基于房室理论的湖南黄丰桥林场森林结构动态分析

根据湖南黄丰桥林场森林资源二类调查数据,应用房室理论。建立森林结构动态模型,模拟、分析黄丰桥林场森林结构中林种、地类因子动态变化状况;建议减小无立木林地及非林地数量,控制竹林增长速度,预计调整森林经营方案后,将实现林场长远规划预期目标。     

Farm Level Tree Planting in Pakistan: The Role of Farmers’ Perceptions and Attitudes

The low proportion of forested land and continuing degradation of existing forest cover are serious threats to the sustainability of forestry in Pakistan. Farm forestry has been identified as a feasible solution, particularly in the plain areas. Applying the Theory of Planned Behaviour in a survey of 124 farmers in Dera Ismail Khan district of Pakistan’s North West Frontier Province showed that farmers’ willingness to grow trees on their farms is a function of their attitudes towards the advantages and disadvantages of growing trees, their perception of the opinions of salient referents and factors that encourage and discourage farm level tree planting. Farmers viewed farm forestry as economically beneficial and environmentally friendly. Tree planting was perceived as increasing income, providing wood for fuel and furniture, controlling erosion and pollution and providing shade for humans and animals. Farmers saw hindrance in agricultural operations and the harbouring of insects, pests and diseases as negative impacts of tree planting; however, these were outweighed by their perceptions of positive impacts. Tree growing decisions of farmers were influenced by the opinions of family members, owners/tenants, fellow farmers and village elders. The factors that significantly predicted farm level tree planting were availability of barren land, lack of markets, lack of nurseries and damage caused by animals and humans. Farm forestry programmes are more likely to be successful if they acknowledge and address the factors which underlie farmers’ reasons for planting or not planting trees.     

小陇山龙门林场森林资源动态变化分析

依据甘肃省小陇山林业实验局龙门林场1994和2008年二类调查(森林资源规划设计调查)数据,从森林资源各类土地面积、蓄积量、组成结构等方面分析了该林场14年间森林资源消长变化规律,并对变化的原因进行了分析。结果表明:龙门林场有林地、宜林地、未成林地、苗圃地等地类面积呈增加趋势;灌木林地、疏林地、无林地等地类面积呈减少趋势;从蓄积量来看,活立木蓄积量持续上升,生长量大于消耗量。人工林的面积增长较快,以落叶松林为主,未成林造林地则为针叶、阔叶和针阔混交;从林龄结构上来看,中龄林增长较快。     

Rural livelihood benefits from participation in the taungya agroforestry system in Ondo State of Nigeria

This study examines the strategies and benefits of the taungya farming system to both the government and the rural economy in Nigeria. An interview survey was conducted in which data were collected from 115 randomly selected farmers in five villages in the Oluwa forest reserve, Ondo State, Nigeria. The study examines the extent of participation of rural dwellers in plantation development through taungya farming and the degree of success of this system as an afforestation method. The farmers were predominantly illiterate, within the age bracket of 35–54 years and with small farm holdings. Twenty nine percent relied totally on food from the forest reserve for their livelihood, while 71% also had farm holdings in free areas. Land within the reserve is allocated to farmers free of charge but compensation is paid to landlords on land from free areas. A statistically significant difference was detected in income from the two sources of farmland for the households and but not in the size of land allocated under taungya and free areas. About 184 farmers are involved in taungya annually, and 410 ha of Tectonia grandis has been established for the government of Ondo State.     

福山区国有福山林场改革发展的探索与思考

指出了福山区国有福山林场1949年建场,经营面积233.7 hm 2,为公益型林场,存在着森林资源结构不合理,林地生产力低等问题。为了改变这一现状,近年来,国有福山林场立足林场实际,探索思考了国有福山林场改革发展,完善改革发展经验,坚持以资源保护为核心,大力规划发展林场造林绿化、森林防火、森林抚育、病虫害防治等重点工作,提升国有福山林场森林资源结构质量水平,促进国有福山林场又好又快发展,实现森林多种功能和效益的发挥。     

Small-Scale Mehedi (<Emphasis Type="Italic">Lawsonia inermis</Emphasis> L.) Farming in the Central Bangladesh: A Promising NTFP-Based Rural Livelihood Outside the Forests

Throughout the world ornamentation of body with mehedi (Lawsonia inermis L.) leaf paste, with the trade name ‘henna body art’ is becoming increasingly popular. The worldwide increasing demand of mehedi leaf encourages many countries to adopt commercial farming of the plant. Farmers living in central Bangladesh recently commenced small-scale mehedi farming, primarily with the purpose of meeting national demand. A total of 182 farmers are engaged in mehedi farming and a study was conducted among 36 of them (a 20% random sample) to explore indigenous management techniques, marketing, livelihood potential and constraints of the enterprise. Farming was reported to be the major primary occupation of the study area. An average of 0.05 ha land of the respondents was used for mehedi cultivation, which constituted 16.7% of their average farm land. The farmers applied their own indigenous technology in every aspect of the farming, using branch cuttings as the only propagation material. The financial analysis indicated that mehedi farming is a profitable and attractive option for rural livelihoods [with an estimated net present value of Tk (Bangladeshi currency unit, 1 US $ = 68 Taka (as of May, 2009).) 179,500 for 0.1 ha plantation]. However, the enterprise faces several constraints, including absence of a nursery for supplying planting materials, storage and effective marketing facilities, available capital for investment, improved technology, and above all, government support. If the government extends cooperation by assisting farmers with training, technology, credit and market development, mehedi farming could become an important revenue-earning enterprise in the small-scale cottage sector of Bangladesh.     

Constraints for future cocoa production in Ghana

To address the growing global demand for cocoa, sustainable intensification of its production in West Africa is considered crucial. This paper analyzes the determinants of cocoa productivity and profitability by smallholder farmers in Ghana to provide insights into challenges for future cocoa farming, which will guide the formulation and prioritization of tailored policies to address them. A four-stage sampling technique was used to select a total of 731 cocoa farmers from various districts in all six cocoa growing regions in Ghana. Selected farmers were interviewed using a semi-structured questionnaire. The results show that cocoa productivity and profitability was very low with an average of 234 kg ha^?1 and Gh¢ 568 (ca. US$ 150) per ha, respectively. Farm management practices, namely control of capsid and black pod disease, fertilizer application and pruning, significantly (p < 0.05) influenced cocoa productivity. Capsid control and fertilizer application showed the highest impact on productivity. Farm size, however, had a negative impact, which implies that increase in farm size results in decreased smallholder cocoa productivity. Farmers should be encouraged to sustainably intensify farm management through controlling black pod disease and capsids, regular pruning and efficient application of fertilizer rather than focusing on excessive land expansion, which eventually hampers productivity and biodiversity.     

Forest villages: an agroforestry approach to rehabilitating forest land degraded by shifting cultivation in Thailand

The Forest village scheme was introduced by the Forest Industries Organisation (FIO) of Thailand in 1967 as an attempt to stop further spread of the fast increasing shifting cultivation and deforestation in the country. The underlying princple of the scheme is to relate reforestation with social welfare of the people involved. It is essentially a modification of the traditional taungya method of plantation establishment.The salient aspect of the scheme is to induce the shifting cultivators to settle down in villages where each family is given tenure over a plot of land to construct a house and develop a homegarden around it. The farmers are required to help establish and maintain forest plantations, in which they are permitted to raise agricultural crops during the first three years of its establishment. The farmers are also given free medical and educational facilities, and technical advice on crop and livestock husbandry. They can also earn cash rewards for successful plantation establishment.Although the scheme has not achieved its full target in terms of area covered and number of families settled, it is proving to be a successful method of luring people away from destructive shifting cultivation. The approach is applicable to other countries and regions with similar land-use problems and socio-cultural background.The paper also examines the constraints to the effective working of the scheme, provides some simple suggestions for improving its functioning and identies some of the issues that can easily be tackled by research.     

北京西山油松人工林结构特征研究

以西山试验林场近自然经营试点区建立的11块中龄油松人工林样地为依据,对油松林分的结构特点、表达模型和树种多样性格局进行了分析。结果表明：油松人工林林分平均密度为1069株／hm^2,平均胸径为13．7cm,平均高为8．6m,蓄积量为86．36m3／hm^2。应用正态分布、Weibull分布、对数正态分布、Gamma分布和Beta分布拟合直径和树高结构,发现正态分布拟合直径分布和树高分布效果最好,也符合人工林的林分结构规律;油松人工林层次结构简单,物种多样性较低,乔木层、灌木层和草本层的Shannon—wiener指数、均匀度指数分别为0．355、0．726、0．160和0．372、0．651、0．266;幼苗更新各高度级均以构树和栾树为主,他们分别占总体更新树种的72．2％和10．2％。     

森林经营方案编制方法研究--以临武县东山国有林场为例

根据临武县东山国有林场开展森林经营的需要,依据国家林业相关政策、森林经营方案编制技术规程,结合现有的森林资源现状及发展方向,分析了临武县东山国有林场森林经营环境,提出了林场森林经营方针、原则与经营目标,设计了林场森林发展阶段的主要经营措施,规划了林场森林多资源利用方案,以供在经理期内规划参考落实。     

Agroforestry potential of Dacryodes edulis in the oil palm-cassava belt of southeastern Nigeria

Between June 1993 and June 1994, 112 farmers in the oil palm (Elaeis guineensis)-cassava (Manihot esclentus) belt of southeastern Nigeria were interviewed to determine the status and agroforestry potential of Dacryodes edulis. Between 50% and 100% of respondents in different states within the belt owned D. edulis trees. On average, a farmer owned 9.3 trees, the largest number being 16, by farmers in Imo State. Twenty percent of farmers in the system rated D. edulis their best farm tree. It was present in all the farm niches: homegardens (51.4%), tree crop plots (20.7%) food crop plots (11.4%), secondary forest/fallow (14.2%) and virgin forest (2.5%). The tree is planted primarily for home consumption and sale to generate cash. At the current densities, on-farm D. edulis trees generally did not decrease yield of companion crops or trees. Except for ring weeding around the stem, D. edulis trees received little or no management attention. More than 50% of the trees produced 33 to 50 kg of fruit tree⁻¹ annually. This is valued at US $0.4 to 0.8 kg⁻¹. Farmers were willing to plant more D. edulis trees provided trees with traits such as less height for easy harvesting of fruits, larger fruit, more fruits, sweeter fruits and year round production of fruits were available. Possible agroforestry technologies into which D. edulis may fit include live fences, scattered trees in food crop fields, shade trees in tree crop plots and contour bund or hedgerow planting. Research is required to determine best tree accessions, canopy management strategies, optimum tree population and improved methods on post- harvest handling of fruits. This revised version was published online in June 2006 with corrections to the Cover Date.     

杉木人工林采伐作业生态环境影响经济评价的探讨

构建适合德化葛坑国有林场森林采伐作业生态环境影响经济评价指标体系,以林场杉木人工林为对象,依据实验小班长期、连续观测数据及国内外森林生态服务功能价值评估研究成果,利用最近资源清查资料、伐区设计资料及社会公共数据,估算了杉木人工林采伐作业对环境影响的经济价值量。当森林经理调查获得小班各林分因子及相应生态指标数据后,建立的森林生态环境影响经济评价指标体系,可以对森林采伐作业所造成的生态环境影响,从经济价值角度,给出一个评估值,为森林资源的合理利用及采伐提供科学参考依据,在林业其他生产经营项目上也具有推广应用价值。     

From farm forestry to farm and forestry in south-western France as a result of changes in a ‘house-centred’ social structure

The importance of the ecological functions of farm forests in France calls for a better understanding of the social systems influencing forest management. The traditional ‘house-centred system’ involved a sharing of activities in farm forestry between fathers and their sons. Retired farmers were traditionally managers of the forests while their sons dealt with farming activities. The evolution of this relationship since World War 2 has been investigated with an ethnologic approach in two villages in south-western France where the traditional ‘house-centred system’ constrains the social rules. This system has led to a lifetime status for fathers as head of the farm and of the household. Before WW2, sons played a secondary role in relation to their fathers who took strategic decisions. After WW2, sons became more involved in the forest work and decisions which led to a more frequent use of agricultural methods in forests. This created differences of opinion between fathers and sons, with the fathers considering their sons’ management too intensive. The social consequence was that the fathers felt that their role as forest managers and as head of the farm was reduced. In future, farm forest management might become more dependent on agricultural activities, with the traditional social systems losing importance.     

国有北岭山林场生态公益林碳储量和碳密度研究

研究以小班为基本研究单元,按起源分林龄对广东省肇庆市国有北岭山林场生态公益林碳储 量进行了研究。国有北岭山林场乔木林总碳储量为 278.0×106kg,其中生态公益林碳储量为 244.9×106kg。生态公益林中天然林在不同林龄间的林分间平均碳密度不存在显著差异,范围（25.24±1.02）~ （28.01±1.69）×103 kg/hm2;而人工林则存在显著的差异,以 20~40 a 林龄的林分最大,为（34.22±2.77） ×103 kg/hm2,其次为大于 40 a 林龄的林分,为（23.34±0.72×103kg/hm2。在 20~40 a 林龄的生态公益林中,人工林平均碳密度显著大于天然林,但在大于 40 a 林龄的林分中,则显著小于天然林。     

Agroforestry farming systems in the homesteads of Kerala,southern India

Kerala State on the southwestern coast of India in the tropical humid zone has a predominantly agricultural economy, a very high density of population and therefore high pressure on cultivable land. The farmers there undertake cultivation of an array of crops — tree crops, plantation crops, seasonals and biennials — all in intimate mixtures on the same piece of land around the homesteads. Farm animals and poultry and sometimes fisheries also are essential components of the system. The close association of agricultural crops, tree crops and animals in the homesteads represents an excellent example of sustainable and productive agroforestry homegardens. Optimum utilization of available resources of land, solar energy and technological inputs and an efficient recycling of farm wastes are important characteristics of the systems. This paper attempts to describe and evaluate the systems' stability, productivity and sustainability, and identify its merits and constraints as well as research needs.     

The impact of the introduction of sustainable forest management objectives on the optimisation of PC-based forest-level harvest schedules

Previous to the introduction of sustainable forest management principles, PC-based modelling techniques had been developed for the financial optimisation of forest-level harvest scheduling under Irish conditions. These financial models were further developed to produce a Mixed Integer Programming-Sustainable Forest Management (MIP-SFM) model, in which principles of sustainable forest management were incorporated into the harvest scheduling process. The effectiveness and practicality of the harvest schedules produced by the financial model and the MIP-SFM model were compared to the harvest schedules produced by the process currently employed by Coillte (The Irish Forestry Board). Evaluation of the models was carried out in Clonbrock forest (294.8 ha), a typical Irish plantation forest, owned and managed by Coillte. The MIP-SFM model produced effective and practical harvest schedules that enhanced the sustainability of Clonbrock forest by incorporating environmental, ecological and social management parameters. The application of the developed MIP-SFM model resulted in an increase in NPV of 5.7% compared to the NPV produced by the scheduling process currently employed by Coillte. The application of the financial model had resulted in a comparable increase in NPV of 14.2%. The smaller increase in NPV produced by the MIP-SFM model provided an indication of the cost associated with the introduction of environmental, ecological and social SFM principles in the management of Clonbrock forest.     

Enhancing the value of multiple use plantations: a case study from southeast Queensland, Australia

In the 1990s, an expansion of small-scale (farm) forestry in medium to low rainfall areas was considered to be an important part of increasing the national forest estate but it remains a very minor source of timber, largely confined to the higher rainfall areas. In most areas, returns from timber are much less than for alternative land uses, even with low discount rates. If however, there are additional returns from plantation grazing and carbon sequestration and there are other potential management gains, multiple use plantations may be more attractive. The goal of this study is to estimate the net present values of multiple use spotted gum plantations in a medium rainfall area of southeast Queensland. For the case study, production, carbon sequestration and emissions data were supplemented by formal and informal interviews with landholders, sawmill staff and government extension personnel. Forest inventory, biomass and soil sampling, and stakeholder interviews were used as sources of primary data. The costs and benefits data were converted into monetary terms and discounted to produce net present values. Evaluations in this study identify the optimal rotation age of plantations to be 33–34?years. This is the case if including carbon and stock values, and using either farm- or factory-gate timber prices. The net present value increases significantly however if farmers harvest the trees themselves. In addition, at harvesting age, it was found that carbon and stock had the potential to account for 19.2 and 11.4?% respectively of the total returns from spotted gum plantations. Policy initiatives to support the farm forestry sub-sector should include pricing greenhouse gas emissions and developing and strengthening farmers co-operatives and marketing institutions to enhance farmers’ bargaining power.     

Exploring the Socio-Economic Situation of Plantation Villagers: A Case Study in Myanmar Bago Yoma

Since the early 1980s, Myanmar Forest Department has been recruiting shifting cultivators, establishing plantation villages and applying the taungya method in establishing teak plantations. From the beginning, there has been an argument about whether the program is creating ‘forest protective groups’ or ‘forest destructive groups’. A key determinant to that question from the research viewpoint is the socio-economic situation; knowing the present situation of the plantation villagers can help to understand their forest management practices. Interview surveys were carried out in three villages in Bago Yoma, the main region of the special teak plantation program, to examine the current economic benefits to plantation villagers. Questions were designed mainly to explore the incentives for people participation and the socio-economic situations of the plantation villagers. Principal component analysis was used to group landholder types. It was found that local people are willing to participate in the initial establishment of plantations. However, all the incentives relating to plantation projects are temporary, with no long-term consideration for taungya farmers, which jeopardizes the plan to create forest protective groups. It is concluded that the time has come for the Myanmar Forest Department to change its main aim of earning foreign exchange from establishment of teak plantations through the taungya method to redressing deforestation through people participation based on rural socio-economic development.

基于有限元热分析的长白落叶松人工林采伐迹地地表温度的研究

长白落叶松人工林采伐迹地具有与其他林地不同的独特性质,因此其地表温度变化也呈现特定的规律。本文应用有限元热分析的方法,利用线性单元建立热传导分析模型,对长白落叶松人工林采伐迹地地表的温度场进行分析。将分析结果与实测结果进行比较,验证了分析模型的可行性。表明基于有限元热分析的人工落叶松林采伐迹地地表温度模拟具有一定的实际意义,可以为长白落叶松人工林采伐迹地的更新改造、林木管理以及森林防火提供一定的理论依据。     

基于ArcGIS Engine帽儿山森林多资源管理系统的研建与实现

以C#语言为开发平台,以ArcGIS Engine为开发组件,以帽儿山实验林场的森林资源调查数据和地理信息数据为基础,进行森林多资源管理系统的设计与实现。该系统实现帽儿山实验林场地区森林多种资源信息的查询、分析与决策,其中包括GIS基本功能、专题图的生成、森林灾害管理和伐区采伐管理等功能,最终完成帽儿山实验林场的一个较为完善、专题性强和可扩充的森林多资源管理系统。该系统的研究与实现对帽儿山林场的经营管理及外业调查工作都有一定的实际意义。