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Letter from Li Peng Chairman of the Standing Committee of the National People's Congress, To China Society for Human Rights Studies 被引量:1
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作者 Li Peng 《The Journal of Human Rights》 2002年第1期1-1,共1页
China Society for Human Rights Studies, I would like to extend my warm greetings to the launch of your Human Rights magazine. Enjoying human rights fully is a lofty goal long pursued after by human race. Over the year... China Society for Human Rights Studies, I would like to extend my warm greetings to the launch of your Human Rights magazine. Enjoying human rights fully is a lofty goal long pursued after by human race. Over the years when they carried out revolution, construction and reforms, the Chinese people have struggled indomitably and strived incessantly to achieve this goal. Progress made in this regard has caught worldwide attention. When struggling for, safeguarding, promoting and developing human rights, the Chinese people have always combined the universality prin- 展开更多
关键词 Letter from Li Peng Chairman of the standing Committee of the National People’s Congress To China Society for Human Rights Studies LI
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Soil properties and not plant factors affect both abundant and rare microbial taxa after thinning in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu
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作者 Wanxia Peng Tongqing Song +5 位作者 Hu Du Feng Wang Fuping Zeng Yang Wang Shulin Chen Yinzhu Chen 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期81-94,共14页
Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communiti... Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communities(i.e.,bacterial,fungal),were evaluated under various thinning treatments in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu using Mi Seq sequencing.Thinning did not significantly change either abundant or rare bacterial and fungal community composition,but affected their alpha diversity.The Shannon–Wiener indexes of rare fungal taxa under medium thinning were significantly lower than in the light thinning(P<0.05 level).Xanthobacteraceae dominated the abundant bacterial taxa,and Saitozyma and Mortierlla the abundant fungal taxa.The most common rare bacterial taxa varied;there was no prevalent rare fungal taxa under different thinnings.In addition,soil available nitrogen,total phosphorus,and p H had significant effects on rare bacterial taxa.Nutrients,especially available phosphorus,but not nitrogen,affected abundant and rare soil fungi.The results indicate that soil properties rather than plant factors affect abundant and rare microbial communities in soils of mixed stands.Thinning,through mediating soil properties,influences both abundant and rare bacterial and fungal communities in the mixed C.lanceolata and S.tzumu stand. 展开更多
关键词 Diversity Abundant taxa Rare taxa THINNING Mixed stand
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Impact of cattle density on the structure and natural regeneration of a turkey oak stand on an agrosilvopastoral farm in central Italy
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作者 Alessandra Pacini Francesco Pelleri +4 位作者 Francesco Marini Alberto Maltoni Barbara Mariotti Gianluigi Mazza Maria Chiara Manetti 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期168-182,共15页
On an agrosilvopastoral farm in central Italy where Maremmana cattle graze in Turkey oak forests,we evaluated the impact of different livestock densities on stand structure,tree diversity and natural regeneration in f... On an agrosilvopastoral farm in central Italy where Maremmana cattle graze in Turkey oak forests,we evaluated the impact of different livestock densities on stand structure,tree diversity and natural regeneration in four types of grazed areas based on the grazing regime adopted:calf-grazed,high-intensity-grazed,low-intensity-grazed,ungrazed control.For each area,we set up three permanent circular plots(radius of 15 m)to survey the structural and dasometric characteristics of the overstorey,understorey,and regeneration layer.The results showed that grazing negatively affected the complexity of the forest structure and its potential to regenerate and maintain a high level of biodiversity.The differences in stand structure observed between the grazing areas were closely related to livestock density.The most sensitive components of the system were the understorey and the regeneration layers.Contrarily,the current grazing management did not affect the dominant tree structure or its composition.Our findings identified medium-term monitoring and regeneration management as the two significant aspects to consider when assessing sustainable livestock.New forests can be established by excluding graz-ing for about 20–25 years. 展开更多
关键词 AGROFORESTRY stand structure Regeneration Tree biodiversity Grazing intensity
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Simulation of Haloxylon Ammodendron Stand Basic Diameter Structure Based on Fuzzy Distribution Function
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作者 Shaohua Wang Chuanqiang Liu Ting Yang 《Agricultural Sciences》 2024年第1期132-145,共14页
Based on the investigation data of 12 Haloxylon ammodendron plots in the south edge of Gurbantunggut Desert, Fuzzy distribution was introduced into the study of Haloxylon ammodendron base diameter structure fitting ac... Based on the investigation data of 12 Haloxylon ammodendron plots in the south edge of Gurbantunggut Desert, Fuzzy distribution was introduced into the study of Haloxylon ammodendron base diameter structure fitting according to the consistency between the characteristics of Fuzzy distribution function and the distribution series of cumulative percentage of stand base diameter, and the fitting precision and effect of Fuzzy distribution function were discussed. The root mean square error RMSE and determination coefficient R<sup>2</sup> values showed that Fuzzy-Γ<sub>1</sub>, Fuzzy-Γ<sub>2</sub>, Fuzzy-Γ<sub>3</sub>, Fuzzy-Γ<sub>4</sub> had good fitting performance, among which Fuzzy-Γ<sub>1</sub> had relatively high fitting precision, and its parameters were closely related to stand age and density, Fuzzy-Γ<sub>2</sub> distribution function was the second, and Fuzzy-Γ<sub>4</sub> distribution function had the worst fitting effect. By introducing a parameter c from the similarity of four distribution function formulas, a generalized Fuzzy distribution function Fuzzy-Γ<sub>5</sub> is obtained. This function shows the highest fitting accuracy. Most of the values of parameter c are near 1 or 2, which shows that the diameter distribution is mainly approximate to Fuzzy-Γ<sub>1</sub> and Fuzzy-Γ<sub>2</sub>. 展开更多
关键词 Fuzzy Distribution Function Haloxylon Ammodendron Base Diameter Distribution stand Factor
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Study on Free-Standing Riser Under Different Working Conditions Based on 3D Co-Rotational Beam Element
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作者 HUANG Chen GU Ji-jun +3 位作者 JIA Ji-chuan CHEN Lei-lei WANG Shu-jiang GAO Lei 《China Ocean Engineering》 SCIE EI CSCD 2024年第5期725-738,共14页
When the free standing riser(FSR)is in service in the ocean,its mechanical properties are affected by various factors,including complex ocean current forces,buoyancy of the buoyancy can,and torque caused by the deflec... When the free standing riser(FSR)is in service in the ocean,its mechanical properties are affected by various factors,including complex ocean current forces,buoyancy of the buoyancy can,and torque caused by the deflection of the upper floating body.These loads have a great influence on the deformation and internal force of the FSR.The static performance of FSR is investigated in this research under various working conditions.The finite element model of FSR is established based on the co-rotational method.The arc length approach is used to solve the model.The load is exerted in increments.The current load on the riser changes with the configuration of the riser.The accuracy of the numerical method is verified by Abaqus software.The calculation time is also compared.Then,the effects of uniform current,actual current and floating body yaw motion on FSR are studied by parameter analysis.Additionally,the influence of the FSR on the ocean current after the failure of part of the buoyancy can chamber is analyzed.The results show that the numerical model based on the co-rotational method can effectively simulate the large rotation and torsion behavior of FSR.This method has high computational efficiency and precision,and this method can quickly improve the efficiency of numerical calculation of static analysis of deep-water riser.The proposed technology may serve as an alternative to the existing proprietary commercial software,which uses a complex graphical user interface. 展开更多
关键词 free standing riser(FSR) co-rotational method finite element method ocean current nonlinear analysis TORSION
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The effects of data aggregation on long-term projections of forest stands development
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作者 Kobra Maleki Rasmus Astrup +2 位作者 Nicolas Cattaneo Wilson Lara Henao Clara Anton-Fernandez 《Forest Ecosystems》 SCIE CSCD 2024年第3期381-389,共9页
Forest management planning often relies on Airborne Laser Scanning(ALS)-based Forest Management Inventories(FMIs)for sustainable and efficient decision-making.Employing the area-based(ABA)approach,these inventories es... Forest management planning often relies on Airborne Laser Scanning(ALS)-based Forest Management Inventories(FMIs)for sustainable and efficient decision-making.Employing the area-based(ABA)approach,these inventories estimate forest characteristics for grid cell areas(pixels),which are then usually summarized at the stand level.Using the ALS-based high-resolution Norwegian Forest Resource Maps(16 m×16 m pixel resolution)alongside with stand-level growth and yield models,this study explores the impact of three levels of pixel aggregation(standlevel,stand-level with species strata,and pixel-level)on projected stand development.The results indicate significant differences in the projected outputs based on the aggregation level.Notably,the most substantial difference in estimated volume occurred between stand-level and pixel-level aggregation,ranging from-301 to+253 m^(3)·ha^(-1)for single stands.The differences were,on average,higher for broadleaves than for spruce and pine dominated stands,and for mixed stands and stands with higher variability than for pure and homogenous stands.In conclusion,this research underscores the critical role of input data resolution in forest planning and management,emphasizing the need for improved data collection practices to ensure sustainable forest management. 展开更多
关键词 Growth and yield models Dominant species Norway spruce Scots pine BROADLEAVES Forest resource map stand variability
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A People's Gala to Promote Mutual Under standing between China and Other Countries——2012 Understanding and Cooperation Dialogue held by CAFIU
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作者 Mu Jinling Zhao Tianming 《International Understanding》 2012年第2期34-38,32-33,共7页
正The Understanding and Cooperation Dialogue, Sponsored by the Chinese Association for International Understanding (CAFIU) and the China Foundation for Peace and Development (CFPD), and Co-organized by the Chinese Peo... 正The Understanding and Cooperation Dialogue, Sponsored by the Chinese Association for International Understanding (CAFIU) and the China Foundation for Peace and Development (CFPD), and Co-organized by the Chinese People' s Association for Peace and 展开更多
关键词 Understanding and Cooperation Dialogue held by CAFIU A People’s Gala to Promote Mutual Under standing between China and Other Countries
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Tibet: Nearer and Nearer——An Interview With Radi,chairman of the Standing Committee of the People's Congress of Tibet Autonomous Region
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《China Today》 2001年第5期8-10,共3页
关键词 In An Interview With Radi chairman of the standing Committee of the People’s Congress of Tibet Autonomous Region Nearer and Nearer TIBET
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Effects of Standing Time during Pretreatment on the Nitrite Concentration Detected by Spectrophotometric Method
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作者 Yingfei Zeng Juan Hu +2 位作者 Xianglong Bian Qianfeng Xia Tingwei Hu 《Journal of Materials Science and Chemical Engineering》 2024年第2期73-83,共11页
Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a... Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a great influence on the concentration of nitrite tested by spectrophotometric method. In this context, three kinds of food samples are prepared, including canned mustard, canned fish and home-made pickled water. A series of standing times are placed during the sample pretreatments and the corresponding nitrite contents in these samples are detected by spectrophotometric method based on N-ethylenediamine dihydrochloride. This study aims to find out a reasonable standing time during the pretreatment of food sample, providing influence factor for precise detection of nitrite. 展开更多
关键词 standing Time Spectrophotometric Method Nitrite Detection
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Existence and Stability of Standing Waves for the Nonlinear Schrödinger Equation with Combined Nonlinearities and a Partial Harmonic Potential
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作者 Wei Wang 《Journal of Applied Mathematics and Physics》 2024年第5期1606-1615,共10页
In this paper, we study the existence of standing waves for the nonlinear Schrödinger equation with combined power-type nonlinearities and a partial harmonic potential. In the L<sup>2</sup>-supercriti... In this paper, we study the existence of standing waves for the nonlinear Schrödinger equation with combined power-type nonlinearities and a partial harmonic potential. In the L<sup>2</sup>-supercritical case, we obtain the existence and stability of standing waves. Our results are complements to the results of Carles and Il’yasov’s artical, where orbital stability of standing waves have been studied for the 2D Schrödinger equation with combined nonlinearities and harmonic potential. 展开更多
关键词 Nonlinear Schrödinger Equation Orbital Stability standing Waves
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Tibet:14 Years of Brilliant, Extraor Achievements——An interview with Raidi, vice-chairman of the Standing Committee of the National People's Congress
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作者 OUR STAFF REPORTER 《The Journal of Human Rights》 2004年第2期2-10,共9页
Tremendous changes have takenplace in Tibet under the state policy of reform andopening up to the outside world, especially over thepast 14 years since the Fourth Plenary Session of the13th Central Committee of the Ch... Tremendous changes have takenplace in Tibet under the state policy of reform andopening up to the outside world, especially over thepast 14 years since the Fourth Plenary Session of the13th Central Committee of the Chinese CommunistParty. Unprecedented are the development of the localeconomy, and so are the changes in the outlook ofcities and countryside in the region, and life of ethnicTibetan has kept improving.Raidi, vice-chairman of the Standing Committee ofthe National People's Congress (NPC), is a mostqualified eyewitness to these changes. He was born intoa serf's family before the Democratic Reform in thelate 1950s, and had worked on various leading posts inTibet before he was elected to NPC, China's highestlegislature. In July 1990, Jiang Zemin, then generalsecretary of the CPC Central Committee, cited Raidi asan example when speaking on the question of humanrights during an inspection tour of Lhasa. Said he,'What do human rights mean? Comrade Raidi, aformer serf, now works as the second most seniormember of the Chinese Communist Party Committee ofTibet Autonomous Region, his experiences bring outthe meaning of human rights. Aren't we justified topublicize that?'Following is a slightly abridged text of an interviewgiven by Raidi to our staff reporter on the eve of theNew Year's day, in which he talked about theachievements Tibet has made over the past 14 yearsand the Party's policy in Tibet. 展开更多
关键词 Extraor Achievements Tibet vice-chairman of the standing Committee of the National People’s Congress An interview with Raidi
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Runoff Characteristics of Different Stands in Dongjiang Lake Reservoir Area
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作者 Zhangquan ZENG Yaqin XIAO +5 位作者 Dewei XIAO Qinxiang SHAN Ni ZHANG Yang SONG Canming ZHANG Rui YANG 《Meteorological and Environmental Research》 2024年第4期36-38,共3页
Different forest stands in the Dongjiang Lake Reservoir area of Zixing were selected as the research objects to study the characteristics of runoff generation in different forest stands.The results showed that there w... Different forest stands in the Dongjiang Lake Reservoir area of Zixing were selected as the research objects to study the characteristics of runoff generation in different forest stands.The results showed that there was no significant difference in annual runoff among M3,M1,and M5,and no significant difference between each forest stand and the control.The order was M3(22.75 mm)>M1(21.77 mm)>M5(20.14 mm).Forest vegetation generates less runoff through vegetation restoration compared to the control,indicating that forest vegetation reconstruction and restoration are beneficial for soil and water conservation. 展开更多
关键词 Dongjiang Lake Reservoir area stand Surface runoff Forest management
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Assessing cutter-rock interaction during TBM tunnelling in granite:Large-scale standing rotary cutting tests and 3D DEM simulations
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作者 Xin Huang Miaoyuan Tang +4 位作者 Shuaifeng Wang Yixin Zhai Qianwei Zhuang Chi Zhang Qinghua Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3595-3615,共21页
The widespread utilisation of tunnel boring machines(TBMs)in underground construction engineering requires a detailed investigation of the cutter-rock interaction.In this paper,we conduct a series of largescale standi... The widespread utilisation of tunnel boring machines(TBMs)in underground construction engineering requires a detailed investigation of the cutter-rock interaction.In this paper,we conduct a series of largescale standing rotary cutting tests on granite in conjunction with high-fidelity numerical simulations based on a particle-type discrete element method(DEM)to explore the effects of key cutting parameters on the TBM cutter performance and the distribution of cutter-rock contact stresses.The assessment results of cutter performance obtained from the cutting tests and numerical simulations reveal similar dependencies on the key cutting parameters.More specifically,the normal and rolling forces exhibit a positive correlation with penetration but are slightly influenced by the cutting radius.In contrast,the side force decreases as the cutting radius increases.Additionally,the side force shows a positive relationship with the penetration for smaller cutting radii but tends to become negative as the cutting radius increases.The cutter's relative effectiveness in rock breaking is significantly impacted by the penetration but shows little dependency on the cutting radius.Consequently,an optimal penetration is identified,leading to a low boreability index and specific energy.A combined Hertz-Weibull function is developed to fit the cutter-rock contact stress distribution obtained in DEM simulations,whereby an improved CSM(Colorado School of Mines)model is proposed by replacing the original monotonic cutting force distribution with this combined Hertz-Weibull model.The proposed model outperforms the original CSM model as demonstrated by a comparison of the estimated cutting forces with those from the tests/simulations.The findings from this work that advance our understanding of TBM cutter performance have important implications for improving the efficiency and reliability of TBM tunnelling in granite. 展开更多
关键词 Large-scale standing rotary cutting test Discrete element method(DEM)simulation Cutter-rock interaction Improved CSM(Colorado School of Mines) model Cutting force
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Fabrication of Free Standing Nanocellulose Film via Spray Coating and its Biomedical Application: A Review
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作者 Kirubanandan Shanmugam 《Journal of Clinical and Nursing Research》 2024年第4期411-447,共37页
Spraying nanocellulose onto films provides a quick and scalable way to create free-standing films with exceptional consistency and customizable thickness. This method increases the application of nanocellulose films i... Spraying nanocellulose onto films provides a quick and scalable way to create free-standing films with exceptional consistency and customizable thickness. This method increases the application of nanocellulose films in various industries and satisfies the requirements of large-scale production. In the field of biomedicine, spray-coated free-standing nanocellulose films hold great promise for applications such as drug delivery, tissue engineering, wound healing, device coatings, and biosensing. They are excellent nanomaterials for a variety of biomedical applications due to their special qualities, including biocompatibility, high mechanical strength, porous structure, large surface area, and adaptability. This paper reviewed the detailed exposure of the spray coating process of nanocellulose suspension onto free- standing films and its biomedical applications. 展开更多
关键词 SPRAYING Nanocellulose Film Free standing Film Thickness Basis weight
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Optimization models of stand structure and selective cutting cycle for large diameter trees of broadleaved forest in Changbai Mountain 被引量:6
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作者 郝清玉 周玉萍 +1 位作者 王立海 吴金卓 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期135-140,共6页
The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the d... The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the data from Hongshi Forestry Bureau, in Changbai Mountain region, Jilin Province, China. The data were measured in 232 permanent sample plots. With the data of permanent sample plots, the parameters of transition probability and ingrowth models were estimated, and some models were compared and partly modified. During the simulation of stand structure, four factors such as largest diameter residual tree (LDT), the ratio of the number of trees in a given diameter class to those in the next larger diameter class (q), residual basal area (RBA) and selective cutting cycle (C) were considered. The simulation results showed that the optimum stand structure parameters for large diameter trees are as follows: q is 1.2, LDT is 46cm, RBA is larger than 26 m^2 and selective cutting cycle time (C) is between 10 and 20 years. 展开更多
关键词 Large diameter tree stand structure OPTIMIZATION Broad-leaved forest MODEL
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Soil heterotrophic respiration in Casuarina equisetifolia plantation at different stand ages 被引量:2
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作者 肖胜生 叶功富 +2 位作者 张立华 金钊 刘丽香 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第4期301-306,I0004,共7页
The soil respiration rates (Rh) in 6-year-old (young), 17-year-old (middle-age), 31-year-old (mature) Casuarina equisetifolia coastal plantations were measured using an LICOR-8100 automated soil CO2 flux syste... The soil respiration rates (Rh) in 6-year-old (young), 17-year-old (middle-age), 31-year-old (mature) Casuarina equisetifolia coastal plantations were measured using an LICOR-8100 automated soil CO2 flux system from May 2006 to April 2007. Results show that Rh displayed an obvious seasonal pattern across the observed years. The maximum values of Rh occurred at June and July and the minimum at December and January. Soil temperature and soil moisture as well as their interaction had significant effects on the monthly dynamics of Rh. The analysis by one-way ANOVA showed that Rh had a significantly exponential relation (p〈0.05) to soil temperature at soil depth of 5 cm, and had a linear relation (p〈0.05) to soil water content of the upper 20 cm. The result estimated by the two-factor model shows that soil temperature at soil depth of 5 cm and soil moisture at soil depth of 20 cm could explain 68.9%-91.9% of seasonal variations in Rh. The or- der of Rh rates between different stand ages was middle-age plantation〉mature plantation〉young-age plantation. With the increase of growth age of plantation, the Q10 of Rh increased. The contribution of Rh to total soil surface CO2 flux was 71.89%, 71.02% and 73.53% for the young, middle-age and mature plantation, respectively. It was estimated that the annual CO2 fluxes from Rh were 29.07, 38.964 and 30.530 t.ha^-1.a^-1 for the young, middle-age and mature plantation, respectively. 展开更多
关键词 soil heterotrophic respiration coastal plantation stand age Casuarina equiset(folia
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Study on tracheid variation of Picea koraiensis (nakai) in natural stand and plantation 被引量:1
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作者 任旭琴 王秋玉 李凤娟 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期115-118,147,共4页
Tracheid characteristics ofPicea koraiensis from natural stand in Liangshui area and plantation in Mao'ershan area were studied. The results of variance analysis showed that the tracheid length, diameter, and thic... Tracheid characteristics ofPicea koraiensis from natural stand in Liangshui area and plantation in Mao'ershan area were studied. The results of variance analysis showed that the tracheid length, diameter, and thickness of tracheid wall were significant differences between the growth rings. All those characteristics tend to increase from heart-center to bark. In natural stand, it has positive correlation between the characteristics. In plantation, the tracheid length has positive correlation with the trachied diameter, while both the trachied length and the trachied diameter has negative correlation with the thickness of trachied wall. The tracheid length and diameter have no significant difference in growth between natural stand and plantations. The thickness of tracheid wall from the plantation is a little thicker than that from the natural stand before 15 years. 展开更多
关键词 Picea koraiensis nakai PLANTATION Natural stand Tracheid characteristic VARIATION
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Studies on stand dynamic growth model for larch in Jilin in China 被引量:1
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作者 翁国庆 陈雪峰 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期323-326,共4页
The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had h... The stand growth and yield dynamic models for Larch in Jilin Province were developed based on the forest growth theories with the forest continuous inventory data. The results indicated that the developed models had high precision, and they could be used for the updating data of inventory of planning and designing and optimal decision of forest management. 展开更多
关键词 stand Dynamics Growth Prediction Model
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The runoff characteristics and harmonic analysis of the soil moisture dynamics in Robinia pseudoacacia stand 被引量:1
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作者 高鹏 刘作新 陈伏生 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期295-298,共4页
Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the wes... Robinia pseudoacacia stands act as a typical ecological protection forest in hilly semi-arid area of China. Two fields of surface runoff were separately set up in R. pseudoacacia stand and its clearcut area in the western Liaoning Province (1850-12225 E, 4024-4234 N) for measuring the characteristics of runoff and sediment as well as soil moisture dynamics. Contractive analysis of the two land types showed that there existed a significant difference in volumes of runoff and sediment between the sites of R. pseudoacacia stand and its clearcut area. The runoff volume and sediment volume in clearcut area were much bigger than those in R. pseudoacacia stand, with an increase amount of 40%-177% for runoff and 180%-400% for sediment. Hydrograph of surface runoff of typical rainfall showed that the peak value of runoff in R. pseudoacacia stand was decreased by 1.0-2.5?0-3m3s-1 compared with that in its clearcut area, and the occurring time of peak value of runoff in R. pseudoacacia stand was 10-20 min later than that in its clearcut area. Harmonic analysis of soil moisture dynamics indicated that the soil moisture in R. pseudoacacia stand was 2.3 % higher than that in clearcut area, and the soil moisture both in R. pseudoacacia stand and its clearcut area could be divided into dry season and humid season and varied periodically with annual rainfall precipitation. It was concluded that R. pseudoacacia stand plays a very important role in storing water, increasing soil moisture, and reducing surface runoff and soil erosion. 展开更多
关键词 Hilly semi-arid area Robinia pseudoacacia stand Runoff generation characteristics Soil moisture dynamics Harmonic analysis
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The variation of nutrient concentration in the rhizosphere of larch and ash in mixed and monoculture stands 被引量:3
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作者 张彦东 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期269-272,336-337,共4页
Soil samples were taken from rhizosphere zone and off-rhizosphere zone of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) in mixed and monoculture stands, and the nutrient concentration of N, P, and ... Soil samples were taken from rhizosphere zone and off-rhizosphere zone of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) in mixed and monoculture stands, and the nutrient concentration of N, P, and K was analyzed to study the effect of nutrients variation on yield improvement in the mixed stand. The result showed that: 1) The stand level total soil N concentration and available N in the mixed stand was similar to that in the monoculture stand of ash, but higher than that in monoculture stand of larch. The total N and available N concentration in rhizosphere soil of ash in the mixed stand was similar to that in the monoculture stand of ash, but the available N concentration in rhizosphere of larch in mixed stand was much higher than in its monoculture. 2) The stand level total P, total K concentration in the mixed stand was similar to that in monocul-ture stands of both species, but available P and K was more concentrated in the mixed stand than in the monoculture stands of ash. The rhizosphere available P and K of ash in the mixed stand was 44.1% and 13.5% (for the 9-yr-old stands) and 79.6% and 25.6% (for the 21-yr-old stands) higher than that in its monoculture. The improvement of soil P and K availability in the mixed stand is concluded. 展开更多
关键词 ASH LARCH Mixed plantation stand RHIZOSPHERE Soil nutrition
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