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1.
Forest management strategies, reflecting the cognition and the demands of the human population on forests, have significant effects on the forest structures and functions. Nowadays, numerous forest management strategies have been introduced and implemented worldwide for a long time. However, our knowledge about the impacts of alternative management strategies on forest multipurpose management practices is still insufficient. Therefore, the overall goal of this study quantitatively assessed the impacts of four alternative forest management strategies on forest timber and carbon values in a large forest area in northeast China, as an example. Four alternative forest management strategies: no intervention management (NIM), classical timber management (CTM), multi-purpose management (MPM), and spatial-constraints management (SCM), in conjunction with different management objectives and regulations, were quantitative assessed using optimization methods. The results of numerical analysis showed that implementing eco-friendly forest management strategies such as imposed in MPM and SCM strategies may be economic inefficiencies, mainly due to significant decreases of the joint benefits from forest timber and carbon values (approximately $18.75 and $22.36 million per year) have been observed under the current carbon trading market of China (namely $20 per ton of carbon) when the ecological- and spatial-oriented constraints were further integrated into the typical CTM strategy. However, both MPM and SCM strategies were quite meaningful for the restoration of forest resources in northeast China, in which an additional of 13.6 and 16.2 thousand tons of carbon were sequestrated during the 50 years simulated horizon. Therefore, forest decision makers should evaluate the potential effects carefully prior to altering their forest management strategy in practices. 相似文献
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We used a goal programming technique to determine the optimal harvest volume for the Iranian Caspian forest. We collected data including volume, growth, wood price at forest roadside, and variable harvesting costs. The allometric method was used to quantify seques- trated carbon. Regression analysis was used to derive growth models. Expected mean price was estimated using wood price and variable harvesting costs. Questionnaire was used to determine the constraints and the equation coefficients of the goal programming model. The optimal volume was determined using the goal programming method according to multipurpose forest management. LINGO software was used for analysis. Results indicated that the optimum volumes of species were 250.25 m3.ha-1 for beech, 59 m3.ha-1 for hornbeam, 73 m3.ha-1 for oak, 41 m3.ha-1 for alder, and 32 m3.ha-1 for other species. The total optimum volume is 455.25 m3.ha-1. 相似文献
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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
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《Southern Forests》2013,75(4):297-303
Temperate forests are globally important carbon stores that are, in the face of recent improvements in their conservation, likely to increase their storage capacity in the future. Despite this, these ecosystems are poorly understood, especially over longer time periods. To remedy this and to better understand these important ecosystems, we monitored marked stems >5 cm diameter at breast height (DBH) in a 0.52 ha forest plot on the Cape Peninsula over 26 years. Aboveground biomass (AGB), calculated from stem diameter, increased from 203 to 226 Mg ha?1 over this period. The AGB residence time was greater than a century. Stem mortality was relatively high (1.2% per annum [p.a.]) and exceeded recruitment (0.2% p.a.). The recruitment of a large number of smaller stems of species not presently represented in the forest canopy suggests that compositional changes will occur in the future. Overall, these results suggest that the forest is in a post-disturbance recovery phase, although favourable climatic conditions over the last three decades may also have had an influence on AGB accumulation. 相似文献
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A deterministic dynamic bio-economic model was used to analyse different management options for goats and charcoal production in a forest in Zagros, Iran. The study sought optimal management options from a local community point of view considering net present value (NPV) of income from sale of goats and charcoal under different restrictions on forest harvest imposed by the state. The model was run under six model scenarios: (1) business as usual (BAU), (2) no state intervention, (3) no forest harvesting, (4) strict quota, (5) medium quota and (6) loose quota on charcoal production. The scenarios' results were compared based on four numeric criteria (NPV of income from goats and charcoal, development of standing volume and tree size diversity in forest, interaction between goat population and oak forests) and one subjective criterion (state budget for managing forest). The results indicated that two main challenges exist in forest management in Zagros; (1) to determine the balance between local communities' welfare and biological stability of the forest and (2) to choose between a cheap management regime prohibiting wood harvest but implicitly accepting some illegal charcoal production and a more expensive, but legal, harvest regulation through charcoal production quota. We conclude that the BAU scenario, where forest harvesting was prohibited de jure, but some illegal charcoal production was still undertaken, was the only viable management, which also is practically acceptable by both state and local communities. 相似文献
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Determining the optimal rotation period was a crucial component of forest sustainable management strategies, especially under climate change. This paper had two objectives: (1) to determine the economic benefits and optimal rotation periods for timber production when coupled to carbon sequestration, as predicted by time series prediction models for Pinus tabulaeformis plantations in China; and (2) to evaluate how different carbon prices and interest rates affected optimal rotation periods using the forest land expectation value. The results suggested that time series prediction models were valuable for estimating timber volumes and carbon sequestrations based on surveys of different-aged stands. Importantly, since integrating carbon sequestrations into timber production benefits did not increase optimal rotation periods, this should promote P. tabulaeformis plantation management. In the sensitivity analysis, a higher carbon price increased the profitability of carbon sequestration and timber production, but not optimal rotation periods, though they were reduced under higher interest rates. In conclusion, incorporating both timber production and carbon sequestration benefits would sharply increase forest-based revenues, while realizing the carbon sequestration potential of P. tabulaeformis plantations. This approach was clearly useful to the development of reforestation/afforestation projects trying to mitigate climate change and also provided a theoretical basis for sustainable forest management. 相似文献
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Jalal Henareh Khalyani Manouchehr Namiranian S. M. Heshmatol Vaezin Jahangir Feghhi 《林业研究》2014,25(1):205-210
We examined the local community incentive programs to improve traditional forest management in three forested villages in Baneh city, Kurdistan province in the northern Zagros forests of western Iran. Zagros forests cover 6.07 million ha and support rich plant and animal diversity. Changes in local community social and economic sys-tems and the inefficiency of traditional forest management led to a criti-cal situation in the stability of forest regeneration in recent decades. Due to a shortage of productive and arable lands and resulting unemployment and poverty, people overexploited the Zagros forests. Outside interven-tion in traditional forest management creates conflicts between local peoples and forest management organizations. To achieve sustainable forest management, including forest resources conservation and im-provement of natural resource based livelihoods of communities, it is desirable to implement Forestry Incentive Programs (FIP) based on the important functions of forests. Detailed information on the so-cio-economics of communities, the effect of forests on local livelihoods, and lists of products extracted from the forest were obtained from a sur-vey of local communities though questionnaire, interview and observa-tion. We studied 276 households in three villages and completed 76 ques-tionnaires by householders in the quantitative analysis. Sampling was performed by simple random sampling (SRS). The needs of rural com-munities, such as livestock husbandry, mainly arise from the characteris-tics and environmental features of villages. We identified the driving forces, pressures, status, impacts and responses (DPSIR) to design incen-tive programs, by DPSIR analysis and interaction analysis. Evaluation of local community benefits from forests showed that in order to improve forest management, 319 dollars per year would be needed by each family as an incentive in 2010 to prevent lopping and firewood collecting, the main causes of forest degradation. 相似文献
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Emin Zeki Başkent Ali İhsan Kadıoğulları 《Scandinavian Journal of Forest Research》2014,29(7):121-131
Decision support systems (DSSs) are indispensable tools in preparing a forest management plan for a better combination of multiple forest values. This study attempted to develop and explain a stand-based forest management DSS (Ecosystem-based multiple-use forest planning [ETÇAP]) comprising a traditional simulation, linear programming (LP), metaheuristics and geographic information system. The model consists of five submodels; traditional management approach to handle inventory data, an empirical growth and yield model, a simulation to conceptualize management actions, a LP technique to optimize resource allocation and a simulated annealing approach to directly create a spatially feasible harvest schedule. The ETÇAP model has been implemented in a comparative two case study areas; Denizli–Honaz and Akseki–Ibrad?. Both simulation and optimization models outperformed to the traditional management plan. The periodical change of growing stock, allowable cuts, carbon sequestration and water production are used as performance indicators. The results showed that more amount of wood could be harvested over time compared to traditional level of harvesting. It could be concluded that various management strategies allowed managers to stimulate more decision options for better outputs through intertemporal trade-offs of management interventions as the model provided tools to quantify forest dynamics over time and space. Challenges exist to establish the functional relationships between forest structure and values for better quantification and integration into the management plans. 相似文献
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The subject of risk management is attracting more and more attention around the world. The risk of forest fire disasters should
be faced and dealt with for forest fires cannot be avoided. Treating forest fire disasters as a risk management issue promotes
important measures and methods for fire fighters to prevent, reduce and control the risks of forest fires. In this paper,
the risk concept and risk connotation as well as the management risks for forest fire suppression are discussed clearly. Issues
such as risk judgments, risk analysis, risk control and the assessment of risk, including their contents and corresponding
methods are clarified.
Translated from Forest Resources Management, 2006, 2: 24–27 [译自: 林业资源맜理] 相似文献
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《Southern Forests》2013,75(4):329-338
Supply chain management principles were analysed by investigating the effects of smaller-scale and incremental interventions in a forest-to-mill value chain on financial returns and forest resource use in an Eastern Cape case study area. Three previous studies provided input by determining fibre balances, a terrain factor, and primary and secondary transport travel speeds and efficiencies. Network analysis, combined with raster-based GIS, analysed different primary and secondary transport scenarios. The forest road network was repeatedly refined through theoretical removal of lower-class roads and subsequent upgrades of remaining roads, and the timber resource flowed over the remaining road network to the mill. Four road networks, including the existing and unrefined network, were studied. With sequentially improved secondary transport travel speeds, primary transport efficiency and fibre use, the net financial returns of the various scenarios were determined by applying discounted cash flow analysis (NPV). To address all possible combinations, 144 unique scenarios were created. The highest NPV achieved was R300.8 million associated with a highly upgraded road network and associated fast secondary transport speeds, cable skidder extraction, motor-manual felling and cross-cutting at the merchandising yard, all factors at optimal performance. The lowest NPV was R40.4 million associated with a simplified road network, low secondary transport speeds, cable skidder extraction, mechanised felling, and roadside merchandising and at status quo systems performance. Examination of individual factors found systems performance, secondary transport speeds and road network had the greatest influence, with systems performance and fibre losses providing the largest impact. Secondary transport speed followed as nine of the top 10 NPV scenarios were achieved with the highest possible road design speeds. Higher-class networks consistently outperformed the baseline and simplified scenarios. Harvesting system had limited effect. When operating at peak performance, using a merchandising yard becomes a better choice. There was no clear difference in terms of felling method or skidder type. It is clear that the optimised use of potentially the most productive machine, for example in one system, does not provide the best final results and that it is the basic harmonisation of all factors that must be taken into account. As in all three previous and related studies, the human element played a role. 相似文献
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Forest carbon storage in the northeastern United States: Net effects of harvesting frequency,post-harvest retention,and wood products 总被引:1,自引:0,他引:1
Temperate forests are an important carbon sink, yet there is debate regarding the net effect of forest management practices on carbon storage. Few studies have investigated the effects of different silvicultural systems on forest carbon stocks, and the relative strength of in situ forest carbon versus wood products pools remains in question. Our research describes (1) the impact of harvesting frequency and proportion of post-harvest structural retention on carbon storage in northern hardwood-conifer forests, and (2) tests the significance of including harvested wood products in carbon accounting at the stand scale. We stratified Forest Inventory and Analysis (FIA) plots to control for environmental, forest structural and compositional variables, resulting in 32 FIA plots distributed throughout the northeastern U.S. We used the USDA Forest Service's Forest Vegetation Simulator to project stand development over a 160 year period under nine different forest management scenarios. Simulated treatments represented a gradient of increasing structural retention and decreasing harvesting frequencies, including a “no harvest” scenario. The simulations incorporated carbon flux between aboveground forest biomass (dead and live pools) and harvested wood products. Mean carbon storage over the simulation period was calculated for each silvicultural scenario. We investigated tradeoffs among scenarios using a factorial treatment design and two-way ANOVA. Mean carbon sequestration was significantly (α = 0.05) greater for “no management” compared to any of the active management scenarios. Of the harvest treatments, those favoring high levels of structural retention and decreased harvesting frequency stored the greatest amounts of carbon. Classification and regression tree analysis showed that management scenario was the strongest predictor of total carbon storage, though site-specific variables were important secondary predictors. In order to isolate the effect of in situ forest carbon storage and harvested wood products, we did not include the emissions benefits associated with substituting wood fiber for other construction materials or energy sources. Modeling results from this study show that harvesting frequency and structural retention significantly affect mean carbon storage. Our results illustrate the importance of both post-harvest forest structure and harvesting frequency in carbon storage, and are valuable to land owners interested in managing forests for carbon sequestration. 相似文献
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ABSTRACTCarbon-based payments for ecosystem services solely consider afforestation and reforestation to assess sequestration. However, political ecology researchers demonstrate that tropical forests are complex socioecological systems where humans and institutions play an integral role in shaping landscapes. The current framing overlooks the net effect of traditional subsistence agriculturalists leaving behind low emission lifestyles, despite the likelihood of a significant increase in per capita emissions over time. In this case study, we use the history of forest use in the Pueblos Mancomunados—a commonwealth of indigenous communities in Oaxaca, Mexico—to explore sequestration through a socioecological systems lens. As negative emissions programs consider afforestation, we triangulated semistructured interviews, an unsupervised GIS classification of land cover, and a review of carbon dioxide emissions to consider out-migration, abandonment, and lifestyle change. We find that communities are struggling to maintain livelihoods as migration to urban centers and the United States continues. Meanwhile, spatial analysis revealed 800 ha of afforestation. Our analysis of out-migration scenarios and per capita emissions changes identified a tipping point in which no net-sequestration would occur from afforestation due to the changing lifestyles of the migrants and recommend improved local development to avoid this form of “leakage” when assessing global carbon stocks. 相似文献
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Relationship between vegetation carbon storage and urbanization: A case study of Xiamen, China 总被引:1,自引:0,他引:1
Yin RenXing Wei Xiaohua WeiJunzhong Pan Pingping XieXiaodong Song Dan PengJingzhu Zhao 《Forest Ecology and Management》2011,261(7):1214-1223
Rapid growth of the Chinese urban population and the expansion of urban areas have led to changes in urban forest structure and composition, and consequently changes in vegetation carbon storage. The purpose of this study is to quantify the effects of urbanization on vegetation carbon storage in Xiamen, a city located in southern China. Data used for this study were collected from 39,723 sample plots managed according to the forest management planning inventory program. Data from these plots were collected in 4 non-consecutive years: 1972, 1988, 1996 and 2006. The study area was divided into three zones, which were defined according to their level of urbanization: the urban core, the suburban zone, and the exurban zone. Total vegetation carbon storage and the vegetation carbon density for each study period were calculated for each zone. Our results show that urban vegetation carbon storage has increased by 865,589.71 t during the period from 1972 to 2006 (34 years) in Xiamen, with a rapid increase between 1972 and 1996, then relatively little change between 1996 and 2006. The increase in vegetation carbon storage is mainly due to the large percentages of the suburban and exurban areas which exist in Xiamen city, and the implementation of reforestation programs in these two zones. The percentage of total regional carbon storage in the city center (urban core), suburbs and exurbs was 5%, 23% and 72%, respectively. This demonstrates that the exurbs store the majority of vegetation carbon, and thus play a critical role in the vegetation carbon storage of the study area. The intensification of urbanization in the future will likely expand the urban core and reduce the area of the suburbs and exurbs, and thus potentially decrease total vegetation carbon storage. This article concludes with a discussion of the implications of these results for vegetation carbon management and urban landscape planning. 相似文献
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From a conceptual point of view, national forest management standards in Latin American countries have progressed significantly in recent years. Examples include the Costa Rican Standards and Procedures for Sustainable Forest Management and Certification, developed by the National Commission for Forest Certification and in Nicaragua, the National Institute of Forestry proposal of principles, criteria and indicators for sustainable forest management. In line with general approaches worldwide, these national standards primarily focus on the fulfillment of sound forest practice. There is comparatively little emphasis on the assessment of management outcomes or changes in key components of the eco- and social-systems that result from management impacts. Essentially, there is little emphasis on adaptive management, though arguments that management cannot be sustainable if it is not adaptive are persuasive. This study sought to contribute to the development of standards that include elements for adaptive management that define, communicate and evaluate sustainable forest management in Costa Rica and Nicaragua. Elements from the national standards and the CIFOR generic C&I template (predominantly focused on forest management outcomes) were used as a starting point. The basic research process consisted of three phases of evaluation (in-office, desk and field). The evaluations were carried out by multidisciplinary, international groups of experts in forest ecology, management and policy. This study demonstrated the value of forums and workshops that facilitate exchange between forest scientists and policymakers; the innovation and application of a practical, applicable and scientifically based methodology for developing national level C&I; and acceptance of this methodology by key players in the fields of forest management and policy. These experiences and the resulting proposals of C&I for the evaluation of ecologically sustainable forest management are expected to be used as points of reference for future development of forest policy in Costa Rica and Nicaragua, and to contribute to the overall understanding of C&I development processes in the region. 相似文献
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Forest cover and land use change directly impact biological diversity worldwide, contribute to climate change and affect the
ability of biological systems to support human needs by altering ecosystem services. Given the forest land use characteristics
and ecosystem types in Luang Namtha Province, Lao PDR, the forest cover and land cover category of Luang Namtha Province were
divided into six classes, i.e., current forest (CF), potential forest (PF), other wooded areas (OW), permanent agricultural
land (PA), other non-forest areas (NF) and water (W). In first instance, earlier geographic information data (GIS data) of
forest cover and land use during 1992 and 2002 was obtained from the Ministry of Agriculture and Forestry (MAF), Lao PDR.
Two steps of forest land use change assessment were conducted by the MAF, i.e., plot sampling on satellite image maps (SIMs)
to detect the changes of forest cover and land use during 1992 and 2002 for the entire Luang Namtha Province and field verification
in order to identify causes of the changes. Secondly, dynamic information of the forest land cover changes during this ten-year
period was calculated by means of map algebra in ArcGIS 9.2. Thirdly, based on the theory of ecosystem service functions and
the service function values of different global ecosystems, the value of the six forest cover and land use categories in the
province was obtained. Finally, ecological environmental effects, produced by the regional land cover changes over the study
period, were calculated. 相似文献
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Md. Motiur Rahman Yasushi Furukawa Isao Kawata Mohammed Mahabubur Rahman Mahbubul Alam 《Small-Scale Forestry》2005,4(3):359-376
This study examines the species composition, diversity and economic importance of homestead forests in the household economy
of central Bangladesh. The study documents 57 homestead forest species and their main usage in 90 households across three
villages of Gazipur Sadar Upazila. Homestead forests in Bangladesh comprise a mixture of fruit, timber and bamboo species.
While superficially homestead forestry appears unimportant in rural livelihoods, in reality the contribution is huge, both
as a source of food security and for other necessary household materials. A clear understanding of the physical characteristics
and economic role of homestead forests in rural livelihoods is vital for ensuring sustainable resource management. Income
and production of homestead forestry on a per hectare basis are found to vary widely between landholding size classes. Significant
relationships are identified between forest performance (production and income) and species richness and education level.
Homestead forestry appears to be a potential subsistence income generating land-use practice in the study area. The economic
scope of homestead forestry can be further enhanced provided the appropriate species composition of the forest is achieved
and the education of forest owners is ensured through targeted management and policy interventions. 相似文献
19.
Michael Khl Wolfgang Stümer Bernhard Kenter Thomas Riedel 《Forest Ecology and Management》2008,256(3):229-236
The IPCC-GPG on Greenhouse Gas Monitoring offers countries several options for reporting. The current study selected management effects and decay of dead woody material to demonstrate the dependence of different approaches and assumptions for carbon stock and carbon stock change estimates. For a given set of inventory data the reported change of carbon stock varied between 3.1 tonnes C ha−1 yr−1and 34.4 tonnes C ha−1 yr−1 for a 10-year period.Based on the available data set from a test area in the federal state of Salzburg (Austria) the effect of different scenarios for harvesting operations and mortality on reported carbon release was studied. The scenarios covered timber utilization at different points in time and two mortality rates (constant and exponential). A proportion of harvesting was assumed to remain inside the forest as logging residues and entered together with mortality a decay process. Two different lifetimes for decay (10 and 50 years) and constant and negative exponential decay rates were simulated. Those decisions affect the amount of carbon released considerably. For a 10-year period between 5% and 80% of the carbon content of dead woody material that accumulated within the period is released to the atmosphere. 相似文献
20.
ABSTRACT There is growing concern that public benefits from forests are underprovided in current forest management regimes and need to be increased through policy and economic measures that promote conservation. Ecological compensation is a type of institutional arrangement for the sustainable use of ecosystem services achieved by adjusting the distribution of costs and benefits among different stakeholders using economic measures. However, how to accurately and reasonably determine the compensation standard for ecological services has not been guided by scientific methods and theories. This study provides an estimation of the compensation standard for forest ecological services based on the forest multifunction evaluation and financial net present value analysis, and a case study was performed in Southwest China. The results showed that most forest types brought some economic loss to the managers but contributed great ecological benefits to the public when they were managed as ecological forests. It is crucial to incentivize forest managers to participate in voluntary conservation programs through ecological compensation. The results of this analysis can potentially guide sustainable forest management by both accurate quantification of the value of forest ecosystem services and an improved understanding of the costs of voluntary forest conservation schemes currently in use in many countries. 相似文献