Aarhus University Seal / Aarhus Universitets segl

PhD-defense: Can we accurately estimate soil engineering properties from spectroscopy and water content of air dry soils?

On Wednesday, June 10, Hafeez Ur Rehman defends his PhD thesis at the Department of Agroecology. Here he will talk about how to estimate soil engineering properties from 36 different countries.

2020.06.03 | Camilla Brodam

Photo: Hafeez Ur Rehman

During his PhD studies, Hafeez Ur Rehman has researched the development of rapid methods for estimating soil engineering properties because knowledge of the soil's technical properties is important in relation to shear strength, bearing capacity and tillage operations in soil.


In order to estimate the soil properties, Hafeez Ur Rehman has researched the use of visible near-infrared spectroscopy (Vis-NIRS) and hydroscopic water content measured by a so-called "Vapor sorption analyzer." The latter is a technique in which a sample is subjected to different conditions of humidity and temperature and the response of the sample is measured gravimetrically.


“It is easy to measure both Vis-NIRS and hygroscopic water content. With Vis − NIRS and hygroscopic water content, I accurately estimated the Atterberg boundaries and cation exchange capacity based on a uniform dataset, thus outperforming the pedotransfer functions. The hygroscopic water content predicted the Atterberg boundaries and cation exchange capacity better than Vis − NIRS and pedotransfer functions because soil engineering properties are primarily controlled by clay mineralogy and surface area,” Hafeez Ur Rehman says.

Hafeez Ur Rehman's research and findings provides a rapid alternative for estimation of soil-engineering properties for large-scale studies.

About the defense

Time: Wednesday 10 June 2020 at 10:00 
Place: Will be held online. To receive a link to the event, please send an e-mail to kch@agro.au.dk 
Title of PhD thesis: Estimating soil engineering properties from visible & near-infrared spectral data and hygroscopic water content
Contact information: Hafeez Ur Rehman, e-mail: hafeez@agro.au.dk, tel.: +45 91781087
Members of the assessment committee:
Associate Professor César Maestre Guerrero, Agrochemistry and Environment, Miguel Hernández University of Elche, Spain
Professor Abdul M Mouazen, Environment, Ghent University, Belgium
Senior scientist Lars Elsgaard, Department of Agroecology, Aarhus University (chair)
Main supervisor:
Professor Lis Wollesen de Jonge, Department of Agroecology, Aarhus University
Co-supervisor:
Researcher Emmanuel Arthur,  Department of Agroecology, Aarhus University
Researcher Maria Knadel, Department of Agroecology, Aarhus University
Language: The PhD dissertation will be defended in English

The defence is public.

Due to the coronavirus situation, Aarhus University is physically closed. Therefore, the PhD thesis will not be available for reading at the offices of the PhD administration. Instead, interested parties may send an e-mail to gradschool.tech@au.dk, and receive a digital copy of the PhD thesis. Please note, it may in certain cases be necessary to make an individual arrangement to read the PhD thesis.   



People, Agro