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1.
The objective of this study is to evaluate preferences for time paths of outputs arising from alternative forest management practices. A discrete choice framework using logit and mixed logit models is used to evaluate stated choices by Public Advisory Committee members over attributes regarding inter-temporal forest management options. Results of the study indicate a relatively strong preference for physical sustainability, or even flow choices. However, respondents appear to be more accepting of uneven flows in recreation services than they are of uneven flows of timber harvests. Results also provide yet another illustration of a difference in implied rates of discount over the goods involved (i. e. timber versus recreation). The paper illustrates a mechanism for use in public involvement exercises that may identify inter-temporal preferences over forest management plans and strategies.  相似文献   

2.
Comparisons of the costs of reduced-impact (RIL) and conventional logging (CL) based on new data from Gabon and 10 previously published studies revealed that some tropical forest operators should adopt RIL out of financial self-interest but many may require other motivation. Among the comparisons in which costs were expressed per cubic meter of harvested timber, three reported lower costs for RIL, one showed identical costs with CL, and six reported RIL to be more costly.  相似文献   

3.
To improve the economies of scale in forest management and reduce the fragmentation of forestland, the Chinese central government has implemented a collective forest tenure supplementary reform since 2008. This has included a series of policies for motivating transfer of forestlands use rights among households in the country’s Southern Collective Forest Area (SCFA). However, to date there is little evidence that large-scale forest owners can earn more profits from timber harvests than small-scale forest owners in the SCFA. Using data collected from household surveys in the three of the SCFA’s provinces in 2016, this paper examines the return to scale of forestland ownership for timber harvests in this region, and how the scale of forestland ownership affects households’ profits from timber harvests. The results show a constant return to scale in timber harvests in the case provinces in China’s SCFA, that forestland area makes the most important contribution to the output of timber harvests, and that fragmentation of forestland results in lower profits from timber harvests. It appears that a moderate scale of forestland ownership should be identified for increasing the profits from timber harvests. With the rapid urbanization throughout China, an increase in off-farm employment among rural household members has a negative impact on timber harvests in the region. We argue that policymakers should realize the importance of encouraging the forestland transfers and improve the concentration of forestlands in the next stage of forest tenure rights reform in China’s SCFA.  相似文献   

4.
Managing Mississippi's forest lands to produce both quality wildlife habitat as well as merchantable timber can be a daunting challenge for forest managers and a source of great concern for the public. In some cases, producing both the quantity and quality of habitat needed and the timber desired is all but impossible. In other cases, a delicate balance that achieves both objectives can be struck. The objective of this study was to quantitatively estimate monetary gains and losses and changes in timber inventories relative to the timber growing stock when producing more or less habitat for the red-cockaded woodpecker (RCW) (Picoides borealis). USDA Forest Service vegetation data, habitat ratings, and economic variables were compiled for those regions of Mississippi best suited for RCWs. Data was then analyzed with Spectrum, the USDA Forest Service-based forest planning software. Models maximizing such objectives as net present value (NPV) alone as well as five different levels of RCW habitat quality over a 50-year rotation were developed. Revenue foregone, acres and volumes harvested, land expectation value (LEV), and equivalent annual income (EAI) were compared for all objectives for the South Central Hills and Pine Belt regions of Mississippi (1,036,208 acres) for three ownership types. As expected, when maximizing for any quality level of RCW habitat, revenue forgone was higher ($0.11–$49/acre/year) than for NPV alone. Volume harvested for high-quality habitat ranged from 152,296 to 10,237,649 cunits, while harvests from low-quality habitat ranged from 637,491 to 116,357,673 cunits. Lower levels of habitat management allowed for an increased emphasis on timber harvesting. In general, we determined that increases in habitat quality resulted in lower timber harvest levels and increased revenue forgone than regimes maximizing NPVs. While this result may be expected, of greater importance are the relative differences between regimes and the ability to use these values for policy decisions.  相似文献   

5.
This study estimates the supply potential and annual availability of timber and forest biomass resources under profitable forest management in Japan. It focuses on four prefectures, namely, Fukushima, Ibaraki, Tochigi, and Gunma, and considers the trade between these prefectures. Production forests were extracted as subcompartments where the expected revenues surpassed all costs, from planting to final harvest. To estimate harvesting costs, appropriate harvesting systems were determined according to each prefecture’s topographical features. The log markets and woody biomass power generation plants were assumed to be the destinations for timber and forest biomass resources. Annual availability from the Cut-To-Length (CTL) system, consisting of the use of harvesters and forwarders, accounted for 58 % of the total availability, even though the supply potential from CTL was only 15 %; this is because CTL is the most productive and least expensive harvesting system. Then, the effects of subsidies on availability are examined. Availability under an additional regeneration subsidy meets almost the entire current demand in this region. Furthermore, availability with a thinning subsidy can meet the forecasted future demand in this region, while availability with both thinning and additional regeneration subsidies can meet future demand in all prefectures analyzed in the present study. Thus, subsidies play an important role in the profitability of forestry operations as well as the supply of timber and forest biomass resources in Japan.  相似文献   

6.
This study evaluated the potential effectiveness of future carbon reserve scenarios, where U.S. forest landowners would hypothetically be paid to sequester carbon on their timberland and forego timber harvests for 100 years. Scenarios featured direct payments to landowners of $0 (baseline), $5, $10, or $15 per metric ton of additional forest carbon sequestered on the set aside lands, with maximum annual expenditures of $3 billion. Results indicated that from 1513 to 6837 Tg (Teragrams) of additional carbon (as carbon dioxide equivalent, CO2e) would be sequestered on U.S. timberlands relative to the baseline case over the next 50 years (30–137 Tg CO2e annually). These projected amounts of sequestered carbon on timberlands take into account projected increases in timber removal and forest carbon losses on other timberlands (carbon leakage effects). Net effectiveness of carbon reserve scenarios in terms of overall net gain in timberland carbon stocks from 2010 to 2060 ranged from 0.29 tCO2e net carbon increase for a payment of $5/tCO2e to the landowner (71% leakage), to 0.15 tCO2e net carbon increase for a payment of $15/tCO2e to the landowner (85% leakage). A policy or program to buy carbon credits from landowners would need to discount additions to the carbon reserve by the estimated amount of leakage. In the scenarios evaluated, the timber set-asides reduced timberland area available for harvest up to 35% and available timber inventory up to 55%, relative to the baseline scenario over the next 50 years, resulting in projected changes in timber prices, harvest levels, and forest product revenues for the forest products sector.  相似文献   

7.
This study investigated timber supply from Finnish non-industrial private forests (NIPF) using the consistent Tobit model and nationwide micropanel survey data on timber sales of 1299 forest owners during 2004–2008. The effects of forest owners’ gender and length of land tenure on timber supply were studied in particular. Women sold one cubic meter per hectare and per year (about 30%) less than men did. Female owners sold less frequently, but larger quantities at a time than did male owners. Short-tenure (<5 years) owners’ harvests were only affected by price, owner's age, income, timber stock and forest acreage. A group with relatively high harvest levels was young, low-income new forest owners.  相似文献   

8.
Optimizing harvesting decisions has been a matter of concern in the forestry literature for centuries. However, in some tropical countries, growth models for fast-growing tree species have been developed only recently. Additionally, environmental services of forests gain importance and should be integrated in forest management decisions. We determine the impact of a joint production of timber and carbon sequestration on the optimal rotation of a fast-growing species in north-western Ecuador, comparing different optimization approaches and taking the latest developments of the Kyoto Protocol into account. We find that payments for carbon sequestration have substantial impact on the rotation length: in contrast to an optimum of 15 years when focusing on timber production only, joint production leads to a doubling of the rotation length, which means that timber harvest should be postponed until the end of the carbon project.  相似文献   

9.
The problem of multiple-use forestry arises because (1) a forest can be managed to provide a wide range of products and services, (2) the different uses are not perfectly compatible with each other, and (3) some products are not priced in markets and many of the services a forest provides have the characteristics of public goods. Examples of major forest products include, in addition to timber, edible berries, fungi, and hunting games. Forests also provide recreation opportunities and various environmental services (such as regulating local climate, reducing soil erosion, reducing pollutants in the atmosphere, regulating the global climate, providing habitats for wildlife, etc.). The outputs of nontimber goods in general depend on the quantity and structure of the forest, which can be changed by various forest management activities. However, a forest state most suitable for the production of one good is usually not optimal with respect to another good. Typically, there does not exist a set of management activities that simultaneously maximize the outputs of timber and all other goods.Another way to understand the conflicts between different uses is to view standing timber as an intermediate product of forestry investment, which is employed as an “input” for the production of timber products and nontimber goods. Thinking in this way, the conflicts arise partly because timber production and nontimber uses compete for the same input, and partly because of the differences in the “production technology” among different nontimber goods. A change in the standing timber may have positive impacts on some nontimber uses, but have negative effects on others. Because of the conflicts among different uses, it requires that both timber products and nontimber goods should be explicitly incorporated into forestry decision-making in order to achieve the greatest benefits to the forest owner and/or the public.Most of the economic analyses of multiple-use forestry decisions have explicitly or implicitly adopted the view that multiple-use should be achieved in individual stands. Each stand should be managed to produce an optimal mix of timber products and nontimber goods. Another view of multiple-use forestry is to manage each stand for a primary use, whereas multiple-use concerns are addressed by allocating different stands in a forest to different uses. A general argument in support of the primary-use view is that specialization makes for efficiency. The production of timber and nontimber goods is a joint process, however. Strictly speaking, one cannot separate timber production and the production of different nontimber goods. For example, managing a stand for timber production does not exclude the possibility of producing some nontimber goods in the stand. Since every stand usually produces more than one product, efficient multiple-use forestry requires that each stand should be managed for an optimal mix of timber and nontimber outputs. On the other hand, it may well be the case that the optimal multiple-use mix for a particular stand consists of a maximum output of one product. In this case the optimal multiple-use management decision would coincide with the optimal decision pertaining to a single use. In other words, it may be optimal to manage a particular stand for one primary use. Using the terminology of economics, primary-use may be efficient for stands in which the multiple-use production set is nonconvex. Recent research has explored several sources of nonconvexity in the multiple-use production set. However, there is no evidence supporting the argument that specialization is always more efficient than multiple-use management of individual stands. From an economics viewpoint, efficient primary-use is special cases of multiple-use stand management.A widely recognized limitation of multiple-use stand management is that, by considering each stand separately, one neglects the interdependence of nontimber benefits and ecological interactions among individual stands. The nontimber benefits of a stand depend on the output of nontimber goods from other stands. Likewise, the nontimber output from one stand affects the value of nontimber goods produced in the other stands. Ecological interactions among individual stands imply that the output of nontimber goods from two stands in a forest differs from the sum of the outputs from two isolated stands. These interdependence and interactions imply that the relationship between the nontimber benefits of a stand and the stand age (or standing timber stock) cannot be unambiguously determined - it depends on the flow of nontimber goods produced in the surrounding stands. Therefore, it is improper to determine optimal decisions for the individual stands independently. In stead, efficient multiple-use forestry decision should be analyzed by considering all the stands in a forest simultaneously.Another serious limitation of multiple-use stand management is that each stand is treated as a homogenous management unit to be managed according to a uniform management regime. One implicitly assumes that the boundaries of each stand is exogenously given and will remain unchanged over time. This assumption imposes a restriction on the multiple-use production set, thereby creates inefficiency. As an example, consider a large stand with a nonconvex production set. It may be possible to eliminate nonconvexity in the production set and push the production possibility frontier outwards by dividing the stand into several parts and managing each part for a primary-use. It may also be efficient to combine two adjacent stands into one to be managed following a uniform regime, because of the presences of fixed management costs, and/or because the relationship between some nontimber outputs and stand area is not linear.In contrast to income from timber production, nontimber goods produced at different time points are not perfect substitutes. The rate at which a forest owner is willing to substitute a nontimber good produced at one time point for that produced at another time point changes with the outputs of the nontimber good at the two time points. In general cases, the nontimber goods produced at one time point cannot be consumed at another time point, and the marginal utility of a nontimber good decreases when its output increases. This provides a motivation for reducing the variation in the output of nontimber goods over time. An effective approach to coordinating nontimber outputs over time is to apply different management regimes to different parts of a stand, or apply the same regime to adjacent stands, which would change the boundaries of the stands. Preserving the existing stand boundaries would limit the possibility of evening out the nontimber outputs over time, and thereby lead to intertemporal inefficiency in multiple-use management.In previous studies of multiple-use forestry decisions the nontimber outputs or benefits are usually modeled as functions of stand age or standing timber stock. Future flows of nontimber goods or benefits are incorporated into a stand/forest harvest decision model to explore the implications of nontimber uses for optimal harvest decisions. While stand age and standing timber stock may have significant impacts on nontimber outputs, other forest state variables, e. g. the spatial distribution of stands of different ages/species, may be of great importance to the production of nontimber goods. Recognition of such forest state variables could change the relationship between timber production and nontimber outputs and therefore change the optimal forest management decisions.In summary, multiple-use forestry is not simply an extension of timber management with additional flows of benefits to be considered when evaluating alternative management regimes. Recognition of multiple uses of a forest leads to two fundamental changes of the forestry decision problem. First, the optimal intertemporal consumption of forestry income is no longer separable from forest management decisions. In general, the optimal intertemporal consumption of forestry income depends on future flows of nontimber goods, implying that the consumption-saving decision should be made simultaneously with the decision on the production of timber and nontimber goods over time. Secondly, it is no longer appropriate to optimize the management regime for each stand separately. The nontimber outputs from a forest depend on the age distribution of individual stands, and on a wide range of other forest state variables such as the spatial distribution of stands of different ages and tree-species composition. Ecological interactions and interdependence among stands imply that management regimes for different stands should be optimized simultaneously. In addition to changing rotation ages and harvest levels, efficient multiple-use forestry requires optimizing the spatial allocation of harvests, redefining the boundaries of stands, coordinating the choices of tree species in regeneration of harvested area and so on.The lack of rigorous production functions for nontimber goods imposes a severe restriction on attempts to perform comprehensive economic analyses of multiple-use forestry decisions. This restriction in itself is no justification for ignoring many of the key aspects of multiple-use forestry problem and modeling the problem as one of determining the optimal rotation age or optimal harvest level. It requires that economic models of multiple-use forestry should be developed with special consideration of the vague and imprecise information regarding the relationships between nontimber outputs and forest state variables.Peichen GongDepartment of Forest EconomicsSE-90183 UmeåSweden  相似文献   

10.
Ashgate Publishing Limited, Gower House, Croft Road, Aldershot, Hants GU11 3HR, England (www.ashgate.com). 498 p. £ 100.00. ISBN 0-7546-2237-1 (hardback).Being one volume in the series of the International Library of Environmental Economics and Policy (T. Tietenberg and W. Morrison, gen. eds.), this book is a collection of some of the most significant journal essays in forest economics and forest policy. In compiling this volume, Roger Sedjo did a great service to the forest economics profession.This volume includes twenty-five essays originally published between 1849 and 1996 in a dozen journals, and one chapter from the Third Assessment Report of the International Panel on Climate Change (IPCC, 2001) which addresses the biological sequestration of carbon in terrestrial ecosystems. These are organized into four parts: the harvest rotation issue, timber supply, multiple-use and non-timber outputs, and global issues. An introduction essay to this volume, written by the editor, provides an overview of the major issues in forest resource management and discusses some the most important contributions to the forest economics literature.The eleven essays in the first part of the book provide a rather complete coverage of the most important contributions to the literature on optimal rotation age, which is a fundamental issue in forest management and forestry investment. Four of the essays (Faustmann 1849, Ohlin 1921, Bentley and Teeguarden 1965, and Samuelson 1976) address the basic formulation and interpretation of the optimal rotation model. Four essays (Löfgren 1985, Newman, Gilbert and Hyde 1985, Reed 1984, and Brazee and Mendelsohn 1988) extend the basic rotation model to examine the rotation age decision in the presence of deterministic trends and uncertainty in timber yield and price, respectively. Based on the Faustamnn rotation model, Klemperer (1976) and Chang (1982) examine the impacts of taxation on forest value and on the optimal rotation age. Koskela (1989) provides a detailed analysis of the impacts of taxation on timber harvest decisions under price uncertainty. What I feel missing in this part is a comparative statics analysis examining the impacts of changing economic parameters on the optimal rotation age.Part II includes five essays on economic analysis of long-run timber supply. Clawson (1979) reviews the historical development of forest resource and forest utilization in the United States. Vaux (1973) examines the long-run potential supply of timber from forest plantations in California. Berck (1979) investigates the difference in harvesting behavior between private forest owners and public managers. Lyon (1981) and Lyon and Sedjo (1983) examine the optimal exploitation of old-growth natural forests and the transition to steady state. While these essays all focus on the long-run timber supply in the United States, the methods developed and used in these papers could be applied for any other region. The exploitation of old-growth natural forests and the long-term availability of timber have been without doubt two major concerns in the United States. In many parts of the world, however, concerns about timber supply in the short-run have also had great influences on the development of forest policy. It would have been appreciated if a couple of essays addressing the short-run supply of timber had been included.Part III contains three essays dealing with the problem of multiple-use forest management. Gregory (1955) develops an economic framework for multiple-use management based joint production theory. Hartman (1976) examines the multiple-use rotation age decision. Swallow, Parks and Wear (1990) investigate the problem of non-convexities involved in multiple-use rotation age decisions. The merits of these essays lie in that they use rather simple models to demonstrate the importance of incorporating non-timber benefits in forestry decisions and the complexities of the multiple-use problem. In his 1976 essay, Hartman points out that in many situations management practices applied to one stand affect the value of non-timber outputs derived from the adjacent stands; such interdependence needs to be incorporated into multiple-use decision analysis. I certainly would like to find in this volume one or two essays examining the impacts of stand interdependence on the optimal decision. Another important issue in multiple-use management, which is not covered in this volume either, is the valuation of non-market priced outputs and services. Yet I believe that this omission is well motivated, for there are two separate volumes in this series devoted to non-market valuation methods (R. T. Carson, ed. Direct Environmental Valuation Methods, Volumes I and II).The seven essays in Part IV deal with a set of forest economic and policy issues related to global warming and biodiversity conservation. Parks and Hardie (1995) examine the cost-effective subsidies to convert marginal agricultural land to forests for the purpose of carbon sequestration. Hoen and Solberg (1993) analyze the potential and cost-effectiveness of increasing carbon sequestration in existing forests by changing forestry practices. van Kooten, Binkley and Delcourt (1995) examine the effect of carbon taxes and subsidies on the optimal rotation age. The chapter from the Third Assessment Report of IPCC (2001) provides a comprehensive review of the literature on the ecological, environmental, social and economic aspects of carbon sequestration in terrestrial ecosystems. While forests and forest management could play an important role in mitigating climate change, increasing level of atmospheric dioxide and climate change would inevitably affect the productivity of forest ecosystems, thereby could have significant impacts on future timber growth, harvest and inventory as well as carbon storage in forest ecosystems. Joyce et al. (1995) present a framework for analyzing the potential effects of climate change on the forest sector. The remaining two essays in this part examine the costs and benefits of biodiversity preservation, respectively. Montgomery, Brown and Adams (1994) estimate the marginal cost of preserving the northern spotted owl. Simpson, Sedjo and Reid (1996) examine the expected value of the marginal species as an input to pharmaceuticals.The editor points out in the introduction chapter that there are many other important contributions that are not included in this volume, some of these are mentioned, others not. In addition to the few omissions noted earlier, several important economic and policy issues such as uneven-aged stand management, deforestation, international trade, sustainable forestry, forest recreation, wildlife management and so on are not discussed. Moreover, none of the journal essays published since 1997 is selected. That there are many other important contributions does not mean the essays included in this volume are less important, however. While each forest economist may present a different list of the most important papers, most (if not all) of the essays in this volume would appear on anyone's list. I strongly recommend this book for research scientists and graduate students of forest economics as an essential addition to their reference library.  相似文献   

11.
In Central Africa, creating forest roads and skid trails is one of the most costly and environmentally damaging operations for the forest's ecosystem. An optimized road network is essential for reducing construction costs and improving the sustainable management of timber resources. The location of landings is vital in the development of a future forest road network. In this study, a binary integer programming model similar to the uncapacitated facility location problem is formulated to optimize the locations of the landings. The model is applied to selective logging in Central Africa and tested on an annual logging zone in Southeast Cameroon. The results are compared to that of manual road planning, the currently used method.  相似文献   

12.
In this paper, a spatial-based economic model is proposed with the aim of estimating the most likely harvest cost of a forest block in relation to its particular morphological and operating features. This work, which is based on the classical stumpage price assessment method, presents an economic balance of a forest cut, attained by conducting a cost analysis of each logging phase of the different standard harvesting strategies. The study area is in the North-West of Italy, in the Mount Cotolivier forest compartment, in Oulx, Piedmont. The map of the stand structure, which is included in the Oulx Forest Management Plan, was used to locate blocks (areas considered homogeneous according to the stand structure and forest typology) where silvicultural cuts could be scheduled. The feasibility of the selected logging strategies was mapped considering six conditioning factors, of both a topological and a topographic nature. Their influence was weighted by means of a score assignation and integrated in a Multi-Criteria Decision Making procedure. The scores were mathematically combined to calculate a spatial dependent cost-function (Block Exploitation Aptitude, BEA) in which the suitability of each block to be harvested was mapped through a specific strategy. The obtained BEA was then used to estimate the most suitable productivity rate of the harvests of each block. The unitary costs of the strategies were estimated and then compared to find the most profitable one for each block.This model has proved to be effective in generating objective economic results concerning harvest cuts in productive stands in mountainous areas. The proposed methodology simultaneously takes into account different factors and generates feasibility scenarios, in the space domain, for the considered harvesting strategies. The proposed model represents a prototype on which an operational Decision Support System could be based to assist forest managers over the short-medium term.  相似文献   

13.
The year 2019 in Brazil was marked by environmental setbacks, which catalyzed the increase of illegal deforestation and fire rates in the Brazilian Amazon. In the Amazon region of Maranhão state, original forest cover diminished from 25 % (24,700 km2) in 2016 to 24 % (23,967 km2) in 2019, and 6,038 km2 of remaining forests were degraded by fires and/or illegal logging – processes related to high levels of violence against indigenous and rural communities. Almost half of all deforested areas in the region (36,060 km2) are considered a global restoration hotspot, however secondary vegetation remains unprotected and 8,294 km2 were cleared between 2014 and 2018. Due to uncontrolled deforestation and fragmentation, Maranhão has no more forest core areas (outside protected areas) with the minimum size to ensure sustainable forest management practices for timber production. New policies at the state level must promote old-growth and secondary forest conservation and restoration. However, the trends point to the opposite direction: the Ecological-Economic Zoning (ZEE) allows the reduction of forest protection and the State Forest Policy reinforces federal legislation setbacks. The Amazon region of Maranhão state has forest aptitude, and forest and agroforestry product chains would bring social and environmental benefits, making them the best opportunity for sustainable economic development in the region. Therefore, the forest must be re-planted for the benefit of people and nature.  相似文献   

14.
Participatory forestry has become the most accepted way of exploiting timber resources in tropical rain forests. This paper shows the links between participatory forestry, sustainable forest management and the continuing objective of reconciling conservation with commercial development in the province of Esmeraldas, one of the poorest and most rapidly deforested regions of South America. I describe and contextualize the evolving logging programme of a leading Ecuadorian wood-processing group to show that the decentralization of the development process, the recognition of local communities as legal entities in the management of natural resources, and the active involvement of profit-oriented firms in biodiversity conservation and poverty alleviation all contribute to the emergence of new alliances between the Ecuadorian government, the logging companies, conservation and human rights organizations, and local Black and indigenous communities. My central argument is that devolution in this context leads to conflictive interpretations of regulation. I end with a discussion of the multi-scalar nature of “forest governance”, and highlight the contribution it makes to our understanding of control, regulation and management in new contexts of privatization and decentralization.  相似文献   

15.
The recent rise of institutional timberland ownership has led to a significant change in the structure and conduct of the timber industry in the United States. In this study, we apply a two‐period harvest model to assess the timber harvesting behavior of various landowners at the stand level by utilizing USDA Forest Service Forest Inventory and Analysis data for nine southern states. Forest industry and institutional timberland owners were found to be more likely to conduct partial and final harvests than nonindustrial private forest landowners. Aggregately, Timberland Investment Management Organizations were found to be most, and timberland Real Estate Investment Trusts to be least, price‐responsive among ownership groups.  相似文献   

16.
This study presents a model that determines the effect of current and future payments for carbon sequestration, proportion of wood that sequesters carbon in long-lived product and landfills, and amount of carbon in the wood, on the optimal current forest harvest age. Increased current and future prices of carbon would lead to a longer and shorter harvest age, respectively. Higher current prices of carbon could increase the supply of carbon at a decreasing rate due to longer harvest ages. Moderate prices of carbon would encourage landowners to maintain standing timber. Policies focused then on stimulating landowners to hold timber on forestlands may not necessarily imply higher amounts of sequestered carbon. Increased future values of carbon could imply a reduction of the current supply of carbon.  相似文献   

17.
湖南省紧紧围绕国家林业局采伐管理改革具体部署:推进采伐分类管理,使采伐管理范围更加明确;编制森林经营方案,使限额管理更加科学;创新分配机制,使采伐指标分配更加公平;简化审批程序,使采伐指标申请更加便捷;加强监督管理,使采伐秩序更加规范。  相似文献   

18.
Agricultural sustainability practices make the best use of both nature's resources and available technology, and generally avoid those land use practices that lead to greater environmental stress. There are examples in some agro-ecosystems, however, where stress is vital to food quality and productivity. In the case of grape production, a limited amount of environmental stress actually leads to an increase in fruit quality, and with wine grapes, to improved wine quality. But when the stress exceeds an acceptable threshold, vine vigour declines and production and quality may be compromised. Using our experiences with environmental stress in grapes grown in the landscapes of Central and Eastern Washington, USA, we question how agricultural sustainability should consider environmental stress, and at what point management interventions contribute or detract from a sustainable system. Framed by the two French land-related terms ‘appellation’ and ‘terroir’, we discuss agricultural sustainability for grape cultivation in an arid climate.  相似文献   

19.
Selective logging (SL) contributes nearly 15 percent of the global timber needs. Considering its role in sustainable timber production, biodiversity conservation and forest carbon enhancement, assessment of SL policies and practices is crucial. This paper assesses the policies and practices of SL in natural production forests of the Tarai region of Nepal and Queensland Australia to explore the key differences in such policies and practices and their possible implications in achieving sustainable forest management objectives. The primary methods applied in the study were review and synthesis of key policy documents and qualitative analysis of the information gathered from key informant interviews and stakeholders’ workshop. Altogether, 53 respondents from a wide range of stakeholder groups (government organizations-15, non-government organizations/networks-15, private sector including the individual landowners-13, local political leaders-3 and independent forest experts/scientists-7) were consulted. Findings suggest that: (1) frequent and inconsistent changes in policy provisions, lengthy administrative procedures and heavy engagement of state forest agencies in forest product harvesting and sales processes play key roles in sub-optimal forest production in Nepal, whereas lower dependency on forest-products, higher labour costs, lack of species-wise royalty rate and flexibility in selecting optional logs are the key factors for increased wastages of forest products in Queensland; (2) recovery and utilisation of the harvested forest product is better in Nepal but policy and practical considerations on biodiversity and environment are better in Queensland; and (3) Forest harvesting specific codes of practice, occupational health and safety standards, and their compliance mechanism of Queensland could be beneficial for Nepal to minimise operational harvesting risks and to attract professional harvesters that support promoting sustainable use and management of natural forests, as we found this aspect almost neglected in Nepal.  相似文献   

20.
采伐限额管理制度对农户抚育采伐行为的影响分析   总被引:3,自引:0,他引:3  
依据农户理性人假设和实际调研数据,深入地分析了森林采伐限额管理制度对农户抚育采伐行为的影响,研究结论认为:森林采伐限额管理制度不影响农户抚育采伐决策,农户抚育采伐决策主要受到抚育采伐技术规程、抚育采伐的木材生产成本和短小材和小径材市场价格的影响,在抚育采伐技术规程的严格约束下,农户往往会推迟抚育采伐的开始期,并在采伐木的选择上做出"砍中留大留小"的决策,这说明严格的抚育采伐技术规程并未达到提高森林质量、促进森林资源增长的政策设计初衷,政府需要对森林抚育采伐的技术规程进行调整。  相似文献   

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