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1.
Summary

The Massachusetts Woodlands Cooperative, LLC (MWC) is working to help members conduct sustainable forestry of the highest standards while increasing financial returns from harvest activities. The forests of Massachusetts, the third most densely populated state in the United States, are threatened. Decades of high grading and the threat of forest conversion to alternative use present challenges for maintaining a forested landscape. Despite being 60% forested, Massachusetts imports approximately 98% of the wood fiber that its citizens consume.

The Massachusetts Woodlands Cooperative is a forest management, processing, and marketing cooperative organized by and on behalf of forest landowners in western Massachusetts. An umbrella group certification protocol was developed to provide cost-effective forestland management certification. Members benefit from cooperative management of harvest operations, above-market stumpage payments, and value-added processing and production including marketing traditionally low-value and small-diameter material. The added revenue from developing these new markets is used to fund timber, wildlife habitat, recreation, and other sustainable forest management activities. The cooperative works in partnership with local wood-processing businesses to spur community economic development. This study on cooperatives may be a successful example of sustainable forest management that can be applied in other regions with private land ownerships.  相似文献   

2.
Abstract

This paper comparatively examines two forest management planning approaches: multipurpose forest management and traditional timber management, with carbon, timber and oxygen production objectives in mind. The effects of both approaches on carbon and oxygen values were estimated with an oxygen and carbon flow matrix, while timber production was modelled through a growth and yield model. The estimated values were simultaneously integrated into a linear programming model developed for this study. The objective was to maximize the net present value (NPV) of the profits of timber, oxygen and carbon under the constraints of an even flow of timber production and ending forest inventory for each planning approach. The results showed that the ecological and environmental regulations in multipurpose management substantially decreased the NPV of timber production even though they increased the NPV of carbon and oxygen flow. The results also indicated that over a 100 year planning horizon the total NPV of all forest ecosystem values including carbon, timber and oxygen is almost the same (only 1.9% reduction in multipurpose management approach) in both management approaches. Although multipurpose management creates more NPV of carbon and oxygen than timber management does, the latter provides better results in terms of timber production. It is therefore important to take into account the NPV of all apparent and quantifiable forest values in preparing forest management plans, particularly in developing new management planning approaches.  相似文献   

3.
Forest management has been criticised in the last 20 years for its negative impact on the native species, structures and functions of the forest. Of many possible alternatives proposed to minimize these effects, the functional zoning (or TRIAD) approach is gaining popularity in North America. The goal of this approach is to minimize the negative environmental impacts of forestry while maintain timber supply by dividing the forest into three broad land-use zones: (1) conservation, (2) ecosystem management, and (3) wood production. In this study, we used a spatially explicit landscape model to simulate the effects of fire and six different forest management scenarios on a boreal mixedwood forest management unit in central Quebec. The management scenarios examined included the current practices scenario, a scenario proposed by the provincial government, and four TRIAD scenarios varying in the amount of forest allocated to each of the three zones. For each scenario, we examined the harvest volume, percentage old-growth forest or old forest managed to favour old-growth attributes, and effective mesh size of forest patches by 20-year age classes. With more area set aside for conservation and high-retention partial cut harvesting techniques designed to maintain the attributes of old-growth stands, all TRIAD scenarios resulted in higher percentages of stands with old-growth attributes than the current practices scenario and the government proposed scenario, and two of the four TRIAD scenarios also resulted in higher harvest volume over the long term. All forest management scenarios resulted in significantly lower effective mesh size than the fire-only scenario, but this difference was not as pronounced for the four TRIAD scenarios as for the current practice and government proposed scenarios. We conclude that the TRIAD approach has the potential to minimize some of the negative impacts of forestry on the landscape, while maintaining timber supply over the long term.  相似文献   

4.
The sample plot data of National Forest Inventories (NFI) are widely used in the analysis of forest production and utilization possibilities to support national and regional forest policy. However, there is an increasing interest for similar impact and scenario analyses for strategic planning at the local level. As the fairly sparse network of field plots only provides calculations for large areas, satellite image data have been applied to produce forest information for smaller areas. The aim of this study was to test the feasibility of generating forest data for a Finnish forest analysis tool, the MELA system, by means of the Landsat satellite imagery and the NFI sample plot data. The study was part of the preparation of a local forestry programme, where a strategic scenario analysis for the forest area of two villages (ca 8000 ha) was carried out. Management units that approximate forest stands were delineated by image segmentation. Stand volume and other parameters for each forest segment were estimated from weighted means of the NFI sample plots, where the individual sample plot weights were estimated by the k nearest neighbour (kNN) method. Two different spectral features were tested: single pixel values and average pixel values within a segment. The estimated forest data were compared with the forest data based on independent stand-level field assessments in two subareas, a national park and an area of forest managed for timber production.In the national park, the estimated mean volume of the growing stock from both spectral feature sets (about 160 m3 ha−1) was clearly lower than that obtained from stand-level field assessment (186 m3 ha−1). Using average pixel values within a segment resulted in a higher proportion of pine and a lower proportion of spruce volume than using single pixel values. It also resulted in an estimated felling potential nearly 10% higher over the first 10-year period in the scenario analysis of the area dedicated to timber production. However, the maximum long-term sustainable removal was at the same level (about 30,000 m3 year−1) for both feature sets over the simulated 30-year period. The resulting annual felling area in the first 10-year period was 12% lower when the segment averages were applied, but the difference subsequently levelled off. The kNN approach in estimating initial forest data for scenario analyses at the local level was found promising.  相似文献   

5.
The threat of climate change is now recognized as an imminent issue at the forefront of the forest sector. Incorporating adaptation to climate change into forest management will be vital in the continual and sustainable provision of forest ecosystem services. The objective of this study is to investigate climate change adaptation in forest management using the landscape disturbance model LANDIS-II. The study area was comprised of 14,000 ha of forested watersheds in central Nova Scotia, Canada, managed by Halifax Water, the municipal water utility. Simulated climate change adaptation was directed towards three components of timber harvesting: the canopy-opening size of harvests, the age of harvested trees within a stand, and the species composition of harvested trees within a stand. These three adaptation treatments were simulated singly and in combination with each other in the modeling experiment. The timber supply was found to benefit from climate change in the absence of any adaptation treatment, though there was a loss of target tree species and old growth forest. In the age treatment, all trees in a harvested stand at or below the age of sexual maturity were exempt from harvesting. This was done to promote more-rapid succession to climax forest communities typical of the study area. It was the most effective in maintaining the timber supply, but least effective in promoting resistance to climate change at the prescribed harvest intensity. In the composition treatment, individual tree species were selected for harvest based on their response to climate change in previous research and on management values at Halifax Water to progressively facilitate forest transition under the altered climate. This proved the most effective treatment for maximizing forest age and old-growth area and for promoting stands composed of climatically suited target species. The size treatment was aimed towards building stand complexity and resilience to climate change, and was the most influential treatment on the response of timber supply, forest age, and forest composition to timber harvest when it was combined with other treatments. The combination of all three adaptation treatments yielded an adequate representation of target species and old forest without overly diminishing the timber supply, and was therefore the most effective in minimizing the trade-offs between management values and objectives. These findings support a diverse and multi-faceted approach to climate change adaptation.  相似文献   

6.
In many areas, picking wild berries constitutes an important forest commodity offering food, recreational services, and revenues. Intensified forest management has negatively affected bilberry yields. In this study, regional-level scenario analyses were conducted to investigate the effects of four approaches to the inclusion of bilberry yields on the economics, management, and resulting forest structures in North Karelia. The current approach ignoring bilberries resulted in decreasing bilberry yields and increasing younger forests. When bilberries were valued at market price (1.72?€?kg?1), bilberry yields still decreased despite the fact that forest management were slightly modified to favour bilberry. Adding non-declining sustainability constraints to bilberry yields resulted in a slightly lower total net present value of timber and bilberry since forest management favoured longer rotation lengths, which increased bilberry yields. Similar effects occurred when the bilberry price was tripled to include the implicit ecosystem benefits of bilberries. When forests were managed only for bilberries (timber zero-priced), bilberry yields started to increase immediately resulting in 1.5-fold difference in 50 years as compared to timber only scenario. In conclusion, managing forests for both timber and bilberry production has rather minor effects on economics, but it can have clear positive effect on bilberry yields.  相似文献   

7.
In this study, the overall utility of forest management alternatives at the forest management unit level is evaluated with regard to multi-purpose and multi-user settings by a multi-criteria analysis (MCA) method. The MCA is based on an additive utility model. The relative importance of partial objectives of forest management (carbon sequestration, ground water recharge, biodiversity, and timber production) is defined in cooperation with stakeholders. The forest growth model 4C (Forest Ecosystems in a Changing Environment) is used to simulate the impact of six forest management strategies and climate on forest functions. Two climate change scenarios represent uncertainties with regard to future climatic conditions. The study is based on actual forest conditions in the Kleinsee management unit in east Germany, which is dominated by Scots pine (Pinus sylvestris L.) and oak (Quercus robur L. and Quercus petraea Liebl.) stands. First, there is an analysis of the impact of climate and forest management on forest functions. Climate change increases carbon sequestration and income from timber production due to increased stand productivity. Secondly, the overall utility of the management strategies is compared under the priority settings of different stakeholder groups. From an ecological perspective, a conservation strategy would be preferable under all climate scenarios, but the business as usual management would also fit the expectations under the current climate due to high biodiversity and carbon sequestration in the forest ecosystem. In contrast, a forest manager in public-owned forests or a private forest owner would prefer a management strategy with an intermediate thinning intensity and a high share of pine stands to enhance income from timber production while maintaining the other forest functions.  相似文献   

8.
Restoring altered forest landscapes toward their ranges of natural variability (RNV) may enhance ecosystem sustainability and resiliency, but such efforts can be hampered by complex land ownership and management patterns. We evaluated restoration potential for southern-boreal forests in the ∼2.1 million ha Border Lakes Region of northern Minnesota (U.S.A.) and Ontario (Canada), where spatially distinct timber harvest and fire suppression histories have differentially altered forest conditions (composition, age–class distribution, and landscape structure) among major management areas, effectively resulting in forest landscape “bifurcation.” We used a forest landscape simulation model to evaluate potential for four hypothetical management and two natural disturbance scenarios to restore forest conditions and reduce bifurcation, including: (1) a current management scenario that simulated timber harvest and fire suppression practices among major landowners; (2) three restoration scenarios that simulated combinations of wildland fire use and cross-boundary timber harvest designed to emulate natural disturbance patterns; (3) a historical natural disturbance scenario that simulated pre-EuroAmerican settlement fire regimes and windthrow; and (4) a contemporary fire regime that simulated fire suppression, but no timber harvest. Forest composition and landscape structure for a 200-year model period were compared among scenarios, among major land management regions within scenarios, and to six RNV benchmarks. The current management scenario met only one RNV benchmark and did not move forest composition, age–class distribution, or landscape structures toward the RNV, and it increased forest landscape bifurcation between primarily timber-managed and wilderness areas. The historical natural disturbance scenario met five RNV benchmarks and the restoration scenarios as many as five, by generally restoring forest composition, age–class distributions, and landscape structures, and reducing bifurcation of forest conditions. The contemporary natural disturbance scenario met only one benchmark and generally created a forest landscape dominated by large patches of late-successional, fire-prone forests. Some forest types (e.g., white and red pine) declined in all scenarios, despite simulated restoration strategies. It may not be possible to achieve all objectives under a single management scenario, and complications, such as fire-risk, may limit strategies. However, our model suggests that timber harvest and fire regimes that emulate natural disturbance patterns can move forest landscapes toward the RNV.  相似文献   

9.
Abstract

In many countries of Africa and Asia, timber production is dominated by concession contracts in public forests. In the neo-tropics, however, timber production occurs on both public and private lands; a mixture that moves countries of the neo-tropics towards the complex systems of forestry sectors in the developed world. Therefore, much of the forest taxation and public forest management literature that currently exists is pertinent to new forest policy decisions in developing countries. Unfortunately, the similarities between forest policies in the neo-tropics and those of developed countries have largely been ignored. This paper begins the process of bridging that gap to show how existing literature is important to the design of timber concessions and accompanying policy instrument design. Although the principles we discuss here apply in any mixed harvest forest economy, we use Brazil as an example because it is in the process of adopting a system of timber concessions in national forests. In our discussion, we suggest that concessions are not a perfect substitute for private forestry in the neo-tropics; concession and other instrument policies must be designed jointly; and because concession policies and government revenue objectives may be linked, the expansion of concessions must be carefully monitored.  相似文献   

10.
Abstract

At present Nepal's demand for forest products exceeds its production. The Sagarnath Forest Development Project with its 10,000 hectares in sissoo and eucalyptus plantations may fulfill part of the country's requirement of firewood and timber products. To ensure the sustainable management of these plantations, a harvesting plan was developed. Linear programming was applied to obtain optimal harvesting levels. Models for both sissoo and eucalyptus were run with and without nondeclining, and even flow constraints separately. Linear Interactive and Discrete Optimizer (LINDO) was used to run these models. The plan with even flow constraints was found to be the best fulfilling the demands of both timber and fuelwood to some extent and making the harvest financially sustainable.  相似文献   

11.

Intensive forest management has changed both local and regional characteristics of Fennoscandian forest. However, quantitative documentation of landscape transformations is rare. In this study, five forest landscapes were examined in order to define and quantify forest landscape transformation in southern Finland from the 1940s to the 1970s and 1990s. These areas of 140-200 km2 contained both private and state-owned forests. Digital aerial photographs of each area were classified into no-canopy forest (clear-cut and seedling stands, open mires) and closed-canopy forest (young and mature stands). Patch density, mean patch size, largest patch index and edge density calculated for closed-canopy patches indicated fragmentation from the 1940s to the 1970s and recovery from the 1970s to the 1990s. Trends were very similar in both ownership groups. Thus, fragmentation of closed-canopy forests has not progressed continuously in southern Finland, but shows different patterns depending on the period. However, the recovery observed between the 1970s and 1990s does not necessarily mean an increased abundance of the natural old-growth areas that are needed to host many of the currently threatened species.  相似文献   

12.

Efficient forest management, and wood production in particular, requires a forest road network of appropriate density and bearing capacity. The road network affects the choice of a suitable extraction method and the length of the transport route from the forest, while the road standard defines the truck type that can be used.

We evaluate the forest road network’s economic suitability for harvesting operations in the entire Swiss forest, an area of about 13,000 km2 covering a range of topographies, based on the Swiss National Forest Inventory’s (NFI) forest road dataset. This dataset is based on information from an interview survey with the local forest services and includes all forest roads in Switzerland capable of carrying trucks. Extraction options and hauling routes are analysed together; thus, the entire logging process is examined.

Model results include maps of the most suitable extraction method; extraction costs; hauling costs; and a suitability map based on a combination of the results. While the larger part of the Swiss forest is classified as “suitable” for economic harvesting operations, significant portions also fall into the “limited suitability” and “not suitable” categories. Our analysis provides an objective, country-wide, spatially explicit assessment of timber accessibility. The resulting suitability map helps identify areas where timber harvesting is economic using the current forest road network, and where it is not. The model results can be used in road network planning and management, for example, by comparing road-network re-design scenarios, and compared to the spatial distribution of available wood volume.

  相似文献   

13.
This study assessed the sustainability of selection cutting in a community forest (CF) in Bhutan. The harvesting approach differed from cable crane logging operations in an adjacent commercially managed forest by creating much smaller canopy openings. This had many implications for natural regeneration of preferred species. The study was conducted in a late successional broadleaved CF containing 32 genera of tree species dominated by Quercus and Castanopsis and managed for timber, firewood, non-wood forest products and forest grazing. The study was based on a comparison of two forest inventories to assess forest structure and regeneration, a study of stumps to quantify harvesting intensities, and a household survey to quantify livestock holdings and grazing patterns. The study examined different intensities of selection cutting in three blocks of the CF and found that higher intensities of selection cutting did not have a negative impact on: (a) natural regeneration of seedlings and saplings of preferred timber species; (b) the diameter distribution of all species and use categories except for Quercus; (c) the diversity of tree genera; and (d) the percentage of remaining trees with favorable bole shape and form. These results contrasted with findings in the adjacent commercially managed forest. Community management of broadleaved forests with selection cutting appeared to be sustainable and avoid some of the unresolved silvicultural problems associated with commercially managed forests in Bhutan. However more research is needed on the sustainable management of Quercus spp.  相似文献   

14.
Abstract

To be able to make the right decisions in forestry today, the long-term effect of these decisions has to be considered. Multi-objective forest landscape projection models are tools that can be used to illustrate the effect of different management alternatives in a landscape. An integrated approach facilitates multi-objective considerations and decisions. A number of modelling systems has been developed. A modelling system contains numerous sub-models, each one modelling a particular part of the forest ecosystem, the socio-economy or other aspects of interest. Models and data are intimately connected, and different methods for collecting data and their relevance for different models are examined. The sub-models interact with each other in such a way that the dynamics of a forest is simulated.

This article examines different sub-models for tree growth, economy, biodiversity, forest recreation and soil, and various uses for multi-objective forest landscape projection models are suggested and some examples are presented. Almost every model is associated with variation, uncertainty, and underlying assumptions. Errors in data and models, their origin and propagation through models, are discussed. The future development of forest models and their employment in planning and decision making are considered.  相似文献   

15.
Abstract

This paper presents empirical insight into part-time and full-time property owners’ perceptions of risk and risk management strategies. In addition, the relationships between forest owners with varying degree of off-property work and property and forest owner characteristics, risk perceptions, risk management strategies and harvesting behaviour are examined. The data originate from a questionnaire responded to by forest owners in eastern Norway which were merged with 9 years of logging data. Timber price variability and institutional risks were perceived as primary sources of risk. Use of advisers from the forest owners’ association, buying personal insurance and off-property work were perceived as the most important ways to handle risk. The results show that off-property work affects to a lesser degree what forest owners perceived as important risk sources, but that risk perceptions affect to a stronger degree the ways in which risk was dealt with. The chosen risk management strategies influenced the forest owner's harvesting behaviour to some extent, but more research on the issue is needed to clarify the relationship. There was a positive relationship between owners with off-property activities and their performance as timber suppliers. Several measures, such as improved rural education, revision of some of the arrangements that regulate property mergers and support measures for increased on-property diversification may increase annual timber harvesting and reduce variability in harvesting level.  相似文献   

16.
Increased forest biomass production for bioenergy will have various consequences for landscape scenery, depending on both the landscape features present and the character and intensity of the silvicultural and harvesting methods used. We review forest preference research carried out in Finland, Sweden and Norway, and discuss these findings in relation to bioenergy production in boreal forest ecosystems. Some production methods and related operations incur negative reactions among the public, e.g. stump harvesting, dense plantation, soil preparation, road construction, the use of non-native species, and partly also harvest of current non-productive forests. Positive visual effects of bioenergy production tend to be linked to harvesting methods such as tending, thinning, selective logging and residue harvesting that enhance both stand and landscape openness, and visual and physical accessibility. Relatively large differences in findings between studies underline the importance of local contextual knowledge about landscape values and how people use the particular landscape where different forms of bioenergy production will occur. This scientific knowledge may be used to formulate guiding principles for visual management of boreal forest bioenergy landscapes.  相似文献   

17.
Understanding long-term changes in forest ecosystem carbon stocks under forest management practices such as timber harvesting is important for assessing the contribution of forests to the global carbon cycle. Harvesting effects are complicated by the amount, type, and condition of residue left on-site, the decomposition rate of this residue, the incorporation of residue into soil organic matter and the rate of new detritus input to the forest floor from regrowing vegetation. In an attempt to address these complexities, the forest succession model LINKAGES was used to assess the production of aboveground biomass, detritus, and soil carbon stocks in native Eucalyptus forests as influenced by five harvest management practices in New South Wales, Australia. The original decomposition sub-routines of LINKAGES were modified by adding components of the Rothamsted (RothC) soil organic matter turnover model. Simulation results using the new model were compared to data from long-term forest inventory plots. Good agreement was observed between simulated and measured above-ground biomass, but mixed results were obtained for basal area. Harvesting operations examined included removing trees for quota sawlogs (QSL, DBH >80 cm), integrated sawlogs (ISL, DBH >20 cm) and whole-tree harvesting in integrated sawlogs (WTH). We also examined the impact of different cutting cycles (20, 50 or 80 years) and intensities (removing 20, 50 or 80 m3). Generally medium and high intensities of shorter cutting cycles in sawlog harvesting systems produced considerably higher soil carbon values compared to no harvesting. On average, soil carbon was 2–9% lower in whole-tree harvest simulations whereas in sawlog harvest simulations soil carbon was 5–17% higher than in no harvesting.  相似文献   

18.
[目的]探讨用于快速更新森林资源数据库的森林变化检测方法,监测短时期内森林采伐与更新的动态变化。[方法]以变化频繁快速,高度集约经营的广西上思县人工林作为研究区,以两个时相的高分二号遥感影像作为数据源,分别利用红波段、近红外波段和NDVI 3种特征的影像差值,并基于分布函数确定阈值,对研究区进行快速的变化检测,并提取变化区域和变化类型。[结果]表明,3种特征差值的检测精度排序为:NDVI差值法最优,红波段差值法次之,近红外波段差值法最差。其中NDVI的总体精度为87.12%,Kappa系数为0.76,[结论]该方法在实现快速检测变化的目的下,可用于森林资源数据库的更新。  相似文献   

19.

The state of mixed forests of maritime pine ( Pinus pinaster Ait.) and broadleaved species in the coastal region of Galicia (north-western Spain) was described using data from 213 circular sample plots selected among the available 4700 plots of the Spanish National Inventory. A matrix model was developed for this forest type to obtain information about the productivity and potential for sustainable management. The broadleaved species had a diameter distribution close to the inverted J-shape typical of the uneven-aged forests but for maritime pine there were many medium-sized trees and a lack of trees in the first diameter class of 15 cm. The matrix growth model was used to predict the development of mixed forests for three different management options: no harvesting in a well-stocked stand, a regime with a 5 yr harvest cycle and a residual basal area of 15 m 2 ha -1 in a well-stocked stand, and a rehabilitation management applied to an understocked stand. The results showed the possibility of applying uneven-aged silvicultural systems to these forests, leading to the production of high-value timber and to the maintenance of continuous cover and a biodiverse forest.  相似文献   

20.
城郊森林公园是提升大众福祉、发挥生态功能的载体。以广东西樵山国家森林公园为研究对象,运用 ArcGIS 软件和Fragstats软件对其景观格局进行分析。结果表明,风景林是公园景观的基质(PLAND =67.84%),道路廊道将其与用材林、建筑和水体3种主要景观类型进行串联;公园各景观类型的破碎化程度不同,斑块形状均较为规则(MSI值为1.41~2.12;MPFD值为1.10~1.24);公园的景观多样性较低(SHDI=1.31),斑块空间分布不均(SHEI=0.53),斑块形状较为复杂(LSI=22.83),各功能分区的格局特征差异明显。城郊森林公园的经营应严格控制人为干扰影响,提高公园景观多样性,注重斑块类型、功能分区和整体景观格局的优化。  相似文献   

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