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1.
Analysis of the changes in forest ecosystem functions,structure and composition in the Black Sea region of Turkey 总被引：1，自引：0，他引：1
We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability: economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types, tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas (especially in settlement and agricultural areas), forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches. 相似文献
2.
Community forest management helps in mitigating deforestation and forest degradation by addressing the negative aspects of rural livelihoods such as poverty and social exclusion. It is important in regulating global climate by encouraging sequestration of carbon in shoots, roots and soils. We studied the status of community forest management, forest resource harvest and carbon stocks in two community forests of the mid hill region of central and western Nepal. The study was based on primary and secondary data collected through carbon stock measurement from field visits and allometric equations, household surveys, focus group discussions, key informant interviews, and review of past studies. Socioeconomic variables such as gender, age group, livestock and landholding status were related to resource utilization, conservation, and management of community forest. Forest resources such as timber, firewood, fodder and leaf litter were harvested in sustainable ways. People were involved in forest thinning, co-management meetings, guarding and planting trees for forest conservation and management. Density and carbon stock of trees increased gradually in comparison to a previous study. We recommend further research on other community forests for more accurate and better results. 相似文献
3.
Anu Korosuo Per Sandström Karin Öhman Ljusk Ola Eriksson 《Scandinavian Journal of Forest Research》2014,29(7):234-251
In northern Sweden, the forests are used simultaneously for both timber production and reindeer husbandry. During the winter months, lichen is the most important fodder for reindeer. Forest management operations are generally considered having a negative impact on reindeer husbandry as harvesting and dense stands remove or obscure the ground lichen cover. In this study, we simulate three different scenarios for forest management, differing in the intensity and types of harvest operations. The resulting 100-year scenarios are analyzed with respect to their estimated suitability for providing reindeer pasture areas. Suitability is determined by vegetation type, stand density and stand height. The results indicate that the current trend of a decrease in lichen area will continue if existing forestry practice prevails. Implementing continuous cover forestry as a management alternative and carrying out precommercial thinning could halt the decrease in reindeer pasture area and even lead to a future increase in pasture area, with losses of approximately 5% in the net present value of forestry. 相似文献
4.
Coert J. Geldenhuys 《Journal of Forest Research》2010,15(1):3-13
How can we accommodate the diversity in tree species and sizes in mixed-species/size/age stands in the sustainable management of natural forests and woodlands in Africa for diverse timber and non-timber forest products and services, and during rehabilitation of degraded forests? The evergreen moist tropical to warm-temperate forests, from the equator to 34°S, generally function through relative shade tolerance. The tropical, strongly seasonal, drier deciduous woodlands generally function through adaptation to fire and/or grazing/browsing. Silvicultural systems, when implemented, are often not aligned with the ecological characteristics of the particular forest systems or the specific targeted species. This paper presents the concept of using the basic disturbance–recovery processes, with recovery development via stand development stages, as the basis for the development of silvicultural systems suitable for maintenance of forest complexity. Grain analysis and stem diameter distributions, analysed from resource inventories, are used to determine the specific shade- or fire-tolerance characteristics of key economical and ecological tree species. The gained knowledge of the ecosystem and species characteristics (including modes of regeneration, i.e. from seed or vegetative regrowth) and processes is used to simulate the ecological disturbance–recovery processes through the development of mixed silvicultural systems, such as a single-tree selection system, a group felling system and a coppice management system in the same forest. Very similar concepts are used to develop rehabilitation strategies to recover the processes towards regrowth stands of diverse species and structure: through stands of introduced plantations and invader tree species; and through early regrowth stages in deciduous woodlands and evergreen forests, after fire, slash-and-burn traditional agriculture, charcoal production or open-cast mining. 相似文献
5.
The Government of Indonesia (GoI) and the European Union (EU) have signed a Voluntary Partnership Agreement on Forest Law Enforcement Governance and Trade (FLEGT-VPA), which aims to prevent illegal timber products from entering the EU. This agreement recognizes a certification for timber products exported from Indonesia based on FLEGT-VPA standards and implemented through the timber legality verification system, Sistem Verifikasi Legalitas Kayu (SVLK). While the implementation of SVLK complies with the FLEGT-VPA, it has not dissolved pre-existing national systems for forest management and timber trade. Implementing SVLK standards amid multiple forest regimes causes redundancy of administrative procedures in forest management and timber trade in Indonesia. This redundancy, in turn, leads to decrease in cost efficiency, weak legitimation, and low effectiveness of the system, especially in community forests. 相似文献
6.
Harri Kilpeläinen Olli Salminen Kari Härkönen Jari Miina 《Scandinavian Journal of Forest Research》2018,33(4):378-386
In many areas, picking wild berries constitutes an important forest commodity offering food, recreational services, and revenues. Intensified forest management has negatively affected bilberry yields. In this study, regional-level scenario analyses were conducted to investigate the effects of four approaches to the inclusion of bilberry yields on the economics, management, and resulting forest structures in North Karelia. The current approach ignoring bilberries resulted in decreasing bilberry yields and increasing younger forests. When bilberries were valued at market price (1.72?€?kg?1), bilberry yields still decreased despite the fact that forest management were slightly modified to favour bilberry. Adding non-declining sustainability constraints to bilberry yields resulted in a slightly lower total net present value of timber and bilberry since forest management favoured longer rotation lengths, which increased bilberry yields. Similar effects occurred when the bilberry price was tripled to include the implicit ecosystem benefits of bilberries. When forests were managed only for bilberries (timber zero-priced), bilberry yields started to increase immediately resulting in 1.5-fold difference in 50 years as compared to timber only scenario. In conclusion, managing forests for both timber and bilberry production has rather minor effects on economics, but it can have clear positive effect on bilberry yields. 相似文献
7.
Timo Pukkala 《林业研究》2018,29(2):261-272
Forest management in several boreal countries is strongly focused on conifers because they are more productive,the technical quality of their stems is better,and their wood fibers are longer as compared to broadleaves.Favoring conifers in forest management leads to simple forest structures with low resilience and diversity.Such forests are risky in the face of climate change and fluctuating timber prices.Climate change increases the vitality of many forest pests and pathogens such as Heterobasidion spp.and Ips typographus L.which attack mainly spruce.Wind damages are also increasing because of a shorter period of frozen soil to provide a firm anchorage against storms.Wind-thrown trees serve as starting points for bark beetle outbreaks.Increasing the proportion of broadleaved species might alleviate some of these problems.This study predicts the long-term(150 years) consequences of current conifer-oriented forest management in two forest areas,and compared this management with silvicultural strategies that promote mixed forests and broadleaved species.The results show that,in the absence of damages,conifer-oriented forestry would lead to 5–10% higher timber yields and carbon sequestration.The somewhat lower carbon sequestration of broadleaved forests was counteracted by their higher albedo(reflectance).Mixed and broadleafforests were better providers of recreational amenities.Species diversity was much higher in mixed stand and broadleaf-oriented silviculture at stand and forest levels.The analysis indicates that conifer-oriented forest management produces rather small and uncertain economic benefits at a high cost in resilience and diversity. 相似文献
8.
Community forestry is an approach for mitigating deforestation and forest degradation by managing the forest resources for benefitting neighboring communities. Monetary benefits and costs are associated in a community forest during conservation and management of a forest. For sustainable forest management, the benefit should be more than cost which is a contesting issue of research. So, this study was conducted in a community forest of the central part of Nepal with the help of 80 household surveys and a focus group discussion. The firsthand information collected at the site is complimented by forest product harvest and cost-related secondary information. It was observed that the total annual harvest of timber was 60 cubic feet, pole was 8 cubic feet, firewood was 1,110 Bhari,1 fodder was 4,388 Bhari, and leaf litter was 590 Bhari. To manage a forest, people were involved in fencing, thinning, and meetings. Management cost was six times higher than administration cost. The benefit from firewood and fodder was more due to the dependency of people in a forest for enhancing their livelihood. The higher value of benefit cost ratio indicates that the Community Forest User Group benefited from community forest management. 相似文献
9.
Pine honeydew honey is an economically important non-wood forest product from eastern Mediterranean Pinus brutia forests, which are also important for timber production. Pine honey is produced by bees that feed on the honeydew secretions of Marchalina hellenica, a scale insect that infests pine stands and feeds on pine sap. The aim of this study was to optimize the joint production of pine honeydew honey and timber by maximizing the soil expectation value of pine stands. The simulation of P. brutia stand dynamics and timber production in healthy and infested stands is based on individual-tree growth and yield models that account for the effect of M. hellenica on tree- and stand-level growth and mortality. The optimization procedure uses a direct search method based on nonlinear programming. The results suggest that pine stands growing on good sites should be managed using rather short rotations and mainly aiming at timber production. In contrast, forest management in medium- and poor-quality sites should aim at longer rotations by taking advantage of the joint production of pine honey and timber assortments. Honey-oriented forest management can be much more profitable than timber production in stands growing on medium and poor sites. Pine honey represents an opportunity to increase the value and economic profitability of P. brutia forests. 相似文献
10.
Integrated forest management–pursuing multiple management objectives on the same area–is one important approach to reconciling conflicting demands towards forests. While a few studies have examined its implementation at a local level, the literature is thus far lacking detailed analyses of how forestry professionals perceive and implement the integration of multiple demands towards public forests, as well as what factors are influencing local level decision-making. This study attempts to fill this gap. Focusing on nature conservation aspects and their integration into public forest management, where a primary objective is timber production, we examine the implementation of integrated forest management in five German Länder (German federal states) as perceived by state forest enterprise rangers (Revierleiter). Our findings indicate a great willingness and commitment among forest rangers to implement integrative nature conservation approaches through integrated forest management. However, there are also a number of factors that hinder their implementation. In particular there is a mismatch between the demands placed on rangers and the support provided to them regarding time, more flexible timber targets, and financial as well as personnel resources. We argue that the practical implementation of integrative nature conservation requires more favorable conditions which can actually facilitate the balancing of multiple demands through integrated forest management. 相似文献
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12.
We classified forest resources into four modes: high timber output and high ecological reserve (Mode T-E); high timber output and low ecological reserve (Mode T-e); low timber output and low ecological reserve (Mode t-e); and low timber output and high ecological reserve (Mode t-E). Ecological reserve is stand volume per unit area of natural forests and total area of natural forests; timber output is defined as total area of timber forests and unit area of timber production. We used this classification system to examine forest development in China between 1950 and 2013. Data were acquired mainly from forest inventory statistics published by China’s Forestry Administration between the 1970s and 2013. I Information from the 1950s was acquired from relevant literature. Our analysis suggests that China’s forest resources transitioned from Mode t-E to Mode T-e during the period between the early 1950s and late 1970s, resulting in the destruction of both ecological vigor and timber resources. During the following 20 years, strategies were implemented to improve the ecological reserve and increase timber supply, resulting in a decline in the rate of forest degradation. Over the past decade, China’s forest resources have reached Mode T-E as a result of improvements in both the ecological reserve and the timber supply. Currently, the total area of timber forests is relatively low, representing the limiting factor for improvement in overall forest functionality. Nevertheless, along with increased efforts to protect natural forests and develop fast-growing forest plantations, it is hopeful that China’s forest resources will achieve a sustainable state. The four-mode TOER (timber output, ecological reserve) method introduced in this paper is a simple but an effective approach for characterizing the overall quality and quantity of forest resources. The data used for this type of evaluation are typically easy to obtain and reliable. This methodology has potential to be applied to forests in various regions and countries. 相似文献
13.
Viktor J. Bruckman Shuai Yan Eduard HochbichlerGerhard Glatzel 《Forest Ecology and Management》2011,262(9):1853-1862
Carbon pools in two Quercus petraea (sessile oak) dominated chronosequences under different forest management (high forest and coppice with standards) were investigated. The objective was to study temporal carbon dynamics, in particular carbon sequestration in the soil and woody biomass production, in common forest management systems in eastern Austria along with stand development. The chronosequence approach was used to substitute time-for-space to enable coverage of a full rotation period in each system. Carbon content was determined in the following compartments: aboveground biomass, litter, soil to a depth of 50 cm, living root biomass and decomposing residues in the mineral soil horizons. Biomass carbon pools, except fine roots and residues, were estimated using species-specific allometric functions. Total carbon pools were on average 143 Mg ha−1 in the high forest stand (HF) and 213 Mg ha−1 in the coppice with standards stand (CS). The mean share of the total organic carbon pool (TOC) which is soil organic carbon (SOC) differs only marginally between HF (43.4%) and CS (42.1%), indicating the dominance of site factors, particularly climate, in controlling this ratio. While there was no significant change in O-layer and SOC stores over stand development, we found clear relationships between living biomass (aboveground and belowground) pools and C:N ratio in topsoil horizons with stand age. SOC pools seem to be very stable and an impact of silvicultural interventions was not detected with the applied method. Rapid decomposition and mineralization of litter, indicated by low O-horizon pools with wide C:N ratios of residual woody debris at the end of the vegetation period, suggests high rates of turnover in this fraction. CS, in contrast to HF benefits from rapid resprouting after coppicing and hence seems less vulnerable to conditions of low rainfall and drying topsoil. 相似文献
14.
Adje Olivier Ahimin Steven Johnson François N’Guessan Kouamé Kagoyire Kamanzi 《Journal of Sustainable Forestry》2019,38(1):46-53
Sustainable forest management is the process of managing forest to achieve one or more clearly specified objectives without diminishing the forest’s ability to continue providing goods and services in perpetuity. In this paper, we show how the African Timber Organization/International Tropical Timber Organization principles, criteria and indicators for the sustainable management of African forests can help timber companies assess their progress towards this goal in Gabon. Through a partnership between International Tropical Timber Organization project PD 124/01 Rev. 2(M), the World Wildlife Fund, and the ministry responsible for forests in Gabon, audits were conducted between 2012 and 2014 to evaluate the implementation of sustainable forest management in 14 forest concessions in Gabon. In general, results show that Principle 4, linked to the well-being of workers and local populations, proved the most difficult principle to implement, while Principle 3, dealing with maintaining ecological functions, was the least problematic. A number of companies were found to be experiencing significant difficulties in implementing management plans. It is also clear that independent forest certification has become a key element for ensuring the successful implementation of sustainable forest management. 相似文献
15.
《Journal of Sustainable Forestry》2013,32(4):95-114
Ever-wet forests of SW Sri Lanka are biodiversity hot spots with a wealth of potentially useful and currently used species. Traditional peoples surrounding these forests depend on them for a variety of focds, medicinals and the like as well as for timber. Some of these forests are being preserved as storehouses of diversity that include rare endemics and wild relatives of useful plants. Other natural forests and plantations must be managed for multiple uses including timber and non-timber products used by the forest dependent villagers. Understanding the ecological, social and economic interdependence of forests and rural communities is vital for the future forestry sector development in Sri Lanka. As many of the plants used locally are characteristic of early stages of gap regeneration, timber and non-timber products are compatible uses, given sufficiently judicious management. Anthropological and biological research is now in progress to plan for multiple use management of Sri Lankan ever-wet forests. 相似文献
16.
Ajit Menon Christelle Hinnewinkel Claude Garcia Sylvie Guillerme Nitin Rai Siddhartha Krishnan 《Small-Scale Forestry》2009,8(4):515-527
Rural people in developing countries including India continue to access a number of types of ‘forests’ to meet specific needs
such as fuelwood, fodder, food, non-timber forest produce and timber for both subsistence and income generation. While a plethora
of terms exist to describe the types of forests that rural people use—such as farm forests, social forests, community forests
and small-scale forests—the expression domestic forest has recently been proposed. Domestic forest is a term aimed at capturing the diversity of forests transformed and managed
by rural communities and a way to introduce a new scientific domain that recognises that production and conservation can be
reconciled and that local communities can be effective managers. This paper argues in the context of the central Western Ghats
of south India that while the domestic forest concept is a useful umbrella term to capture the diversity of forests used by
rural people, these domestic forests are often not autonomous local forests but sites of contestation between local actors
and the state forest bureaucracy. Hence, a paradigm shift within the forest bureaucracy will only occur if the scientific
forestry community questions its own normative views on forest management and sees forest policy as a means to recognise local
claims and support existing practices of forest dependent communities. 相似文献
17.
18.
苍梧县低效防护林综合改造技术研究 总被引：1，自引：0，他引：1
苍梧县是珠江防护林体系建设的重点县。由于人为干扰、树种选择不当、经营措施不合理等原因,林分退化严重,生态环境遭到破坏,形成较大面积的低效马尾松纯林、湿地松纯林和低效次生阔叶林。本研究通过对低效林分的土壤理化性质、凋落物、植物多样性、生物量等的调查,提出了对苍梧县低效林采取异龄混交、调整群落结构、调控林分密度、抚阔补珍、抚针植阔和封育补植等一系列综合改造技术,并对几种低效林分改造后形成的不同林分结构的土壤物理、化学性质及持续特性等效果进行了初步评价。 相似文献
19.
上杭县林业发展潜力和可持续经营分析 总被引：1，自引：0，他引：1
根据森林和林业资源消长的客观规律,遵循“法正林”概念和经营模式,运用林木生长和收获模型研究结果,采用动态比较的方法,分析上杭县的林业资源结构及其缺陷,研究并提出了分类指导的经营策略。分析表明,通过科学规划和经营,县域用材林林分在实施分类经营的前提下,可以适度缩减面积,保留生长(立地)类型良好的林分实施集约化经营,在10 a经营期内,可以增加2倍的采伐量,林木蓄积增长73%。同时可以促进竹林、经济林、薪材林等资源的增长,促进林区生产的多样化,实现林业生产、林区经济的协调、可持续发展。 相似文献
20.
Understanding how soil fertility changes due to environmental conditions and stand-age-dependent for-est attributes is important for local-scale forest restoration.We evaluated the effects of stand-age-dependent forest attributes (plant community composition and litter stock)on soil and technosol fertility across two second-growth Atlantic forests (SGF) after the deposition of mining tail-ings in Mariana,southeastern Brazil.We hypothesized that technosol fertility in the SGF tailings is positively affected by plant community composition variability,stand age,and litter stock.We used total exchangeable bases and organic matter as fertility indicators for technosol and soil,and spe-cies composition and litter stock as stand-age-dependent forest attributes.Our results showed significant differences in the stand-age-dependent forest attributes and soil chemi-cal properties between the two forest patches (SGF tailing and SGF non-tailing) evaluated.Thus,there was a marked gradient of litter storage and fertility between soil and tech-nosol that can be important forest recovery indicators for the affected plant communities.Furthermore,according to the tested models,we corroborated the hypothesis that techno-sol fertility is positively affected by stand age,plant com-munity composition variability,and litter stock,which may contribute considerably to forest recovery on tailings.Our results demonstrate that the fertility predictors analyzed to explain the forest recovery on tailings can also be considered as ecological indicators for assessing forest restoration in areas impacted by mining tailings in Mariana. 相似文献