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1.
本论述了天然林资源保护与木材生产的关系,实施天然林资源保护后木材生产的发展方向,木材生产要服从和服务于天然林资源保护及预防实施天然林资源保护工程所带来的负效应。  相似文献   

2.
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.  相似文献   

3.
We compared the dead wood (DW) conditions of Cheshmeh-sar forest and Sardab forest with different management history,including reserve forest and harvested forest. The First forest took 100% inventory from all the available DW. Also dead trees were compared interms of species, shape, location and quality of fracture in both forests.Volumes of dead wood in Cheshmeh-sar and Sardab forests were 207.47and 142.74 m3, respectively. Due to this significant difference, impact onthe management level was determined. In Cheshmeh-sar forest, 42% ofdead trees were standing and 58% were fallen type while in Sardab forest 38.6% were standing and 61.4% fallen. But the difference was not statistically significant between them (p = 0.0587). In terms of quality, dead trees of hard, soft and hollow had the highest frequency, respectively.However, 71.5% of DW was seen as hard dead in Cheshmeh-sar forestwhile hard dead trees in Sardab forests were 54.2%. Soft quality degree ofdead trees which formed in Cheshmeh-sar and Sardab forest were calculated as 26.6% and 43.4% respectively. Also 30% of the dead trees of Sardab forest were eradicated while in Cheshmeh-sar this amount was reduced to 12%. Due to this significant difference ((Р=0/018), it is concluded that the type of management and human interference are affecting the quality of dead trees and makes us to think the human interferences could effect on the ecosystem of touched forests.  相似文献   

4.
Second-generation biofuels are often seen as essential element in the future bioeconomy strategy. Countries with extensive forest resources such as Norway often view wood as preferred bio-feedstock, yet the effects of wood demand on assortments of harvested wood and other wood-based industries are unclear. Focusing on the importance of feedstock choice, we analyse the impacts of establishing a second-generation medium-scale biofuel plant in Norway. For the analysis, a dynamic forest sector model where the choice of tree species, wood assortments, production of bioenergy, and forest industry products are explicitly included, was applied. We find the optimal biofuel feedstock mix to be dominated by softwood chips from pulpwood comprising 48% of total biomass inputs in 2030 and increasing to 67% by 2055, followed by hardwood chips from birch, comprising initially 34% of total biomass inputs and 16% by 2055. The proportion of harvest residues remained constant at about 18% over time and roundwood was not used at all for biofuel production. Despite the additional demand for chips, the single medium-scale biofuel plant will have only minor effects on existing forest industries and harvests in Norway, as the domestic impact is dampened by changes in foreign trade flows, especially of chips.  相似文献   

5.
Abstract

Red wood ants of the Formica rufa group, as well as their nests, form a vital part of the ecosystems of both European and Siberian boreal and temperate forests. It has been well documented that the nests of red wood ants in clear-cuts do not perform as well as those deeper in the forest. However, clear-cuts may not be a homogeneously poor habitat for such forest-dwelling ants because the distance of the nest site to the edge of the remaining forest may be a significant factor affecting the nest performance. In this study, I compared the probability of nest survival and sexual offspring production between the nests of Formica aquilonia (Yarrow, 1955) in a forest edge zone (distance to the forest edge <9.2 m) and a clear-cut centre zone in 18 different clear-cut areas. Although the nests were generally smaller, the probability of sexual offspring production and nest survival was higher among those nests in the edge compared to the centre zone. Since the proximity to the forest edge increased the performance of a nest, selective logging and smaller scale clear-cuts may not be as harmful to red wood ants as clear-cutting over a large area.  相似文献   

6.
赵敏  周广胜 《林业研究》2004,15(2):93-100,i001
准确地评估森林净第一性生产力(NPP)对于评估全球收支有着十分重要的作用。本文充分利用森林资源清样调查资料,并动态地评估森林生产力,以油松林为例建立了反映生物因素(蓄积量V和林龄A)和气候因素(年实际蒸散E)综合影响的中国油松林生物气候生产力(NPPa)模型。基于所建模型和第四次我国油松林资源的清样调查资料(1989-1993年),估算了中国油松林的净第一性生产力,并借助于地理信息系统软件给出了中国油松林的分布格局。结果表明:我国油松林的平均净第一性生产力为7.82thm-2a-1,其变化幅度为3.32~11.87thm-2a-1。中国油松林净第一性生产力有明显的区域差异,表现为南高北低的分布趋势。山西和陕西为中国油松林的集中分布区,生产力水平处于中等,约为7.4thm-2a-1;油松林集中分布区的南部(四川、湖北、河南等省),生产力水平较高,均大于7.7thm-2a-1;而在油松林集中分布区的北部和西部(内蒙古、宁夏等省),生产力水平较低,NPP均低于5thm-2a-1。该研究为利用森林资源清样调查资料评估森林NPP的动态及研究其对气候变化的响应提供一个有效思路。图3表2参46。  相似文献   

7.
The global to local-level importance of Indonesian forests for the environment and development is now very well documented. However, how to govern these forests to achieve the diverse and, at times, conflicting interests is still an open question. Hutan Kemasyarakatan (HKm) is a community forest (CF) that is being implemented to contribute to local development while creating sufficient incentives for conserving the forest. Previous studies have demonstrated the potential of HKm to conserve forests. This study analyzed the changes in the five major types of capital for HKm farmers. The results indicated HKm to have contributed positively to the improvement of natural, physical, and human capital. In addition to its direct impact, HKm was also found to improve the financial capital of the farmers by avoiding patron–client relationships and side payments between the pre-HKm illegal encroacher farmers (now legal land cultivators) and government officers. Although the results support the possibility of HKm producing a win-win situation between forest conservation and rural development, its future applicability, especially with consideration of population growth and associated increase in demand for cultivation land, needs to be given due emphasis.  相似文献   

8.
During the first half of the 20th century the Baltic States were independent democratic nations where private forest ownership was practiced. After annexation to the Soviet Union, individuals in the Baltic States lost their ownership rights and collective ownership was introduced. Currently, after the break-up of the Soviet Union, the land restitution process in the forest sector is coming to an end and the ownership pattern as well as tenure rights are settled. A survey was undertaken to investigate the current state of the private forest sector in general, and the needs and expectations of private forest owners (PFO). Results of the study indicated that for private forest owners their forests first of all provide aesthetic and environmental protection values. Lithuanian PFOs lack information of forests and forest management, face extensive bureaucracy and need help in protecting their forests from fires, diseases and timber thieves.  相似文献   

9.
Forest sector models are widely used for policy and economic analyses. Basic assumptions vary considerably between models, but little attention has been paid to the impacts these differences may have on model results. Norway provides a great opportunity to fill this void as it has two forest sector models currently in use based on different modeling assumptions, but sharing the same data source. In one model, agents are assumed to be myopic in the meaning that they rely only on the current market conditions. Harvest behavior is in this model based on econometric relations and exogenous forest growth rates. The second model approach employs extensive forest data and assumes that agents have perfect information over the model time horizon. We discuss the differences between the two modeling approaches and compare quantitatively the model results of two case studies. However, both types of models are rather sensitive to changes in assumptions and data. The strengths and weaknesses of the two model approaches and their appropriateness for responding to the study questions should be considered when choosing modeling methodology. Using both models in parallel removes the uncertainty caused by the foresight assumption/optimization routine and thus provides in total more information.  相似文献   

10.
Three process-based approaches to agroforestry modelling are described. These are (a) coupling a continuous-canopy forest model (Hybrid) and tropical crop model (PARCH); (b) coupling an individual-tree model (MAESTRO) with a crop model (PARCH); and (c) incorporating a combined model of evaporation and radiation interception by neighbouring species (ERIN).The coupled Hybrid/PARCH was parameterised for maize and eucalyptus, and run in five contrasting weather-types. As expected, shade is the most important factor limiting yield in wet sites; water in dry sites. Year-to-year variability in crop yield is increased by light and water competition. MAESTRO/PARCH was run with similar assumptions, and gave comparable yield predictions, except at the driest site where it allows small areas distant from the tree sufficient water to produce a modest yield. Hybrid/PARCH predicted total crop failure in the same climate. Yields on drier sites were higher in the shade, but water competition was severe close to the tree.ERIN is simpler than the above models, but is unique in including the transfer of heat and water vapour between the two canopies. Transpiration from a moist understorey can humidify air in the overstorey, and reduce its transpiration; whilst a dry understorey will give off sensible heat, which increases the vapour pressure deficit in the overstorey and causes its transpiration to increase. Changes in overstorey transpiration due to fluxes from the understorey may approach 15–20%.  相似文献   

11.
This paper examines interactive change and adaptation of human and natural systems in two pioneer forest settlements in the Philippines. The forest ecosystem was converted by logging, further resource extraction by settlers, and cultivation — factors usually associated with systems degradation. Natural succession, however, was rapid because of high rainfall and abundant forest seed stocks; and because of high rainfall, weeds, insect pests, and poor soil — annual cereal and cash cropping was not profitable or sustainable and farmers turned to root and mixed perennial cropping. This naturally developing, more sustainable agroforestry was initially financed by boom-and-bust incomes from small scale logging and charcoal making, and took place in spite of the settlers' formation of factions and an us before them attitude towards resource use.  相似文献   

12.
Forest inventories based on airborne laser scanning (ALS) have already become common practice in the Nordic countries. One possibility for improving their cost effectiveness is to use existing field data sets as training data. One alternative in Finland would be the use of National Forest Inventory (NFI) sample plots, which are truncated angle count (relascope) plots. This possibility is tested here by using a training data set based on measurements similar to the Finnish NFI. Tree species-specific stand attributes were predicted by the non-parametric k most similar neighbour (k-MSN) approach, utilising both ALS and aerial photograph data. The stand attributes considered were volume, basal area, stem number, mean age of the tree stock, diameter and height of the basal area median tree, determined separately for Scots pine, Norway spruce and deciduous trees. The results obtained were compared with those obtained when using training data based on observations from fixed area plots with the same centre point location as the NFI plots. The results indicated that the accuracy of the estimates of stand attributes derived by using NFI training data was close to that of the fixed area plot training data but that the NFI sampling scheme and the georeferencing of the plots can cause problems in practical applications.  相似文献   

13.
生态文明建设是中华民族永续发展的千年大计,要促进生态、文化和旅游的相互融合。森林旅游解说作为森林旅游过程中必不可少的传播手段,在我国生态文明建设中发挥着重要的作用。以往的文献中,多从游客角度来研究旅游解说规划,空间视角的相关文献甚少,且研究单一。旅游移动性作为旅游的本质属性,从空间视角认识旅游解说规划中的信息与媒体关系将有助于编制科学的旅游解说规划。以湖南天际岭国家森林公园为例,基于实地访谈法与内容分析法,通过对点-线-功能区-公园-区域等5个空间尺度下的80名游客解说需求与媒体偏好进行研究,构建了森林公园解说规划空间尺度、信息需求与媒体偏好概念模型,具有一定的创新性。研究发现,处于不同空间尺度下的游客对解说信息与媒体偏好存在较大的差异性,并指出游客解说信息需求呈现一定的尺度上升趋势,反之则表现不明显。  相似文献   

14.
In recent years, worldwide socioeconomic, ecological, and cultural changes have led to a paradigm shift in forestry and forest management. Some years ago, most forest enterprises exclusively focused on wood production, whereas today, forest management is expected to be multifunctional and economically as well as socially and ecologically sustainable [Harrison, S., Herbohn, J., Niskanen, A., 2002. Non-industrial, smallholder, small-scale and family forestry: what's in a name? Small-scale Forest Economics. Management and Policy 1 (1), 1–11; Schmithuesen, F., 2004. Forest policy developments in changing societies — political trends and challenges to research. Towards the sustainable use of Europe's forests: Forest ecosystems and landscape research: Joensuu: European Forest Institute, Proc., vol. 49, pp. 87–99]. In this context, non-timber forest products (NTFPs) such as forest honey, mushrooms, or berries could gain importance as an additional source of income for the forestry sector. To assess the market potential of NTFPs in Switzerland, two corresponding surveys were conducted. A consumer survey (N = 897) conducted in six cities in Switzerland investigated the purchase of Swiss NTFPs, consumer preferences, and demand potentials. An additional survey of sellers of NTFPs (N = 105) looked at these aspects from a complementary perspective. The results showed that there is a high esteem and considerable demand potential for such products among urban consumers. Food products were mentioned most frequently. Both consumers and sellers considered quality and environmental friendliness the most important attributes of NTFPs. Structural and organizational innovations and considerable marketing efforts and sales promotion would be required to expand the market for Swiss NTFP, however. Our results indicate that certification of the products' origin, environmental performance, and quality could support such efforts and that recreational and ecological forest services have a synergetic potential for the marketing of NTFPs.  相似文献   

15.
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.  相似文献   

16.
为满足新时期国家级公益林保护管理需要,根据国家新修订的国家公益林区划界定要求,本文结合当前森林资源档案现状,总结了国家级公益林区划界定方法及存在主要问题,为国家级公益林保护管理提出建议,为进一步完善国家级公益林管理提供参考。  相似文献   

17.
The Forest Department in the State of Uttar Pradesh, India developed Forest Management Information System (FMIS) for achieving organizational goals of improved financial and human resource management, improvement in the management of forests and wildlife, and for achieving responsive administration. This paper, based on field research, presents an assessment of the dynamics of FMIS in organizational context for a better understanding of such systems in forestry organizations. The paper also investigates the success of FMIS in assisting decision makers in achieving organizational goals. Based on the knowledge developed during the course of the study, key learning elements have been highlighted for the benefit of the stakeholders in information systems in forest sector.  相似文献   

18.
Our study focuses on the social performance of state-owned forest farms and proposes a framework for evaluating both resource-based and corporate-based approaches. We found that: (1) the overall average social performance score of the sample of state-owned farms (3504 farms) assessed using our framework was 41.56 (out of 100 points), indicating that the social performance of Chinese state-owned farms was relatively low. (2) More developed provinces scored higher than less-developed ones, revealing a regional difference in social performance with respect to sustainable forest management (SFM). The clear implication here is that state-owned forest farms in less-developed regions can improve their social performance by striving to improve forest and ecological culture development, science and education, employment, stakeholder participation, forest services, etc. (3) The state-owned forest farms have developed a more balanced use of forest resources. The results suggest that social performance requires greater attention from managers and decision-makers in the long-term, and they may wish to consider adopting it as a corporate management tool. In general, our study suggests a practical framework for integrating social performance into SFM decisions and policies.  相似文献   

19.
Environmental education (EE) is a vital dimension of modern day acumen that portends a great promise in solving the myriad environmental resource management challenges at global, regional and local levels. A study was carried out in 18 locations in the Nandi North, Nandi South and Nandi Hills districts of Kenya, which cover the Nandi Hills and Nandi Forests in Nandi County, major water catchments for Lake Victoria. A mixed methodological approach, incorporating both qualitative and quantitative data obtained from focus group discussions, key informant interviews, household survey and observations was embraced in data collection and analysis. The study reveals that there are several strategies that have been adopted by the local population and institutions involved in the management of the Nandi Hills Forests (NHFs) and that these strategies have contributed to an improvement in the perceptions of the local population in terms of the importance of environmental management of the forests. This paper highlights EE as a vehicle for ensuring a sustainable management of the Nandi Hills Forests. As such, it illuminates the great potential that lies in sustainably managing the NHFs by integrating formal and informal EE approaches. It further points out the functional gaps in the management of NHFs and proposes best-practices that could be adopted and/or domesticated in NHFs management regimes.  相似文献   

20.
本文针对国营林场产权制度存在的主要问题,借鉴国有林权制度改革的经验,提出国营林场产权制度改革的初步设想。  相似文献   

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