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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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Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations:a global data synthesis
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作者 Xiuqing Nie Hui Wang +1 位作者 Jian Wang Shirong Liu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期131-141,共11页
Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC c... Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC chemical compositions,we evaluated global patterns of concentra-tion,individual chemical composition(alkyl C,O-alkyl C,aromatic C,and carbonyl C),and their distribution even-ness.Our results indicate a notably higher SOC,a markedly larger proportion of recalcitrant alkyl C,and lower easily decomposed carbonyl C proportion in natural forests.How-ever,SOC chemical compositions were appreciably more evenly distributed in plantations.Based on the assumed con-ceptual index of SOC chemical composition evenness,we deduced that,compared to natural forests,plantations may have higher possible resistance to SOC decomposition under disturbances.In tropical regions,SOC levels,recalcitrant SOC chemical composition,and their distributed evenness were significantly higher in natural forests,indicating that SOC has higher chemical stability and possible resistance to decomposition.Climate factors had minor effects on alkyl C in forests globally,while they notably affected SOC chemi-cal composition in tropical forests.This could contribute to the differences in chemical compositions and their distrib-uted evenness between plantations and natural stands. 展开更多
关键词 Global data synthesis natural forest Plantations Soil organic carbon Soil organic carbon chemical composition
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The Contribution of Hemispherical Photographs to Understand Natural Forest Regeneration in the AKAK Forest Area
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作者 Agbor James Ayamba Nkwatoh Athanasius Fuashi Kamah Pascal Bumtu 《Open Journal of Forestry》 2024年第3期313-326,共14页
Examining the contribution of hemispherical photographs in the understanding of Natural forest regeneration is very important in estimating the future forest structure, composition and to enforce conservation regulati... Examining the contribution of hemispherical photographs in the understanding of Natural forest regeneration is very important in estimating the future forest structure, composition and to enforce conservation regulations. This study sets out to examine the interaction between stump sprouting, LAI, site and canopy openness for the entire AKAK forest area and for the logging compartments;2013, 2015 and 2017 respectively. 49 sprouted stump were identified randonly. 20 m × 20 m plots were demarcated along a canopy gaps for each sprouted stump, the plots were established in such a manner that the sprouted stumps will be in the middle. For each of the selected 49 sprouted stump, indirect measurements of canopy cover were performed in the 49 plots of 20 m × 20 m (0.04 ha), giving a total of 1.96 ha of land covered. Galaxy S3 smartphone with a built-in Infinix ZERO 4 fish-eye lens with 198˚ view angle equidistant projection was used to take photos. The fish-eye lens was mounted on the phone camera and photograph were taken at a fixed height of 1.3 m. Results revealed that, the combine Principal Component Factor Analysis (2013, 2015 and 2017) of the correlation matrix for Sprout, Years, LAI 4%, LAI 5%, Canopy and Site openness, shows that factor 1 explained 62.6% of total variance while factor 2 explained 17.9% together explain 80.05% Communalities. For the year 2013, 2015 and 2017 respectively shows that there is a very strong correlation (p p < 0.0005) between LAI4 and LAI5. 展开更多
关键词 Hemispherical Photographs natural forest Regeneration AKAK forest
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Natural forest ALS-TLS point cloud data registration without control points 被引量:1
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作者 Jianpeng Zhang Jinliang Wang +3 位作者 Feng Cheng Weifeng Ma Qianwei Liu Guangjie Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期809-820,共12页
Airborne laser scanning(ALS)and terrestrial laser scanning(TLS)has attracted attention due to their forest parameter investigation and research applications.ALS is limited to obtaining fi ne structure information belo... Airborne laser scanning(ALS)and terrestrial laser scanning(TLS)has attracted attention due to their forest parameter investigation and research applications.ALS is limited to obtaining fi ne structure information below the forest canopy due to the occlusion of trees in natural forests.In contrast,TLS is unable to gather fi ne structure information about the upper canopy.To address the problem of incomplete acquisition of natural forest point cloud data by ALS and TLS on a single platform,this study proposes data registration without control points.The ALS and TLS original data were cropped according to sample plot size,and the ALS point cloud data was converted into relative coordinates with the center of the cropped data as the origin.The same feature point pairs of the ALS and TLS point cloud data were then selected to register the point cloud data.The initial registered point cloud data was fi nely and optimally registered via the iterative closest point(ICP)algorithm.The results show that the proposed method achieved highprecision registration of ALS and TLS point cloud data from two natural forest plots of Pinus yunnanensis Franch.and Picea asperata Mast.which included diff erent species and environments.An average registration accuracy of 0.06 m and 0.09 m were obtained for P.yunnanensis and P.asperata,respectively. 展开更多
关键词 Airborne laser scanning(ALS) Terrestrial laser scanning(TLS) REGISTRATION natural forest Iterative closest point(ICP)algorithm
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Detecting the presence of natural forests using airborne laser scanning data
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作者 Marie-Claude Jutras-Perreault Terje Gobakken +1 位作者 Erik Næsset Hans OleØrka 《Forest Ecosystems》 SCIE CSCD 2023年第6期668-680,共13页
Centuries of forest exploitation have caused significant loss of natural forests in Europe,leading to a decline in populations for many species.To prevent further loss in biodiversity,the Norwegian government has set ... Centuries of forest exploitation have caused significant loss of natural forests in Europe,leading to a decline in populations for many species.To prevent further loss in biodiversity,the Norwegian government has set a target of protecting 10%of the forested area.However,recent data from the National Forest Inventory(NFI)reveals that less than 2%of Norway's forested area consists of natural forests.To identify forests with high conservation value,we used vertical and horizontal variables derived from airborne laser scanning(ALS)data,along with NFI plot measurements.Our study aimed to predict the presence of natural forests across three counties in southeastern Norway,using three different definitions:pristine,near-natural,and semi-natural forests.Natural forests are scarce,and their underrepresentation in field reference data can compromise the accuracy of the predictions.To address this,we assessed the potential gain of including additional field data specifically targeting natural forests to achieve a better balance in the dataset.Additionally,we examined the impact of stratifying the data by dominant tree species on the performance of the models.Our results revealed that semi-natural forests were the most accurately predicted,followed by near-natural and pristine forests,with Matthews correlation coefficient values of 0.32,0.24,and 0.17,respectively.Including additional field data did not improve the predictions.However,stratification by species improved the accuracy of predictions for near-natural and semi-natural forests,while reducing accuracy for pristine forests.The use of horizontal variables did not improve the predictions.Our study demonstrates the potential of ALS data in identifying forests with high conservation value.It provides a basis for further research on the use of ALS data for the detection and conservation of natural forests,offering valuable insights to guide future forest preservation efforts. 展开更多
关键词 natural forest ALS naturalNESS Vertical variables Horizontal variables BIODIVERSITY forest condition Ecosystem services
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A novel model to evaluate spatial structure in thinned conifer-broadleaved mixed natural forests
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作者 Hui Liu Xibin Dong +3 位作者 Yuan Meng Tong Gao Liangliang Mao Ran Gao 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1881-1898,共18页
In order to ensure the effective analysis and reconstruction of forests,it is key to ensure the quantitative description of their spatial structure.In this paper,a distance model for the optimal stand spatial structur... In order to ensure the effective analysis and reconstruction of forests,it is key to ensure the quantitative description of their spatial structure.In this paper,a distance model for the optimal stand spatial structure based on weighted Voronoi diagrams is proposed.In particular,we provide a novel methodological model for the comprehensive evaluation of the spatial structure of forest stands in natural mixed conifer-broadleaved forests and the formulation of management decision plans.The applicability of the rank evaluation and the optimal solution distance model are compared and assessed for different standard sample plots of natural mixed conifer-broadleaved forests.The effect of crown width on the spatial structure unit of the trees is observed to be higher than that of the diameter at breast height.Moreover,the influence of crown length is greater than that of tree height.There are nine possible spatial structure units determined by the weighted Voronoi diagram for the number of neighboring trees in the central tree,with an average intersection of neighboring crowns reaching 80%.The rank rating of natural forest sample plots is correlated with the optimal solution distance model,and their results are generally consistent for natural forests.However,the rank rating is not able to provide a quantitative assessment.The optimal solution distance model is observed to be more comprehensive than traditional methods for the evaluation of the spatial structure of forest stands.It can effectively reflect the trends in realistic stand spatial structure factors close to or far from the ideal structure point,and accurately assesses the forest spatial structure.The proposed optimal solution distance model improves the integrated evaluation of the spatial structure of forest stands and provides solid theoretical and technical support for sustainable forest management. 展开更多
关键词 Weighted Voronoi diagram Optimal distance model Spatial structure quantifi cation Thinning intensity Conifer-broadleaved mixed natural forests
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Effects of fire disturbance on the forest structure and succession in the natural broad-leaved/Korean pine forest 被引量:7
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作者 刘丽娟 葛建平 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期269-274,共6页
Investigations on charcoal in the soil, fire-scarred trees, stand composition, forest structure as well as regeneration status were carried out in the natural broad-leaved/Korean pine (Pinus koraiensis) forest after f... Investigations on charcoal in the soil, fire-scarred trees, stand composition, forest structure as well as regeneration status were carried out in the natural broad-leaved/Korean pine (Pinus koraiensis) forest after fire disturbance at Liangshui Nature Reserve on the mid-north of Xiaoxingan Mountains from 1990 to 1992, and the ecological effects of fire disturbance on the formation and succession of this kind of forest were analyzed according to the survey results. The average depth of charcoal in the soil was related to the timing of the fire. According to the characteristic of fire-scarred trees, the dynamic map of the fire behavior was drawn onto the topographic map. It showed that the dimension and extent of the fire disturbance was closely related with site conditions. Fire disturbance only led to a significant difference in stand composition and diameter class structure for the stands at different locations, rather than completely destroying the forest. After fire disturbance, the horizontal community structure was a mosaic of different patches, which were made up of different deciduous species or different sizes of Korean pines, and the succession trend of each patch was also different. In the sites with the heavy fire disturbance, the intolerant hardwood species were dominant, and there were a large number of regenerative Korean pine saplings under the canopy. In the moderate -disturbed sites, the tolerant hardwood species were dominant, and a small number of large size Korean pines still survived. In the light-disturbed sites, large size Korean pines were dominant. 展开更多
关键词 Pinus koraiensis natural forest Fire disturbance SUCCESSION
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Structure changes and succession dynamic of the natural secondary forest after severe fire interference 被引量:2
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作者 刘滨凡 刘广菊 王志成 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期123-130,I0002,共9页
The structure and dynamic succession law of natural secondary forest after severe fire interference in recent 20 years were studied by adopting the method of deducing time series from the spatial sequence of vegetatio... The structure and dynamic succession law of natural secondary forest after severe fire interference in recent 20 years were studied by adopting the method of deducing time series from the spatial sequence of vegetation in Heihe region, Heilongjiang, China. Two typical and widely distributed forest types in the study area, namely forest type A and forest type B, were selected as study subjects. Forest type A is pure broadleaf forest or broadleaf mixed forest mainly composing of superior Betula platyphylla and Populus davidiana in the area with gradient 〈25°, while forest type B is pure forest or mixed forest composing of superior Quercus mongolica and Betula davurica in the area with gradient 〉25°. Species richness, vegetation coverage, important value, and similarity index of commtmity in different layers (Herb, shrub, small tree, and arbor layers) were investigated and analyzed for the two typical forests. The results show that after fire interference, the species richness and coverage in each layer in forest type A were higher than that in forest type B. Both for forest type A and B, with elapse of post-fire years, the species richness and coverage of herbs and shrubs showed a decline tendency, while those of arbor layer present a rising tendency. Through comparison of the important values of species in each layer and analysis of community structure changes, the dynamic process of post-fire vegetation succession for forest type A and B was separately determined. Post-fire 80 years' succession tendency of forest type A is B. platyphylla and Larix gmelinii mixed forest. Its shrub layer is mainly composed of Corylus heterophylla and Vaccinium uliginosum, and herb layer is dominated by Carex tristachya, Athyrium multidentatum, and Pyrola incarnate; whereas, the post-fire 80 years' succession of forest type B is Q. mongolica and B. davurica mixed forest. Its shrub layer is mainly composed of lespedeza bicolar and corylus heterophylla and herb layer is dominated by Carex tristachya, Asparagus densiflorus, and Hemerocallis minor. 展开更多
关键词 natural secondary forest vegetation succession fire interference burned areas species richness important value similarity index succession law.
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Problems and relevant strategies on natural forest protection in Changbai Mountain forest area 被引量:1
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作者 王宪成 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期259-262,共4页
Changbai Mountain forest area is not only is a national timber base but also a green ecological defense for Songliao Plain of NE China. The Natural Forest Protection Project of this area has an important bearing on th... Changbai Mountain forest area is not only is a national timber base but also a green ecological defense for Songliao Plain of NE China. The Natural Forest Protection Project of this area has an important bearing on the social and economic sustainable development of Jilin Province or even the whole forest area in NE China. This paper summarized general conditions of natural forest in Changbai Mountain state-owned forest area and put forward six problems need to be urgently solved and five strategic suggestions on natural forest protection and sustainable management. 展开更多
关键词 Changbai Mountain natural forest protection COUNTERMEASURES
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Effects of Fertilization on Growth and Soil of Middle-aged Slash Pine Forest
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作者 肖兴翠 谢荣秀 +2 位作者 李志辉 康伟静 吴际友 《Agricultural Science & Technology》 CAS 2015年第11期2386-2393,共8页
In order to promote the growth of mid-aged Pinus elliottii plantation, the effects of different fertilizing amounts of formula fertilizer were studied on the growth, the soil and cost-benefit of 9 year-old Pinus el/io... In order to promote the growth of mid-aged Pinus elliottii plantation, the effects of different fertilizing amounts of formula fertilizer were studied on the growth, the soil and cost-benefit of 9 year-old Pinus el/iottii plantations in the north- ern part of Hunan, China. Three years after fertilization, the results showed that the increments of DBH, height, individual volume and stock volume of stand, and the fertilizer benefit of the different fertilization treatments were higher than the control to varying degrees, and among them, 700 g/tree was the best for promoting the growth of Pinus elliottii. Two years fertilization, the soil nutrients were improved compared with before, pH values of different layers decreased, organic matter and rapid available K contents increased, and rapid available N content increased dra- matically with the upper layer having an increase higher than the lower one; rapid available P decreased at different levels with the upper layer having a decrease lower than the lower one; and proper application of fertilizer could promote the growth of Pisolithus tinctofius, and 7 months after fertilization, the number of Pisolithus fruiting body generally increased with the increase of the fertilizer within 100-800 g/tree. The yield and benefit per unit area could be increased by fertiliza- tion for 1 time in middle-aged Pinus elliottii plantations, and the best fertilizing amount was N-P-K fertilizer 700 g/tree. 展开更多
关键词 FERTILIZATION Pinus elliottif middle-aged forest GROWTH SOIL
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Dynamic change of arborous species diversity in natural secondary forests after selective cutting on the north slope of Changbai Mountain, Northeast China
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作者 金永焕 周莉 +3 位作者 谷会岩 代力民 申光日 刘军 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期299-302,共4页
The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration perio... The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration period of 28 years were studied. The results showed that the arborous species richness (S) had little change and kept the range of 18-22 all along, the Simpson index (D) of the secondary layer and regeneration layer and whole stand had similar trends of change, but that of the canopy layer descended slowly in initial 15 years and had little change later, and the change of diversity index was not obvious and the Shannon-Wiener index (H? fluctuated in a very small scopes (H±10%). 展开更多
关键词 Arborous species diversity natural secondary forests Selective cutting Northeast China
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Spatial connectivity and distribution of landscape type in the natural secondary forests of eastern mountainous region,northeast China——a case study of Mao'ershan region in Heilongjiang Province
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作者 李淑娟 隋玉正 +2 位作者 冯海清 王凤友 李玉文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期141-144,i003,共5页
Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculate... Mao'ershan region is representative in the natural secondary forested region of the eastern mountainous region, northeast China. The landscape nearest neighbor index and landscape connectivity index were calculated with ARC/INFO software for Mao'ershan region. The spatial distribution of the landscape of the region was analyzed. The results showed that the landscape connectivity index of non-woodland was significantly higher than that of woodland. The landscape connectivity index of natural forest was nearly equal to zero, which means its fragmentation degree is high. The nearest neighbor index of plantation was lower than that of natural forest and non-forestland. Among the man-made forests, the distance index of the coniferous mixed plantation is the lowest, and its pattern is nearly glomeration. The landscape pattern of natural forest presented nearly random distribution. Among non-forest land, the distance index of cut blank was the lowest, and its pattern was also nearly glomeration. Keywords Landscape type - Landscape pattern - Nearest neighbor index - Landscape connectivity index - Natural secondary forest - Northeast China CLC number S759.92 Document code A Foundation item: This paper was supported by the Key Project of State Department of Science Technology (2002BA515B040).Biography: LI SHu-juan (1977), female. Lecture in Ocean University of China, Qingdao 266003, P. R. China.Responsible editor: Zhu Hong 展开更多
关键词 Landscape type Landscape pattern Nearest neighbor index Landscape connectivity index natural secondary forest Northeast China
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Study on Mosuo's Sacred Natural Sites of Mountainous Forest and Protection of Biological Diversity in Yongning-Lugu Lake Area
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作者 杨红 《Journal of Landscape Research》 2010年第7期18-22,共5页
With Mosuo's sacred natural sites of mountainous forest in Yongning-Lugu Lake area as the research subject,by using the method of ecology,the vegetation type in this area was initially identified.The control sampl... With Mosuo's sacred natural sites of mountainous forest in Yongning-Lugu Lake area as the research subject,by using the method of ecology,the vegetation type in this area was initially identified.The control sample plot of the same vegetation type at similar altitude and in similar soil condition would be selected and compared with the sample plot in sacred natural sites at length,so as to quantitatively analyze the protection of biological diversity in the perspective of ecological system.It showed that under the circumstance of the damage of ecological environment,complete natural vertical pattern was preserved thanks to sacred natural sites of mountainous forest established by reason of traditional religion and culture.The results of research and quantitative analysis showed that compared with the control sample plot of the same vegetation type,sacred natural sites were high in biological diversity and the species composition of plant community in sacred natural sites was closer to that of primitive forest.The result of quantitative analysis also indicated that sacred natural sites played a remarkable role in protecting vegetation and this protective function became more remarkable if the altitude was higher.And human were reminded to pay close attention to the preservation and protection function of sacred natural sites to natural ecological system at high altitude. 展开更多
关键词 MOSUO SACRED natural SITES of mountainous forest Protection of BIOLOGICAL DIVERSITY
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A statistical analysis of spatiotemporal variations and determinant factors of forest carbon storage under China's Natural Forest Protection Program 被引量:9
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作者 Shengnan Wu Jiaqi Li +5 位作者 Wangming Zhou Bernard Joseph Lewis Dapao Yu Li Zhou Linhai Jiang Limin Dai 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期410-419,共10页
The Natural Forest Protection Program(NFPP)is one of the key ecological forestry programs in China.It not only facilitates the improvement of forest ecological quality in NFPP areas,but also plays a significant role i... The Natural Forest Protection Program(NFPP)is one of the key ecological forestry programs in China.It not only facilitates the improvement of forest ecological quality in NFPP areas,but also plays a significant role in increasing the carbon storage of forest ecosystems.The program covers 17 provinces,autonomous regions,and municipalities with correspondingly diverse forest resources and environments,ecological features,engineering measures and forest management regimes,all of which affect regional carbon storage.In this study,volume of timber harvest,tending area,pest-infested forest,firedamaged forest,reforestation,and average annual precipitation,and temperature were evaluated as factors that influence carbon storage.We developed a vector autoregression model for these seven indicators and we studied the dominant factors of carbon storage in the areas covered by NFPP.Timber harvest was the dominant factorinfluencing carbon storage in the Yellow and Yangtze River basins.Reforestation contributed most to carbon storage in the state-owned forest region in Xinjiang.In state-owned forest regions of Heilongjiang and Jilin Provinces,the dominant factors were forest fires and forest cultivation,respectively.For the enhancement of carbon sequestration capacity,a longer rotation period and a smaller timber harvest are recommended for the Yellow and Yangtze River basins.Trees should be planted in stateowned forests in Xinjiang.Forest fires should be prevented in state-owned forests in Heilongjiang,and greater forest tending efforts should be made in the state-owned forests in Jilin. 展开更多
关键词 forest carbon storage Influencing factors natural forest protection program Variance decomposition Vector autoregression(VAR) model
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Soil Biological Changes for a Natural Forest and Two Plantations in Subtropical China 被引量:18
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作者 CHENGuang-Shui YANGYu-Sheng +2 位作者 XIEJin-Sheng LILing GAORen 《Pedosphere》 SCIE CAS CSCD 2004年第3期297-304,共8页
Conversion of natural forests into pure plantation forests is a common management practice in subtropical China.To evaluate the effects of forest conversion on soil fertility, microbe numbers and enzyme activities in ... Conversion of natural forests into pure plantation forests is a common management practice in subtropical China.To evaluate the effects of forest conversion on soil fertility, microbe numbers and enzyme activities in topsoils (0-10 cm)were quantified in two 33-year-old monoculture plantations of Castanopsis kawakamii Hayata (CK) and Cunninghamia lanceolata Lamb. (Chinese fir) (CF), and compared to a neighboring relict natural C. kawakamii forest (NF), in Sanming,Fujian. Five soil samples were collected once each in January, April, July, September and November in 2000 in each forest for laboratory analysis. Over the sampling year, there were significant differences for bacteria, fungi and actinomycetes between forests and between seasons (P < 0.05). The largest bacteria and fungi populations were in NF, while CF contained the greatest number of actinomycetes. There were also significant differences (P < 0.05) with microbial respiration for forests and seasons. Additionally, compared with NF, urease and acid phosphatase were significantly lower (P < 0.05)in CK and CF. Also, the correlations of soil hydrolysable N and available P to soil microbial and enzymatic activities were highly significant (P < 0.01). Thus, to alter the traditional Chinese fir monoculture so as to mimic the natural forest conditions, managing mixed stands of Chinese fir and broadleaf trees or conducting crop rotation of conifers and broadleaf trees as well as minimizing forest disturbances like clear-cutting, slash burning and soil preparing, could be utilized. 展开更多
关键词 chinese fir monoculture plantation natural forest soil enzymes soilmicrobes
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Carbon Return and Dynamics of Litterfall in Natural Forest and Monoculture Plantation of Castanopsis kawakamii in Subtropical China 被引量:8
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作者 GuoJianfen XieJinsheng +3 位作者 LuHaoliang LiuDongxia YangYusheng ChenGuangshui 《Forestry Studies in China》 CAS 2004年第1期33-36,共4页
The amount of carbon returned through litterfall and its seasonal pattern were studied in a natural forest of Castanopsis kawakamii (NF) and adjacent monoculture plantations of C. kawakamii (CK) and Chinese fir (Cunni... The amount of carbon returned through litterfall and its seasonal pattern were studied in a natural forest of Castanopsis kawakamii (NF) and adjacent monoculture plantations of C. kawakamii (CK) and Chinese fir (Cunninghamia lanceolata) (CF) in Sanming, Fujian Province, China. Mean annual carbon return through total litterfall over 3 years (from 1999 to 2001) was 5.097 t穐m2 in the NF, 4.337 t穐m2 in the CK and 2.502 t穐m2 in the CF respectively. Of the total carbon return in the three forests, leaf contribution accounted for 58.96%, 68.53% and 56.12% and twig 24.41%, 22.34% and 26.18%, respectively. The seasonal patterns of carbon return from total litterfall and leaf-litter were quite similar among the three forests. A peak of carbon input from litterfall in the NF and the CK occurred in spring except for the highest annual C return through branch litter of the NF in summer, while the CF showed the maximum C return in summer. The results of this study demonstrate that the natural forest has a greater C return through litterfall than monoculture plantations, which is beneficial to the increase of soil organic matter storage and the maintenance of soil fertility. 展开更多
关键词 carbon return LITTERFALL Castanopsis kawakamii Cunninghamia lanceolata natural forest monoculture plantation
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Microbial biomass in subtropical forest soils: effect of conversion of natural secondary broad-leaved forest to Cunninghamia lanceolata plantation 被引量:12
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作者 WANG Qing-kui WANG Si-long 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期197-200,共4页
Conversion of natural secondary broad-leaved forest to Cunninghamia lanceolata plantation is a common management practice in subtropical China. In this study, we compared soil physico-chemical properties, microbial bi... Conversion of natural secondary broad-leaved forest to Cunninghamia lanceolata plantation is a common management practice in subtropical China. In this study, we compared soil physico-chemical properties, microbial biomass in one natural secondary broad-leaved forest and two C. lanceolata plantation sites to estimate the effects of forest conversion on soil microbial biomass at the Huitong Experimental Station of Forestry Ecology, Chinese Academy of Sciences. Concentrations of soil organic carbon, total nitrogen, NH4^+-N and microbial biomass carbon and nitrogen were much lower under C. lanceolata plantations as compared to natural secondary broad-leaved forest. Soil microbial biomass C in the first and second rotation of C. lanceolata plantations was only 53%, 46% of that in natural secondary broad-leaved forest, and microbial biomass N was 97% and 79%, respectively. The contribution of microbial biomass C to soil organic C was also lower in the plantation sites. However, the contribution of microbial N to total nitrogen and NH4^+-N was greater in the C. lanceolata plantation sites. Therefore, conversion of natural secondary broad-leaved forest to C. lanceolata plantation and continuous planting of C. lanceolata led to the decline in soil microbial biomass and the degradation of forest soil in subtropical China. 展开更多
关键词 Soil microbial biomass Cunninghamia lanceolata plantation natural secondary broad-leaved forest forest conversion
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Ectomycorrhizal communities associated with Tilia amurensis trees in natural versus urban forests of Heilongjiang in northeast China 被引量:4
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作者 Lei Cui Li-qiang Mu 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第2期401-406,共6页
The deciduous linden tree (Tilia amurensis Rupr.) is protected at National Level II in China as a species of ecological and economic importance. The objective of this study was to assess and compare the ectomycorrhi... The deciduous linden tree (Tilia amurensis Rupr.) is protected at National Level II in China as a species of ecological and economic importance. The objective of this study was to assess and compare the ectomycorrhizal communities associated with T. amurensis in natural versus urban forests of central Heilongjiang Province. The percentage of T. amurensis colonisation by ectomycorrhiza was more than 60 % in urban forests, compared to 34-49 % in natural forests. Use of a combi- nation of morphological and molecular methods docu- mented 18 ECM (ectomycorrhizal) types among three sites; 12-13 ECM species were identified in the natural sites versus 9 species in the urban site. Four ECM species (Boletus sp., Tuber sp., Inocybe sp.2, Leccinum sp.1) were the dominant mycorrhizal symbionts, and Cenococcum geophilum and Russula sp. were found only in the natural forests. 展开更多
关键词 Tilia amurensis Rupr Ectomycorrhizalfungi natural forests Heilongjiang Province
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Comparison of foliar nutrient concentrations between natural and artificial forests of Pinus sylvestris var. mongolica on sandy land, China 被引量:7
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作者 ZHU Jiao-jun TAN Hui +1 位作者 KANG Hong-zhang XU Mei-ling 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期177-184,共8页
In order to examine the causes of degradation of Pinus sylvestris var. mongolica plantations on sandy land, the foliar concentrations of N, P, K and C were analyzed and compared between the field grown P. sylvestris v... In order to examine the causes of degradation of Pinus sylvestris var. mongolica plantations on sandy land, the foliar concentrations of N, P, K and C were analyzed and compared between the field grown P. sylvestris var. mongolica trees from two provenances (natural forests and plantations). The results indicated that natural tree needles had lower N, P and C concentrations, and higher K concentrations than those of plantation tree needles. For plantation tree needles, ratios of N: P, P. K and N: K increased with tree age before 45 years old; but they were not clear for the natural tree needles. Compared with the conclusions reported on Pinus spp., we found that the foliar N and P concentrations were in the optimal range for both natural and plantation tree needles. This result suggested that N or P might not be the absolute limit factors in plant nutrient for P sylvestris var. mongolica on sandy land. However, foliar K concentrations in both natural and plantation tree needles were much lower than those reported on Pinus spp. (〉4.80 g kg-1).The N: P ratio of natural needles was in the adequate ranges, but N: P ratio of plantation needles was out of the adequate ranges. These results indicated that there was a better balanced nutrition status in the natural forest than in the plantations. If only considering the foliar nutrient concentrations of P sylvestris var. mongolica from different provenances, it might be concluded that the degradation phenomenon of P. sylvestris var. mongolica plantations was not induced by nutrition deficiency of absolute nutrients of N and P, but might be induced by other mineral nutrients or by the effectiveness of N and P nutrients. The unbalanced nutrition status and relatively quick decomposition of needles in the plantations might also contribute to the degradation. 展开更多
关键词 Degradation phenomenon forest ecosystem on sandy land N: P ratio natural Mongolian pine Pinus sylvestris var. mongolica Plantation Mongolian pine
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Natural regeneration characteristics of Pinus sylvestris var. mongolica forests on sandy land in Honghuaerji, China 被引量:20
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作者 ZHU Jiao-jun KANG Hong-zhang +2 位作者 TAN Hui XU Mei-ling WANG Jun 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期253-259,共7页
Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values o... Natural regeneration in Mongolian pine, Pinus sylvesttis var. mongolica, forest at Honghuaerji of China (the original of the natural Mongolian pine, forest on sandy land) was studied in 2004. The total mean values of regeneration indexes were higher in mature stands (more than 80% individual stems were older than 50 years), the maximum of regeneration index reached 29 seedlings, m^ 2, with lowest values in the younger stand, e.g., in 32-year old and 43-year old stands. The stand age was an important factor determining the natural regeneration, which was the best in the older stands in this investigation (e.g. about 80-year old). The regeneration index seemed not to be closely in relation to canopy openness although Mongolian pine is a photophilic tree species. In each type of gaps, natural regeneration was very well. Regeneration indexes were satisfactory at the south and east edges in the circle gaps; and at the east edge of the narrow-square gaps. Results indicated that Mongolian pine, seedlings could endure shading understory, but it would not enter the canopy layer without gap or large disturbance, e.g., fire, wind/snow damage or clear cutting etc. These results may provide potentially references to the management and afforestation of Mongolian pine, plantations on sandy land in arid and semi-arid areas. Researches such as the comprehensive comparisons on regeneration, structure and ecological conditions and so on between natural Mongolian pine, forests and plantations should be conducted in the future. 展开更多
关键词 Pinus sylvestris var. mongolica Mongolian pine Sandy land natural regeneration Canopy openness forest gap Regeneration index
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