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1.
Previous studies have reported significant gains from adopting the adaptive harvest strategy under conditions of timber price uncertainty. For the final harvest decision in even-aged stand management, the adaptive strategy typically means that a stand is harvested when the timber price is sufficiently high, whereas low prices are avoided by postponing the harvest. Such a harvest behavior may have significant impacts on the future price process, which in turn affects the landowner's profits. Moreover, it would certainly affect the timber-based industry and consumers. This paper assesses these impacts in a hypothetical timber market, using the Faustmann rule (FR) as a benchmark. The results show that changing from the FR to the reservation price strategy (RPS) reduces the supply of timber, thereby pushes up the price level. The RPS significantly reduces the short-run random variation of timber price. In the long run, both the mean and the variance of the timber price tend to stabilize. Depending on the anticipated price variation underlying the RPS, the expected timber price may be close to, or much higher than, the benchmark level, and the variance of price can be very large or very small. The welfare effect of the RPS is small if the anticipated variance of timber price used to optimize the RPS is small. If the anticipated variance of price is large, then the RSP leads to significant increase in the landowners’ profits and at the same time reduces the consumer surplus by a much larger amount.  相似文献   

2.
This paper presents an efficient and flexible approach of determining optimal thinning strategies for mixed-species stands with stochastic timber prices. The approach aims to determine the optimal stock of each species to be maintained in the stand conditional on the observed stand state and timber prices, whereas thinning intensity is given by the difference between the existing and the optimal stocks. For demonstration purpose, the approach is applied to determine the optimal thinning strategies for an example stand of Scots pine (Pinus Sylvestris L.) and Norway spruce (Picea abies L. Karst.) in northern Sweden. The optimal stock of each species is formulated as a parametric function of stand age and stumpage prices of the respective species. A reservation price function is constructed to determine the optimal time of clearcut based on the observed stand state and timber prices. The parameters of the optimal stock-level and reservation price functions are determined by maximizing the expected present value of the stand. The results indicate that using the optimal stock-level function approach can significantly improve the thinning decisions for mixed species stand with stochastic timber prices.  相似文献   

3.
Mangroves have been systematically exploited in Indonesia since 1800, especially for the development of brackish water shrimp aquaculture (called ‘tambak’) and for timber harvesting. By the end of the 1960s, Indonesia is estimated to have lost more than 200,000 ha of its mangroves mostly in Java and Sumatra. The rate of mangrove loss started to dramatically increase in the 1970 when exploitation shifted to new areas outside Java, particularly in Kalimantan and Sulawesi, encouraged by government policies to boost timber production, followed by policies to expand tambak in 1980s and large scale tambak development triggered by increased shrimp price during Asian financial crisis in 1997. The result has been the loss of nearly 800,000 ha of mangroves in only 30 years, mostly now in the form of low productivity or abandoned tambaks. In recent years, timber harvesting activities in Indonesia's mangroves appear to have become more sustainable. Our analysis suggests that aquaculture will continue as the main driver of change in mangrove ecosystems in Indonesia followed by palm oil plantation. Failure to deal with the current low productivity of shrimp aquaculture in many parts of Indonesia will force shrimp producers to clear an estimated 600,000 ha more mangroves to make way for shrimp farms over the next two decades. However, with improvements in brackish water aquaculture productivity, halting palm oil concession to utilise mangroves, along with maintaining other mangrove use pressures at moderate levels, the net loss of mangroves in the next two decades could be reduced to around 23,000 ha.  相似文献   

4.
Integration of trees on upland farms in the Philippines has been slower than expected and desirable from an environmental perspective. Our economic and risk analysis points to current policies as part of the problem. The study compares three domesticated indigenous timber trees (Shorea contorta V., Pterocarpus indicus J., and Vitex parviflora W.) intercropped with maize against a benchmark of the widely used exotic mahogany (Swietenia macrophylla K.). We used a biophysical simulation model (WaNuLCAS 3.1) to represent interaction between trees and crops for a fundamental level of water, nutrient and light capture as the basis for production functions. External conditions affecting systems profitability were accounted for in the Policy Analysis Matrix (PAM). Elements of risk were introduced through Monte Carlo simulation. Study results revealed that from a farmer’s perspective intercropping systems provide similar (within an uncertainty range of + or ? 10%) returns to monocropping scenarios. When net subsidies and taxes are accounted for, social profitability evaluations favour tree intercropping at high tree densities. The net effect of the current bias in price policies towards food production therefore refrains farmers from making decisions to integrate trees on farms; a decision that is actually in the national interest on economic grounds, even without consideration of positive environmental effects.  相似文献   

5.
We examine the intensity of harvesting decision by non-industrial landowners at the lowest price offer they deem acceptable, using a multiple bounded discrete choice stated preference approach that draws upon and connects two subfields of forestry, one identifying characteristics of landowners important to past harvesting or reforestation decisions, and another proposing how landowners evaluate price offers for forest harvesting decisions. Variables important to harvest intensity choices when the landowners find an acceptable price have only been considered for those landowners who actually have participated in harvesting markets, whereas here we examine the behavior of these individuals as well as those who are on the margin (i.e., have not harvested at prevailing current or past market prices). We show that harvest intensity depends critically on the extent of urbanization, indicated by the presence of structures on a parcel as well as forested tract size, along with landowner characteristics such as absenteeism and length of ownership. The results are useful for understanding the timber management behavior for a majority of landowners who may not harvest at prevailing prices, but may participate should prices reach a level acceptable to them, where this level is determined by individual preferences for standing timber resources.  相似文献   

6.
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   

7.
The price of timber stumpage is one of the few natural-resource rents that can be directly observed as a market price. Rules for optimal timber harvesting under uncertainty have been found to depend on whether the timber rent price is non-stationary or stationary. In this study we extend previous research by Hultkrantz (1995) that tested for unit-root with an exogenous break point in Swedish stumpage prices from 1909 to 1990, employing data up to 2012, hence for 104 years, and unit-root tests with endogenously selected break points. We find support for a structural level break at the end of WW2 and that non-stationarity can be rejected. We show that this is a robust conclusion. There is thus no sign of a new break in the extended recent time period and no signal of a secular increase of timber resource scarcity.  相似文献   

8.
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   

9.
In deciding to keep or fell a forest stand given its age, the risk of loss of timber through wildfire is an important consideration. If trees also have value from sequestration of carbon, another effect of fire is the unplanned loss of stored carbon. Factors affecting the decision to keep or fell trees, and how much to spend on fire protection, are investigated using stochastic dynamic programming, using carbon sequestration in stands of mountain ash in Victoria as a case study. The effect of treating sawlogs as a permanent carbon sink after harvesting is explored.  相似文献   

10.
This paper examines the potential and the cost of promoting forest carbon sequestration through a tax/subsidy to land owners for reducing/increasing carbon storage in their forests. We use a partial equilibrium model based on intertemporal optimization to estimate the impacts of carbon price (the tax/subsidy rate) on timber harvest volume and price in different time periods and on the change of forest carbon stock over time. The results show that a higher carbon price would lead to higher forest carbon stocks. The tax/subsidy induced annual net carbon sequestration is declining over time. The net carbon sequestration during 2015–2050 would increase by 30.2 to 218.3 million tonnes of CO2, when carbon price increases from 170 SEK to 1428 SEK per tonne of CO2. The associated cost, in terms of reduced total benefits of timber and other non-timber goods, ranges from 80 SEK to 105.8 SEK per tonne of CO2. The change in carbon sequestration (as compared with the baseline case) beyond 2050 is small when carbon price is 680 SEK per tonne of CO2 or lower. With a carbon price of 1428 SEK per tonne of CO2, carbon sequestration will increase by 70 million tonnes of CO2 from the baseline level during 2050-2070, and by 64 million tonnes during 2070–2170.  相似文献   

11.
In applications of expected utility analysis, researchers are confronted with a choice among several utility functional forms. Subjective utility values and probability distributions for price and yield were elicited from Sri Lankan producers of minor export crops. Exponential quadratic and cubic utility functions were estimated. The choice of functional form was found to affect both the classification of risk attitudes and the prediction of harvesting strategy. The exponential function was the best predictor of harvesting strategy because it was the best predictor of mature harvesting. All three functions were equally poor predictors of premature harvesting.  相似文献   

12.
A solution is demonstrated to an infinite-horizon, discrete-time utility model describing the consumption and cutting behavior of a nonindustrial private landowner who is managing a multiple age-class forest and who values both consumption derived from harvesting the trees and amenity derived from the standing trees. A policy rule is derived to attain a normal forest from any initial age-class distribution. It is demonstrated that a noncyclical forest allowing a constant periodic harvest is typically not a normal forest. Therefore, an even-flow timber harvesting is not tied to the existence of a normal forest structure.  相似文献   

13.
Sequestering carbon in forest ecosystems is important for mitigating climate change. A major policy concern is whether forests should be left unharvested to avoid carbon dioxide (CO2) emissions and store carbon, or harvested to take advantage of potential carbon storage in post-harvest wood product sinks and removal of CO2 from the atmosphere by new growth. The issue is addressed in this paper by examining carbon rotation ages that consider commercial timber as well as carbon values. A discrete-time optimal rotation age model is developed that employs data on carbon fluxes stored in both living and dead biomass as opposed to carbon as a function of timber growth. Carbon is allocated to several ecosystem and post-harvest product pools that decay over time at different rates. In addition, the timing of carbon fluxes is taken into account by weighting future carbon fluxes as less important than current ones. Using simple formulae for determining optimal rotation ages, we find that: (1) Reducing the price of timber while increasing the price of carbon will increase rotation age, perhaps to infinity (stand remains unharvested). (2) An increase in the rate used to discount physical carbon generally reduces the rotation age, but not in all cases. (3) As a corollary, an increase in the price of carbon increases or reduces rotation age depending on the weight chosen to discount future carbon fluxes. (4) Site characteristics and the mix of species on the site affect conclusions (2) and (3). (5) A large variety of carbon offset credits from forestry activities could be justified, which makes it difficult to accept any.  相似文献   

14.
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   

15.
Negative carbon emissions options are required to meet long-term climate goals in many countries. One way to incentivise these options is by paying farmers for carbon sequestered by forests through an emissions trading scheme (ETS). New Zealand has a comprehensive ETS, which includes incentives for farmers to plant permanent exotic forests. This research uses an economy-wide model, a forestry model and land use change functions to measure the expected proportion of farmers with trees at harvesting age that will change land use from production to permanent forests in New Zealand from 2014 to 2050. We also estimate the impacts on carbon sequestration, the carbon price, gross emissions, GDP and welfare. When there is forestry land use change, the results indicate that the responsiveness of land owners to the carbon price has a measured impact on carbon sequestration. For example, under the fastest land use change scenario, carbon sequestration reaches 29.93 Mt CO2e by 2050 compared to 23.41 Mt CO2e in the no land use change scenario (a 28% increase). Even under the slowest land use change scenario, carbon sequestration is 25.89 Mt CO2e by 2050 (an 11% increase compared with no land use change). This is because, if foresters decide not to switch to permanent forests in 1 year, carbon prices and ultimately incentives to convert to permanent forests will be higher in future years.  相似文献   

16.
Timber prices in the area struck by a natural disaster such as a hurricane or pest infestation are known to drop sharply immediately following the disaster, only to recover after about a year or so. Previous research attributes the rapid recovery to shifts in supply and demand curves. Our analysis suggests the more probable explanation is rotation in the curves. Supply and demand shifts come into play in the second and third years as rebuilding from the hurricane begins in earnest, and as timber inventory is rebuilt in response to elevated price expectations. But for the period in which price recovery occurs, model simulations based on data for Hurricane Hugo indicate the major causal factors of the observed price dynamics are curve rotation and trade with the surrounding undamaged region. Inventory-based supply shifts, the previously-identified causal factor, play a minor role in the observed price dynamics. Getting the causal factors right is important for predicting the price effects of forest inventory shocks, and for proper measurement of their welfare effects.  相似文献   

17.
[目的]烟草种植替代是从源头控制烟草消费的最有效措施,但在我国还未全面实施。文章分析研究不同情境下烟草种植替代可能产生的综合效应,以期推动我国烟草种植替代的实施。[方法]基于2018年湖北省利川市11种作物的成本收益、化肥使用量等数据,利用情景分析法,结合环境风险指数法和综合评价法对烟草种植替代可能产生的综合效应进行分析。[结果](1)种植烟草高昂的人工成本使得其净利润为负,且在11种作物中最低,其现金收益仅高于粮食与油料作物,种植番茄或黄瓜的现金收益分别比烟草高7倍和6倍,烟草较高的价格可能是吸引农户种植的主要原因之一;(2)情景1种植烟草的氮肥使用环境风险较低,磷肥与钾肥使用的环境风险等级较高;情景2种植粮食作物可以减少化肥使用的环境风险,种植蔬菜等作物会增加化肥使用的环境风险;(3)在该文的3种情景中,粮食作物的固碳能力较强,经济作物的固碳能力较弱;种植烟草的固碳能力最弱,其综合效应仅优于油菜籽与烟草的组合,远低于种植蔬菜或烟草与蔬菜作物组合种植的综合效应。[结论]利川市可以选择番茄、黄瓜等蔬菜作物或是这些作物与烟草共同种植的方案来代替烟草种植,在履行《烟草控制框架公约》的同时能...  相似文献   

18.
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   

19.
Timber and lumber markets are linked and integrated through prices at several stages along timber supply chain. In this study, the degree of vertical integration and the presence of asymmetric price transmission are investigated for sawtimber and lumber products in the southern and western United States. The data utilized are quarterly stumpage price, delivered timber price, and lumber price of softwood between 1977 and 2011. Linear and threshold cointegration models are used for long-term price analyses, and symmetric and asymmetric error correction models are used for short-term price analyses. The integration in the early stage (i.e., stumpage/delivered timber price pair) is found to be stronger than that in the latter stage (i.e., delivered/lumber price pair). The South shows slightly stronger market cointegration than the West. Asymmetric price transmission is found along the timber supply chain. In the long term, prices are more responsive when the price margin is increased than decreased.  相似文献   

20.
以林农拥有的活立木为研究对象,利用2007—2017年浙江省1546宗活立木流转样本,采用多元线性回归实证分析了是否在林权交易中心交易对活立木流转价格存在影响。结果表明:关键解释变量是否在林权交易中心进行交易对活立木流转价格具有显著的正向影响;流转面积、单位面积蓄积、区域虚拟变量、坡度等对流转价格都产生一定程度的影响;流转期限对流转价格的影响不大。因此,需要加强对林权交易中心的宣传,降低相关的交易成本,从而吸引更多的小规模林农参与交易。  相似文献   

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