An integrated assessment approach to optimal forest bioenergy production for young Scots pine stands

Background: Bioenergy is re-shaping opportunities and imperatives of forest management. This study demonstrates,through a case study in Scots pine(Pinus sylvestris L.), how forest bioenergy policies affect stand management strategies.Methods: Optimization studies were examined for 15 Scots pine stands of different initial stand densities, site types, and temperature sum regions in Finland. Stand development was model ed using the Pipe Qual stand simulator coupled with the simulation-optimization tool Opti For Bioenergy to assess three forest bioenergy policies on energy wood harvest from early thinnings.Results: The optimal solutions maximizing bare land value indicate that conventional forest management regimes remain optimal for sparse stands. Energy harvests occurred only when profitable, led to lower financial returns. A forest bioenergy policy which included compulsory energy wood harvesting was optimal for denser stands. At a higher interest rate(4 %), increasing energy wood price postponed energy wood harvesting. In addition, our results show that early thinning somewhat reduced wood quality for stands in fertile sites. For less fertile sites, the changes were insignificant.Conclusions: A constraint of profitable energy wood harvest is not rational. It is optimal to carry out the first thinning with a flexible forest bioenergy policy depending on stand density.     

Exploring adaptation to climate change in the forests of central Nova Scotia, Canada

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.     

北京落叶松人工林全林分模型研建

以北京森林资源一类调查中侧柏的数据为基础,以Rechards方程为模版,通过spss统计建模工具进行拟合,建立了包括落叶松的树高模型、立地指数、林分密度、断面积指数、全林收获模型、林分生长模型在内的全林分模型。林分生长模型保持了与收获模型的相容性,在此基础上利用林分生长模型,可根据某一时期的林分收获量预知未来某一时期的林分蓄积。通过检验证明,此北京落叶松人工林全林分的林分生长模型有很强的适用性,为有关林业部门确定最优密度指数、立地指数等因子来改善落叶松的经营方式提供了依据。     

Improving sustainability of value-added forest supply chain through coordinated production planning policy between forests and mills

Commonly-used sustained yield harvest policies ensure sustained supply of harvest timber volume over a planning horizon. However, implemented policies gradually decapitalize forest values over time that threatens the sustainability of ecosystem and wood industries. Different business units of a forest-product supply chain have different ways of valuing forestry resources, different supply and demand policies, and corresponding business policy models to implement them. The objective of this study was to evaluate ecological and economic impacts to participating business units of a supply chain when implementing different business policies. We constructed six business models in a linear programming framework and solved them using data from commercially-managed forests. Our empirical results showed that compared to a base model (Model 1; unilateral decision by forest business unit), the best model (Model 6; integrated harvest and production planning) reduced the median harvest volume and area by 25% (12–31%) and 24% (7–40%), respectively, but increased net revenue by 88% (6–218%) over a 150-year planning horizon. Hence, efficiency increased by 158% (20–373%) per unit of harvest area and 163% (23–364%) per unit of harvest volume. Furthermore, when the models were simulated using a hard constraint to preserve at least 20% of old-growth forest area, the revenue was least affected (15%; 11–19%) by Model 6 compared to Model 1 (26%; 14–45%). We conclude that vertically-integrated harvest policy that embeds forest values in the planning model reduces the gap between the business units, and enhances ecosystem conservation with the least fluctuation of harvest and revenue by period over a planning horizon.     

日本国有林经营管理特点

本文着重论述了日本国有林的发展阶段及其经营管理的5个特点和经验:(1)确定了发挥森林多种效益的战略指导思想;(2)健全法制,依法治林;(3)建立一套科学的森林计划体系;(4)有一个稳定的林业管理体制;(5)采取扶持政策。最后,对日本国有林今后的发展进行了展望。     

Adaptation of the regional forestry administration to national forest, climate change and rural development policies in Finland

This paper examines the process of adaptation of the regional forestry administration in Finland to cross-scale socio-ecological changes in national policies and in the forest ecosystem. Self-organisation and knowledge building are the key elements employed in this case study conducted in the Southern Ostrobothnia Forestry Centre to analyse how the knowledge claims and networks are created in order to implement wood energy development projects. The case study method and the theory of adaptive co-management are found to be useful in explaining and understanding policy implementation and outcomes at the regional and local levels. A wood energy project met the forest, climate change and rural development policy targets by facilitating the establishment of a small heating business producing renewable energy from young forest thinnings. The practical outputs at the local level were energy generation from a renewable source; an increase in the area of young forest management; and increased rural entrepreneurship and employment. The unintentional output was that a new wood market arose. As a result of the case study, a two-level network has been introduced as an adaptive policy implementation practice.     

Modeling forest harvesting effects on landscape pattern in the Northwest Wisconsin Pine Barrens

Forest management shapes landscape patterns, and these patterns often differ significantly from those typical for natural disturbance regimes. This may affect wildlife habitat and other aspects of ecosystem function. Our objective was to examine the effects of different forest management decisions on landscape pattern in a fire adapted ecosystem. We used a factorial design experiment in LANDIS (a forest landscape simulation model) to test the effects of: (a) cut unit size, (b) minimum harvest age and (c) target species for management. Our study area was the Pine Barrens of northwest Wisconsin, an area where fire suppression has caused a lack of large open areas important for wildlife. Our results show that all three management choices under investigation (cut unit size, minimum harvest age and target species for management) have strong effects on forest composition and landscape patterns. Cut unit size is the most important factor influencing landscape pattern, followed by target species for management (either jack pine or red pine) and then minimum harvest age. Open areas are more abundant, and their average size is larger, when cut units are larger, target species is jack pine, and minimum harvest age is lower. Such information can assist forest managers to relate stand level management decision to landscape patterns.     

Optimal management of uneven-aged Norway spruce stands

An optimization model is specified to analyze forest management without any restrictions on the forest management system. The data on forest growth comes from unique field experiments and is used to estimate a nonlinear transition matrix or size-structured model for Norway spruce. The objective function includes detailed harvesting cost specifications and the optimization problem is solved in its most general dynamic form. In optimal uneven-aged management, stand density is shown to be dominated by limitations in natural regeneration. If the goal is volume maximization, even-aged management with artificial regeneration (and thinnings from above) is superior to uneven-aged management. After including regeneration and harvesting costs, the interest rate, and the price differential between saw timber and pulpwood, uneven-aged management becomes superior to even-aged management. However, in the short term the superiority is conditional on the initial stand state.     

Transformation of even-aged European beech (Fagus sylvatica L.) to uneven-aged management under changing growth conditions caused by climate change

Transformation from even-aged to uneven-aged forest management is currently taking place throughout Europe. Climate change is, however, expected to change growth conditions—possibly quite radically. Using a deterministic approach, it was the objective of this study to investigate the influence of such changes on optimal transformation strategies for an even-aged stand of European Beech in Denmark. For a range of growth change scenarios, represented by changes in site index, optimal harvest policies were determined using a matrix modelling approach and a differential evolution algorithm. Transition probabilities were updated continuously based on stand level variables and the transition matrix was thus dynamic. With optimal transformation policies, stand development followed similar pathways during the transformation phase irrespective of climate change scenario. Optimal transformation policies were thus robust, suggesting that a good policy would work well under different outcomes of climate change, i.e., acting under erroneous assumptions about change would not lead to major economic loss. For the chosen case stand, the net present value (NPV) of the transformation phase (first 100 years) contributed 80–90 % of the total expectation value at a 2 % discount rate. To assess the robustness of the optimisation procedure and understand the nature of the response surface, 100 replications per scenario were carried out. Variation between replications peaked during the later stages of the transformation phase indicating several pathways for transformation, which were characterised by almost identical levels of profitability.     

分层序列法在林分收获调整中的应用(英文)

分层序列法是一种多目标决策方法，本文将其用于山西省管涔山森林经营局千秋沟林场落叶松经营类型的森林收获调整．结果表明：使用该法，决策者可将对不同目标的要求落实到合理的水平上；该法求解简单，是进行森林收获调整有力的数学工具     

Determinants of private forest management decisions: A study on West Virginia NIPF landowners

The availability of timber in the United States depends largely on forest management and investment decisions of nonindustrial private forest landowners since they hold the largest share of forest land in the nation. Since NIPF landowners are so diverse, there is a need to better understand the determinants of their decisions so that policies could be in place to motivate them. A survey was carried out in 2005 to the nonindustrial private forest landowners of West Virginia to examine the factors affecting their forest management decisions. The study looked at four categories of decisions related to forest management: timber harvest, silvicultural activities (i.e., tree planting, herbicide application, fertilization, thinning, grapevine control, and timber stand improvement), property management activities (i.e., road construction, road maintenance, surveying/boundary maintenance, and access control), and wildlife habitat management and recreation improvement activities. Four models were developed to examine factors affecting each category of forest management activity. The results showed that landowner, ownership, and management characteristics of NIPF landowners are associated with their forest management decisions. Specifically, age, education, profession, income, ownership size, period of forestland acquisition, distance of the forestland to the place of residence, whether the forestland was purchased or acquired through inheritance or as a gift, primary objective of forestland ownership, and presence of a written forest management plan were found to be significant determinants for at least one of the categories of forest management activities. The models explained 25%, 27%, 31%, and 24% of the variation in timber harvesting, silvicultural activities, property management activities, and wildlife habitat management and recreation improvement activities, respectively. Understanding the underlying factors influencing forest management decisions of this diverse group of forest landowners could form the basis for developing, modifying and targeting policy instruments to motivate NIPF landowners in forest management.     

A Model for comparing reduced impact logging with conventional logging for an Eastern Amazonian Forest

Using data from a logging experiment in the eastern Brazilian Amazon region, we develop a matrix growth and yield model that captures the dynamic effects of harvest system choice on forest structure and composition. Multinomial logistic regression is used to estimate the growth transition parameters for a 10-year time step, while a Poisson regression model is used to estimate recruitment parameters. The model is designed to be easily integrated with an economic model of decisionmaking to perform tropical forest policy analysis. The model is used to compare the long-run structure and composition of a stand arising from the choice of implementing either conventional logging techniques or more carefully planned and executed reduced-impact logging (RIL) techniques, contrasted against a baseline projection of an unlogged forest. Results from “log and leave” scenarios show that a stand logged according to Brazilian management requirements will require well over 120 years to recover its initial commercial volume, regardless of logging technique employed. Implementing RIL, however, accelerates this recovery. Scenarios imposing a 40-year cutting cycle raise the possibility of sustainable harvest volumes, although at significantly lower levels than is implied by current regulations. Meeting current Brazilian forest policy goals may require an increase in the planned total area of permanent production forest or the widespread adoption of silvicultural practices that increase stand recovery and volume accumulation rates after RIL harvests.     

吉安林区商品林业经营政策的研究

作为南方重点林区，吉安林区的林林培育目标、资产运作、采伐政策、经营体制、行业管理、税费政策、林业投入等方面与市场经济的要求具有明显的滞后性和不适应性，同时也反映出林业行业的弱质性。要发展商品林业，其经营政策要作相应调整，政府应调整林业税费政策，建立生态补偿机制，理顺林业外部关系；林业系统要加快经营机制改革，规范资源流转，改革采伐政策等。     

论我国东北林区森林可持续经营

东北林区是我国的主要林区之一,区域森林资源表现出森林面积增大、森林覆盖率提高,森林蓄积量减少、森林质量下降,幼中龄林比重大、森林抚育滞后的态势。文章从社会对森林经营认识偏差、森林经营的经济驱动力的不平衡、现行法律和技术的缺陷、现行利用和保护政策的制约,以及现行管理机制的不完善等方面详细剖析了制约我国东北林区森林经营的深层次原因,有针对性地提出了加强可持续森林经营理念、实行国有林区森林管理和森林经营分离、实施对森林经营财税扶持政策、活化森林经营市场、加强森林经营基础性投资、理清部门职能、实施优质高效林培育工程等切合实际易于操作的具体思路和措施,以期促进东北林区的森林可持续经营。     

六盘山水源林林分目标层次结构研究

为适应六盘山水源林可持续经营实践的需求,利用六盘山林业局120个森林连续清查固定样地调查资料,分析了林分郁闭度对林下灌木、草本植物生长影响的规律,建立了适用于当地的数学模型,提出了该区水源林林分的目标层次结构。结果表明:1)该区水源林林分郁闭度影响林下植被的生长,林下灌木层、草本层盖度随林分郁闭度升高而降低;2)该林区水源林林分郁闭度保持在0.5～0.8之间时能够形成明显的乔灌草层次结构,有利于实现水源林经营的生态功能和经济功能的协调;3)该区水源林林分的目标层次结构为,林分郁闭度0.5～0.8,灌木层盖度35%～46%,草本层盖度35%～46%。研究结果可为该区水源林结构调整提供依据。     

日本落叶松人工林生长预测的全林分模型研究

以长岭岗林场日本落叶松人工林中的固定样地以及临时样地调查数据为基础，从模型间的相容性出发，建立了包含立地指数SI、林分密度SDI、林分断面积生长模型、树高曲线动态模型和林分收获模型的全林分模型系统，着重探讨了用Korf方程构造林分断面积生长模型时有关参数与SI和SDI的关系。     

Modelling the Growth and Management of Mixed Uneven-aged Maritime Pine - Broadleaved Species Forests in Galicia,North-western Spain

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.     

近自然森林经营是提高我国森林质量的可行途径

尽管我国森林资源数量位居世界前列,但存在着森林质量较低、人工林树种单一等问题。由于继续增加森林面积的潜力有限,我国发展森林资源的重点应该从面积的增加转移到质量的提高上来。起源于德国的近自然林业理论,体现了"天人合一"的哲学思想,强调人与自然的和谐相处,符合当今世界的发展潮流。用它来指导我国的森林经营实践,可以兼顾森林三大效益,平衡林业利益分配,有利于提高森林整体质量。应该调整和改进我国现有的森林经营模式,对天然林实施择伐经营和结构调控,对人工林进行近自然化改造,从而不断提高森林质量,逐步实现森林资源的可持续发展。     

国有森工企业组织结构影响因素的AHP分析

随着市场经济体系的逐步完善,沿袭多年的国有森工企业组织结构已跟不上时代的发展,改革势在必行。本文通过对吉林、黑龙江国有林区几个典型林业局的实际调研,采用层次分析法（AHP）对其组织结构的影响因素进行了定性和定量分析。结果表明,天保工程禁伐政策、国有林生态优先发展政策、企业管理水平是影响国有森工企业组织结构的关键因素。根据分析结果,提出了国有森工企业组织结构改革的政策与建议。     

Differences in forest management practices in Primorsky Krai: Case study of certified and non-certified by Forest Stewardship Council forest concessions

The Forest Stewardship Council (FSC) aims to promote environmentally responsible forest management globally. However, quantifiable evidence of effects of FSC on forest management practices is lacking. FSC has been present in the Russian forestry arena for over 20 years. In this case study, we compare ecological indicators of forest management in FSC-certified and non-certified companies in Primorsky Krai of the Russian Far East. Those indicators include percent of forest cover loss and gain on forest concessions managed by three certified and three non-certified companies. We also interview a range of stakeholders involved with forest management or in forest policy planning in Russia to provide context for this case study. Results indicate no difference between certified and non-certified companies with regard to forest cover loss from 2008 to 2015 or forest cover gain from 2000 to 2012. Stakeholder interviews reveal that while forest certification is viewed positively and considered an efficient mechanism to improve forest management, the stakeholders doubt its ability to stimulate quantifiable changes in forest management practices in Russia and the Far East specifically. We focus on Primorsky Krai because of its unique geographic location, where its neighbors China and Japan significantly influence Primorsky Krai’s export market.