested, and 43 and seven sites, respectively,
were nonforested. Topographic parameters, land use, and forest type at each site were surveyed by aerial photographic interpretation
and topographic analysis. Suppression of debris movement by forest vegetation was confirmed by higher equivalent coefficients
of friction and shorter average deposition zone length (about 28% and 55% shorter in the Fukushima and Hiroshima areas, respectively)
in forested sites compared with nonforested sites. While previous studies suggested that the width of the forest zone required
to prevent sediment outflow by surface erosion increases with increasing slope gradient, no clear relationship was found in
this study. While the length of deposition zone of debris material (this study) is strongly affected by the dynamic solid
friction coefficient and fluid friction of debris material, the length of deposition zone of the outflow of surface wash (past
studies) is mainly affected by the tractive force of water flow. Among the 65 trees that remained at the terminus of deposition
zones at five sites, 36 were alive and 29 were dead. Damage to the forest increases with increasing thickness of deposits
and decreases with increasing tree diameter. Such results are useful for designing forest buffer zones.
Received: June 18, 2001 / Accepted: August 21, 2002
Correspondence to:Y. Ishikawa 相似文献
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Poplars (Populus spp.) have been planted in Europe and Asia since very early times. Known in the Near East as the blessed tree, poplars have been the primary timber producer in regions lacking natural forests in the northern hemisphere. Now, though, we are seeing poplar plantations becoming part of the forest resources even in the abundantly forested Pacific Northwest. Though still a minor contributor to the world's timber supply, the area of land planted to poplars is, nevertheless, increasing rapidly, particularly in China, South Korea, and the United States. The 1992 report from the International Poplar Commission listed nineteen countries with at least 10,000 ha of planted poplars and seven with more than 100,000 ha. Much of the success of poplar plantations results from the breeding of fast-growing and disease-resistant poplar hybrids. Accordingly, at least eleven countries support poplar breeding programs. Uses of poplar wood range from peeled poles for rafters and other elements of construction in agrarian economies to the manufacture of paper, plywood, oriented strand board, and engineered lumber in industrial nations. Interest has also developed in poplar plantations as a renewable source of energy. 相似文献
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Emerging forests on abandoned land: Puerto Rico’s new forests 总被引:1,自引:0,他引:1
The species composition of forests change continuously as the earth’s biota evolves and adjusts to environmental change. Humans are accelerating the rate of species turnover by moving species around the planet and dramatically changing environmental conditions. Our focus is on new forests in Puerto Rico that emerge naturally on abandoned lands previously converted to agriculture and degraded. These forest stands have combinations of species that are new to the island’s landscapes. New forests exhibit high species dominance during forest establishment, which includes dominance by alien tree species. These alien tree species establish and maintain forest cover, which may facilitate regeneration of native tree species. Landscape analysis and literature review revealed that these emerging stands are highly fragmented (60% were <1 ha in 1991), function as refugia for native organisms, and at 60–80 years old have similar species richness and structural features as native stands of similar age. However, the island’s new forests exhibit important differences from mature native forests on unconverted forestlands. New forests have fewer endemic species and fewer large trees (≥55 cm dbh) than mature native forests; they have higher soil bulk density and lower soil carbon and litter stocks; and they accumulate aboveground biomass, basal area, and soil carbon more slowly than native forests of similar age. We suggest that new forests will become increasingly prevalent in the biosphere in response to novel environmental conditions introduced to the planet by humans. 相似文献