检索结果-南通市图书馆

Plant size,environmental factors and functional traits jointly shape the stem radius growth rate in an evergreen coniferous species across ontogenetic stages

在线全文

学校读者我要写书评

暂无评论

Journal of Plant Ecology 2021年第2期14卷 257-269页

作者： zhili liu Kouki Hikosaka Fengri Li Liangjun Zhu Guangze Jin Center for Ecological Research Northeast Forestry UniversityHarbin 150040China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbin 150040China Graduate School of Life Sciences Tohoku UniversitySendaiMiyagi 980-8578Japan School of Forestry Northeast Forestry UniversityHarbin 150040China National Engineering Laboratory for Applied Technology of Forestry&Ecology in South China College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha 410004China

Aims Plant size,environmental conditions and functional traits are important for plant growth;however,it is less clear which combination of these factors is the most effective for predicting tree growth across ontogenetic *** We selected 65 individuals of an evergreen coniferous species,Pinus koraiensis,with diameters at breast height(DBH)from 0.3 to 100 cm in Northeast *** each individual,we measured the stem radius growth rate(SRGR,µm/year)for the current year,environmental factors(light,soil nutrient and soil water)and functional traits(leaf,branch and root traits).Important Findings SRGR increased with DBH when the DBH was lower than 58 cm,whereas it decreased with DBH when the DBH was larger than 58 *** equation modeling analysis suggested that,when the DBH was 0–15 cm,plant size had a direct negative influence on SRGR and an indirect positive influence on SRGR due to the light intensity above the *** size had direct positive and negative effects when the DBH was 16–58 cm and 59–100 cm,*** the DBH was larger than 15 cm,soil parameters were more important than light intensity for *** functional traits selected for use in the best model were changed from the specific leaf area and wood density to the root nitrogen concentration with increasing tree *** summary,plant size,environmental factors and functional traits jointly shaped tree growth,and their relative influence varied with size,suggesting that the resources limiting tree growth may change from light to soil nutrient with increasing tree size.

关键词： tree growth specific leaf area wood density root nitrogen concentration light intensity soil nutrient

Middle Triassic Stratigraphy and Sedimentary Paleogeography of South China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2000年第3期19卷 70-76页

作者： Tong Jinnan liu zhili Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China

The Middle Triassic was the great turning period of South China from marine sedimentary basins to continental deposits or erosion. This paper summarizes the distribution and variation of the stratigraphic sequences, lithofacies and biotas in various Middle Triassic depositional basins of South China. The close relationship between the biotic paleoecology and the lithofacies as well as the sedimentary facies, thus the paleogeography, is demonstrated. The process of the transition from the depositional paleogeography and its relation to the tectonic settings is concluded.

关键词： Middle Triassic sedimentary facies and paleogeography South China.

Stratigraphic Correlation of Middle TriassicSequences among Different Paleogeographic Sedimentary Facies in South China

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2000年第1期19卷 3-10页

作者： Tong Jinnan Xiao Shiyu liu zhili Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074

Affected by the Indosinian movement, the sediments in the main part of South China, Yangtze platform, started to transform from marine to continental during the Middle Triassic. In the meantime, a noticeable paleogeographic and sedimentary facies differentiation occurred in the marginal regions of the platforms and produced completely different lithologic and paleontologic sequences in various paleogeographic gradients and sedimentary facies areas, which brought about the difficulties for the stratigraphic correlation based on the traditional stratigraphies. This paper proposes to use some characteristic environmental events as the markers of the stratigraphic correlation across various paleogeographic sedimentary facies, considering that some distinctive regional environmental events should have affected at the same time on the entire basin or the connected sedimentary regions and produced some closely related sedimentary records in the stratigraphic sequences though the affected intensity and recorded pattern might be different among the regions. The change of violent relative sea level (generally water depth) and the alteration of tectonic activity summarized from the dynamic mechanism of sedimentation are the best markers of environmental events for stratigraphic correlation. Based on the analysis and recognition of some significant environmental events at the typical stratigraphic sequences from various paleogeographic sedimentary facies and combined with the consideration of the variations in expressed form and strength of the events among different paleogeographic gradients and sedimentary facies, the stratigraphic sequences from different sedimentary facies can be easily correlated directly. Furthermore, the evolutionary history of the whole sedimentary basin can be clearly established.

关键词： Middle Triassic stratigraphic correlation environmental event southern Guizhou South China.

Investigating on casting mold (or core) making with coated sand by the selected laser sintering

在线全文

学校读者我要写书评

暂无评论

China Foundry 2004年第2期1卷 122-126页

作者： Zitian FAN Naiyu HUANG Yan LI zhili liu State Key Laboratory of Plastic Simulation and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiP.R.China

Using a special coated sand as the material of the selected laser sintering (SLS), the authors test and investigate the strength change of the test samples in terms of different sintering parameters (scanning speed, laser power, sintering thickness, and so on). The characteristics of coated sand hardening by laser beam are analyzed. The sintered mold (or core) for given casting is poured with molten metal.

关键词： rapid prototyping selected laser sintering(SLS) laser scanning casting mold(core) technological parameters

Thermal Model for the Double-gasbag Stratospheric Airship Considering the Effect of the Diaphragm

在线全文

学校读者我要写书评

暂无评论

Thermal Model for the Double-gasbag Stratospheric Airship Co...

Pollutional Lakes Must Be Treated By a Comprehensive Way,Organisms Purification is a Fundamental Tactics

第37届中国控制会议

作者： Nie Hongpeng Lin Xianwu Huang Long liu zhili School of Aerospace Engineering Xiamen University

In order to analyze the thermal behavior of the stratospheric airship more accurately,a thermal model,which takes account the effect of the diaphragm on the thermal behavior of the double-gasbag stratospheric airship is *** calculation method of the internal radiative heat flux of the double-gasbag stratospheric airship is proposed based on the net heat *** the thermal model of the double-gasbag stratospheric airship is studied.A numerical simulation for the doublegasbag stratospheric airship at high-altitude station-keeping condition is *** results show that the diaphragm has a great influence on the thermal behavior of the stratospheric airship,which lays the foundation for further research on the thermal model of the stratospheric airship in multi-gasbag case.

关键词： Stratospheric Airship Double-gasbag Diaphragm Net Heat Method

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Pollutional Lakes Must Be Treated By a Comprehensive Way,Org...

光学仪器法测定叶面积指数季节变化的误差分析

2005中国国际水处理技术高级专家论坛

作者： liu zhili (School of Life Science Nanjing University Nanjing 210093)

＜正＞In this paper,the guiding principle of treatment for pollutional lakes is *** the moment,there are guiding ideological,technical and methodological confusions in the treatment of ***,the author maintains that the end of administration should be formation and resurrection of the good bioecological systems,and the improvement of lakes productivity.A comprehensive method should be adopted to treatment of eutropher-type *** the prerequisite to cut out polluting sources,building plant purification systems is a fundamental tactics.

关键词： treatment of pollutional lakes good ecological system method of biopurificaton lake productivity treatment of comprehensive ways

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

林业科学 2016年第9期52卷 11-21页

作者：刘志理金光泽东北林业大学生态研究中心哈尔滨150040

【目的】以黑龙江凉水国家级自然保护区人工林地为研究区,探讨影响间接法（光学仪器法）测定森林叶面积指数（LAI）季节变化精度的因素,为更准确地运用该方法测定LAI提供科学依据。【方法】以红松人工林和兴安落叶松人工林为研究对象,... 详细信息

【目的】以黑龙江凉水国家级自然保护区人工林地为研究区,探讨影响间接法（光学仪器法）测定森林叶面积指数（LAI）季节变化精度的因素,为更准确地运用该方法测定LAI提供科学依据。【方法】以红松人工林和兴安落叶松人工林为研究对象,利用直接法和半球摄影法（DHP）及LAI-2000植物冠层分析仪2种间接法测定其LAI季节变化（5—10月）,并研究光学仪器法测定LAI精度的误差源（木质部、冠层水平上的集聚效应、簇内集聚效应和自动曝光设置）产生偏差的季节性变异。【结果】对于红松人工林,DHP和LAI-2000在不同时期测定的LAI均低于直接法测定值,分别低估55%-68%和19%-35%;对于兴安落叶松人工林,DHP和LAI-2000在大部分时期低于直接法测定值,但在叶凋落后期均高于直接法测定值。不同误差源的校正参数及其对光学仪器法产生的偏差均存在明显的季节性差异。对于红松人工林,不同时期所有误差源产生的总偏差分别平均解释DHP,LAI-2000与直接法测定的LAI间差异的84%和79%。对于兴安落叶松人工林,利用Photoshop（PS）法校正木质部产生误差的情况下,不同时期所有误差源产生的总偏差对DHP、LAI-2000与直接法测定的LAI间差异的平均解释率分别为80%和65%,而利用背景值法校正木质部产生误差时,相应的平均解释率均低于5%。【结论】2种针叶林内,经过校正后DHP均比LAI-2000更适于测定LAI的季节变化;同时利用PS法校正2种光学仪器法在测定LAI季节变化时木质部产生误差的效果优于背景值法。

关键词：叶面积指数半球摄影法 LAI-2000植物冠层分析仪木质比例集聚效应自动曝光

在线全文

学校读者我要写书评

暂无评论

清朝的史注体式

图书与情报 2006年第6期 118-123页

作者：刘治立北京师范大学史学所北京100875

清朝是中国古代学术的总结时期,学者们以深厚的学力和高度的责任感,对以往的文化典籍进行全面的整理研究,采用各种形式注释历代史书,在史书注释方面取得了重大的成就,将古代史书注释工作推向顶峰。

关键词：清朝学者史书史注体式

在线全文

学校读者我要写书评

暂无评论

新奥运周期中国女子体操竞技实力研究

沈阳体育学院学报 2016年第1期35卷 109-115页

作者：刘智丽刘青成都体育学院四川成都610041

运用文献资料及录像观察等研究方法,通过对新奥运周期第44～46届世界体操锦标赛中国主力队员与世界优秀运动员各单项实力的对比研究,客观分析中国女子体操队在难度技术、稳定性及艺术表现力等方面的优势与不足。研究结果表明：我国女子... 详细信息

运用文献资料及录像观察等研究方法,通过对新奥运周期第44～46届世界体操锦标赛中国主力队员与世界优秀运动员各单项实力的对比研究,客观分析中国女子体操队在难度技术、稳定性及艺术表现力等方面的优势与不足。研究结果表明：我国女子体操高低杠和平衡木难度稍显优势,但完成质量与编排创新不足;跳马和自由体操难度发展严重滞后;成套动作稳定性不强,重大失误率较高;艺术美韵欠佳,个性风格不突出。针对存在问题为中国女子体操队备战里约奥运会提出了相关应对措施。

关键词：新奥运周期中国女子体操竞技实力