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基于Random Forest和UHPLC-QTOF-MS^(E)对不同来源龟甲基原的鉴定
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作者 王献瑞 张佳婷 +5 位作者 张宇 李明华 郭晓晗 荆文光 程显隆 魏锋 《中国药事》 CAS 2024年第9期1008-1019,共12页
目的:基于超高效液相色谱串联四极杆飞行时间质谱(UHPLC-QTOF-MS^(E))分析并经数字量化处理,结合随机森林(Random Forest,RF)算法构建数据辨识模型,以实现中华草龟、巴西龟、台湾龟、鳄鱼龟、鳖甲基原的数字化鉴定。方法:经样品预处理后... 目的:基于超高效液相色谱串联四极杆飞行时间质谱(UHPLC-QTOF-MS^(E))分析并经数字量化处理,结合随机森林(Random Forest,RF)算法构建数据辨识模型,以实现中华草龟、巴西龟、台湾龟、鳄鱼龟、鳖甲基原的数字化鉴定。方法:经样品预处理后,对不同来源、不同批次的龟甲进行UPLC-QTOF-MS^(E)分析,并以混合样品为基准进行峰位校正、提取并经量化处理,获取反映多肽离子信息的精确质量数-保留时间数据对(Exact Mass Retention Time,EMRT)。然后基于信息增益率的特征筛选获取重要多肽离子信息,结合随机森林(RF)算法进行数据建模,同时基于内部交叉验证中的准确率(Acc)、精确率(P)、曲线下面积(AUC)等参数进行模型评价。最后基于最优模型进行龟甲基原的鉴定验证分析。结果:基于信息增益率的特征筛选,得到71个特征多肽信息,建立的RF模型具有优秀的辨识效果,准确率、精确率以及AUC均大于0.950且外部鉴定验证的正确率为100.0%。结论:基于UHPLC-QTOF-MS^(E)分析,并结合RF算法能够高效准确地实现不同来源龟甲基原的数字化鉴定,可为龟甲的质量控制及基原考证提供参考和帮助。 展开更多
关键词 龟甲 基原鉴定 机器学习 随机森林 超高效液相色谱串联四极杆飞行时间质谱
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Ecosystem service multifunctionality of mixed conifer-broad-leaved forests under climate change and forest management based on matrix growth modelling
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作者 Xue Du Xiangdong Lei +3 位作者 Xiao He Jie Lan Hong Guo Qigang Xu 《Forest Ecosystems》 SCIE CSCD 2024年第5期743-757,共15页
Climate change and forest management are recognized as pivotal factors influencing forest ecosystem services and thus multifunctionality.However,the magnitude and the relative importance of climate change and forest m... Climate change and forest management are recognized as pivotal factors influencing forest ecosystem services and thus multifunctionality.However,the magnitude and the relative importance of climate change and forest management effects on the multifunctionality remain unclear,especially for natural mixed forests.In this study,our objective is to address this gap by utilizing simulations of climate-sensitive transition matrix growth models based on national forest inventory plot data.We evaluated the effects of seven management scenarios(combinations of various cutting methods and intensities)on the future provision of ecosystem services and multifunctionality in mixed conifer-broad-leaved forests in northeastern China,under four climate scenarios(SSP1-2.6,SSP2-4.5,SSP5-8.5,and constant climate).Provisioning,regulating,cultural,and supporting services were described by timber production,carbon storage,carbon sequestration,tree species diversity,deadwood volume,and the number of large living trees.Our findings indicated that timber production was significantly influenced by management scenarios,while tree species diversity,deadwood volume,and large living trees were impacted by both climate and management separately.Carbon storage and sequestration were notably influenced by both management and the interaction of climate and management.These findings emphasized the profound impact of forest management on ecosystem services,outweighing that of climate scenarios alone.We found no single management scenario maximized all six ecosystem service indicators.The upper story thinning by 5%intensity with 5-year interval(UST5)management strategy emerged with the highest multifunctionality,surpassing the lowest values by more than 20%across all climate scenarios.In conclusion,our results underlined the potential of climate-sensitive transition matrix growth models as a decision support tool and provided recommendations for long-term strategies for multifunctional forest management under future climate change context.Ecosystem services and multifunctionality of forests could be enhanced by implementing appropriate management measures amidst a changing climate. 展开更多
关键词 Multifunctional forest management THINNING Transition matrix growth model Carbon sink timber production
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Export Competitiveness and Sustainable Development of the Ukrainian Timber Industry
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作者 Anastasiia Shapiro 《Open Journal of Applied Sciences》 2024年第10期2777-2789,共13页
This paper conducts a comprehensive analysis of the export dynamics within the Ukrainian timber industry, emphasizing its pivotal role in the national economy. The study begins by outlining the research objectives, co... This paper conducts a comprehensive analysis of the export dynamics within the Ukrainian timber industry, emphasizing its pivotal role in the national economy. The study begins by outlining the research objectives, context, and innovative methodologies, setting the stage for a deep dive into the theoretical underpinnings of sustainable and competitive trade. It explores Ukraine’s rich forest biodiversity across varied vegetation zones and its geopolitical significance. Detailed evaluations of forest resource management, policy frameworks, and institutional support form the core of the analysis. Challenges such as imbalanced export structures and legal inconsistencies are critically examined. The research employs trade gravity models and competitive indicators like the Revealed Comparative Advantage (RCA) and Market Share (MS) to assess factors influencing exports and to forecast potential growth areas. The findings inform strategic recommendations aimed at enhancing export capacity through market diversification, brand development, and legal stability. The conclusion highlights the need for strategic interventions to harness Ukraine’s timber resources sustainably, balancing economic gains with environmental stewardship. 展开更多
关键词 Ukrainian timber Industry export Dynamics export Competitiveness Sustainable Trade forest Resource Management
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Quantitative and financial evaluation of non-timber forest products(case study:Zemkan basin forests,West of Iran) 被引量:3
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作者 Sohrab Moradi Soleiman Mohammadi Limaei +1 位作者 Peter Lohmander Mehrdad Khanmohammadi 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期371-379,共9页
Although Zagros forests in western Iran lack industrial timber value due to the severe climate and socioeconomics problems, non-timber products are of great value and importance due to their high economic potential an... Although Zagros forests in western Iran lack industrial timber value due to the severe climate and socioeconomics problems, non-timber products are of great value and importance due to their high economic potential and also their potential to improve the welfare of forestdwelling and forest-fringe villagers. This study was done in the forests of the Zemkan basin, an important part of central Zagros forests, Iran, to recognize the non-timber forest products(NTFPS), investigate their potential economic value and role in people's livelihood. Data, collected using forest cruising, participatory observations, interviews with indigenous and local persons and experts, identified wild pistachio resin, wild pistachio fruit, oak fruit and oak syrup(Shokeh manna) among the non-timber products in this basin with total potential harvestable NTFPs of 77.16,771.602, 13248.68, and 1324.868 tons per year,respectively. The economic rent from NTFPs is 33 US$/ha/year and its total expected values with consideration of real interest rate when the exploiter invests the capital in the bank(6.4 %) and when money is borrowed from the bank to execute the incorporated projects(8.4 %) are $516/ha and $393/ha, respectively. Furthermore, families' economic share from potential profit of NTFPs is annually$601 per household. In addition wild pistachio resin has the highest share of the total potential profit of NTFPs and its equal to 51 % of the total of potential profit of NTFPs.Therefore, it is suggested that decisions be made to increase the infrastructure and strengthen the local selling market to enhance the cash income from NTFPs. Forest participatory management practices are suggested to organize and improve traditional use of the forests. 展开更多
关键词 timber forests profit resin annually recognize fringe income household execute
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基于ECA注意力机制改进的EfficientNet-E模型的森林火灾识别
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作者 周浪 樊坤 +1 位作者 瞿华 张丁然 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第2期42-49,共8页
火灾的发生给社会带来了巨大损失,森林火灾防治任务日益迫切,而全球变暖的趋势使得这一问题更加复杂。深度学习在各行各业发挥着重要作用,大量模型也被不断地设计和提出,且模型改进的方式多种多样。文中提出了EfficientNet-E模型,它利... 火灾的发生给社会带来了巨大损失,森林火灾防治任务日益迫切,而全球变暖的趋势使得这一问题更加复杂。深度学习在各行各业发挥着重要作用,大量模型也被不断地设计和提出,且模型改进的方式多种多样。文中提出了EfficientNet-E模型,它利用更为先进的ECA模块(高效通道注意力模块)来替换EfficientNet模型中的SE模块,通过增强注意力机制性能提升模型的性能。相较于SE模块,ECA模块更好地保留了传输中的信息,使得数据特征在传输过程中保留更充分,从而能够优化模型。为验证EfficientNet-E模型的性能,以及EfficientNet设计思想在森林火灾识别问题上相较于传统模型的优势,文中选取了经典模型中的代表——ResNet和DenseNet作为对照参考,并结合EfficientNet和EfficientNet-E进行了相关实验。实验选用3303张森林火灾、非火灾和烟雾图片。多轮试验结果显示,EfficientNet-E在识别森林火灾数据上的效果要好于常规的经典深度学习模型,且相较于原始EfficientNet的平均准确率(89.28%),EfficientNet-E的平均准确率(90.04%)有所提升,标准差更小,训练稳定性也更好,从而证实了改进后的EfficientNet-E性能更加优良。 展开更多
关键词 深度学习 图像识别 森林火灾 efficientNet-e 注意力机制
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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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Market analysis for timber and forest products in China
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作者 陆文达 王冬香 凌楠 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第2期124-126,共3页
This paper introduces the general condition of forestry resources of China and the demand and supply of timber and forest products. The market for timber and forest producls has borne dual pressure because of the popu... This paper introduces the general condition of forestry resources of China and the demand and supply of timber and forest products. The market for timber and forest producls has borne dual pressure because of the population explosion and growth of the domestic economy. A major contemporary strategy for sustainable forestry includes the promotion of the Forest Products Industry (FPI), the substitution of other materials for timber,and the encouragement of imports of timber and forest products. The author analyzes the effect of these policies on the market for timber and forest products. In addition, the difficulties encountered by most mid-to large -scale state- owned forest enterprises during the transition from a centrally-planned economy to a market economy are examined. Finally, the author points out the countermeasures and means for reform of these old forest enterprises with a view toward future prosperity of the market for timber and forest products. 展开更多
关键词 timber forest PRODUCTS WOOD based PANeLS (WBP) PULP & PAPeR forest PRODUCTS Industry (FPI)
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Assessing forest sustainability trajectory with temporal changes in timber output and ecological reserve: the case of China
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作者 Jianwei Bai Yang Zhao +1 位作者 Longyu Shi Fengri Li 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第1期171-176,共6页
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... 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 between1950 and 2013. Data were acquired mainly from forest inventory statistics published by China’s Forestry Administration between the 1970 s and 2013. I Information from the 1950 s 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 1950 s and late 1970 s, 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. 展开更多
关键词 ecological vigor forest assessment Natural forests Sustainable forestry timber
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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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Rate of timber production in a tropical rainforest ecosystem of Southwestern Nigeria and its implications on sustainable forest management
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作者 V.A.J.Ade-kunle A.O.Olagoke L.F.Ogundare 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期225-230,I0007,I0008,共8页
Timber harvesting data are very essential for sustainable management of forest resources.These data are very scarce in developing countries.Therefore,we collected and analyzed data on the rate of timber production of ... Timber harvesting data are very essential for sustainable management of forest resources.These data are very scarce in developing countries.Therefore,we collected and analyzed data on the rate of timber production of the free areas and the forest reserves in Ondo State,Nigeria.The data collected from the State Department of Forestry's official records,annual reports and files were on the species,volume and number of different economic timbers exploited on monthly basis between 2003 and 2005.Analyses were done with the student t-test and one-way analysis of variance.Results reveal that the highest numbers of species,families and stems were exploited in the free areas when compared with what was exploited from the reserves for the three-year period.However,the total volume of trees removed from the reserves was significantly higher(p〈0.05) than what was removed from the free areas.A total 60 different indigenous hardwood species in 25 families were exploited from the free areas,and 57 in 23 families from the reserves.The total number of stems exploited from the forest ecosystem of Ondo state during the three-year period stood at 111377 with an estimated volume of 295089.67 m^3.While the mean number of stems and volume exploited per annum is 37125 and 98363.22 m^3,respectively.The monthly average number of stems and volume is 3094 and 8196 m^3,respectively.The t-test results show that there were significant differences(p〈0.05) in number of stems and volume removed from the free areas and the reserves.The ANOVA results reveal a significant increase(p〈0.05) in logging activities between the years of 2003 and 2004 but there was a decline in year 2005.This trend reveals that economic timber species were disappearing from the forests and the ecosystem was seriously disturbed during logging activities.Principles for achieving the goals of sustainable forest management(SFM) and urgent conservation measures to mitigate the consequences of forest degradation were suggested. 展开更多
关键词 conservation measures forest estate illegal logging sustainable forest management timber harvesting
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Forestland prediction of China based on forest ecosystem services for the first half of 21st century
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作者 董仁才 陈春娣 +1 位作者 邓红兵 赵景柱 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第3期181-186,共6页
A new model was developed to predict forestland demand of China during the years of 2010-2050 in terms of the concept of forest ecosystem services. On the basis of the relationship between forest ecosystem services an... A new model was developed to predict forestland demand of China during the years of 2010-2050 in terms of the concept of forest ecosystem services. On the basis of the relationship between forest ecosystem services and classified forest management, we hypothesized that the ecological-forest provides ecological services, whereas commercial-forest supplies wood and timber production, and the influences of the growth of population, social-economic development target, forest management methods and the technology changes on forest resources were also taken into account. The prediction reveals that the demand of total forestland of China will be 244.8, 261.2 and 362.2 million ha by the year 2010, 2020 and 2050, respectively. The results demonstrated that China will be confronted with a shortage of forest resources, especially with lack of ecological-oriented forests, in the future. It is suggested that sustainable management of forest resources must be reinforced and more attention should be drown no enhancing the service function of forest ecosystem. 展开更多
关键词 forest resources forest ecosystem services forestland prediction commercial forest ecological forest timber demand ecological demand
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A comparative assessment on regeneration status of indigenous woody plants in Eucalyptus grandis plantation and adjacent natural forest 被引量:4
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作者 Shiferaw Alem Tadesse Woldemariam 《Journal of Forestry Research》 SCIE EI CAS CSCD 2009年第1期31-36,共6页
Diversity, density and species composition of naturally regenerated woody plants under Eucalyptus grandis plantation and the adjacent natural forest were investigated and compared. Twenty plots, with an area of 20 m &... Diversity, density and species composition of naturally regenerated woody plants under Eucalyptus grandis plantation and the adjacent natural forest were investigated and compared. Twenty plots, with an area of 20 m × 20 m for each, were established in both of E. grand& plantation and adjacent natural forest, independently. In each plot, species name, abundance, diameter and height were recorded. Numbers of seedling were collected in five sub-plots (4 m2) within each major plot. A total of 46 species in the plantation, and 52 species in the natural forest, which belongs to 36 families were recorded. The diversity of species (H') is 2.19 in the plantation and 2.74 in the natural forest. The density of understory woody plant was 3842 stems/ha in the plantation and 4122 stems/ha in the natural forest. The densities of seedlings in the natural forest and the plantation were 8101 stems/ha and 4151 stems/ha, respectively. High similarity of woody species composition was found between the natural forest and the plantation. The E. grand& plantation was found favoring the regeneration and growth of Millitiaferruginia and Coffea arabica in a much better way than other underneath woody species. 展开更多
关键词 e. grandis natural forest natural regeneration PLANTATION woody species diversity
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Tree Planting:How Fast Can It Accelerate Post-fire Forest Restoration?——A Case Study in Northern Da Hinggan Mountains,China 被引量:1
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作者 LI Xiuzhen HE Hong S +3 位作者 WANG Xugao XIE Fuju HU Yuanman LI Yuehui 《Chinese Geographical Science》 SCIE CSCD 2010年第6期481-490,共10页
In 1987,a catastrophic fire burned over 1330000 ha in the densely forested area of the Da Hinggan Mountains in the northeastern China.After the fire,intensive management including burned trunk harvesting and coniferou... In 1987,a catastrophic fire burned over 1330000 ha in the densely forested area of the Da Hinggan Mountains in the northeastern China.After the fire,intensive management including burned trunk harvesting and coniferous tree planting had been conducted to accelerate forest restoration.To study the long term effect of these activities on forest recovery,we used a simulation modeling approach to study long-term(300 years) forest dynamics under current planting and natural regeneration scenarios.Results indicate that under tree planting scenario in the severely burned area,the dominant species Dahurian larch(Larix gmelinii) can reach pre-fire level(60% of the area) within 20 years and the maximum abundance can reach nearly 90% within 100 years.While under natural regeneration scenario,it needs about 250 years to reach its pre-fire level.From the perspective of timber production,tree planting can bring twice as much timber volume as that under natural regeneration within 300 years,which is the average longevity of L.gmelinii.It needs about 70 years to reach the timber volume of pre-fire level under the planting scenario,whereas it requires at least 250 years to reach the timber volume of pre-fire level under natural regeneration scenario.Another dominant species Asian White birch(Betula platyphylla) responded negatively to the planting of coniferous species.In general,tree planting of coniferous species after fire can greatly accelerate forest restoration in terms of species abundance and target timber volume,with desirable ecological and economic returns. 展开更多
关键词 tree planting natural regeneration post-fire forest restoration species abundance timber volume LANDIS model
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Integrating species and successional classes for wood production in a mixed forest restoration system in a neotropical region 被引量:1
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作者 Ananias Francisco Dias Junior Ana Lucia Martins Sodero Pincelli +4 位作者 Ana Paula Camara da Silva Alison Moreira da Silva Natalia Dias de Souza Mario Tommasiello Filho Jose Otavio Brito 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2313-2321,共9页
As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow tre... As forests in neotropical regions,particularly in developing countries,are devastated,interventions to restore biodiversity and its ecological functions are needed.Rural producers have thus been encouraged to grow trees for wood production as an economic activity.The objective of this study was to quantify the increment of wood density of four forest species from different successional classes of a mixed system of restoration in a neotropical forest in Brazil.Tree discs were sampled at breast height and analyzed radially by X-ray densitometry to obtain apparent density and basic density.Three trees each of a species from the pioneer,early and late secondary successional stages and of the dominant species in the climax community.The radial profiles indicated increasing density from the pith to bark of trunks,except for some variations due to wood defects and growth.Average density was 0.576 g cm^(-3),0.655 g cm^(-3),0.706 g cm^(-3)and 0.775 g cm^(-3),respectively,for Peltophorum dubium,Schinus terebinthifolius,Cariniana estrellensis and Hymenaea courbaril.Radial profiles indicated higher amplitudes in the apparent densities for slow-growing species.X-ray densitometry generated parameters such as minimum,average and maximum densities,and radial density variations.These parameters are important for understanding the ecological functional role of successional classes of the Atlantic Forest from the Neotropical region. 展开更多
关键词 X-ray densitometry timber species of neotropical forest Successional classes of forest species Maintenance of forest restoration
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A management planning system for even-aged and uneven-aged forests in northeast China 被引量:1
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作者 Xingji Jin Timo Pukkala Fengri Li 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期837-852,共16页
The most common scientific approach to numerical landscape-level forest management planning is combinatorial optimization aimed at finding the optimal combination of the treatment alternatives of stands. The selected ... The most common scientific approach to numerical landscape-level forest management planning is combinatorial optimization aimed at finding the optimal combination of the treatment alternatives of stands. The selected combination of treatments depends on the conditions of the forest, and the objectives of the forest landowners. A two-step procedure is commonly used to derive the plan. First, treatment alternatives are generated for the stands using an automated simulation tool. Second,the optimal combination of the simulated treatment schedules is found by using mathematical programming or various heuristics. Simulation of treatment schedules requires models for stand dynamics and volume for all important tree species and stand types present in the forest.A forest planning system was described for Northeast China. The necessary models for stand dynamics and tree volume were presented for the main tree species of the region. The developed models were integrated into the simulation tool of the planning system. The simulation and the optimization tools of the planning system were described. The optimization tool was used with heuristic methods, making it possible to easily solve also spatial forest planning problems, for instance aggregate cuttings.Finally, the use of the system is illustrated with a case study, in which nonspatial and spatial management plans are developed for the Mengjiagang Forest District. 展开更多
关键词 stand forests timber border alternatives aggregate landscape heuristic instance Northeast
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Optimum stand density of Chinese pine forests in Taihang limestone mountains, Shanxi Province
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作者 李永生 王棣 刘捷 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第2期92-94,共3页
Data analysis was made for 54 stands of Chinese pine forests for soil and water conservation and timber. The regression equations were drawn up on forest density and different rafter timber and bush coverage.Based on ... Data analysis was made for 54 stands of Chinese pine forests for soil and water conservation and timber. The regression equations were drawn up on forest density and different rafter timber and bush coverage.Based on those equations, the number of rafter timber trees, storage, number of non-raffer timber trees, stand volume and the output value were calculated for six different forest densities ranged from 1250 to 6600 trees/hm2.According to the economic and ecological criteria, the optimum density for Chinese pine forests was determined as 1 650 trees/hm2. 展开更多
关键词 Taihang MOUNTAINS LIMeSTONe MOUNTAINS CHINeSe PINe Water and soil CONSeRVATION timber forest forest density
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Positive association between forest management, environmental change, and forest bird abundance
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作者 Ernst Detlef Schulze Dylan Craven +8 位作者 Andrew M.Durso Jiri Reif Marcus Guderle Franz Kroiher Petra Hennig Anne Weiserbs Peter Schall Christian Ammer Nico Eisenhauer 《Forest Ecosystems》 SCIE CSCD 2019年第1期26-37,共12页
Background: The global decrease in wildlife populations, especially birds, is mainly due to land use change and increasing intensity of land use(Parmesan and Yohe 2003). However, impacts of management tools to mitigat... Background: The global decrease in wildlife populations, especially birds, is mainly due to land use change and increasing intensity of land use(Parmesan and Yohe 2003). However, impacts of management tools to mitigate biodiversity loss at regional and global scales are less apparent in forest regions that have a constant forest area,and which did not suffer from habitat degradation, and where forests are sustainably managed, such as in Central Europe or the northeastern USA. A biodiversity assessment for Germany suggested, for example, that bird populations were constant(Bundesamt für Naturschutz 2015).Results: This study shows that changes in the environment and in forest management over the past 45 years have had a significant, positive effect on the abundance of non-migratory forest bird species in Central Europe. Economy(timber prices and GDP), forest management(timber harvest and mixed forest area), and environmental factors(atmospheric CO_2 concentration and nitrogen deposition) were investigated together with changes in abundances of migratory and non-migratory forest birds using partial least squares path modeling. Climate change, resulting in longer seasons and milder winters, and forest management, promoting tree diversity, were significantly positively related to the abundance of non-migratory forest birds and explained 92% of the variation in their abundance in Europe. Regionally-migrating forest birds had stable populations with large variation, while birds migrating across continents declined in recent decades, suggesting significant, contrasting changes in bird populations in Europe. In northeastern North America we also found evidence that non-migratory forests have experienced long-term increases in abundance, and this increase was related to management. The increase of populations of nonmigratory forest birds in Europe and North America is associated with an increase in structural diversity and disturbances at the landscape level.Conclusions: Our results suggest that reports about bird decline in forests should separate between migratory and non-migratory bird species. Efforts to mitigate the general decline in bird abundance should focus on land-use systems other than forests and support sustainable forest management independent of economic conditions. 展开更多
关键词 CLIMATe change BIRDS BIODIVeRSITY timber HARVeST econo my forest management
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Tree species diversity and utilities in a contracting lowland hillside rainforest fragment in Central Vietnam
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作者 Yen Thi Van Roland Cochard 《Forest Ecosystems》 SCIE CSCD 2017年第3期182-200,共19页
Background: Within the highly bio-diverse ‘Northern Vietnam Lowland Rain Forests Ecoregion' only small, and mostly highly modified forestlands persist within vast exotic-species plantations. The aim of this study w... Background: Within the highly bio-diverse ‘Northern Vietnam Lowland Rain Forests Ecoregion' only small, and mostly highly modified forestlands persist within vast exotic-species plantations. The aim of this study was to elucidate vegetation patterns of a secondary hillside rainforest remnant(elevation 120–330 m, 76 ha) as an outcome of natural processes, and anthropogenic processes linked to changing forest values.Methods: In the rainforest remnant tree species and various bio-physical parameters(relating to soils and terrain)were surveyed on forty 20 m × 20 m sized plots. The forest's vegetation patterns and tree diversity were analysed using dendrograms, canonical correspondence analysis, and other statistical tools.Results: Forest tree species richness was high(172 in the survey, 94 per hectare), including many endemic species(〉16%; some recently described). Vegetation patterns and diversity were largely explained by topography, with colline/sub-montane species present mainly along hillside ridges, and lowland/humid-tropical species predominant on lower slopes. Scarcity of high-value timber species reflected past logging, whereas abundance of light-demanding species, and species valued for fruits, provided evidence of human-aided forest restoration and ‘enrichment' in terms of useful trees. Exhaustion of sought-after forest products, and decreasing appreciation of non-wood products concurred with further encroachment of exotic plantations in between 2010 and 2015. Regeneration of rare tree species was reduced probably due to forest isolation.Conclusions: Despite long-term anthropogenic influences, remnant forests in the lowlands of Vietnam can harbor high plant biodiversity, including many endangered species. Various successive future changes(vanishing species, generalist dominance, and associated forest structural-qualitative changes) are, however, expected to occur in smal forest fragments.Lowland forest biodiversity can only be maintained if forest fragments maintain a certain size and/or are connected via corridors to larger forest networks. Preservation of the forests may be fostered using new economic incentive schemes. 展开更多
关键词 Secondary evergreen monsoon forest Floristic patterns Tree species richness timber NTFP Biodiversity conservation
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Estimating costs of salvage logging for large-scale burned forest lands: A case study on Turkey's Mediterranean coast
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作者 Neşe Gülci 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第5期1899-1909,共11页
Different forest fires causing different degrees of effects occur in fire-sensitive forests due to various reasons such as climate change.Useful as well as harmful aspects of forest fires are a multi-disciplinary rese... Different forest fires causing different degrees of effects occur in fire-sensitive forests due to various reasons such as climate change.Useful as well as harmful aspects of forest fires are a multi-disciplinary research topic.Geographical information systems(GIS)and remote sensing(RS)methods offer a number of benefits for researchers and operators in the field of forest fire research.The present study analyses timber pricing based on forest contractor demands of post-salvage logging processes.The effect of timber obtained from compartment units on producers’pricing policy was modelled.Sapadere forest fire area(2500 ha)located in Antalya in Turkey was selected as the main study area.Topography parameters(aspect,slope and slope position),stand types(diameter class and crown closure),and burn severity were analyzed together using GIS and R software packages.A multi-linear regression model(R^(2)=0.752)demonstrated that factors that had the most impact on pricing were slope position,aspect,stand age,crown closure and burn severity.This model can be used to estimate salvage logging prices in Calabrian pine(Pinus brutia Ten.)stands with similar parameters.Forest administrators and contractors may readily address the unit price of timber by estimating approximate costs in a given forest area for which they are going to bid.This will help reduce operational planning times of harvesting procedures in burned stands. 展开更多
关键词 timber extraction forest fires Stumpage sale Cost estimation SUSTAINABILITY Crown fire
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Linear programming approach for optimal forest plantation
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作者 Zohreh Mohammadi Soleiman Mohammadi Limaei Taymour Rostami Shahraji 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第2期299-307,共9页
The aim of this research was to identify species suitable for plantation. We first identified species for potentially suitable for plantation based on ecological capabilities regarding soil properties. We determined t... The aim of this research was to identify species suitable for plantation. We first identified species for potentially suitable for plantation based on ecological capabilities regarding soil properties. We determined the area of plantation for different species based on ecological capabilities. Then, we collected relevant data such as growth patterns of different species, labor requirements for plantation and plantation cost. A linear programming model and two integer linear programming models were used for optimization. The appropriate species based on ecological capabilities were ash, elm, maple, oak and bald cypress. A linear programming model was used based on ecological capabilities classification to determine the land area of different species for plantation. Then, two integer linear programming models were employed to select the species for plantation. We set ecological properties unequal for all of the species in the first run of the integer programming model. Two groups were classified: group one included maple and ash; group two included bald cypress,oak and elm. The second integer programming model assumed equal ecological properties for all the species.Results of linear programming showed that maple and bald cypress were appropriate for plantation at the site and their plantation areas should be 151.3 and 355.3 ha, respectively. Results of the first integer linear programming model showed that maple and bald cypress would be economically profitable for plantation. The results of the second integer linear programming model showed that only bald cypress would be appropriate for plantation. 展开更多
关键词 plantation integer timber sequestration forests planted forestry Alnus economically eucalyptus
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