检索结果-南通市图书馆

Community structure of Lumbricidae in beech woodland of the Bieszczady National Park, Southeast Poland

Pedosphere 2021年第3期31卷 391-397页

作者： Anna MAZUR-PĄCZKA Grzegorz PĄCZKA Joanna KOSTECKA Kevin R.BUTT Marcin JAROMIN Mariola GARCZYŃSKA agnieszka podolak University of Rzeszów Faculty of Biology and AgricultureDepartment of Natural Theories of Agriculture and Environmental Education1a Cwiklinskiej St.Rzeszów 35-959Poland University of Central Lancashire Forensic and Applied SciencesPreston PR12HEUK Rzeszów University of Technology Faculty of ChemistryDepartment of Biotechnology and Bioinformatics6 Powstancow Warszawy AvenueRzeszów 35-959Poland

As ecosystem engineers,earthworms play a key role in the soil ***,due to increasing anthropogenic pressure,soil organisms,including earthworms,are being threatened by habitat *** this study,we undertook a qualitative and quantitative investigation of earthworms of the family Lumbricidae in four types of Carpathian beech woodland(Fagetum carpaticum),characterized by their understory vegetation(I,*** drymejae;Ⅱ,***;Ⅲ,***;and IV,***),in the Bieszczady National Park(Eastern Carpathians,Southeast Poland).At each investigated site,soil monoliths(25 cm×25 cm×25 cm)were examined by hand *** were expelled from deep soil layers using a weak formalin solution(0.4%).Depending on the phytocoenosis,7 species of Lumbricidae were identified at each of the sites I,Ⅱ,andⅢand 10 at site *** IV(***)differed significantly(P<0.05)from the other three sites with respect to earthworm biomass(59.71±39.53 g m^(-2))and the Shannon-Wiener diversity index(0.52±0.12).Although present three decades ago,the deep-burrowing species Octodrilus transpadanus and the litter-dwelling species Dendrobaena octaedra were not found at site IV in the present *** suspect that these two species may have been displaced by the invasive Lumbricus terrestris,which was not found at the same site in the *** observations warrant further investigation to verify the predicted effects of an invasive earthworm,including the potential effects on soils and other fauna and flora,which have been documented in numerous countries.

关键词： beech forest earthworm invasive species Shannon-Wiener diversity index species diversity species dominance

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

Manipulating Chladni Patterns of Ferromagnetic Materials by an External Magnetic Field

引用

Sound & Vibration 2021年第3期55卷 235-240页

作者： Kenneth R.podolak Vihan A.W.Wickramasinghe Gareth A.Mansfield Alex M.Tuller State University of New York Plattsburgh12901USA

Ernst Chladni is called the father of acoustics for his work,which includes investigating patterns formed by vibrating *** these patterns helps research involving standing waves and other harmonic behaviors,including studies of single electron orbits in *** experiment vibrates circular plates which result in well-known *** to traditional experiments that used sand or salt,we use magnetic materials,namely iron filings and nickel *** then manipulate the patterns by applying a localized external magnetic field to one of the rings that moves a segment of the magnetic material in that ring to the next inner *** results show a significant decrease in magnetic field necessary to move the magnetic material at higher frequencies as well as a significant decrease in the magnetic field required to move the magnetic material as nickel powder is substituted for iron filings while keeping the mass constant.

关键词： Chladni ferromagnetism acoustics

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

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

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

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：