scholarly journals Evaluating the Influence of Rain Event Characteristics on Rainfall Interception by Urban Trees Using Multiple Correspondence Analysis

Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2659
Author(s):  
Katarina Zabret ◽  
Mojca Šraj
Keyword(s):  
Correspondence Analysis ◽  
Multiple Correspondence Analysis ◽  
Regression Trees ◽  
Pinus Nigra ◽  
Rainfall Amount ◽  
Urban Trees ◽  
Boosted Regression Trees ◽  
Rain Event ◽  
Rainfall Interception ◽  
Pine Tree

Urban trees play an important role in the built environment, reducing the rainfall reaching the ground by rainfall interception. The amount of intercepted rainfall depends on the meteorological and vegetation characteristics. By applying the multiple correspondence analysis (MCA), we analysed the influence of rainfall amount, intensity and duration, the number of raindrops, the mean volume diameter (MVD), wind speed and direction on rainfall interception. The analysis was based on data from 176 events collected over more than three years of observations. Measurements were taken under birch (Betula pendula Roth.) and pine (Pinus nigra Arnold) trees located in an urban park in the city of Ljubljana, Slovenia. The results indicate that rainfall interception is influenced the most by rainfall amount and the number of raindrops. In general, the ratio of rainfall interception to gross rainfall decreases with longer and more intense rainfall events. The influence of the raindrop number depends also on their size (MVD), which is evident especially for the pine tree. For example, pine tree interception increases with smaller raindrops regardless of their number. In addition, MCA gives a new insight into the influence of wind characteristics, which was not visible using previous methods of data analysis (regression analysis, correlation matrices, regression trees, boosted regression trees). According to the nearby buildings, a wind corridor is sometimes created, decreasing rainfall interception by both tree species.

Application of the multiple correspondence analysis for the evaluation of rain event characteristics influence on rainfall interception

2020 ◽  
Author(s):  
Katarina Zabret ◽  
Mojca Šraj
Keyword(s):  
Wind Speed ◽  
Correspondence Analysis ◽  
Multiple Correspondence Analysis ◽  
Pinus Nigra ◽  
Rainfall Amount ◽  
Rain Event ◽  
Rainfall Interception ◽  
Multivariate Statistical ◽  
Pine Trees ◽  
The Relationship

<p>Rainfall interception by birch (<em>Betula pendula</em> Roth.) and pine (<em>Pinus nigra</em> Arnold) trees was measured in small urban park in the city of Ljubljana, Slovenia from beginning of the year 2014. Three and a half years of measurements of throughfall, stemflow and rainfall in the open were analyzed to estimate the influence of rain event characteristics on rainfall interception. A new approach using multiple correspondence analysis (MCA) was implemented. MCA is a multivariate statistical method for descriptive rather than quantitative variables, and can be used to estimate the relationship between the variables. The results are presented using diagrams, in which the proximity of the variables corresponds to their interdependence and the location of the variables (positive or negative domain) corresponds to their positive or negative correlation. The analysis included information from 176 events, showing the relationship between rainfall interception of birch and pine trees and rainfall amount, duration and intensity, wind speed and direction, drop number and median volume diameter (MVD), expressing raindrop size. The numerical values of the variables were transformed to the descriptive ones using classes regarding the threshold values of the variables (more or less than threshold), which was determined through sensitivity analysis. The thresholds were 6 mm for rainfall amount, 4 h for duration and 1.8 mm/h for intensity, 1.3 m/s for wind speed, 8 cardinal directions for wind direction, 1.5 mm for MVD and 10,000, 50,000 and 100,000 raindrops for their number. The MCA again showed the dominant influence of the rainfall amount, as the ratio of rainfall interception to rainfall amount decreases with increasing rainfall amounts. MCA including the wind characteristics gave a new insight into its influence on rainfall interception. The results expressed two new directions of occasional wind corridor according to the nearby buildings which were not visible using other methods of data analyses. The presented analysis, using MCA, confirmed results of previous analyses using other methods and offered a new insights into the process.</p>

scholarly journals Informed Geoheritage Conservation: Determinant Analysis Based on Bibliometric and Sustainability Indicators Using Ordination Techniques

Land ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 539
Author(s):  
Boglárka Németh ◽  
Károly Németh ◽  
Jon N. Procter
Keyword(s):  
Correspondence Analysis ◽  
Conservation Planning ◽  
Earth Science ◽  
Multiple Correspondence Analysis ◽  
Contributing Factors ◽  
Usual Model ◽  
Development Indicators ◽  
Individual Variables ◽  
Business As Usual ◽  
World Development

Ordination methods are used in ecological multivariate statistics in order to reduce the number of dimensions and arrange individual variables along environmental variables. Geoheritage designation is a new challenge for conservation planning. Quantification of geoheritage to date is used explicitly for site selection, however, it also carries significant potential to be one of the indicators of sustainable development that is delivered through geosystem services. In order to achieve such a dominant position, geoheritage needs to be included in the business as usual model of conservation planning. Questions about the quantification process that have typically been addressed in geoheritage studies can be answered more directly by their relationships to world development indicators. We aim to relate the major informative geoheritage practices to underlying trends of successful geoheritage implementation through statistical analysis of countries with the highest trackable geoheritage interest. Correspondence analysis (CA) was used to obtain information on how certain indicators bundle together. Multiple correspondence analysis (MCA) was used to detect sets of factors to determine positive geoheritage conservation outcomes. The analysis resulted in ordination diagrams that visualize correlations among determinant variables translated to links between socio-economic background and geoheritage conservation outcomes. Indicators derived from geoheritage-related academic activity and world development metrics show a shift from significant Earth science output toward disciplines of strong international agreement such as tourism, sustainability and biodiversity. Identifying contributing factors to conservation-related decisions helps experts to tailor their proposals for required evidence-based quantification reports and reinforce the scientific significance of geoheritage.

scholarly journals Patterns of Italian high school and university students’ attitudes towards physics: an analysis based on semiotic-cultural perspective

2021 ◽  
Author(s):  
Italo Testa ◽  
Raffaele De Luca Picione ◽  
Umberto Scotti di Uccio
Keyword(s):  
High School ◽  
Cluster Analysis ◽  
University Students ◽  
Correspondence Analysis ◽  
Multiple Correspondence Analysis ◽  
Psychological Theory ◽  
Cultural Perspective ◽  
Undergraduate Level ◽  
Students Attitudes ◽  
And Cluster Analysis

AbstractThe purpose of this study was to analyse Italian high school and university students’ attitudes towards physics using the Semiotic Cultural Psychological Theory (SCPT). In the SCPT framework, attitudes represent how individuals interpret their experience through the mediation of generalized meaning with which they are identified. A view-of-physics questionnaire was used as an instrument to collect data with 1603 high school and university students. Data were analysed through multiple correspondence analysis and cluster analysis. We identified four generalized meanings of physics: (a) interesting and important for society; (b) a quite interesting, but badly taught subject at school and not completely useful for society; (c) difficult to study and irrelevant for society; and (d) a fascinating and protective niche from society. The identified generalized meanings are significantly correlated to the choice to study physics at undergraduate level and to the choice of attending physics-related activities in high school. Implications for research are discussed.

scholarly journals Effectiveness of mass treatment of Schistosoma mansoni infection in socially vulnerable areas of a state in northeastern Brazil, 2011–2014

2021 ◽  
Vol 79 (1) ◽  
Author(s):  
Flávia Silvestre Outtes Wanderley ◽  
Ulisses Montarroyos ◽  
Cristine Bonfim ◽  
Carolina Cunha-Correia
Keyword(s):  
Schistosoma Mansoni ◽  
Correspondence Analysis ◽  
Social Vulnerability ◽  
Multiple Correspondence Analysis ◽  
Vulnerability Index ◽  
Two Dimensions ◽  
Northeastern Brazil ◽  
Mass Treatment ◽  
Social Vulnerability Index ◽  
Treatment Information

Abstract Background To assess the effectiveness of mass treatment of Schistosoma mansoni infection in socially vulnerable endemic areas in northeastern Brazil. Method An ecological study was conducted, in which 118 localities in 30 municipalities in the state of Pernambuco were screened before 2011 and in 2014 (after mass treatment). Information on the endemic baseline index, mass treatment coverage, socio-environmental conditions and social vulnerability index were used in the multiple correspondence analysis. One hundred fourteen thousand nine hundred eighty-seven people in 118 locations were examined. Results The first two dimensions of the multiple correspondence analysis represented 55.3% of the variability between locations. The human capital component of the social vulnerability index showed an association with the baseline endemicity index. There was a significant reduction in positivity for schistosomes. For two rounds, for every extra 1% of initial endemicity index, the fixed effect of 13.62% increased by 0.0003%, achieving at most 15.94%. Conclusions The mass treatment intervention helped to reduce transmission of schistosomiasis in areas of high endemicity. Thus, it can be recommended that application of mass treatment should be accompanied by other control actions, such as basic sanitation, monitoring of intermediate vectors and case surveillance.

Generalized constrained multiple correspondence analysis

Psychometrika ◽  
2002 ◽  
Vol 67 (2) ◽  
pp. 211-224 ◽  
Author(s):  
Heungsun Hwang ◽  
Yoshio Takane
Keyword(s):  
Correspondence Analysis ◽  
Multiple Correspondence Analysis

scholarly journals Rainfall interception by six urban trees in San Juan, Puerto Rico

2018 ◽  
Vol 22 (1) ◽  
pp. 103-115 ◽  
Author(s):  
Christopher J. Nytch ◽  
Elvia J. Meléndez-Ackerman ◽  
María-Eglée Pérez ◽  
Jorge R. Ortiz-Zayas
Keyword(s):  
Puerto Rico ◽  
Urban Trees ◽  
San Juan ◽  
Rainfall Interception
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