检索结果-南通市图书馆

Diversity and Chemical Composition of Weeds in sand-filled Mangrove Forest at Eagle Island, Niger Delta, Nigeria

American Journal of Plant Sciences 2020年第7期11卷 994-1007页

作者： Aroloye Ofo Numbere Department of Animal and Environmental Biology University of Port Harcourt Port Harcourt Nigeria

Mangroves are habitat specific and grow mainly in swampy soil, but due to anthropogenic activities (e.g. sand mining) other species had encroached into their habitat. It is thus hypothesized that change in species diversity will lead to change in soil chemistry. In a 40 m × 90 m plot, diversity index (H) and importance value (Iv) of weed were estimated. Soil and weed samples were collected and analyzed for total hydrocarbon content (THC), Zinc (Zn), Lead (Pb) and Cadmium (Cd). All samples were analyzed with atomic absorption spectrophotometric method using the HACH DR 890 calorimeter (wavelength 420 nm). The result shows that swampy soils were more acidic (3.1 - 3.5) than sandy soils (4.2 - 4.7). Swampy soil was also more saline and thus has higher conductivity (8320 - 9880 μS/cm) than sandy soil (4320 - 5650 μS/cm). Mangrove swamp had higher total organic carbon (TOC) (2.25% - 3.41%) than sandy soil (0.12% - 0.21%). There was a significant difference in THC and heavy metals in soil (F8,63 = 2.04, P 8,63 = 247.0, P > 0.05). Concentration of THC and heavy metal was higher in plant than in soil. Reissantia indica, an aquatic weed, had the highest concentration of THC in root soil. A total of fifteen (15) weed species were identified, out of which Mariscus

关键词： Heavy Metals Mangrove Weed Soil Species Diversity sand fill Swamp

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

Impact of Human Disturbance on Fiddler Crab (<i>Uca tangeri</i>) Burrow Morphology, Distribution and Chemistry at Eagle Island, Niger Delta, Nigeria

引用

Open Journal of Marine Science 2020年第4期10卷 191-202页

作者： Aroloye O. Numbere Department of Animal and Environmental Biology University of Port Harcourt Choba Nigeria

Fiddler crabs are described as ecosystem engineers because of their burrow constructing ability. It was hypothesized that human activity will impact crab burrows. The study area was delineated into lowly, medium and highly impacted plots. Crab holes were randomly counted and their width, length and surface area estimated. Burrow soils were collected and analyzed for Cadmium (Cd), Lead (Pb) and Zinc (Zn) using spectrophotometric method (HACH DR 890 colorimeter). The result indicates that burrow width was significantly different between impacted plots (P 0.05), but highly impacted plot has the longest length while lowly impacted plot has the shortest length. Again, the surface area of crab burrow varies significantly (P 2) followed by medium (390.30 ± 57.65 cm2) and high (265.16 ± 30.85 cm2) impacted plots. Similarly, lowly impacted area has more number of burrows (n = 55) followed by medium (n = 30) and highly (n = 23) impacted plots. Highly impacted plot had the highest Cd and Pb concentration whereas lowly impacted plot had the highest Zn concentration. This implies that burrow morphology and chemistry exemplify the level of anthropogenic impa

关键词： Burrow Human Disturbance Heavy Metals Mangroves Fiddler Crab sand fill

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

Computer simulation of metal forming processes

Computer simulation of metal forming processes

引用

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： K.N. Solomonov V.P. Abashkin Laboratory of Superplastic Materials Deformation Moscow State Steel and Alloys Institute 4 Leninsky Prospect 119991 Moscow Russia Laboratory of Superplastic Materials Deformation Moscow State Steel and Alloys Institute 4 Leninsky Prospect 119991 Moscow Russia

In the environment of visual programming DELPHI there is developed the program complex enabling to make express-analysis of the picture of metal flow while forming of work-pieces and to offer technological receptions for elimination of non-uniformity of shaping sepa-rate parts of workpiece, and also for decrease in the forces necessary for workpiece forming.

关键词： sand fill epure of boundary contact stresses slope line relative contour flow line boundary contact stresses contour of the workpiece the line of metal flow divide.

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

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

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

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：