论红松果材林的生态经济问题

本文全面主红松果材林生态系统的特点,划分了吉林省红松果材林的栽培区域。提出了红松果材林复合生态系统类型和红松果材林经营的技术问题。     

A forest optimisation model including carbon flows: Application to a forest in Norway

We analyse which management to choose in order to increase the carbon benefit from the 1.342 million ha forest area in Hedmark County, Norway, and the cost of doing this compared to traditional profit maximising behaviour. The model used in the analysis is a dynamic forest management optimisation model which includes the main carbon flows and benefits from the forest area: tree growth and mortality, litter accumulation, decomposition of dead wood and harvest residues, soil processes, end-use of wood products, and saved greenhouse gas emissions from using wood products instead of more energy intensive materials and fossil fuels.     

气候谈判、木材产品国际贸易及其关系研究现状

文中介绍气候谈判产生的背景、谈判机制设计、影响谈判进程的因素等方面研究现状, 分析贸易政策与环境、资源禀赋、汇率变动等对木材产品国际贸易的影响; 在此基础上, 讨论气候谈判与木材产品国际贸易之间的关系。现有研究文献表明:气候谈判通过关税直接对木材产品国际贸易产生影响, 通过非关税措施包括森林认证、进口产品检验检疫、森林碳汇等对全球木材产品国际贸易产生直接或间接影响。然而, 这些研究主要还是基于简单的逻辑推理, 对于涉林气候谈判影响木材产品国际贸易的机理并没有进行深入剖析, 更没有通过大样本实证检验涉林气候谈判对木材产品国际贸易的影响。     

Bioenergy from the forest sector: Economic potential and interactions with timber and forest products markets in Norway

Abstract

A partial equilibrium forest sector model which is augmented to include bioenergy was applied to project the use of bioenergy based on forest fuels and forest industry by-products in Norway for three different scenarios of the future prices of electricity and oil. The impacts on forestry and forest industries of the different energy price scenarios were also studied. The advantage of the suggested methodology is that it allows for assessments of the economic potential of bioenergy, taking into account the competition for raw materials, the specific heat demand of various regions, and interregional and international trade. Bioenergy will, according to this study, be fairly competitive in some market segments with the current price levels of electricity and oil, and only a minor increase (decrease) in energy (roundwood) prices would release substantially increased bioenergy production levels. Pulpwood prices of pine and non-coniferous species are projected to increase substantially when assuming increasing energy prices. Except for particleboard mills, production levels of forest industries appeared relatively insensitive to the energy price changes.     

The role of the wood mechanical industry in the Swedish forest industry cluster

The forest and forest products form one of the most important basis for the transfer to a bio-based economy in Sweden. About 75% of the area covered by forest in Sweden is used industrially to produce raw material for the wood-refining industries. Every year, this cluster uses 75 million m³ of roundwood and has an export value of €12 billion. This review paper is devoted to the wood mechanical industry, i.e. the industry which turns the forest into sawn timber, packaging, construction wood, furniture and interior fittings. The sawmills consume about half of the volume of softwood which is felled, and about two-thirds of the sawn timber go to export without any further refining within the country. Nevertheless, in spite of the relatively low degree of refinement in the sawmill and the fact that the sawmills in general over time have a very low profitability, they are responsible for 70–80% of the forest owners' profits on the sale of timber. An increased upgrading of the sawn timber within the country is desirable from a national economic viewpoint – increased employment opportunities, increased export income, etc. It should then in the first place be for products with a higher added value, such as furniture and fittings. Today, the refinement value is 15–20 times higher for products from joinery and furniture industries compared to that of the sawn timber, and the added value of the wood within the building industry is only about 1.5 times.     

巴西林业资源、林产品贸易特点及对我国的启示

从林业地位、森林资源和林产品贸易三个方面介绍了巴西林业的概况,并在分析巴西林产品贸易特点的基础上,总结出对我国林产品贸易的4点启示,即要拓宽国内外市场,保证供需;稳扎稳打步步为营,形成优势出口产品品牌;内外兼顾,完善本国对外贸易法规;防微杜渐,提高管理和科技水平。巴西是世界生物资源和森林资源最为丰富的国家之一,总结和借鉴巴西林产品贸易情况对推动和促进我国林产品贸易及林业产业发展具有重要意义。     

Analysis of the potential of small-scale enterprises of artisans and sawyers as instruments for sustainable forest management in Puerto Rico

Small-scale forest enterprises have been recognized as a potential instrument for sustainable development. In particular, the production of handicrafts is a major form of cultural expression and a significant source of income in several developing countries. In this study, we characterize the local handicraft sector in Puerto Rico to identify essential elements for fostering small-scale forest enterprises. Artisans and sawyers were home-based microenterprises that harvested, processed, and traded a wide variety of local forest products, including 125 types of wood and several non-wood forest products. Nonetheless, severe competition from cheaper imported crafts, low demand, and high product variability hamper the development of the local handicraft sector. Despite globalization, sawyers and artisans in Puerto Rico, as part of the U.S., have access to the largest markets of tropical woods and home accessories in the world. But, to participate in these markets, they must increase competitiveness. Lack of institutional effectiveness is a major constraint for the success of the artisan development program in Puerto Rico. Therefore, cooperation and linkages between all support organizations, including government agencies, non-governmental organizations, and associations of artisans, need to be enhanced to provide effective technical assistance, marketing, and financial services to artisans.     

The changing administration and role of forestry in the economy of Vietnam

This paper reviews the changing forestry policies in Vietnam from the 1980s to the present. The role of forestry in the economy, developments in forest industries, government programs to encourage plantation establishment, and trade progress are examined. It is concluded that while there is a shortage of timber, log prices to growers are low due to high markups along the supply chain. Government programs such as the Five Million Hectares forestry program will lead to major supply increases in the future, but improvements in timber marketing will remain critical. While forestry exports from Vietnam have increased in the last decade, this has been based mainly on traditional handicrafts. Small enterprise size and lack of advanced technology limit export competitiveness.     

韩国山林组合发展及启示

在林权制度改革后,我国林业小规模经营与市场间的矛盾渐渐显现出来,林业专业合作社可以解决小生产与大市场连接的交易费用和风险成本高的问题。在设立以来的50多年间,韩国山林组合对韩国林业发展起到重要作用。文中介绍了韩国森林资源、木材供需情况、森林公益价值等林业基本概况以及山林组合的发展历程,分析了山林组合在韩国林业发展过程中的作用。韩国与我国互为邻国,韩国山林组合的发展对我国发展林业专业合作社具有一定的借鉴意义。     

Extreme events and climate change: the post-disaster dynamics of forest fires and forest storms in Sweden

How are extreme events understood in the forest sector? What are the implications of forest professionals' understandings and evaluations of extreme events? These questions are central to this study, which analyses the handling of the largest forest storm and the largest forest fire in modern Swedish history. The theoretical approach is that of risk governance in practice, which stresses that understanding the framings, practices and strategies used by members of professional organizations is pivotal for how disasters are managed. Two interview studies have been conducted with forest professionals involved in the two cases. The analysis shows that there were fundamentally different understandings of the two events and their implications for forestry practice. The storm was seen as an unavoidable natural disaster, but the consequences of future storms were considered possible to mitigate through changed forest practices. The forest fire, on the other hand, was conceptualized as a partly natural and partly man-made disaster, and forestry was seen as having very limited possibilities to reduce the likelihood as well as the consequences of similar events. The different understandings had significant implications for the post-disaster dynamics and for which management practices that were developed. Thus, understanding how extreme events are perceived is crucial to understanding which management practices that emerge in their wake, a topic of growing relevance because climate change is predicted to increase the frequency of forest fires and storms.     

Multiple-use forest management in consideration of climate change and the interests of stakeholder groups

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.     

Proportion of above-ground biomass in commercial logs and residues following the harvest of five commercial forest species in Australia

A significant factor influencing the contribution of wood products to carbon (C) storage is the proportion of above-ground tree biomass (AGB) recovered in commercial logs at harvest. This study examined the proportion of AGB in logs and residues at the harvest of radiata pine, cypress pine, blackbutt, spotted gum and messmate. Messmate and spotted gum had the highest variation in stem diameter and height. The average AGB ranged from 2000 to 3000 kg for the hardwoods and 220–1000 kg for the softwoods. Blackbutt had the overall lowest proportion of AGB recovered in commercial logs (45.5%) and radiata pine the highest (65%). The proportion of AGB in the bark of the hardwoods was significantly lower than in the softwoods. The proportion of the AGB in forest residues following harvest ranged from 30 to 55% depending on the species.The proportion of AGB recovered in high quality commercial logs ranged from 15% for spotted gum to 63% for radiata pine. The differences were due to the natural characteristics of the selected species and variations in regional market availability. The highest retention rates of AGB in high quality hardwood commercial logs were obtained for trees with DBH between 500 and 600 mm (messmate and blackbutt) and greater than 600 mm for spotted gum.The mean moisture content of the wood of the different species ranged from 35 to 50%. Messmate and radiata pine logs had the highest moisture content (48 and 50%, respectively).The C concentration of blackbutt, radiata pine and cypress pine was slightly higher than 50%. The softwoods had significantly higher C concentration than the hardwoods. The C concentration between positions (cross-section, sapwood and heartwood) also varied for the different species.The highest proportion of the above-ground C was in the debarked log for all species with the exception of blackbutt.The cellulose concentration of the wood ranged from 56 to 64% for hardwoods and 40–52% for the two softwoods. The lignin concentration of the wood ranged from 16 to 19% for the hardwoods and 25–35% for the two softwoods. The hardwood species could not be distinguished from one another based on the cellulose, hemicellulose and lignin concentration, but within the softwood species, cypress pine and radiata pine formed separate clusters.     

Soil carbon stock assessment in the tropical dry deciduous forest of the Sathanur reserve forest of Eastern Ghats,India

Climate change and carbon mitigation through forest ecosystems are some of the important topics in global perspective. Tropical dry forests are one of the most widely distributed ecosystems in tropics, which remain neglected in research. The soil organic carbon (SOC) stock was quantified on a large scale (30 1-ha plots) in the dry deciduous forest of the Sathanur reserve forest of Eastern Ghats. The SOC stock ranged from 16.92 to 44.65 Mg/ha with a mean value of 28.26 ± 1.35 Mg/ha. SOC exhibited a negative trend with an increase in soil depth. A significant positive correlation was obtained between SOC stocks and vegetation characteristics viz. tree density, shrub basal area, and herb species richness, while a significant negative correlation was observed with bulk density. The variation in SOC stock among the plots obtained in the present study could be due to differences in tree abundance, herb species richness, shrub basal area, soil pH, soil bulk density, soil texture etc. The present study generates a large-scale baseline data of dry deciduous forest SOC stock, which would facilitate SOC stock assessment at the national level as well as to understand its contribution on a global scale.     

Impact Assessment of Climate Change on Forestry Development in China

Forestry and forest ecosystem are highly sensitive to climate change.At present,studies about the responses of forests to climate change in China are more focused on physical influences of climate change.This paper firstly divided the key impact factors of climate change on forest and forestry developing into direct factors and indirect factors,and then made an assessment on climate change affecting future forestry development from the aspect of forest products and ecological services.On this basis,the adap...     

天水市国有林区森林资源变化分析

通过对天水市1979、1989和1996年进行的3次森林资源调查结果的分析，掌握和了解该地区森林资源现状和消长规律，以及造成林分、经济林、森林覆盖率等下降的原因，并据此提出了保护森林生态系统、提高林分质量的措施和对策，对实施天然林保护、恢复和重建天水主森林生态环境具有指导意义。     

湖南林业碳汇发展机遇

通过对国家政策、碳汇交易等内容分析了林业碳汇发展的机遇和挑战,并提出了湖南林业碳汇发展的建议。     

Role of homestead forests in household economy and factors affecting forest production: a case study in southwest Bangladesh

Empirical information regarding the role of homestead forests in household economy is essential in understanding the importance of these resources. Identification of the factors that affect homestead forest production and understanding forest owners' attitudes toward key forest management issues have great significance in making appropriate policy responses to manage these resources on a sustainable basis. In Bangladesh, homestead forests are claimed to play an important economic role in rural livelihoods, but no reliable quantitative information exists. This study was undertaken to investigate the role of homestead forests in the household economy, examine if forest production and income vary across landholding size classes, to explore the relationships of homestead forest production with species richness, education level, and household size, and to assess the attitude of homestead forest owners toward key forest management issues. Results show that homestead forests contribute 15.9% of the household income and generate 51.4 man-days of employment per household per year. Production of homestead forests significantly varies across landholding size classes. It was observed that forest production depends significantly on species richness of homestead forests and the education level of forest owners. However, no such relationship was found between forest production and household size. The study revealed that farming families depend more on forest income than nonfarming families. Attitudes of forest owners toward key forest management issues differ significantly across landholding size classes. For example, although the majority of the forest owners prefer fruit species to timber species, the percentage of respondents decreased as the landholding size class increased, while the opposite trend was observed for timber species. The findings of this study suggest that diversification of forests and extension of education amongst forest owners would improve forest production. Furthermore, forest policy should address the concerns of the forest owners in different landholding classes and focus on their specific requirements to enhance sustainable forest management.     

Non-timber forest products in rural Mali: a study of villager use

Malian Forest Service activities and policies have evolved since the beginning of colonialism under the assumption that forests and their products are the property of the government. Today the importance of involving local people in forest management is recognized. The purpose of this research was to determine the range of non-timber forest products local people use either for direct consumption or for income generation and to identify the trees/shrubs that yield these products in natural forests, fallow lands and crop fields. A gender analysis of the data was also conducted. The data were collected from face-to-face structured interviews using open-ended questions of 92 randomly sampled households in six Malian villages. One-half of the interviews were conducted with women and the other half were with men. The study identified 55 different non-timber forest products produced by 108 plant species. Almost all (99%) of the products identified are used for personal consumption, whereas 68% of the products are also used to generate income. Products such as firewood, leaves for sauces, shea nuts for oil/butter, seeds for condiments and nuts/seeds for soap are the most frequently mentioned products collected by women. Different categories of products like utensils/house materials, animal feed and construction materials (thatch, poles, mats) are the products most frequently collected by men. Ninety percent of the products collected are found in the natural forests; 63% are collected from trees on fallow lands and 51% from scattered trees in crop fields. Forest Service support of villagers using non-timber forest products would create an economic relationship between the forest and the local people. This is essential for the protection of the forest because people will safeguard their interests.     

Planning timber harvest of residual forest stands without compromising bird and small mammal communities in boreal landscapes

Numerous efforts have been invested in designing and configuring residual forest stands in Canadian boreal forest to preserve their overall biodiversity. Now that several landscapes have been partially logged, the next issue in forest management involves the planning of residual forest stand harvesting without compromising wildlife populations. Residual stands can be cut when adjacent regeneration reaches 3 m in height according to current regulations in several Canadian provinces (e.g., Québec, Ontario, Alberta, and British-Columbia). However, little is known on whether such regenerating habitat (RE-3m) can maintain wildlife communities similar to those found in unharvested mature forest (CO). We estimated the relative abundance of small mammals and forest birds in RE-3m and CO habitats and characterized landscape and stand structures. These variables were then compared between the two contrasting successional stages and were used to build habitat use models (HUMs) for 21 species. CO and RE-3m differed with regard to several landscape characteristics and stand structure variables as a result of logging. Snowshoe Hare, Northern Flicker, Alder Flycatcher, Ruby-crowned Kinglet, White-throated Sparrow and Magnolia Warbler were more abundant in RE-3m than CO, while Red-backed Vole, Brown Creeper and Golden-crowned Kinglet exhibited lower abundances in RE-3m. No significant differences in abundance were observed for the 12 other species. Species HUMs were highly significant and explained between 64.3 and 99.1% of the total variability in abundance. Following variance partitioning, stand structure variables accounted for most of the explained variability (54.2%) while landscape characteristics accounted for only 28.7%. No difference in species richness was observed but community evenness was greater in CO than RE-3m. Our results suggest that current regulations may threaten the maintenance of 3 out of 21 censused species for which abundances were significantly lower in regenerating 3 m tall stands. As stand structure explained a large amount of variability in abundance, it should be considered during timber harvest planning in both mature and regenerating stands. Until we know more on whether the current regulations are suitable for maintaining overall biodiversity, our results suggest that some mature forest stands should be maintained within managed landscapes for a complete logging rotation period.     

Comparing regional forest policy scenarios in terms of predicted suitable habitats for the Siberian flying squirrel (Pteromys volans)

Forecasting the potential impacts of forest policies on species of special conservation value is a prerequisite for safeguarding forest biodiversity. In this study, regional forest policy scenarios were compared in terms of predicted habitats suitable for the Siberian flying squirrel (Pteromys volans). To derive both patch- and landscape-scale models to predict species presence in a forest stand, species occurrence data from a systematic field survey covering the whole distribution area of the flying squirrel in Finland and Multi-Source National Forest Inventory data were combined. Then, the Finnish forestry model MELA and the derived occupancy models were applied to predict the quantity of suitable habitats for flying squirrels in three different 50-year policy scenarios. The results confirm that increasing the utilization of felling potential from the level of business-as-usual to the level stated as policy targets in regional forest programs decreases the amount of suitable habitat in the future. However, regional forest programs had a less drastic impact on habitats than maximum sustainable removal, except in two regions. It should be noted that the occupancy models seemed to fail on sites that experts deem to be most suitable for the species. Obviously, there are other factors than forest management affecting presence.