The Vertical Distribution and Diurnal Migration of the Crustacea Amphipoda Collected During the SOND Cruise, 1965 I. The Gammaridea

1976 ◽  
Vol 56 (2) ◽  
pp. 359-382 ◽  
Author(s):  
Michae L H. Thurston
Keyword(s):  
Cluster Analysis ◽  
Factor Analysis ◽  
Vertical Distribution ◽  
Canary Islands ◽  
Sampling Methods ◽  
Methods And Techniques ◽  
Biological Sampling ◽  
And Cluster Analysis ◽  
And Migration ◽  
The Vertical Distribution

INTRODUCTIONDetailed studies of the vertical distribution and migration of the micronekton, plankton and sonic scattering layers in an oceanic environment off Fuertaventura in the Canary Islands were made from R.R.S. ‘Discovery’ during September to December 1965. A general account, including a statement of the objectives of the cruise, has been given by Currie, Boden & Kampa (1969). Foxton (1969) has described the biological sampling methods and techniques utilized. Results of sonic scattering investigations have been published by Blaxter & Currie (1967) and Boden & Kampa (1967). The present study deals only with the pelagic amphipods, and forms a contribution to a series (Angel, 1969; Clarke, 1969b; Baker, 1970; Foxton, 1970a, b; Badcock, 1970; Roe, 1972a, b, c, d; Pugh, 1974) dealing with the distribution and migration of the major taxa sampled during the investigation. An objective summary of the plankton data utilizing factor analysis and cluster analysis has been provided by Angel & Fasham (1973, 1974).

The Vertical Distribution and Diurnal Migration of the Crustacea Amphipoda Collected during the SOND Cruise, 1965 II. The Hyperiidea and General Discussion

1976 ◽  
Vol 56 (2) ◽  
pp. 383-470 ◽  
Author(s):  
Michael H. Thurston
Keyword(s):  
Vertical Distribution ◽  
Canary Islands ◽  
Sampling Techniques ◽  
And Migration ◽  
Ring Net ◽  
The Vertical Distribution ◽  
Diurnal Migration

INTRODUCTIONThis paper forms the second and last part of a study of the vertical distribution and migration of pelagic Amphipoda based on material collected off Fuertaventura, Canary Islands, during the SOND Cruise in 1965. The first part (Thurston, 1976b) dealt with the Gammaridea. The data presented herein deal with the Hyperiidea, to which is added a general discussion.The background to the cruise has been given by Currie, Boden & Kampa (1969), and Foxton (1969) has described the gear and methods used. This analysis is based primarily on samples obtained from a series of 1 m2 ring-net (N 113) hauls, but has been supplemented by selected materials from modified 3 m Isaacs-Kidd Mid-water Trawl (IKMT), neuston net and 1 m2 Rectangular Mid-water Trawl (RMT 1) hauls. Thurston (1976b) has discussed the limitations of the sampling techniques as they affect the present results.

A Modified Freeze-Core Technique to Quantify the Depth Distribution of Fauna in Stony Streambeds

1983 ◽  
Vol 40 (5) ◽  
pp. 637-643 ◽  
Author(s):  
C. W. Pugsley ◽  
H. B. N. Hynes
Keyword(s):  
Vertical Distribution ◽  
Liquid Nitrogen ◽  
Benthic Invertebrates ◽  
Depth Distribution ◽  
Sampling Methods ◽  
Freezing Front ◽  
Southern Ontario ◽  
Freeze Core ◽  
Order Of Magnitude ◽  
The Vertical Distribution

A freeze-coring device using liquid nitrogen is described, which enables one person to take a columnar core, extending from the surface to at least 50 cm below a stony streambed. An experiment to validate the technique showed that animals did not flee from the advance of the freezing-front. Using frozen streambed cores, the vertical distribution of benthic invertebrates of two streams in southern Ontario was investigated. In contrast to previous estimates,~70% of the fauna was found in the top 10 cm of the streambed, and invertebrate densities were often lower by an order of magnitude. These differences are attributed to problems of quantifying previous sampling methods.

scholarly journals Typology and characterization of the pampean beekeeping systems

2020 ◽  
Vol 51 (2) ◽  
pp. 299-318
Author(s):  
Tomás Bragulat ◽  
Elena Angón ◽  
Alberto Giorgis ◽  
José Perea
Keyword(s):  
Cluster Analysis ◽  
Factor Analysis ◽  
Rural Areas ◽  
Export Market ◽  
Multivariate Techniques ◽  
High Productivity ◽  
Selection Of Variables ◽  
Socially Relevant ◽  
And Cluster Analysis ◽  
Random Survey

Objective: Identify and characterize the beekeeping systems of La Pampa (Argentina) using multivariate techniques based on the main structural, productive and economic characteristics. Methodology: The data was collected through a random survey of 80 beekeepers. The classification and description of the apicultural systems was based on a multivariate sequence comprising three stages: review and selection of variables, factor analysis and cluster analysis. Results: Factor analysis revealed that the size of the farm and the productive and economic performance of beekeeping jointly explained 66% of the variability. Through cluster analysis, three types of beekeeping have been identified: (i) Subsistence beekeeping grouped 55% of the farms, mainly characterized by small sizes and low productive and economic yields. (ii) Industrial beekeeping concentrated 54% of production in 15% of farms, mainly characterized by large sizes and high productive and economic yields. (iii) Commercial beekeeping grouped 30% of the farms, mainly characterized by high productivity with intermediate sizes. Limitations: The study has been carried out on a few farms due to the difficulty of obtaining answers to all the variables included in the survey. Practical implications: Beekeeping in La Pampa is generally a highly heterogeneous complement of income or family subsistence, with low productivity and low input use. Subsistence beekeeping is a socially relevant system for its contribution to family employment and income in rural areas. Industrial beekeeping is oriented to the export market and has a more competitive scale. Commercial beekeeping is situated on an intermediate scale.

scholarly journals Behavioral patterns of consumers participating in food safety and social co-governance: consumption choices and environmental improvement

2019 ◽  
Vol 131 ◽  
pp. 01086
Author(s):  
Menghui Qiu ◽  
Zhijing Zhao
Keyword(s):  
Cluster Analysis ◽  
Factor Analysis ◽  
Food Safety ◽  
Behavioral Patterns ◽  
Chinese Consumers ◽  
Consumption Choices ◽  
The Social ◽  
The Government ◽  
And Cluster Analysis ◽  
Behavior Models

Consumers are the most direct stakeholders of food safety, and their effective participation is the key to the social Co-governance of food safety. Based on the specific behaviors of Chinese consumers participating directly and indirectly in the social Co-governance of food safety, using the data of 350 consumers’ behavior survey and factor analysis and cluster analysis, this paper extracts two kinds of behavior models of Chinese consumers participating in the social Co-governance of food safety, namely, consumption choices model and environment improvement model. It is found that Chinese consumers are inclined to adopt the “environment improvement” model at this stage, which is the inevitable result of the current food safety pressure in China. The government should formulate corresponding policies to better guide consumers to participate in the social Co-governance of food safety.

Typology of online shoppers

2003 ◽  
Vol 20 (2) ◽  
pp. 139-156 ◽  
Author(s):  
Ah Keng Kau ◽  
Yingchan E. Tang ◽  
Sanjoy Ghose
Keyword(s):  
Cluster Analysis ◽  
Factor Analysis ◽  
Information Seeking ◽  
Online Shopping ◽  
Demographic Information ◽  
Buying Behavior ◽  
Internet Users ◽  
Online Shoppers ◽  
And Cluster Analysis ◽  
Online Buying

This article aims to examine the online buying behavior among a group of Internet users. Based on a sample of over 3,700 Internet users, this study explores their information‐seeking patterns as well as their motivations and concerns for online shopping. Factor analysis and cluster analysis were used to classify the respondents into six types of online shoppers. Coupled with their demographic information and actual buying behavior, it was possible to constitute a distinct profile for each of the segments. Discriminant analysis was also conducted to seek out the important attitudinal variables that differentiated the various clusters of online shoppers. The implications of such classification are also discussed.

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