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A study on state-owned forest area stakeholders' behavior
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作者 ZHANG Ai-mei CHEN Shao-zhi +2 位作者 WU Wei-hong LI Wen-yu WANG Yang-yang 《Ecological Economy》 2014年第2期164-171,共8页
The development of state-owned forest area plays a very important role in the development of Chinese forest industry, and even in the construction of national economy. As the backbone of Chinese forestry development, ... The development of state-owned forest area plays a very important role in the development of Chinese forest industry, and even in the construction of national economy. As the backbone of Chinese forestry development, it contributes to Chinese economic development, ecological environment protection and social progress. How to balance all stakeholders' interest and behaviors remains as one of the focuses in the study of sustainable development of forest areas. On this basis, researches were carried out and described in the paper. Firstly, the paper goes through the concept and scope of state-owned forest area in China; Secondly, it defines the stakeholders of state-owned forest area, and discusses over the problems in stakeholders' behaviors from the aspect of responsibility, rights and interests; and Finally, it designs the stakeholders' behaviors on the basis of existing problems and provides constructive suggestions on deeper reform of state-owned forest areas. 展开更多
关键词 stakeholders' behaviors state-owned forest area China
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Discussion on the relationship between Construction of Forest Towns and Reform & Development of State-owned Forest Farms
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作者 Sha Qiao 《Frontiers Research of Architecture and Engineering》 2018年第4期113-116,共4页
In recent years, China's social economy has continued to develop. While paying attention to the pursuit of the economy, people are paying more and more attention to the pursuit of quality of life. China has vast t... In recent years, China's social economy has continued to develop. While paying attention to the pursuit of the economy, people are paying more and more attention to the pursuit of quality of life. China has vast territory and abundant resources, forest resources are particularly rich, in order to make full use of forest resources and regulate the use and protection of forests, China has promoted the development of forestry by deepening the construction and reform of state-owned forest farms, and using forest resources to obtain benefits to meet people's living needs. This paper explores the necessity and advantages of building a forest town by analyzing the reform and development situation of state-owned forest farms. 展开更多
关键词 forest TOWNS state-owned forest farms REFORM and DEVELOPMENT
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State-Owned Capital Participation in Private Enterprises:A Perspective of Debt Financing
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作者 He Dexu Zeng Min Zhang Shuonan 《China Economist》 2024年第1期14-42,共29页
This study takes debt financing as the entry point and explores the impact of state-owned capital participation in private enterprises from the perspectives of“unarticulated rules”and“articulated rules”.The study ... This study takes debt financing as the entry point and explores the impact of state-owned capital participation in private enterprises from the perspectives of“unarticulated rules”and“articulated rules”.The study finds that state-owned capital participation significantly reduces the debt financing costs of private enterprises and expands the scale of their debt financing.This conclusion remains valid after a series of endogeneity and robustness tests.Further analysis of the mechanism reveals that state-owned capital participation improves the debt financing of private enterprises through multiple channels:Enhancing their social reputation,mitigating the“statistical bias”they face,optimizing their information quality,and reducing the“shareholder-creditor”agency problems.This paper conceptualizes these benefits as the“complementary advantages of heterogeneous shareholders”.This not only constructs a theoretical framework for“reverse mixed-ownership reform”but also better narrates the Chinese story of“mixed-ownership reform”by adopting a more universally applicable theory of equity structure.Additionally,the paper supplements existing research on the macro-and meso-level relationship between the government and the market by exploring the government’s positive role at the micro-level. 展开更多
关键词 Mixed-ownership reform reverse mixed-ownership reform state-owned capital debt financing heterogeneous shareholders
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Research on Mixed Ownership Reform of State-Owned Enterprises from the Perspective of Marxist Political Economy
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作者 Honghong Lu 《Proceedings of Business and Economic Studies》 2024年第5期61-67,共7页
Under China’s socialist system,state-owned enterprises are key forces driving the economic trajectory and providing strong momentum.These enterprises not only bear the crucial responsibility of advancing the process ... Under China’s socialist system,state-owned enterprises are key forces driving the economic trajectory and providing strong momentum.These enterprises not only bear the crucial responsibility of advancing the process of national modernization but also serve as the core of the national economic lifeline through their irreplaceable status and function amidst changing times.In the new era,with the advent of the technological revolution and the wave of globalization,state-owned enterprises face unprecedented opportunities and challenges.As a significant aspect of state-owned enterprise reform,the mixed ownership reform is not only a transformation in the structure of enterprise ownership but also a reflection of China’s broader,comprehensive reform efforts.By deeply advancing this reform,it will help optimize the allocation of state-owned assets and significantly boost technological and management innovation within state-owned enterprises,ensuring their competitiveness in the intense market environment.Therefore,this paper will conduct an in-depth analysis of the mixed ownership reform of state-owned enterprises from the perspective of Marxist political economy. 展开更多
关键词 Marxist political economy state-owned enterprise reform Mixed ownership
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Internal Control Management and Risk Prevention Measures of State-Owned Enterprises
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作者 Bing Liu 《Journal of Electronic Research and Application》 2024年第3期1-6,共6页
As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an... As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an important part of enterprise management,internal control management plays an irreplaceable role.Especially in the current domestic and international economic situation is complex and changeable,market competition is increasingly fierce environment,to strengthen the internal control management of state-owned enterprises and risk prevention measures is particularly important.This paper starts with the importance of internal control management and risk prevention for state-owned enterprises,and analyzes the problems and strategies in the internal control management and risk prevention of state-owned enterprises,in order to build a more comprehensive and efficient risk management system for state-owned enterprises to adapt to the ever-changing market environment and realize sustainable development. 展开更多
关键词 state-owned enterprises Internal control management Risk prevention
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基于Deep Forest算法的对虾急性肝胰腺坏死病(AHPND)预警数学模型构建
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作者 王印庚 于永翔 +5 位作者 蔡欣欣 张正 王春元 廖梅杰 朱洪洋 李昊 《渔业科学进展》 CSCD 北大核心 2024年第3期171-181,共11页
为预报池塘养殖凡纳对虾(Penaeus vannamei)急性肝胰腺坏死病(AHPND)的发生,自2020年开始,笔者对凡纳对虾养殖区开展了连续监测工作,包括与疾病发生相关的环境理化因子、微生物因子、虾体自身健康状况等18个候选预警因子指标,通过数据... 为预报池塘养殖凡纳对虾(Penaeus vannamei)急性肝胰腺坏死病(AHPND)的发生,自2020年开始,笔者对凡纳对虾养殖区开展了连续监测工作,包括与疾病发生相关的环境理化因子、微生物因子、虾体自身健康状况等18个候选预警因子指标,通过数据标准化处理后分析病原、宿主与环境之间的相关性,对候选预警因子进行筛选,基于Python语言编程结合Deep Forest、Light GBM、XGBoost算法进行数据建模和预测性能评判,仿真环境为Python2.7,以预警因子指标作为输入样本(即警兆),以对虾是否发病指标作为输出结果(即警情),根据输入样本和输出结果各自建立输入数据矩阵和目标数据矩阵,利用原始数据矩阵对输入样本进行初始化,结合函数方程进行拟合,拟合的源代码能利用已知环境、病原及对虾免疫指标数据对目标警情进行预测。最终建立了基于Deep Forest算法的虾体(肝胰腺内)细菌总数、虾体弧菌(Vibrio)占比、水体细菌总数和盐度的4维向量预警预报模型,准确率达89.00%。本研究将人工智能算法应用到对虾AHPND发生的预测预报,相关研究结果为对虾AHPND疾病预警预报建立了预警数学模型,并为对虾健康养殖和疾病防控提供了技术支撑和有力保障。 展开更多
关键词 对虾 急性肝胰腺坏死病 预警数学模型 Deep forest算法 PYTHON语言
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Revelation from Management System Reform of State-owned Forests of Hessen State in Germany
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作者 LIU Yong LI Zhiyong YE Bing Research Institute of Forestry Policy and Information, Chinese Academy of Forestry, Beijing 100091, P. R. China 《Chinese Forestry Science and Technology》 2008年第1期31-35,共5页
The paper analyzes the management system reforms of state-owned forest in Hessen State of Germany based on the forestry situation, and draws conclusions which can be used for reference in management system reform of s... The paper analyzes the management system reforms of state-owned forest in Hessen State of Germany based on the forestry situation, and draws conclusions which can be used for reference in management system reform of state-owned forest in China. The results are as follows: stepwise reform is the mode, ecology-centeredness is the principle, transparent property right is the precondition, detached function of government and forest industry groups is the key, and integrated law and regulation system is the guarantee. 展开更多
关键词 state-owned forest management system REFORM Hessen state GERMANY
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Implication of community-level ecophysiological parameterization to modelling ecosystem productivity:a case study across nine contrasting forest sites in eastern China 被引量:1
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作者 Minzhe Fang Changjin Cheng +2 位作者 Nianpeng He Guoxin Si Osbert Jianxin Sun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期1-11,共11页
Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations... Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model parameterization.Here we compared five methods for defining community-level specific leaf area(SLA)and leaf C:N across nine contrasting forest sites along the North-South Transect of Eastern China,including biomass-weighted average for the entire plant community(AP_BW)and four simplified selective sampling(biomass-weighted average over five dominant tree species[5DT_BW],basal area weighted average over five dominant tree species[5DT_AW],biomass-weighted average over all tree species[AT_BW]and basal area weighted average over all tree species[AT_AW]).We found that the default values for SLA and leaf C:N embedded in the Biome-BGC v4.2 were higher than the five computational methods produced across the nine sites,with deviations ranging from 28.0 to 73.3%.In addition,there were only slight deviations(<10%)between the whole plant community sampling(AP_BW)predicted NPP and the four simplified selective sampling methods,and no significant difference between the predictions of AT_BW and AP_BW except the Shennongjia site.The findings in this study highlights the critical importance of computational strategies for community-level parameterization in ecosystem process modelling,and will support the choice of parameterization methods. 展开更多
关键词 BIOME-BGC Community traits forest Ecosystems Model parameterization
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Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau 被引量:1
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作者 Teng Li Jianfeng Peng +3 位作者 Tsun Fung Au Jingru Li Jinbao Li Yue Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期72-82,共11页
Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-e... Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although S.saltuaria was more sensitive than A.faxoniana.The strong-est correlation was between S.saltuaria chronology and regional mean temperatures from June to November.Based on this relationship,a regional mean temperature from June to November for the period 1605-2016 was constructed.Reconstruction explained 37.3%of the temperature variance during th period 1961-2016.Six major warm periods and five major cold periods were identified.Spectral analysis detected significant interannual and multi-decadal cycles.Reconstruction also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau. 展开更多
关键词 Tree-ring analysis Mixed forests DENDROCLIMATOLOGY Qionglai Mountains
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Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020 被引量:1
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作者 Shi-Guang Wei Lin Li +3 位作者 Kun-Dong Bai Zhi-Feng Wen Jing-Gang Zhou Qin Lin 《Plant Diversity》 SCIE CAS CSCD 2024年第1期70-77,共8页
Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest chang... Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure. 展开更多
关键词 Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest
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一种基于KMeans与Random Forest的异常温升捕捉方法
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作者 汪海良 《现代建筑电气》 2024年第6期21-26,49,共7页
针对线路老化、线路过载的火灾频发问题,分析了线路老化、线路过载与异常温升之间的关联性,以电流值、线缆温度作为输入,利用KMeans聚类算法划分可能存在异常温升的区间,通过Random Forest算法识别线路过载问题,可以提前通知用户整改线... 针对线路老化、线路过载的火灾频发问题,分析了线路老化、线路过载与异常温升之间的关联性,以电流值、线缆温度作为输入,利用KMeans聚类算法划分可能存在异常温升的区间,通过Random Forest算法识别线路过载问题,可以提前通知用户整改线路,预防火灾的发生。 展开更多
关键词 线路过载 异常温升 Random forest KMeans
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Twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition
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作者 álvaro Rubio-Cuadrado Iciar Alberdi +8 位作者 Isabel Canellas Fernando Montes Jesús Rodríguez-Calcerrada Rosana López Guillermo G.Gordaliza María Valbuena-Carabana Nikos Nanos Ramón Perea Luis Gil 《Forest Ecosystems》 SCIE CSCD 2024年第3期358-370,共13页
There is an increasing interest in restoring degraded forests,which occupy half of the forest areas.Among the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free e... There is an increasing interest in restoring degraded forests,which occupy half of the forest areas.Among the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining attention.Natural dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these species.Here,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the 1960s.The most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought tolerance.These species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for Q.pyrenaica.In order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and 2015.Our results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade tolerance.After the abandonment of grazing and cutting,Q.pyrenaica expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly F.sylvatica,despite its lower drought and late-frost tolerance.If the current dynamics continue,F.sylvatica will overtake the rest of the species,which will be relegated to sites with shallow soils and steep slopes.Simultaneously,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear. 展开更多
关键词 forest succession Secondary forest WOODLAND Mixed forest COMPETITION RECRUITMENT
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Evolutionary fingerprint, phylogenetic and forest structure of tropical montane Atlantic cloud forests along an elevation gradient
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作者 Ravi Fernandes MARIANO Vanessa Leite REZENDE +7 位作者 Cléber Rodrigo de SOUZA Patrícia Vieira POMPEU Rubens Manoel dos SANTOS Carolina Njaime MENDES Aloysio Souza de MOURA Felipe Santana MACHADO Warley Augusto Caldas CARVALHO Marco Aurélio Leite FONTES 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1259-1271,共13页
Environmental conditions can change markedly over geographical distances along elevation gradients,making them natural laboratories to study the processes that structure communities.This work aimed to assess the influ... Environmental conditions can change markedly over geographical distances along elevation gradients,making them natural laboratories to study the processes that structure communities.This work aimed to assess the influences of elevation on Tropical Montane Cloud Forest plant communities in the Brazilian Atlantic Forest,a historically neglected ecoregion.We evaluated the phylogenetic structure,forest structure(tree basal area and tree density)and species richness along an elevation gradient,as well as the evolutionary fingerprints of elevation-success on phylogenetic lineages from the tree communities.To do so,we assessed nine communities along an elevation gradient from 1210 to 2310 m a.s.l.without large elevation gaps.The relationships between elevation and phylogenetic structure,forest structure and species richness were investigated through Linear Models.The occurrence of evolutionary fingerprint on phylogenetic lineages was investigated by quantifying the extent of phylogenetic signal of elevation-success using a genus-level molecular phylogeny.Our results showed decreased species richness at higher elevations and independence between forest structure,phylogenetic structure and elevation.We also verified that there is a phylogenetic signal associated with elevation-success by lineages.We concluded that the elevation is associated with species richness and the occurrence of phylogenetic lineages in the tree communities evaluated in Mantiqueira Range.On the other hand,elevation is not associated with forest structure or phylogenetic structure.Furthermore,closely related taxa tend to have their higher ecological success in similar elevations.Finally,we highlight the fragility of the tropical montane cloud forests in the Mantiqueira Range in face of environmental changes(i.e.global warming)due to the occurrence of exclusive phylogenetic lineages evolutionarily adapted to environmental conditions(i.e.minimum temperature)associated with each elevation range. 展开更多
关键词 Atlantic forest Cloud forest CONSERVATION Community ecology Montane forests Phylogenetic diversity Phylogenetic signal
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Assessment of large-scale multiple forest disturbance susceptibilities with AutoML framework: an Izmir Regional Forest Directorate case
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作者 Remzi Eker Kamber Can Alkiş Abdurrahim Aydın 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期73-88,共16页
Disturbances such as forest fires,intense winds,and insect damage exert strong impacts on forest ecosystems by shaping their structure and growth dynamics,with contributions from climate change.Consequently,there is a... Disturbances such as forest fires,intense winds,and insect damage exert strong impacts on forest ecosystems by shaping their structure and growth dynamics,with contributions from climate change.Consequently,there is a need for reliable and operational methods to monitor and map these disturbances for the development of suitable management strategies.While susceptibility assessment using machine learning methods has increased,most studies have focused on a single disturbance.Moreover,there has been limited exploration of the use of“Automated Machine Learning(AutoML)”in the literature.In this study,susceptibility assessment for multiple forest disturbances(fires,insect damage,and wind damage)was conducted using the PyCaret AutoML framework in the Izmir Regional Forest Directorate(RFD)in Turkey.The AutoML framework compared 14 machine learning algorithms and ranked the best models based on AUC(area under the curve)values.The extra tree classifier(ET)algorithm was selected for modeling the susceptibility of each disturbance due to its good performance(AUC values>0.98).The study evaluated susceptibilities for both individual and multiple disturbances,creating a total of four susceptibility maps using fifteen driving factors in the assessment.According to the results,82.5%of forested areas in the Izmir RFD are susceptible to multiple disturbances at high and very high levels.Additionally,a potential forest disturbances map was created,revealing that 15.6%of forested areas in the Izmir RFD may experience no damage from the disturbances considered,while 54.2%could face damage from all three disturbances.The SHAP(Shapley Additive exPlanations)methodology was applied to evaluate the importance of features on prediction and the nonlinear relationship between explanatory features and susceptibility to disturbance. 展开更多
关键词 AutoML forest disturbances forest fire INSECT SUSCEPTIBILITY WIND
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Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation
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作者 Wen-Hao Zeng Shi-Dan Zhu +3 位作者 Ying-Hua Luo Wei Shi Yong-Qiang Wang Kun-Fang Cao 《Plant Diversity》 SCIE CAS CSCD 2024年第4期530-536,共7页
Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change mitigation.Although forest attributes and environmental factors have been shown to impact aboveground biom... Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change mitigation.Although forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been investigated.In this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,China.Our results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other regions.Furthermore,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species evenness.When we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast height.These findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in China.Notably,many natural forests in southern China are not fully stocked.Therefore,their continued growth will increase their carbon storage over time. 展开更多
关键词 Subtropical forest Marginal tropical forest Aboveground biomass Species diversity forest structural attribute Environment factor
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Stand dynamics of old-growth hemlock forests in central Bhutan are shaped by natural disturbances
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作者 Karma Tenzin Craig R.Nitschke +3 位作者 Kathryn J.Allen Raphael Trouve Thiet V.Nguyen Patrick J.Baker 《Forest Ecosystems》 SCIE CSCD 2024年第4期434-447,共14页
Understanding how past disturbances have influenced the development of forests is critical for deciphering their current structure and composition and forecasting future changes.In this study,dendrochronological metho... Understanding how past disturbances have influenced the development of forests is critical for deciphering their current structure and composition and forecasting future changes.In this study,dendrochronological methods were applied to uncover the disturbance history of old-growth hemlock-dominated forests in central Bhutan.Analysis of tree-ring samples from two old-growth hemlock stands,located in two different topographic settings,identified the importance of gap-phase dynamics in facilitating recruitment and growth releases and producing complex,multi-aged structure s over time.One site showed evidence of a near stand-replacing disturbance in the late 1700s,while the other showed no evide nce of high-severity disturbance at any time over the last 400 years.At both sites low-to medium-severity disturbances,some of which appear to be associated with cyclones originating in the Bay of Bengal,dominated the disturbance regime.The hemlock stands exhibited a significant positive association between cyclone occurrence and growth release events and between recruitment pulses and growth release events.From 1800 to 1970 there was an increase in recruitment of angiosperm tree species at most sites and a corresponding decline in conifer recruitment.Over the past 50 years there has been little new recruitment;this may be due to light limitation in the understory from shade-tolerant angiosperms and bamboo in the lower strata of these stands.Significant variations in disturbance dynamics and recruitment were observed across the study sites,suggesting that other factors,such as topography and climate,may be influencing long-term stand development patterns.This study highlights the complex interplay between historical disturbance regimes and tree recruitment in shaping the age and size structures of old-growth hemlock forests in central Bhutan.It also provides new insights into the dynamics of these forests that can be used to support effective forest conservation and management in the future. 展开更多
关键词 forest structure Hemlock forest HIMALAYA Natural disturbance
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Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests
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作者 Frederico Tupinambá-Simões Adrián Pascual +3 位作者 Juan Guerra-Hernández Cristóbal Ordóñez Tiago de Conto Felipe Bravo 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期14-25,共12页
The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high resolution.To confirm the con-sistency in the retrieval of forest structural par... The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high resolution.To confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is crucial.We analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus pyrenaica.The area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning paths.Ground reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in phenology.Ninety-six percent of all pairs matched below 65 cm.For DBH,phenology barely altered estimates.We observed a strong agreement when comparing HLS-based tree height distributions.The values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous species.Tree volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions. 展开更多
关键词 Precision forestry forest monitoring Mobile laser scanning forest inventory
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PLFA Analysis of Soil Microbial Community Structure in Different Forest Types
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作者 Jiayi Zhang Songzhe Li +2 位作者 Xiangping Fu Shunbao Lu Yanjie Zhang 《American Journal of Plant Sciences》 CAS 2024年第10期930-939,共10页
Soil soluble organic matter is an important component in the study of carbon and nitrogen cycling in terrestrial ecosystems. Soil microorganisms, as soil decomposers, participate in soil biogeochemical processes and p... Soil soluble organic matter is an important component in the study of carbon and nitrogen cycling in terrestrial ecosystems. Soil microorganisms, as soil decomposers, participate in soil biogeochemical processes and play an important role in maintaining the balance of soil ecosystems. As a typical subtropical regional unit, Queensland, Australia, is a relatively concentrated distribution area of forests in Australia. It is very sensitive to climate change and plays an important role in Australian climate and even global climate change. Its unique natural environment and ecosystem occupy a special position in the world. However, the knowledge of available carbon and nitrogen pool and microbial activity in forest soil is still very limited. Pinus elliottii, Araucaria cunninghamii and Agathis australis are the three most important forest types in southern Queensland, Australia. In our research, the function and structural diversity of soil microbial communities of these three forest types were studied using biochemical and molecular biological methods, and the effective carbon and nitrogen pools of soil of different forest types and related microbial processes were discussed, which has important theoretical guiding significance for further research on the structure and function of soil ecosystem. The number of PLFAs in the soil of P. elliottii was 45, the number of PLFAs in the soil of Araucaria cunninghamii and Agathis australis was 39 and 35, respectively. The number and content of PLFAs monomer in P. elliottii were higher than those in the other two kinds of forest soil. 展开更多
关键词 forest Type SOIL Microbial Community PLFA
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Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement
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作者 Yuanyuan Wang Xinzhu Dai +5 位作者 Xingling Chen Dan Zhang Guiqing Lin Yuanhang Zhou Tianyi Wang Yulong Cui 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期146-162,共17页
Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban... Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future. 展开更多
关键词 Species diversity forest characteristics Biomass carbon sink forest-type effect Urbanization effect Urban forests
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Sustaining forest biodiversity:Exploring the effect of long-term natural disturbance dynamics on contemporary lichen communities in primary forest ecosystems
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作者 Rhiannon Gloor Marek Svitok +11 位作者 Martin Mikolas Jenyk Hofmeister Josef Halda Pavel Janda Francesco Maria Sabatini Lucie Zemanova Arne Buechling Daniel Kozak Matej Ferencik Michal Frankovic Martin Dusatko Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期556-567,共12页
In this era of biodiversity loss and climate change,quantifying the impacts of natural disturbance on forest communities is imperative to improve biodiversity conservation efforts.Epiphytic and epixylic lichens are ef... In this era of biodiversity loss and climate change,quantifying the impacts of natural disturbance on forest communities is imperative to improve biodiversity conservation efforts.Epiphytic and epixylic lichens are effective forest quality bioindicators,as they are generally long-lived organisms supported by continuity of specific forest structures and their associated microclimatic features.However,how lichen communities respond to the effects of fluctuating historical disturbances remains unclear.Using a dendrochronological approach,this study investigates how natural disturbance dynamics indirectly influence various lichen community metrics in some of Europe's best-preserved primary mixed-beech forests.Mixed modelling revealed that natural historical disturbance processes have decades-long effects on forest structural attributes,which had both congruent and divergent impacts on lichen community richness and composition.Total species richness indirectly benefited from both historical and recent higher-severity disturbances via increased standing dead tree basal area and canopy openness respectively-likely through the presence of both pioneer and late-successional species associated with these conditions.Red-listed species richness showed a dependence on habitat continuity(old trees),and increased with disturbance-related structures(standing dead trees)whilst simultaneously benefiting from periods without severe disturbance events(old trees and reduced deadwood volume).However,if the disturbance occurred over a century in the past,no substantial effect on forest structure was detected.Therefore,while disturbance-mediated forest structures can promote overall richness,threatened species appear vulnerable to more severe disturbance events-a concern,as disturbances are predicted to intensify with climate change.Additionally,the high number of threatened species found reinforce the critical role of primary forest structural attributes for biodiversity maintenance.Hence,we recommend a landscape-scale conservation approach encompassing forest patches in different successional stages to support diverse lichen communities,and the consideration of long-term disturbance dynamics in forest conservation efforts,as they provide critical insights for safeguarding biodiversity in our changing world. 展开更多
关键词 Mixed-beech forests Species richness Old-growth forests Carpathian mountains Biodiversity conservation DENDROECOLOGY Fagus sylvatica
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