检索结果-南通市图书馆

Variations in the Volatile Organic Compound Emission Potential of Plant Functional Groups in the Temperate Grassland Vegetation of Inner Mongolia, China

引用

Journal of Integrative Plant Biology 2005年第1期47卷 13-19页

作者： Nian-PengHE xing-guohan Qing-MinPAN LaboratoryofQuantitativeVegetationEcology InstituteofBotanytheChineseAcademyofSciencesBeijing100093China

Abstract: The biogenic volatile organic compounds (VOC) emitted by the vegetation of a terrestrial ecosystem play a key role in both regional air quality and tropospheric chemistry. To describe the general emission properties of VOC of different plant functional groups (PFG) in a typical temperate grassland in Inner Mongolia, China, we randomly selected 175 plant species and measured the quantities of isoprene and monoterpene in situ. Results showed that most plants had low VOC emission potential at the species level, especially for some dominant plants, such as Leymus chinensis Tzvel., Stipa grandis Smirn., and Agropyron cristatum Gaertn. At the PFG level, the lowest VOC emission potential was found for perennial rhizome grasses, a major PFG in a typical temperate grassland ecosystem. The effects of overgrazing and subsequent vegetation succession on the emission of VOC by different plant life form functional groups (PLFG) were also discussed.

关键词： biogenic emission ecological group grassland vegetation isoprene monoterpene plant functional groups (PFG) volatile organic compounds (VOC)

来源：

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

Effect of Nitrogen Supply on the Nitrogen Use Efficiency of an Annual Herb, Helianthus annuus L.

引用

Journal of Integrative Plant Biology 2005年第5期47卷 539-548页

作者： Zhi-YouYUAN Ling-HaoLI Jian-HuiHUANG xing-guohan Shi-QiangWAN LaboratoryofQuantitativeVegetationEcology InstituteofBotanytheChineseAcademyofSciencesBeijing100093China LaboratoryofQuantitativeVegetationEcology InstituteofBotanytheChineseAcademyofSciencesBeijing100093China／／EnvironmentalSciencesDivisionOakRidgeNationalLaboratoryOakRidgeTN37831-6422USA

Abstract: Nitrogen use efficiency (NUE) is the product of nitrogen productivity (NP) and the mean residence time of nitrogen (MRT). Theory suggests that there should be a trade-off between both components, but direct experimental evidence is still scarce. To test this hypothesis, we analyzed the effect of varying nitrogen supply levels on NUE and its two components (NP, MRT) in Helianthus annuus L., an annual herb. The plants investigated were subjected to six nitrogen levels (0, 2, 4, 8, 16, and 32 g N/m2). Total plant production increased substantially with increasing nitrogen supply. Nitrogen uptake and loss also increased with nitrogen supply. Nitrogen influx (rin) and outflux (rout) were defined as the rates of nitrogen uptake and loss per unit aboveground nitrogen, respectively. Both rm and rout increased with increasing nitrogen supply. In addition, rm was far higher than rout. Consequently, the relative rate of nitrogen increment (rin-rout) also increased with nitrogen supply. There were marked differences between treatments with respect to parameters related to the stress resistance syndrome: nitrogen pool size, leaf nitrogen concentration, and net aboveground productivity increased with nitrogen supply. Plants at high nitrogen levels showed a higher NP (the growth rate per unit aboveground nitrogen) and a shorter MRT (the inverse of rout), whereas plants at low nitrogen levels displayed the reverse pattern. Shorter MRT for plants at high nitrogen levels was caused by the abscission of leaves that contained relatively large fractions of total plant nitrogen. We found a negative relationship between NP and MRT, the components of NUE, along the gradient of nitrogen availability, suggesting that there was a trade-off between NP and MRT. The NUE increased with increasing nitrogen availability, up to a certain level, and then decreased. These results offer support for the hypothesis that adaptation to infertile habitats involves a low nitrogen loss (long MRT in

关键词： meanresidence time nitrogen productivity nitrogen supply nitrogen use efficiency plant strategies

来源：

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

Editorial： New Opportunities and a New Beginning

引用

Journal of Integrative Plant Biology 2005年第1期47卷 1-1页

作者： HongMA xing-guohan Editors-in-chief

As we begin 2005, plant biologists have great opportunities to unlock the secrets of plant life. The realization of the importance of biodiversity and global ecology has promoted increasing efforts in understanding individual, population, and community plant biology. At the same time, the advances in plant molecular biology, genetics,

关键词：

来源：

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

DRAGON-Lab―Next generation internet technology experiment platform

引用

Science in China(Series F) 2008年第11期51卷 1908-1918页

作者： WANG JiLong LI ZhongHui LV guohan JIANG CaiPing LI xing ZHANG QianLi National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China Network Research-Center Tsinghua University Beijing 100084 China

Testbed technology is very important in the development of the Internet. Similar to the present internet, next generation internet also starts from testbed. There are two kinds of testbeds, testbed networks like CNGI-CERNET2, Internet2, Geant; testbed systems like PlanetLab, NS2. DRAGON-Lab can be viewed as both testbed network and testbed system. DRAGON-Lab is an independent AS （autonomous system） and connected to multiple real networks. On the other hand, DRAGON-Lab integrates many resources of its own, partners＇ and internet＇s, so as to provide open service. DRAGON-Lab has a large scale, provides open service, supports remote visualized experiments and programmable experiments. More details will be introduced in this paper.

关键词： Internet testbed system confederation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

某市国民消防安全素质结构及其影响因素分析

引用

消防技术与产品信息 2018年第9期31卷 32-36页

作者：邢鲁宁刘国翰杭州市消防支队浙江杭州310002 浙江理工大学法政学院浙江杭州310018

以2016年第一季度杭州市国民消防安全素质和消防满意度调查数据为基础,通过因子分析方法和结构方程(SEM)分析方法,发现"消防安全知识获取"、"消防安全应对能力"属于表层因素,而"消防安全责任感"和"消防安全防范意识"属于深层因素,传统... 详细信息

以2016年第一季度杭州市国民消防安全素质和消防满意度调查数据为基础,通过因子分析方法和结构方程(SEM)分析方法,发现"消防安全知识获取"、"消防安全应对能力"属于表层因素,而"消防安全责任感"和"消防安全防范意识"属于深层因素,传统的消防宣传和消防训练主要对表层因素产生作用,而提高居民对消防部门的工作满意度则对深层因素能够产生明显的促进作用。

关键词：消防安全国民消防安全素质因子分析结构影响因素

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：