Estimating the value of preserving the Manchurian black bear using the contingent valuation method

Abstract

Although non-consumptive wildlife use is increasingly in demand, its preservation value is not estimated with sufficient accuracy. This study estimates the value of the endangered Manchurian black bear associated with preservation programmes (hereafter, “preservation value”) using a dichotomous choice contingent valuation method in a real-world setting. Since using a hypothetical setting in the contingent valuation method tends to overestimate willingness to pay (WTP), a specially designed field experimental survey was used to incorporate a real-world setting and thereby reduce hypothetical bias, ultimately increasing the accuracy of the estimated WTP. The survey results show that when the responses from the hypothetical setting and real-world setting are compared, the estimated WTP based on the hypothetical setting is higher than that based on the real-world setting. Thus, the real-world setting appears to be effective in terms of reducing hypothetical bias. The preservation value indicated in the real-world setting is estimated at US $4.99 per household for visitors to Chirisan National Park in South Korea, and the annual aggregate preservation value is estimated at US $3.66 million when considering total visitor households. The WTP results show that visitors to Chirisan National Park strongly support preservation programmes for this endangered wildlife species.     

Long-term approaches to native woodland restoration: Palaeoecological and stakeholder perspectives on Atlantic forests of Northern Europe

The long timeframes involved in woodland regeneration and adaptation introduce considerable uncertainty into management and conservation planning as most ecological datasets span only a small part of ecosystem dynamics. This is a particular concern in vulnerable habitats, such as Atlantic birch-oak woods in north-western Britain, where range edge populations are at risk from herbivory and climate change. This study combines historical palaeoecology and stakeholder observations to assess how multiple perspectives can inform existing models, expectations and goals for Atlantic woodland management. Long-term evidence for changing woodland composition addresses stakeholder uncertainties over the currently restricted distribution of oak, alder and hazel. Oak has remained a secondary component of birch-dominated woods and habitat definitions based on oak are too narrow to ensure sustainability. Birch has survived numerous periods of climatic and biotic adversity and shows the strongest positive response to historic reductions in grazing pressure. This has led to a pulse of regeneration since c. AD 1900, so current restoration efforts are taking place within the strongest period of woodland expansion in the last c. 500 years. Positive and negative cultural legacies are evident and intervention is considered a necessary restoration tool. Managed grazing at key stages of habitat development can support continued recruitment and regeneration. A more flexible and integrated management approach is recommended. Long-term ecology can provide direction and address uncertainties, while ecological and stakeholder evidence provide the detail necessary to develop effective management that incorporates ecosystem perspectives. This can help shape management strategies that balance possible conflicts over perceived short-term ‘damage’ to secure longer-term processes. Learning based on multiple temporal perspectives has the potential to contribute to conservation and restoration planning and practice. These principles are more widely applicable in adaptive management.     

Restocking with broadleaved species during the conversion of Tsuga heterophylla plantations to native woodland using natural regeneration

The removal of conifers planted during the twentieth century on sites that had been woodland for many centuries, with the intention of restoring native broadleaved species, is an important aim of forestry policy in Great Britain. Current guidance generally advocates gradual removal of plantation trees using continuous cover silviculture and restocking by natural regeneration, but methods are largely untested. This study investigated natural regeneration of trees and shrubs at sites where western hemlock had been established either pure or in mixture with native broadleaved species. Western hemlock had been cleared from 70% of the sites. There were c. 10?C300 stems ha^?1 providing canopy cover of 10?C90%; the predominant broadleaved canopy trees were ash, beech, birch and oak. The ground flora of all sites was species poor; bramble was the predominant vegetation type overall, but grasses, rushes and shrubs were relatively more abundant on open sites. A total of 15 native tree species were regenerating, birch was most common and at most sites there were few valuable broadleaved timber species. Although combined numbers of seedlings and saplings varied from 200 to 20,000 ha^?1, large areas of most sites had few regenerating trees and <10% of their area was becoming restocked with timber species. Relationships between seedling numbers and site characteristics were complex and varied with species, but there was a consistent positive relationship between the presence of nearby parent trees and the frequency and abundance of seedlings. The results indicate that the current reliance on natural regeneration may be unwise especially for those broadleaved species such as oak and beech which are valued for their timber.     

Estimating stand transpiration in a Eucalyptus populnea woodland with the heat pulse method: measurement errors and sampling strategies

Sap flow measurement techniques, such as the heat pulse (compensation) method, are practical means for estimating the water use of individual trees and are often the only reasonable alternative for measuring forest and woodland transpiration in complex heterogeneous terrain. The need to scale estimates of water use from a sample of individual stems to a stand (population) of known area may be satisfied by applying scalars of flux based on tree size or domain. We estimated the aggregate errors in applying the heat pulse technique to the estimation of stand transpiration in a poplar box (Eucalyptus populnea F.J. Muell.) woodland in southeastern Queensland, Australia, by a combination of precision analyses, experimental validation and Monte Carlo simulations of sampling errors. Errors in sap flux density measurements were approximately 13%. The potential error in the flux estimates for individual stems with stratified sampling of sap flux density with depth and bole quadrant based on four sensors was an additional 25%. Conducting wood area, diameter at 1.3 m, leaf area and domain based on Ecological Field Theory all proved excellent scalars of flux at the stand level. With a sample size of six trees stratified by diameter, coefficients of variation in scaling to the stand level were approximately 5% for any of these scalars. The greatest potential source of error in estimating stand transpiration by the heat pulse method was in the measurement of the fluxes of individual stems; scaling these measurements to a homogeneous stand of trees involved less uncertainty.     

Forest valuation using a two phase inventory method and satellite data

A method is presented for prediction of the present net value (PV) of timber production, based on satellite data and subjectively inventoried forest stand data. Multiple regression analysis was used for predicting the PV. This method has the advantage that predictions of the PV can be made using any kind of existing stand data. The precision of the estimate of the PV, however, depends on the information available in the forest stand database. In the study a combination of Landsat TM data and subjectively inventoried site‐index explained about 75% of the variance, which was equal to the case when all subjective ground stand data, excluding TM data, were used to predict PV. This result and results from other data combinations suggest that Landsat TM data might be useful for forest management planning.     

The role of social and environmental attitudes in non-market valuation: An application to the Białowieża Forest

The purpose of this study is to investigate the impact of non-economic motivations such as altruism and environmental concerns on social preferences and hence willingness to pay (WTP) for changes in forest management strategies in the Białowieża Forest in Poland. We used data from a discrete choice experiment (CE) with attributes describing changes in the quality of the forest and recreation. The choice experiment technique makes it possible to disentangle the effect of the trait of altruism and environmental concern with regard to different attributes and their levels. Environmental attitudes were measured using the New Ecological Paradigm (NEP) scale, whereas the trait of altruism was determined using the Self-Reported Altruism (SRA) scale. The parameterization employed in the survey was a WTP space model. Results show that both altruism and environmental concerns have significant effects on the amount people are willing to pay for changes in forest management.     

攀西干热河谷退耕还林模式及效益评估

针对攀西地区干热河谷的生态环境 ,提出了适合不同立地条件的退耕还林的造林技术模式。论述了经济林模式、生态林模式、用材林模式和林草混交立体模式的适用立地条件、造林树种配置 ,并通过经济分析方法对攀西地区 1 4种主要退耕还林模式进行了经济效益评价     

Valuing the benefits to the local community of supplying recreational facilities in community owned forests: an application of the contingent behaviour method

This research utilises a contingent behaviour valuation technique to value a number of improvements to recreational facilities in small-scale forests in Ireland. Willingness-to-pay estimates have previously been made for Coillte (Ireland’s state-owned forestry company) trails and forests. The total non-market value of Irish forests has also been examined. This paper adds to the literature by being the first to estimate the consumer surplus associated with recreational enhancements to Irish small-scale forest resources. The results presented indicate that community owned small-scale forestry can contribute enormously to the wellbeing of nearby urban residents, through the provision of outdoor recreational services.

退耕还林的关键技术措施及保障体系

针对安徽省近年来退耕还林工程建设的实施情况，探讨了退耕还林工程方案设计原则，并对退耕还林工程科技支撑方案的内容进行了简要的阐述，供林业部门在实施退耕还林工程时参考。     

The costs and benefits of REDD+: A review of the literature

The costs and benefits of the Reducing Emissions from Deforestation and Forest Degradation (REDD⁺) projects are often reported in isolation. There is a lack of comprehensive understanding of the types of REDD⁺ costs and benefits reported in the literature. In this paper, we conducted a review of 60 unique REDD⁺ costs and benefits studies. We found that no single study covers all categories of costs and benefits in a comparable form. A total of 56 comparable estimates were available for opportunity costs, 21 for transaction and implementation costs, 23 for total costs, and only four for direct monetary benefits. We found that, on average, the total REDD⁺ cost ($24.87/tCO₂e) was 2.23 times higher than the opportunity cost and the opportunity cost was 3.28 times higher than the transaction and implementation costs. Costs estimates among studies vary widely based on estimation approach used and the scale of the studies. We noted that future REDD⁺ costs and benefits studies should provide estimates of all relevant costs and benefits, and the distribution of these costs and benefits among project stakeholders. These findings have implications in REDD⁺ project design and implementation.     

Using a geographic information system to estimate an hedonic price model of the benefits of woodland access

The hedonic price method may be used to investigate the effectthat the attributes of a product have on its market price. Inthe case of housing, this methodology has been used to lookat the premium that the amenity offered by nearby woodland addsto house prices. The interpretation of the results of thesestudies is difficult and is the subject of some debate. In particular,it has been argued that the aesthetic benefits of woodland,as a component of landscape, cannot be enumerated using thehedonic approach. This paper adopts a broader approach and useshedonic pricing to estimate the amenity benefits gained by localresidents from access to woodland. To accomplish this a geographicinformation system is used to improve the data available tothe hedonic price model from which estimates of the residentialaccess benefits of woodland are derived     

Estimating root mass in young hybrid poplar trees using the electrical capacitance method

A preliminary field study was conducted on root mass of young hybrid polar trees (Populus deltoides x P. nigra) using the electrical capacitance method. The objective of this study was to develop a simple calibration relationship that would enable root mass (fresh or dry) to be estimated for young hybrid poplar trees grown in mineral soils using simple, non-intrusive measurements of electrical capacitance. For first-year potted saplings (n = 33), strong linear and positive correlations were found between both root dry mass (adjusted r² = 0.895, P<0.001) and root fresh mass (adjusted r² = 0.866, P<0.001) and root electrical capacitance for the particular DN hybrid poplar clone studied. When augmented with data from third-year DN saplings grown in a more harsh landfill environment, a somewhat less strong curvilinear relationship was indicated with root dry mass (adjusted r² = 0.780, P<0.001, n = 50). This rapid field method may be capable of providing adequate estimates of root mass for young trees in a variety of applications, such as afforestation, agroforestry or phytoremediation studies. This revised version was published online in June 2006 with corrections to the Cover Date.     

毛竹覆盖-套种竹荪轮作模式经济效益和生态修复评价

在花年毛竹纯林进行1a覆盖-1a套种竹荪轮作等经营模式试验,研究毛竹林覆盖后套种竹荪轮作模式经济效益和生态修复作用。结果表明：(1)1 a覆盖-1 a套种竹荪轮作模式的2 a净收入达到18.0万元/hm2,投入产出比达到1∶3.29,分别是传统单一经营模式、1 a覆盖-1 a自然培育经营模式的19.6倍和1.6倍。(2)毛竹林覆盖后套种竹荪轮作模式在高碳氮比(C/N)有机物覆盖的清理、林地土壤改良、林地地力培育等生态修复效果明显优于1 a覆盖-1 a自然培育经营模式,有效防止竹林地因覆盖而引发竹林衰退。毛竹林覆盖与套种竹荪轮作模式是毛竹林可持续性发展的经营模式,可作为毛竹林覆盖的配套经营措施在生产上推广应用。     

Estimating sap flux densities in date palm trees using the heat dissipation method and weighing lysimeters

In a world of diminishing water reservoirs and a rising demand for food, the practice and development of water stress indicators and sensors are in rapid progress. The heat dissipation method, originally established by Granier, is herein applied and modified to enable sap flow measurements in date palm trees in the southern Arava desert of Israel. A long and tough sensor was constructed to withstand insertion into the date palm's hard exterior stem. This stem is wide and fibrous, surrounded by an even tougher external non-conducting layer of dead leaf bases. Furthermore, being a monocot species, water flow does not necessarily occur through the outer part of the palm's stem, as in most trees. Therefore, it is highly important to investigate the variations of the sap flux densities and determine the preferable location for sap flow sensing within the stem. Once installed into fully grown date palm trees stationed on weighing lysimeters, sap flow as measured by the modified sensors was compared with the actual transpiration. Sap flow was found to be well correlated with transpiration, especially when using a recent calibration equation rather than the original Granier equation. Furthermore, inducing the axial variability of the sap flux densities was found to be highly important for accurate assessments of transpiration by sap flow measurements. The sensors indicated no transpiration at night, a high increase of transpiration from 06:00 to 09:00, maximum transpiration at 12:00, followed by a moderate reduction until 08:00; when transpiration ceased. These results were reinforced by the lysimeters' output. Reduced sap flux densities were detected at the stem's mantle when compared with its center. These results were reinforced by mechanistic measurements of the stem's specific hydraulic conductivity. Variance on the vertical axis was also observed, indicating an accelerated flow towards the upper parts of the tree and raising a hypothesis concerning dehydrating mechanisms of the date palm tree. Finally, the sensors indicated reduction in flow almost immediately after irrigation of field-grown trees was withheld, at a time when no climatic or phenological conditions could have led to reduction in transpiration.     

Economic evaluation of financial and non-financial costs and benefits in agroforestry development and the value of sustainability

Financial appraisal of agroforestry is not different in kind from appraisals applied to pure forestry. Existing techniques for valuing non-market effects may also be applied. Effects on hydrological and carbon fluxes might be less favourable than those of pure forests. In the confusing field of biodiversity valuation too, only limited and specific claims can be made for agroforestry. Amenity valuation techniques developed for trees and woodlands encounter additional problems of interpretation in an agroforestry context. Agroforestry may offer a quantifiable value in short-term sustainability, and might meet recent economic definitions of long-term sustainable development, without encountering the full dangers to future generations embodied in conversion of natural to human capital.     

Reforestation with native tree species using site preparation techniques for the restoration of woodlands degraded by air pollution in the Erzgebirge,Germany

Reforestation of woodlands with native species in the Erzgebirge, where large-scale deforestation has been caused by severe air pollution, was investigated. In an experiment, three tree species (Norway spruce, rowanberry, and birch) were studied with regard to fencing (no protection versus protection against game browsing) and site preparation techniques with eight levels: a control and seven amelioration techniques (soil cultivation, weed control, liming, and their combinations). Four criteria, survival, growth, production, and vitality, were used in assessing the success of the plantings. Repeated-measures analyses were performed to examine the development of the young plantations over an observation period of 7 years, and to determine whether this development was dependent on the experimental factors. Spruce showed high survival rates, reasonable growth and production, and good individual vitality. With the exception of survival, birch responded similarly to spruce. The low survival rate of birch resulted from the initial small size of the seedlings. By providing appropriate seedling material, both species could be used for reforestation. Seedlings of rowanberry were unsuccessful due to severe mouse damage, confirming the necessity of rodent control when planting cleared areas with this species is undertaken. Game browsing was not significant. None of the amelioration techniques had a major effect on the studied criteria of the three tree species. Slightly positive effects occurred only when spruce was limed and when birch received soil cultivation. Weed control by scything showed undesirable results, particularly for birch. For reasons of financial thriftiness, none of the amelioration techniques could be justified for the study area.     

云南省退耕还森地可持续发展技术

云南省是全国耕还林（草）的重点地区，生态环境处于不断恶化的趋势中，人口－资源－环境的矛盾较为突出，通过对云南省退耕还林情况的分析，提出了退耕还林地可持续发展的集成配套技术措施是：进行合理的空间布局和林种配置，采用生态经济兼优的多余树种营建生态经济林、推广等高固氮植物篱技术和混农林业经营等。     

Effects of overstorey retention on ash regeneration and bramble growth during conversion of a pine plantation to native broadleaved woodland

Conversion of monoculture plantations to mixed stands with greater diversity is an important aim of sustainable forest management, and in Britain, this is concentrated on the restoration of native broadleaved woodland on ancient woodland sites that were planted with conifers. Current British guidelines for this restoration have rarely been examined, and this study is the first to test their value for natural regeneration. The survival and growth of naturally regenerating ash (Fraxinus excelsior L.) seedlings was observed in thinned, selectively felled and clearfelled plots within a c. 40-year-old stand of Corsican pine (Pinus nigra Arnold ssp. laricio Maire). After felling in 2001, the ground flora in all treatments became dominated by bramble (Rubus fruticosus L. agg.) and its cover 5 years after felling was 75–95?% at a height of 0.9–1.2?m. During the study, seedling numbers declined 80–90?%. Although bramble had some adverse effects, seedling survival was unaffected by felling treatment. Seedling growth varied between treatments with those in the clearfell being tallest. Mean height of seedlings was always less than that of bramble, but by 2006 65?% of quadrats in the clearfelled plots had well-established individuals taller than the bramble compared with 35?% in the thinned plots. Models that described the relationships between seedling growth, basal area and bramble were complex, but results clearly indicate that maintaining canopy cover during restoration is probably an ineffective method of suppressing bramble on sites where it grows well. Results do not support the current British advice on conversion, but this may reflect the characteristics of pine canopies and the maintenance of canopy cover during conversion may be appropriate in stands of species, which cast more shade.