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Discrepancies between targets and achievements in industrial forest production and export in Tanzania
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作者 E.F.NZUNDA 《Forestry Studies in China》 CAS 2012年第3期210-215,共6页
It is important to revisit our plans and compare what was ideally targeted against what was actually achieved in implementation. In comparing the achievements with targets, strengths or weaknesses of established strat... It is important to revisit our plans and compare what was ideally targeted against what was actually achieved in implementation. In comparing the achievements with targets, strengths or weaknesses of established strategies can be accepted or corrections implemented since a plan also outlines some strategies for achieving the targets set. In this study, achievements in production and export of industrial forest products, i.e., sawn wood, plywood, chipboard and fibreboard, paper and paperboard and industrial round wood, are compared against targeted figures for 1996 for Tanzania. Discrepancies were obtained by subtracting targeted from achieved values and expressed both as absolute and relative differences in terms of the targeted values, with a negative sign for pro- duction where achievements were less than targets and a positive sign when achievements were higher than targets. Values achieved ranged from 4%-100% of the targeted values, depending on the product, and were only higher than the targeted value for industrial round wood. Possible causes of the discrepancies are inefficiency of parastatal companies, low private investment, sub-maximal in- dustrial operation and plant inefficiencies. Discrepancies could also result from unrealistic data used in planning due to difficulty in data availability and poor intra- and inter-sectoral coordination. The implications of these discrepancies are low contributions of the wood-based industry to the national economy, increased import substitution of wood-based products, increased socio-economic and environmental degradation and decreased integrity in planning and policy making. 展开更多
关键词 TARGETS ACHIEVEMENTS industrial forest production and export Tanzania
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Exploring the Forest Cover Changes and Influential Factors of Dongsithouane National Production Forest Area, Savannakhet Province, Lao PDR
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作者 Souvanthone Douangphachachanh Chittana Phompila +5 位作者 Dipjoy Chakma Inta Chanthavong Maliphone Douangphachanh Puvadol Doydee Pengxiang Zhao Yuanchun Yu 《Journal of Data Analysis and Information Processing》 2024年第3期432-461,共30页
The Dongsithouane National Production Forest (DNPF) is one of the largest natural forest areas in Savannakhet, Lao PDR, which has been a vital support for the local community’s livelihood, Recently, significant chang... The Dongsithouane National Production Forest (DNPF) is one of the largest natural forest areas in Savannakhet, Lao PDR, which has been a vital support for the local community’s livelihood, Recently, significant changes in land use and land cover (LULC) have been observed in this area, leading to a reduction of natural forests. There were two separate methods of this study: firstly, to identify LULC changes across three different periods, spectral imagery from the Landsat 5 Thematic Mapper (TM) for the years 2001 and 2011, and the Landsat 8 Operational Land Imager (OLI) for 2021 were used as the primary data sources. The satellite images were preprocessed for various forest classes, including pretreatment of the top of atmosphere reflectance by using QGIS software’s semi-automatic classification plug-in (SCP), and ArcGIS was used for post-classification. A supervised classification approach was applied to the satellite images from 2001, 2011, and 2021 to generate diverse maps of LULC. Secondly, a household survey dataset was used to investigate influential factors. Approximately 220 households were interviewed in order to collect socio-economic information (including data on population growth, increased business activities, location of the area, agriculture land expansion, and need for settlement land). Household survey data was analyzed by using SPSS. Descriptive statistics, including frequency distributions and percentages, were applied to observe characteristics. Additionally, a binary logistic regression model was used to analyze the socioeconomic factors related to LULC change in DNPF. Key findings indicated a decline in natural forest areas within the study site. Specifically, both dry dipterocarp forest (−11.35%) and mixed deciduous forest (−0.18%) decreased from 2001 to 2021. The overall accuracy of the LULC maps was 94%, 86%, and 89% for the years 2001, 2011, and 2021 respectively. In contrast, agricultural land increased significantly by 155.70%, while built-up land, and water bodies increased by 65.54% and 35.33%, respectively. The results also highlighted a significant increase in construction land, up to 65.54%. Furthermore, the study found a correlation between agricultural expansion and a reduction of forest areas, along with an increase in built-up land along the forest areas’ boundaries. Timber exploitation and charcoal production also contributed to the decline in forest cover. The logistic regression model identified significant determinants of LULC change, including the area’s location, agricultural land expansion, increased business activity, and the need for settlement land. These factors have influenced the management of DNPF. Urgent sustainable management practices and actions, including forest ecosystem protection, village agricultural zoning, water source and watershed protection and public awareness, are required to preserve the forest areas of DNPF. 展开更多
关键词 Land Use/Land Cover Change QGIS SCP Socioeconomic Factor Dongsithouane National production forest Lao PDR
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No generality in biodiversity-productivity relationships along elevation in temperate and subtropical forest landscapes
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作者 Jiayun Zou Yahuang Luo +12 位作者 Rupert Seidl Dominik Thom Jie Liu Lisa Geres Tobias Richter Linjiang Ye Wei Zheng Liangliang Ma Jie Song Kun Xu Dezhu Li Lianming Gao Sebastian Seibold 《Forest Ecosystems》 SCIE CSCD 2024年第3期255-265,共11页
An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis sugges... An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis suggests that BPRs are stronger in stressful environments compared to more favorable conditions.However,there is limited knowledge regarding the variation of BPRs along elevational gradients and their generality across different landscapes.To study how BPRs change with elevation,we harnessed inventory data on 6,431 trees from152 plots surveyed twice in eight to ten year intervals in mountain forests of temperate Europe and subtropical Asia.We quantified the relationship between aboveground productivity and different biodiversity measures,including taxonomic,functional,and phylogenetic diversity.To elucidate the processes underlying BPRs,we studied the variation of different functional traits along elevation across landscapes.We found no general pattern of BPRs across landscapes and elevations.Relationships were neutral for all biodiversity measures in temperate forests,and negative for taxonomic and functional diversity in subtropical forests.BPRs were largely congruent between taxonomic,functional and phylogenetic diversity.We found only weak support for the stress-gradient hypothesis,with BPRs turning from negative to positive(effect not significant)close to the tree line in subtropical forests.In temperate forests,however,elevation patterns were strongly modulated by species identity effects as influenced by specific traits.The effect of traits such as community-weighted mean of maximum plant height and wood density on productivity was congruent across landscapes.Our study highlights the context-dependence of BPRs across elevation gradients and landscapes.Species traits are key modulating factors of BPRs and should be considered more explicitly in studies of the functional role of biodiversity.Furthermore,our findings highlight that potential trade-offs between conserving biodiversity and fostering ecosystem productivity exist,which require more attention in policy and management. 展开更多
关键词 Biodiversity-ecosystem functioning Climate mitigation Elevation gradients forest management forest productivity Functional traits Nature conservation Phylogenetic diversity
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Factors Impacting Benefits of Participatory Forest Management in Upper Imenti Forest, Meru County, Kenya
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作者 Josephine Kamene Musyoki Lamech Felix Mogambi Ming’ate +2 位作者 Joseph Muriithi Mbuvi Tito Edward Musingo Joram Kagombe 《Open Journal of Forestry》 2024年第3期183-196,共14页
This study focused on identifying factors affecting the benefits of Participatory Forestry Management (PFM) income generating activities in Upper Imenti Forest and whether they are dependent on status of participation... This study focused on identifying factors affecting the benefits of Participatory Forestry Management (PFM) income generating activities in Upper Imenti Forest and whether they are dependent on status of participation in forest management through membership of Community Forest Association (CFA) or not. Cross-sectional survey research design was applied for collecting quantitative data using a semi-structured questionnaire administered to 384 households stratified on the basis of PFM participation status. Qualitative data was collected through focused group discussions using a checklist and key informant interviews using an interview schedule. Using Statistical Package for Social Sciences version 25, Binomial regression with Wald Chi-square was analyzed to identify factors perceived to be significantly influencing benefits for PFM participants and Pearson Chi-square to compare factors perceived to be affecting PFM and non-PFM participants. CFA members participation in PFM was significantly and positively affected by benefits of PFM income generating activities and forest products accessed in the forest. Benefits linked to Plantation Establishment for Livelihood Improvement System (PELIS) for CFA members were significantly reduced by enforcement of moratorium policy since February 2018, diseases and pests, poor PELIS guideline adherence and animal damage. Benefits related to state forest access for firewood by the CFA members were negatively influenced by the moratorium policy. Diseases and pests affected benefits associated with bee keeping significantly. Comparing factors under different PFM participation status, crop production was significantly affected by policy changes, pest and diseases, animal damage and PELIS guideline adherence for CFA members than for Non-CFA members. Policy changes also affected the CFA members significantly in firewood collection and access to fodder in the state forest than the Non-CFA members. Hence, sustainable community participation in Upper Imenti Forest management requires: increasing PFM benefits, addressing factors reducing benefits and enhancing active participation of CFA members in PFM related decision-making processes. 展开更多
关键词 Participatory forest Management Community forest Association Sustainable Community Participation Access to forest Products Moratorium Policy Income Generating Activities
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Romanian legal management rules limit wood production in Norway spruce and beech forests 被引量:1
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作者 Olivier Bouriaud Gheorghe Marin +2 位作者 Laura Bouriaud Dominik Hessenmoller Ernst-Detlef Schulze 《Forest Ecosystems》 SCIE CSCD 2017年第1期1-11,共11页
Background: The quantitative impact of forest management on forests' wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation len... Background: The quantitative impact of forest management on forests' wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation length have seldom been directly quantified on landscape scale. Methods: Two sites of similar fertility but subject to contrasted forest management were studied with detailed inventories: one in Germany, the other in Romania, and compared with the respective national forest inventories. In Romania, regulations impose very long rotations, low thinnings and a period of no-cut before harvest. In contrast, tending and thinnings are frequent and intense in Germany. Harvests start much earlier and must avoid clear cutting but maintain a permanent forest cover with natural regeneration. While Germany has an average annual wood increment representative for Central Europe, Romania represents the average for Eastern Europe. Results: The lack of tending and thinning in the Romanian site resulted in twice as many trees per hectare as in the German site for the same age. The productivity in Romanian production forests was 20 % lower than in Germany despite a similar fertility. The results were supported by the data from the national forest inventory of each country, which confirmed that the same differential exists at country scale. Furthermore, provided the difference in rotation length, two crops are harvested in Germany when only one is harvested in Romania. The losses of production due to a lower level of management in Romania where estimated to reach 12.8 million m3.y-1 in regular mountain production forests, and to 15 million m3.y-1 if managed protection forest is included. Conclusions: The productivity of Picea and Fagus mountain forests in Romania is severely depressed by the lack of tending and thinning, by overly long rotations and the existence of a 25-years no-cut period prior to harvest. The average standing volume in Germany was 50 % lower than in Romania, but the higher harvesting rate resulted in more than doubling wood production. Considering the mitigation effects of climate change by forests, it emerges that the increase in standing volume of forests in Romania is smaller than the additional harvest in Germany which serves fossil fuel substitution. 展开更多
关键词 forest management forest productivity Legal rules Sylviculture forest Operations Wood resource
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Effects of harvest intensity on the marketable organ yield,growth and reproduction of non-timber forest products(NTFPs):implication for conservation and sustainable utilization of NTFPs 被引量:1
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作者 Ting Zhang Lizhong Yu +1 位作者 Yuan Man Qiaoling Yan 《Forest Ecosystems》 SCIE CSCD 2021年第4期755-764,共10页
Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic... Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of NTFPs.Harvest intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and dynamics.Therefore,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study objects.Aiming to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive performances.Results:The biomass growth rates of marketable organ and plant growth of A.senticosus under light harvest intensity treatment were significantly higher than those under other harvest intensities.The plant height growth and 1000-seed weight of A.elata under severe harvest intensity treatment were significantly lower than those under control treatment.Conclusions:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of A.senticosus and A.elata,respectively.These findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs species.Consequently,the local residents or communities can improve their income while ensure the sustainable development of wild NTFPs. 展开更多
关键词 Araliaceae family Non-timber forest products Sustainable utilization Harvest intensity Plant regeneration Marketable organ yield
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Mushroom Production as an Alternative for Rural Development in a Forested Mountainous Area 被引量:1
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作者 José A.BONET José R.GONZáLEZ-OLABARRIA Juan MARTíNEZ DE ARAGóN 《Journal of Mountain Science》 SCIE CSCD 2014年第2期535-543,共9页
Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining ... Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining reliable productivity data, minimizing their true potential as contributor to rural economies. Mushroom yield models based on large data series from Pinus forest ecosystems in the region of Catalonia(Spain), combined with data from the Spanish National Forest Inventory allow us to estimate the potential mushroom productivity by forest ecosystems. The results of 24,500 tons/yr of mushrooms of which 16,300 tons are classified as edible and 7,900 tons are commonly marketed demonstrate the importance of mushroom productions in Catalonian pine forests, mostly located in mountainous areas where the development of agricultural activities is limited. Economic mushroom value is estimated at 48 million € for the edible mushroom and 32 million € for those corresponding to marketable yields, confirming the potential of this non-wood forest product. These production results and corresponding economic values provide a basis for the incorporation of wild mushrooms as significant non-wood forest products in the development of forest policies in mountainous areas. 展开更多
关键词 Non-wood forest products Mushroom models National forest Inventory Economic value Mushroom potential estimation
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Diversity and production in an Afromontane Forest 被引量:6
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作者 Klaus v.Gadow GongQiao Zhang +2 位作者 Graham Durrheim David Drew Armin Seydack 《Forest Ecosystems》 SCIE CSCD 2016年第4期275-286,共12页
Background:This contribution evaluates the effect of forest structure and tree species diversity on plot productivity and individual tree growth in the unique Knysna forests in Southern Africa using mapped tree data ... Background:This contribution evaluates the effect of forest structure and tree species diversity on plot productivity and individual tree growth in the unique Knysna forests in Southern Africa using mapped tree data from an observational study that has been re-measured over a period of 40 years.Methods:The effects of tree species diversity and forest structure on tree growth and forest production are evaluated on three levels of resolution:a) the forest community(canopy,sub-canopy species),b) the subplots(number of trees per ha,skewness of the diameter distribution,diameter coefficient of variation) and c) the immediate neighborhood of selected reference trees("Mingling","Dominance",Aggregation" and "Size Variation").Results:An analysis of the community level identified two distinct clusters,one including dominant/canopy species with the highest growth rates and a greater variation of growth,and another cluster which includes the remaining subcanopy species which have a smaller maximum size and lower rates of growth.The area-based structure variables on plot level have a highly significant effect on total basal area growth.However,the effects of forest density and species richness on productivity were not straight forward.Maximum basal area production of about 0.75 m^2/ha/year is achieved at medium levels of richness(around 20 species per ha) and medium levels of density(around 30 m^2/ha basal area) using percentile regression estimates.The relative "Dominance" of a selected reference tree had a highly significant effect on individual tree growth on all investigated species.Other neighbourhood structure variables were only occasionally significant or not significant at all.Conclusion:This contribution presents a new theoretical framework for analysing natural forests that includes community,plot and neighborhood variables of forest structure and diversity,and a first specific analysis of the structure and dynamics of the Knysna Afromontane Forest,based on a unique set of longterm observations.The species-area(SAR) model developed in this study,represents a new general approach that can be used to derive a common standard of tree species diversity for different plot sizes,the species richness per hectare. 展开更多
关键词 canopy neighborhood forests richness basal straight productivity occasionally remaining tropical
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Carbon emission efficiency of forest processing industries in China
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作者 GUAN Zhi-jie Yahaya Idris MUSA +1 位作者 ZHANG Ya-xin GUO Zhi-yuan 《Ecological Economy》 2023年第3期217-232,共16页
This paper uses an input-output table of China's provinces(2007-2016) to measure carbon emissions of these industries.It employs a Malmquist-Luenberger(ML) index with expected and undesired outputs,and an absolute... This paper uses an input-output table of China's provinces(2007-2016) to measure carbon emissions of these industries.It employs a Malmquist-Luenberger(ML) index with expected and undesired outputs,and an absolute β convergence and a conditional β convergence model,to conduct an in-depth analysis of dynamic changes and spatial convergence.Carbon emission efficiency of forest processing industries in 25 regions,including Shanghai,Chongqing,Zhejiang,and Jiangsu are increasing,whereas those of Tianjin,Liaoning,Heilongjiang,and Tibet are decreasing.The main contributing factors of carbon emission efficiency in three major regions vary over time.Further,carbon emission efficiency in the eastern,central,and western regions all have absolute β convergence and conditional β convergence,indicating that different regions are developing toward their own goals and industry,yet regions with lower efficiency are catching up with those where with more efficient strategies in place.Finally,this paper proposes according recommendations. 展开更多
关键词 input-output model ML index CONVERGENCE carbon emission efficiency forest industry production
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The Harvesting of the Endangered Palm Euterpe edulis in the Brazilian Atlantic Forest: The Case of Linear Canopy Openings
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作者 Pablo José Francisco Pena Rodrigues Mariana de Andrade Iguatemy Talita Reis 《Journal of Geoscience and Environment Protection》 2023年第12期151-162,共12页
The palm Euterpe edulis was historically very exploited by humans and even today, many individuals are cut down by collectors to harvest the edible palm hearts. The ecological aspects of this anthropogenic pressure an... The palm Euterpe edulis was historically very exploited by humans and even today, many individuals are cut down by collectors to harvest the edible palm hearts. The ecological aspects of this anthropogenic pressure and its related effects are poorly understood. Here we investigate if linear canopy openings in a fragment of Brazilian Atlantic Forest can cause edge effects and facilitate predatory harvesting by humans. We sampled in Tinguá Biological Reserve (Southeastern Brazil) native palm populations at forest edges adjacent to two linear canopy openings, and in the forest interior far from any edge. Our 8-year monitoring showed that the linear canopy openings negatively affected the palm populations reducing its density and regeneration mainly on edges, but no local extinction was observed. Thus, the direct human impact from harvesting, adverse survival conditions on edges and interspecific competition causes population declines with no local extinction, so this suggests that E. edulis may resist even under strong anthropogenic pressure. 展开更多
关键词 EXTINCTION EXPLOITATION forest Product Species Survival Sustainability
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The Influence of forest certification on forest product trade 被引量:2
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作者 郑仰南 蒋敏元 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期316-318,338,共3页
Forest certification is considered to be complementary to forest management policies and takes a significant effect on forest product trade. In recent decade, it has been followed with interest and approved by governm... Forest certification is considered to be complementary to forest management policies and takes a significant effect on forest product trade. In recent decade, it has been followed with interest and approved by governments and forestry de-partments in the world. This paper analyzes the influence of forest certification on forest product trade in the world, including the interest in certification in exporting countries and importing countries, trade flow and business competition, and the demands for Certified Forest Products (CFPs) and also discusses the influence of forest certification on forest product trade in China. 展开更多
关键词 forest Certification Certified forest Products forest Product Trade
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Calculation of forest potential productivity for Tianshan forest region
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作者 罗明灿 覃家理 李虎 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期73-74,共3页
Forest Potential Productivity (FPP) of 8 counties in Tianshan was cal culated, and the potential timber output of these counties was analyzed with Mia mi Model and Thornthwaite Memorial Model. Research results showed ... Forest Potential Productivity (FPP) of 8 counties in Tianshan was cal culated, and the potential timber output of these counties was analyzed with Mia mi Model and Thornthwaite Memorial Model. Research results showed that annual av erage output of present stand in Tianshan Forest Region was 3.7 m3/(hm2. a), whi ch reached only 49% of average FPP. 展开更多
关键词 forest potential productivity Miami Model Thorthwaite Memorial Model OUTPUT
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Study on Sonneratia apetala productivity in restored forests in Leizhou Peninsula, China 被引量:1
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作者 韩维栋 高秀梅 Edwin Teunissen 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第4期229-234,276,共7页
The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage... The exotic Sonneratia apetala in Leizhou Peninsula, has shown outstanding fast-growing ability in restored mangrove forests, at the middle and high tide intertidal zone, with year-round fresh water input from drainage. By setting plot and selecting standard tree, investigation and measurement on height growth, diameter growth, biomass, productivity, and so on, were made in a S. apetala plantation at age of six at Lanbei, Fucheng, Leizhou Peninsula in May 2001. The investigating results showed that the mean annual height growth of plantation was 2.03 m and mean annual growth of diameter at breast height (DBH) was 2.35 cm. There exists a significant correlation between the diameter at ground surface (DGS) and DBH. The average biomass of a single standard tree in dry weight was 95.647 kg/m2. A ratio of above-ground biomass to under-ground biomass was 1.60. The stand biomass of unit area was 22.955 kg/m2, singletree wood volume was 88.23 dm3, and the annual wood volume productivity (PA) of the same year was 0.407. The forest energy accumulation was 424.851 MJ/m2, with annual solar energy fixing rate of 40.68 ×10-7%. It is concluded that S. apetala species had characteristics of outstanding high biomass accumulation and could be used as coastal planting tree species in southern China. 展开更多
关键词 Sonneratia apetala MANGROVE Biomass Leizhou Peninsula Study on Sonneratia apetala productivity in restored forests in Leizhou Peninsula China HAN Wei-dong GAO Xiu-mei (Zhanjiang Ocean University Zhanjiang 524088 Guangdong P.R. China)
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The growth and production modeling of individual trees of Eucalyptus urophylla plantations
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作者 Joao Victor Nobre Carrijo Ana Beatriz de Freitas Ferreira +4 位作者 Marcela Costa Ferreira Mario Cesar de Aguiar Eder Pereira Miguel Eraldo Aparecido Trondoli Matricardi Alba Valeria Rezende 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第5期1663-1672,共10页
Individual tree models(ITMs)are classified as growth and production models for projecting current and future forest stands.ITMs are more complex than other growth and production models,show a higher level of detail an... Individual tree models(ITMs)are classified as growth and production models for projecting current and future forest stands.ITMs are more complex than other growth and production models,show a higher level of detail and,consequently,produce a better modeling resolution.However,the accuracy and efficiency of ITMs have not been properly assessed to date.In this study,we estimated the growth in height,diameter,and individual tree volume of a Eucalyptus urophylla plantation by applying an ITM.We used a continuing forest inventory dataset in which 1554 individual trees within 29 permanent plots were measured in the field over a 6-year period(24 to 72 months).Each individual tree volume was estimated for future tree age.To achieve this,we adjusted the model to predict the height and diameter growth,and the probability of mortality as a function of the competition index.The ITM accuracy was assessed based on the analysis of variance results and,subsequently,the multiple mean comparison test at the 5%significance level.The tree volumes predicted by the ITM for the forest stand aged 72 months,beginning at ages 24,36,48,and 60 months,were compared to the field measured tree volume acquired from the 72-month forest inventory that was used as the reference age.Estimated and observed tree volumes were similar when the estimation was based on the 48-month forest plots.These results might help to reduce financial costs of forest inventory because the ITM produces accurate future predictions of forest stand stocks.Our estimated ITM for Eucalyptus plantations using measurement intervals up to 2 years is recommended because it significantly reduced the projected volume discrepancy compared to the field measurements. 展开更多
关键词 Competition index forest production forest site Simulation models Tree mortality
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Soil Attributes and Production of Eucalyptus in Monoculture and Silvopastoral Systems in the North of Minas Gerais, Brazil
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作者 Pedro Henrique Lopes Santana Leidivan Almeida Frazao +2 位作者 Leonardo David Tuffi Santos Luiz Amaldo Femandes Regynaldo Arruda Sampaio 《Journal of Agricultural Science and Technology(B)》 2016年第6期361-370,共10页
The objective of this study was to evaluate the chemical and physical attributes of soil, and the productivity of Eucalyptus cultivated in monoculture and silvopastoral systems. The experiment started in 2009 and eval... The objective of this study was to evaluate the chemical and physical attributes of soil, and the productivity of Eucalyptus cultivated in monoculture and silvopastoral systems. The experiment started in 2009 and evaluated the following four systems: native vegetation system (Cerrado), a degraded pasture, a Eucalyptus urograndis monoculture (E. urophylla x E. grandis) and a silvopastoral system (E. urograndis combined with Brachiaria brizantha cv. "Marandu"). The experimental design used was completely randomized. In each system, four soil samples were collected from the 0-20 cm depth layer, and the chemical and physical attributes of the soil were evaluated. The diameters of all Eucalyptus trees at 1.30 m above the ground as well as the total height were measured. Subsequently, the trees dimensions were measured and their individual volumes obtained by applying the Smalian formula. The correlation between the parameters for Eucalyptus production and soil attributes was established using the Pearson's correlation coefficient method. The planting of Eucalyptus in monoculture and silvopastoral systems contributed to the improvement of the soil's chemical and physical attributes, which indicates the potential of these systems for recovery of degraded pastures. The silvopastoral system yielded the highest average volume of wood per tree (0.2228 m^3), with a productivity of 111.4 m^3/ha. The Eucalyptus monoculture yielded 0.1895 m^3 per tree and 315.71 m^3/ha due to the higher density of the crop. The growth and productivity of Eucalyptus showed highly correlation with the soil attributes, thus suggesting that well-managed crops are an indicator of the soil quality recovery. 展开更多
关键词 Diameter at breast weight forest-livestock integration system forest production soil quality.
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Past,present and future of industrial plantation forestry and implication on future timber harvesting technology 被引量:4
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作者 Andrew McEwan Enrico Marchi +1 位作者 Raffaele Spinelli Michal Brink 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第2期339-351,共13页
Plantation forests are established,and expanding,to satisfy increasing global demand for timber products.Shifting societal values,such as safety,productivity,environmental,quality and social are influencing the planta... Plantation forests are established,and expanding,to satisfy increasing global demand for timber products.Shifting societal values,such as safety,productivity,environmental,quality and social are influencing the plantation forestry sector.This is primarily driven through an ever increasing world population,which in turn influences the way nations view the value systems by which they live.More people require more resources-also forest products.Also,the availability of information is influencing the pace of technological development.These changes could result in a difference in the management of plantations that could affect the forest engineering systems of the future.This review aimed to summarize the current status of plantation forests;summarize future developments and possible scenarios in forest plantation management for the various products;and assess whether these developments in a plantation environment could affect the harvesting systems used.Factors influencing the form of plantations include the type and nature of the plantation owner;the change in demand for different and new forest products;climate change factors,including the use of biomass for energy,carbon sequestration and trading;ecosystem services and other products and services;and sustainability certification of forest management.The impact and influence of these factors were summarised into a series of key drivers that will influence the technology used in harvesting machines,as well as the choice of harvesting machines,systems and methods.These drivers were the effect of variations in tree size,the expansion of plantation areas onto more difficult terrain,diversity in plantation design,increased attention towards site impacts and the increased use of biomass for energy.Specific information is provided regarding how the harvesting systems could be affected. 展开更多
关键词 Plantations forest products Biomass Harvesting system MECHANIZATION Trends TECHNOLOGY
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National Forest Inventories capture the multifunctionality of managed forests in Germany 被引量:3
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作者 Nadja K.Simons María R.Felipe-Lucia +26 位作者 Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning Ernst-Detlef Schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber Tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser 《Forest Ecosystems》 SCIE CSCD 2021年第1期50-68,共19页
Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forest... Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem services.However,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services.Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem services.We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data.Results:Looking at the potential supply of ecosystem services,we found trade-offs(e.g.between both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(e.g.for temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in Germany.No single forest type provided all ecosystem services equally.Some ecosystem services showed comparable levels across forest types(e.g.decomposition or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(e.g.phosphorous availability or cover of edible plants)or tree species composition(e.g.potential nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions.However,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species.Conclusions:Our results show that forest multifunctionality is limited to subsets of ecosystem services.The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level,when stands of complementary forest types are combined.These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales. 展开更多
关键词 Ecosystem processes and services forest management Structural diversity Tree species composition Trade-offs and synergies forest productivity
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A review on the use of non-timber forest products in beauty-care in Bangladesh 被引量:2
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作者 Sayma Akhter Md. Abdul Halim +3 位作者 Md. Shawkat Islam Sohel Swapan Kumar Sarker Mohammad Shaheed Hossain Chowdhury Sanjay Saha Sonet 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期72-78,共7页
This review describes the non-timber forest products (NTFPs) used for different aspects of beauty-care in Bangladesh on the basis of extensive literature survey. The diverse plant species, including used parts and u... This review describes the non-timber forest products (NTFPs) used for different aspects of beauty-care in Bangladesh on the basis of extensive literature survey. The diverse plant species, including used parts and using patterns for hair care, facial treatments and body care, were summarized in 13 tables. This paper accumulate the scattered knowledge regarding the use of plants in beauty-care in Bangladesh, to draw the extent of use of NTFPs in health care and to record the knowledge for assessing the possibilities of further implementation in herbal cosmetics industries. The structured knowledge can be used in policy making process for sustainable management of these valuable NTFPs leading to the conservation of the country's biological diversity. It is suggested that intensive field level research is necessary for securing sustainability of NTFPs. 展开更多
关键词 beauty care non-timber forest products (NTFPs) BANGLADESH
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Diversity of non-timber forest products in Cachar District, Assam, India 被引量:1
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作者 Shovan Dattagupta Abhik Gupta Manoranjan Ghose 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期463-470,共8页
We identified 67 and 21 NTFP-yielding plant and animal species, respectively, in a reserve forest in Cachar district of Assam. We recorded globally threatened species listed by IUCN as Critically Endangered (plant sp... We identified 67 and 21 NTFP-yielding plant and animal species, respectively, in a reserve forest in Cachar district of Assam. We recorded globally threatened species listed by IUCN as Critically Endangered (plant species Dipterocarpus turbinatus), Vulnerable (plant species Aquillaria malaccensis), Endangered (animal species Hoolock hoolock, Indotestudo elongata and Manis pentadactyla), and Vulnerable (animal species Nilssonia hurum and Rusa unicolor). The whole plant or animal and/or their various parts were used as food or medicine, in house construction, magico-religious activities and others. While some NTFPs were harvested throughout the year, others were harvested seasonally. A comprehensive NTFP policy, along with scientific measures for regen- eration, restoration and augmentation of NTFP-yielding plants and animals, would help in addressing the conflicting demands of conservation and livelihood in the forests of this area. 展开更多
关键词 Non-timber forest product (NTFP) lndo-Burma biodiversity hotspot ASSAM IUCN red list DIVERSITY threatened taxa
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Population distribution and threats to sustainable management of selected non-timber forest products in tropical lowland rainforests of south western Nigeria 被引量:1
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作者 Jimoh S.O. Amusa T.O. I.O. Azeez 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期75-82,共8页
Uncontrolled harvesting of non-timber forest products (NTFPs) poses a serious risk of extermination to several of these species in Nigeria. Yet, there is a paucity of information on the distribution, population stat... Uncontrolled harvesting of non-timber forest products (NTFPs) poses a serious risk of extermination to several of these species in Nigeria. Yet, there is a paucity of information on the distribution, population status and sustainable management of NTFPs in most of the tropical lowland rainforests. We, therefore, assessed the population, distribution and threats to sustainable management of NTFPs within the tropical lowland rainforests of Omo and Shasha Forest Reserves, south western Nigeria. Data were obtained through inventory surveys on five top priority species including: bush mango (Irvingia gabonensis (Aubry-Lecomte ex O’Rorke) Baill), African walnut (Tetracarpidium conophorum (Mull. Arg.) Hutch. & Dalziel syn. Plukenetia conophora), chew-stick (Massularia acuminata (G. Don) Bullock), fever bark (Annickia chlorantha Setten & P.J.Maas syn. Enantia chloranta) and bush pepper (Piper guineense Schumach. & Thonn.). Purposive and stratified random sampling techniques were used for the inventory. Each forest reserve was stratified into three, viz: less disturbed natural forest (for areas that have been rested for at least ten years), recently disturbed natural forest (for areas that have suffered one form of human perturbation or the other in the last five years), and plantation forest (for areas carrying forest plantation). Data were collected from eighteen 10 m × 500 m belt transects located in the above strata. The species were generally fewer in both plantation and recently disturbed natural forest than the less disturbed natural forest, suggesting that forest disturbances (habitat modification) for other uses may have an effect on the occurrence and densities of the NTFPs. Exceptions to this trend were found for P. guineense and T. conophorum, which were fairly common in both plantation and recently disturbed natural forest. Among three tree NTFP species (i.e. I. gabonensis, M. acuminata and A. chlorantha), only I. gabonensis showed a significant difference in overall DBH size classes for both reserves (t=?2.404; df =21; p=0.026). Three tree NTFP species in both reserves further showed differences from the regular patterns of distribution of trees. The fairly regular reverse J-shaped size class distribution observed for M. acuminata in the study sites, however, suggests a recuperating population. In general, destructive harvesting of species, logging operations, low population size, narrow distribution ranges and habitat degradation are the major threats to the population of NTFPs in the study area. The implications of our findings for sustainable management of NTFPs in the study area are discussed and recommendations are made for a feasible approach towards enhancing the status of the species. 展开更多
关键词 Tropical rainforest non-timber forest products (NTFP) population density distribution forest management
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