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1.
Ayalneh Bogale 《Journal of Sustainable Forestry》2013,32(6):518-542
This research employs a contingent valuation method (CVM) to estimate the respondents' willingness to pay (WTP) to gain use and control rights to a natural forest resource at the Adaba-Dodola Forest Priority Area (ADFPA) in the Bale Mountains of Ethiopia. The analysis was based on data collected from 295 households residing in and around the forest resource. Both binary probit and ordered probit models were used to examine socioeconomic factors that determine the respondents' WTP to gain these rights. The estimated mean and median WTP were found to be ETB 24.41 (US$2.54) and ETB 22.14 (US$2.30) annually, respectively. Households with more members, have better exposure to education and training, perceive the need for forest conservation, are member of forest dwellers' association, and who are wealthier in terms of ownership of more cultivated land and livestock are willing to pay more; whereas those households characterized by earning better annual household income, those who got higher starting bid value, and those who live farther away from the prime forest resource are willing to pay less. This can be used to signal that there is a considerable non-market value attached to use and control rights to the natural forest. In particular, membership in official forest user groups has shown a strong and positive relationship with WTP in all the models employed. This implies the approach of participatory management using forest user groups is better both for the sustainability of the forest resource and the livelihoods of the people who depend upon it. 相似文献
2.
《Southern Forests》2013,75(3-4):201-206
The different interests in forest resources by various stakeholders may result in differences in perceived value of forest conservation. In order to test this hypothesis, we compared the valuation by international ecotourists and local respondents of the perceived benefits of the Mabira Central Forest Reserve. The factors that influenced respondents’ valuation of forest conservation were also investigated. Describing a hypothetical scenario to elicit respondents’ willingness-to-pay (WTP) for forest conservation was the central part of the questionnaire. The WTP;income ratio was used to estimate respondents’ perceived value of forest conservation. A chi-square (χ 2) test indicated significant association between respondent category (local and tourist) and categories of perceived benefits (p-value = 0.001). The locals were more interested in direct-use values while the tourists showed greater interest in the indirect-use values. A Student's t-test showed that the WTP:income ratios of the locals were much higher than for the ecotourists (p-value < 0.001). This implies that the local communities had a higher valuation of forest conservation than the ecotourists. Regression analysis revealed that all other factors being constant, the WTP of respondents who perceived direct- and indirect-use value as the most important forest benefit was significantly higher (p < 0.05) than those who perceived no value by $5.8693 and $0.02628, respectively. The respondents who rated the contribution of the ecotourism project to community development as moderate had a significantly higher WTP compared to those who rated it as low by $6.6908. Overall, these results indicate that the benefits people derive from the forest either through direct or indirect uses influence valuation of forest conservation. Results also indicate that although ecotourismrelated benefits improved attitudes towards forest conservation, ecotourism alone may not be an adequate conservation tool because of the limited support it can provide to the local community. 相似文献
3.
Non-industrial private forests (NIPFs) and public forests in the United States generate many non-market benefits for landholders
and society generally. These values can be both enhanced and diminished by wildfire management. This paper considers the challenges
of supporting economically efficient allocation of wildfire suppression resources in a social cost-benefit analysis framework
when non-market values are important. These challenges include substantial gaps in scientific understanding about how the
spatial and temporal provision of non-market values are affected by wildfire, the limited utility of benefit transfer in wildfire
assessment, a lack of studies that have estimated marginal willingness-to-pay to conserve non-market values, violation of
consumer budget constraints, and the infeasibility of valuing indigenous cultural heritage. These challenges present serious
impediments to adapting price-based decision-support tools to accommodate non-market values and support decision-making consistent
with contemporary federal wildfire policy. Departure from the historic range and variability of ecological conditions is proposed
as a complementary framework to support wildfire management decisions when non-market values are important on NIPF and public
forestland.
相似文献
| Tyron J. VennEmail: |
4.
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
5.
Understanding the changes occurring within the forestry sector is complicated by socio-economic and demographic changes within
rural communities - sometimes in areas where commercial forestry has a long tradition. These changes in some rural communities,
particularly coastal New South Wales, appear significant for forestry because land ownership and management are increasingly
disconnected from the traditional agricultural land use. There is an increasing population of landowners in ‘lifestyle’ landscapes
who do not appear primarily driven by maximising the profitability of farming. The shift from ‘production’ to ‘lifestyle’
landscapes also reflects a transition in community expectations for forestry - a profound change that is likely to require
quite different approaches to management. Landholders may be more likely to be interested in forestry with multiple values,
including both timber products and environmental services. Furthermore, well-managed native forests that are integrated into
individual properties and wider landscapes, may increase the market value of the property, representing a prudent business
investment. This paper presents a method for analysing the relationship between rural land values and the estimated agricultural
value of typical farms in a number of localities in New South Wales, as a means of interpreting the underlying social values
of landholders. It is argued that such analysis can be helpful in identifying changes in community values as a signal that
approaches to private native forestry may also need to change to accommodate the aspirations of ‘lifestyle’ landholders, who
may value the aesthetics of native forests more highly than timber production. 相似文献
6.
Investigating agroforestry systems that incorporate poultry is warranted in Northern Europe as they may offer benefits including: improved welfare and use of range; reduced feed costs; price premia on products; reduced payback periods for forests; and, greater returns on investment. Free-range egg production accounts for 27% of the United Kingdom egg market and demand for outdoor broilers is increasing. No research has been conducted recently on the economic viability of agroforestry systems with poultry. An economic model was constructed to: assess economic viability of a broiler agroforestry system; and, investigate the sensitivity of economic performance to key factors and interactions, and identify those which warrant attention in research and management. The system modelled is a commercial trial established in Southern England in 2002 where deciduous trees were planted and broilers reared in six- or nine-week periods. The model uses Monte Carlo simulation and financial performance analyses run for a 120-year period. An Internal Rate of Return (IRR) of 15.5% is predicted for the six-week system which remains viable under a ‘worst case’ scenario (IRR of 12.6%). Factors which affect financial performance most (decreasing in magnitude) are prices achieved for broilers, costs of brooding houses, chicks, arks, feed and timber prices. The main anticipated effects of biological interactions on financial performance (increased ranging on feed conversion and excess nutrient supply on tree health) were not supported by analysis. Further research is particularly warranted on the welfare benefits offered by the tree component and its relation to price premia. 相似文献
7.
采用条件价值法,通过调查消费者的支付意愿,研究了扎龙湿地的非使用价值.扎龙湿地的非使用价值为49.34亿元·a-1,其中存在价值为30.19亿元·a-1,遗产价值为13.62亿元·a-1,选择价值为5.53亿元·a-1,扎龙湿地人均支付意愿值(WTP)为40元·a-1;职业、文人程度、了解程度、偏爱程度与支付意愿呈极显著相关关系;性别、技术职称、收入水平与支付意愿不相关.年龄、职业、了解程度、偏爱程度与WTP值均极显著相关;性别与WTP值显著相关,而与技术职称、收入水平不相关. 相似文献
8.
The relationship between number of species and area observed has been described using numerous approaches and has been discussed
for more than a century. The general objectives of our study were fourfold: (1) to evaluate the behaviour of species–area
curves across geographic scales, (2) to determine sample sizes necessary to produce acceptably precise estimates of tree species
diversity, (3) to evaluate relationships among estimates of tree species diversity for local to large geographic scales, and
(4) to determine whether the proportion of native tree species may be precisely estimated using sample sizes smaller than
those necessary to estimate total tree species diversity. Such investigations are necessary to improve biodiversity monitoring
at large scales. The analytical approaches included Monte Carlo bootstrap simulations and two geospatial methods and relied
on a database populated with data for more than 12,000 national forest inventory plots (NFI) from 16 regional units, 13 European
countries and three ecoprovinces of the United States of America (USA). Four primary results were obtained. First, tree species
diversity may be precisely estimated using observations for a random subsample of 2,000–4,000 NFI plots. Second, large sample
sizes are necessary to estimate tree species diversity for regional units or forest categories, except possibly for boreal
forests for which the number of tree species is small. Third, estimates of the proportion of native tree species may be precisely
estimated using tree species information for a random sample of approximately 30 NFI plots. Finally, our estimated species–area
curves show that the curve shapes and relationships among estimates of tree species diversity at large scales clearly depend
on the relative geographic location of the anchor regional unit (a European country or ecoprovince of the USA) relative to
the other regional units. None of the well-known models for species–area curves adequately describes our results. The conclusion
was that the uncertainties of the estimates reflect the unfavourable state of global biodiversity monitoring of species groups.
The total numbers of tree species in our regional units, which cannot be adequately estimated, are small relative to other
tree species-rich regions. Consequently, monitoring of tree species diversity is currently a highly uncertain enterprise at
large scales. 相似文献
9.
The paper describes the results of a postal questionnaire surveyinto the extent of oak ‘shake’ in Great Britain.On average, 21 per cent of all oak was degraded by some formof shake. On a national scale, this represents a reduction inpotential harvesting revenues to growers of between £3million and £8 million annually, and larger sums if thecost of replacement imported hardwoods is considered. 相似文献
10.
A group of scientists conducted a comprehensive investigation on ecological safety and water and soil erosion in the Northwest
Loess Plateau, Northwest China. The data gathered was analyzed in terms of achievement, existing problems, and strategy and
measures on vegetation restoration in the area. Since the policies of conversion from cropland to forest (CCF) and forbid
grazing and cutting (FGC) were carried out, vegetation quality and coverage rate increased quickly in the Loess Plateau area,
strengthening the concept of eco-environment protection. Environment harness measurements were optimized. The multiform investments
on eco-environment and urbanization development in China will benefit vegetation restoration. However, there have been some
persisting problems, such as the shortage of investment, instability of government policy, expectation of extravagant economic
benefit, larger rate of plantation, and scarce technologies supporting vegetation restoration. Many key theories and practice
problems require an urgent resolution. In the future, short-, mid-, and long-term goals for vegetation restoration should
be clear, achievement should be expanded, and the natural restoration area should be increased. The benefit for the contractor
on vegetation restoration should be ensured. Investment on vegetation building research work should be increased.
__________
Translated from Scientia Silvae Sinicae, 2007, 43(1): 102–106 [译自: 林业科学] 相似文献
11.
Eva J. Garen Kristin Saltonstall Jacob L. Slusser Shane Mathias Mark S. Ashton Jefferson S. Hall 《Agroforestry Systems》2009,76(1):219-236
In the Republic of Panama, reforestation with native species is of great interest, but many landholders often do not participate
in tree planting projects and little information exists about landholder interest in, or experiences with, native trees. This
study evaluates the experiences of farmers participating in a native species reforestation initiative in rural Panama to identify
lessons learned that can guide on-going or future tree planting efforts. Based on the results of a questionnaire administered
to program participants and non-participants (n = 68), we found that trees are important to farmers for multiple reasons, primary a variety of environmental and economic
benefits. No relationship between the size of landholdings or land tenure status and the desire to plant trees was found.
All participants in the program considered their experience to be positive, few had problems with their plantations, and most
were interested in planting more native trees. The program’s frequent and ongoing technical support was an important factor
for farmers. These results indicate widespread interest in, and success with, planting native species and underscore the need
to systematically examine farmers’ interests and perceptions when planning, implementing, and evaluating reforestation initiatives. 相似文献
12.
Outdoor recreation encompasses an array of activities carried out in a multitude of envrionments, including forests. An important motive for participating is the possible mental and physical health benefits gained. Currently, there is an absence of studies which have examined the economic aspects of the health effects from outdoor recreation. The main aim of this study was to use the contingent valuation method to compare the willingness to pay (WTP) for avoiding a hypothetical suspension of outdoor recreation among forest recreationists and hunters in Sweden. The second aim was to analyze the determinants of this WTP change, with emphasis on perceived health states obtained by means of a visual analogue scale. The results showed that changes in health state due to participation as well as visiting frequency were significant predictors of WTP. These findings suggest that health state measures may be useful for assessing health outcomes of outdoor recreation and associated WTP. 相似文献
13.
Carly Green Brian Tobin Michael O’Shea Edward P. Farrell Kenneth A. Byrne 《European Journal of Forest Research》2007,126(2):179-188
Reporting carbon (C) stocks in tree biomass (above- and belowground) to the United Nations Framework Convention on Climate
Change (UNFCCC) should be transparent and verifiable. The development of nationally specific data is considered ‘good practice’
to assist in meeting these reporting requirements. From this study, biomass functions were developed for estimating above-
and belowground C stock in a 19-year-old stand of Sitka spruce (Picea sitchensis (Bong) Carr.). Our estimates were then tested against current default values used for reporting in Ireland and literature
equations. Ten trees were destructively sampled to develop aboveground and tree component biomass equations. The roots were
excavated and a root:shoot (R) ratio developed to estimate belowground biomass. Application of the total aboveground biomass function yielded a C stock
estimate for the stand of 74 tonnes C ha−1, with an uncertainty of 7%. The R ratio was determined to be 0.23, with an uncertainty of 10%. The C stock estimate of the belowground biomass component was
then calculated to be 17 tonnes C ha−1, with an uncertainty of 12%. The equivalent C stock estimate from the biomass expansion factor (BEF) method, applying Ireland’s
currently reported default values for BEF (inclusive of belowground biomass), wood density and C concentration and methods
for estimating volume, was found to be 60 tonnes C ha−1, with an uncertainty of 26%. We found that volume tables, currently used for determining merchantable timber volume in Irish
forestry conditions, underestimated volume since they did not extend to the yield of the forest under investigation. Mean
stock values for belowground biomass compared well with that generated using published models. 相似文献
14.
Black walnut (Juglans nigra) is a prime tree species for agroforestry practices in the United States providing highly prized wood and nuts for human
consumption and wildlife. In 54 black walnut stands in south central United States, the site index (i.e., mean dominant height
[DH], at age 25 years) ranged between 5.2 and 21.4 m, and was independent of stand density. There were no differences in height
and stem diameter (DBH) growth rates between stands with improved varieties and native stock. Most stands were in a “free
growth” stage because of either early age or wide spacing. Mean annual increments in DBH and height were positively related
both for improved varieties and native stock. Understory competition had a substantial detrimental effect on DH. In a 26 year-old
stand, trees growing within Kentucky blue grass (Poa pratensis) had a site index 5 m greater than trees growing within tall fescue (Festuca arundinacea). Predicted nut yields in 2002 varied between 0 and 1370 kg of hulled nuts per ha. Improved varieties had, in general, higher
nut yields than predicted from a nut yield-DBH equation developed for individual trees. Nut yields were highly variable both
within and among stands, and were related to DBH in native stock but not in improved varieties. 相似文献
15.
David Thompson 《Small-Scale Forestry》2007,6(2):157-175
With large areas of public native forests now converted into National Parks and unavailable for timber harvest, private native
forests (PNF) in New South Wales (NSW) are becoming increasingly important in providing timber for the wood processing industry.
At the same time, there is increasing interest in the role that these private forests play in providing and maintaining habitat
for wildlife. Historically, timber production from these forests has been opportunistic, with little or no silviculture to
maintain wood production potential. Market circumstances and policy settings have not favoured sound silvicultural practice,
generating an exploitative and short-term view of the timber resource to maximise short-term returns. This has occurred at
a time when these forests are an important and increasing source of log supply to industry. This paper discusses payment of
biodiversity credits (incentives) to improve both environmental management and timber production outcomes, and examines the
findings of some recent studies on the ‘sustainability’ of PNF. Willingness-to-pay (WTP) and willingness-to-supply studies
reveal a disparity between the demand and supply prices for biodiversity and habitat ‘services’ in many cases. Recent ‘sustainability’
studies indicate forestry operations are relatively benign in their impacts on biodiversity, compared to other land uses.
However, in the absence of increased financial returns from PNF and in the face of increased public demand for greater environmental
outcomes, there seems little alternative to meeting the competing demands of biodiversity and timber production than to implement
a system of incentive payments which reward sound private forest management for a multiplicity of objectives.
相似文献
| David ThompsonEmail: |
16.
Jiangming MA Shirong Liu Zuomin Shi Yuandong Zhang Bing Kang Baoyu Chen 《Frontiers of Forestry in China》2008,3(3):300-307
By adopting the concept of space as a substitute for time, we analyzed the dynamics of species composition and diversity of
different restoration sequences (20, 30, 40, 50 years) in two secondary forest types in western Sichuan Province, distributed
in a northerly or northwesterly direction. The analysis was based on the results of measurements of 50 plots located at elevations
between 3100–3600 m. The forests originated from natural regeneration in combination with reforestation of spruce when the
old-growth bamboo-dark brown coniferous forests and moss-dark brown coniferous old growth forests were harvested. Similar
old-growth dark brown coniferous forests at ages ranging between 160 and 200 years were selected as the reference forests
for comparisons. We recorded 167 species of vascular plants from 44 families and 117 genera. There was no significant difference
in terms of the number of species among secondary forests. But the importance values of dominant species varied during the
restoration processes. The dominant species in the secondary forests is Betula albo-sinensis, while Abies faxoniana is the dominant species in old-growth dark brown coniferous forests. Species richness increased significantly with restoration
processes. It increased quickly in secondary forests during the period from 30 to 40 years, but decreased significantly in
the old-growth dark brown coniferous forests. The species richness among growth forms decreased in the following order: herb
layer > shrub layer > tree layer. The maximum value of the evenness index occurred in secondary forests at age 40 and remained
relatively stable in the bamboo-birch forests, but the evenness index tended to decrease in moss-birch forests and slightly
increased in the old-growth mossdark brown coniferous forests. There was a statistically significant difference in the eveness
index between the tree and shrub layers as well as between the tree layer and the herb layer, but there was no significant
difference between the shrub layer and the herb layer. The value of the Shannon index increased over restoration time. In
bamboo-birch forests, the maximum value of the Shannon index was 3.80, recorded at age 50. In moss-birch forests, the maximal
value was 3.65, reached in this forest at age 30. The value of the Shannon index of old-growth dark brown coniferous forests
was recorded between younger secondary and older secondary forests. The value of the dominance index of communities varied.
At the first stage of restoration, it increased, and at the end it was decreased. The dominance index of the tree layer had
a similar trend as that of the community dominance index, but was more variable. The minimum value of the dominance index
of the tree layer in the moss-birch forests reached 20 years earlier than that of the bamboo-birch forests. There was a significant
difference among restoration sequences in the α diversity indices except for the dominance index. No significant differences
between the two secondary forest types were detected. Over age, the value of the Bray-Curtis index between secondary forest
and old-growth dark brown coniferous forest increased.
__________
Translated from Scientia Silvae Sinicae, 2007, 43(5): 17–23 [译自: 林业科学] 相似文献
17.
Sandra Eckert Harifidy Rakoto Ratsimba Lovanirina Olivia RakotondrasoaLalanirina Gabrielle Rajoelison Albrecht Ehrensperger 《Forest Ecology and Management》2011,262(11):1996-2007
Madagascar is currently developing a policy and strategies to enhance the sustainable management of its natural resources, encouraged by United Nations Framework Convention on Climate Change (UNFCCC) and REDD. To set up a sustainable financing scheme methodologies have to be provided that estimate, prevent and mitigate leakage, develop national and regional baselines, and estimate carbon benefits. With this research study this challenge was tried to be addressed by analysing a lowland rainforest in the Analanjirofo region in the district of Soanierana Ivongo, North East of Madagascar. For two distinguished forest degradation stages: “low degraded forest” and “degraded forest” aboveground biomass and carbon stock was assessed. The corresponding rates of carbon within those two classes were calculated and linked to a multi-temporal set of SPOT satellite data acquired in 1991, 2004 and 2009. Deforestation and particularly degradation and the related carbon stock developments were analysed. With the assessed data for the 3 years 1991, 2004 and 2009 it was possible to model a baseline and to develop a forest prediction for 2020 for Analanjirofo region in the district of Soanierana Ivongo. These results, developed applying robust methods, may provide important spatial information regarding the priorities in planning and implementation of future REDD+ activities in the area. 相似文献
18.
In the Zona da Mata of Minas Gerais State, Brazil, family farmers are adjusting to agroecological principles to reconcile
sustainable agriculture, livelihood improvements and biodiversity conservation. Starting in 1993, experimentation with coffee
agroforestry was gradually initiated on an increasing number of farms (37 in total), resulting in the simultaneous management
of sun coffee (SC) and agroforestry coffee (AF) plots. We aimed (1) to identify factors that determine the farmers’ selection
of trees used in AF; (2) to describe the agroecological farms in transition; and (3) to perform an economic comparison between
AF and SC. These objectives were addressed by combining data from botanical surveys in 1993/1994 and 2007, by interviews with
farmers and by detailed data on the production value and costs of labour and material inputs. The results showed considerable
diversity in farming strategies and management among the farmers. Early adopters of AF had diversified towards production
of different marketable products. The use of native trees in AF for this purpose, and for restoration of soil fertility (e.g.,
leguminous trees), had increased since the start of the experiments, while exotic tree species were eliminated. Over a period
of 12 years AF was more profitable than SC due to the production of a diversity of agricultural goods, despite somewhat higher
establishment costs. Other ecosystem services delivered by AF, such as biodiversity and cultural services are currently not
valorized. Payment schemes for environmental services could further improve the economic benefits of AF for family farmers
and alleviate establishment and learning costs. 相似文献
19.
珠江三角洲陶瓷工业污染区植被受害证据与启示 总被引：8，自引：0，他引：8
以长期暴露在大气污染胁迫下的村边林为对象,进行植物群落结构调查、植物受害分析,探讨了陶瓷工业污染排放对植被的影响。调查样地位于广东南海区五星村边坡地的半自然次生林内,乔木层和灌木、草本幼苗层的调查分别在10个10m×10m和4个5m×5m的样方内进行。该森林群落以隆缘桉和尾叶桉数量占优势,其次是乡土树种鸭脚木、泥竹,重要值依次为26.75、17.08、16.27和11.50。隆缘桉和马尾松冠层枝叶完全枯死、脱落,受害程度达100%;其次是泥竹和南岭黄檀受害程度分别为85.1%和68.3%。尾叶桉、朴树、越南山龙眼、阴香、黄荆受害程度中等,在45%—57.5%之间;其它伴生本土种类如鸭脚木、珊瑚树、酒饼叶、等的重要值较低且表现出受害程度较严重。和上层乔木比较,林下植被受污染的伤害大大降低。桉树类树种因其速生、快速郁闭等特点被认为是华南荒山、退化丘陵地区植被恢复的重要种类,但在重度污染地区已面临严重威胁,而某些乡土树种在污染地区则显示出较强的抵御大气污染的能力。本文结果为污染地区森林资源管理,退化生态系统植被恢复之树种选择以及进一步开展乡土树种抵御大气污染胁迫的过程机制与功能特征的研究提供科学基础。 相似文献
20.
Hiley's 1927 paper in the first issue of Forestry argued thateconomics was not just a theoretical discipline, but affectedforestry practice. The long rotations desired by proponentsof forest rental ignored forest capital. Soil rental gave arational basis for choosing silvicultural regime and costingdeviations from the most profitable option. Heavy thinning offeredcompromise between outcomes desired by forest and soil rentalschools. Although Hiley's ideas have influenced British forestry,the forest rental caseis still argued. Development of monetizingtechniques has undermined Hiley's belief that non-market benefitswere ‘imponderable’. It remains importantto separatefour issues: choice of discount rate, treatment of non-marketeffects, construction of performance criteria, and selectionof silvicultural regime. 相似文献