Item


Testing Water Pollution in a Two Layer Aquifer

Water bodies around urban areas may be polluted with chemical elements from urban or industrial activities. We study the case of underground water pollution. This is a serious problem, since underground water is high qualified drinkable water in a world where this natural resource is increasingly reduced. This study is focused on a two-layer aquifer. If the superficial layer is contaminated, the deeper layer could be spoiled as well. This contribution checks the equality of the mean or centered composition of the two layers, with the aim of inferring their possible hydraulic conectivity. The data to be examined are different hydro-chemical components of water, such as nitrates and nitrites (related to nitrate/nitrite poisoning of animal stock), tensoactives (toxic to the ecosystem) or potassium (it promotes eutrophization of the water), represented in mg/l. As the data are compositional, we can group the pertinent elements and compare them applying ilr transformation. The ilr transformation is used for simplicity when comparing compositional vectors. MANOVA (Multivariate Analysis of Variance) is applied on the transformed data from the two layers. This provides a hypothesis test to discern whether the two aquifer layers can be considered a homogeneous continuum or, on the contrary, they should be considered as isolated layers. An illustrative example is presented. Used data sets, being synthetic, are inspired by a real case. These analyses suggest that the two aquifers are connected

Universitat de Girona. Departament d鈥橧nform脿tica i Matem脿tica Aplicada

Other contributions: Universitat de Girona. Departament d鈥橧nform脿tica i Matem脿tica Aplicada
Author: Garc铆a-Le贸n, M.
Lin, J.
Date: 2018 June 5
Abstract: Water bodies around urban areas may be polluted with chemical elements from urban or industrial activities. We study the case of underground water pollution. This is a serious problem, since underground water is high qualified drinkable water in a world where this natural resource is increasingly reduced. This study is focused on a two-layer aquifer. If the superficial layer is contaminated, the deeper layer could be spoiled as well. This contribution checks the equality of the mean or centered composition of the two layers, with the aim of inferring their possible hydraulic conectivity. The data to be examined are different hydro-chemical components of water, such as nitrates and nitrites (related to nitrate/nitrite poisoning of animal stock), tensoactives (toxic to the ecosystem) or potassium (it promotes eutrophization of the water), represented in mg/l. As the data are compositional, we can group the pertinent elements and compare them applying ilr transformation. The ilr transformation is used for simplicity when comparing compositional vectors. MANOVA (Multivariate Analysis of Variance) is applied on the transformed data from the two layers. This provides a hypothesis test to discern whether the two aquifer layers can be considered a homogeneous continuum or, on the contrary, they should be considered as isolated layers. An illustrative example is presented. Used data sets, being synthetic, are inspired by a real case. These analyses suggest that the two aquifers are connected
Document access: http://hdl.handle.net/2072/319399
Language: eng
Publisher: Universitat de Girona. Departament d鈥橧nform脿tica i Matem脿tica Aplicada
Rights: Tots els drets reservats
Subject: Aigua -- Contaminaci贸 -- Congressos
Water -- Pollution -- Congresses
Distribuci贸 (Teoria de la probabilitat) -- Congressos
Distribution (Probability theory) -- Congresses
Title: Testing Water Pollution in a Two Layer Aquifer
Type: info:eu-repo/semantics/conferenceObject
Repository: Recercat

Subjects

Authors


Warning: Unknown: write failed: No space left on device (28) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/var/lib/php5) in Unknown on line 0