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Prof. Yongxin Xu

Department Staff - Academic Staff

Senior Professor of Hydrogeology

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 Tel: +27 (0)21 959 3882

 Fax: +27 (0)21 959 3118

 Cell: +27 (0)82 7769612 

 Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

 


 

EDUCATION

Dec.77 - Jan.82:  BSc in hydrogeology & engineering geology from the Chengdu University of Technology, PRC

Feb.82 - Nov.84:  MSc in hydrogeology from the Chengdu University of Technology, PRC

Feb.96 - Sept.98:  PhD in geohydrology from the University of the Orange Free State, South Africa

PROFESSIONAL EXPERIENCE

07/2001- Present  Full Professor / Senior Professor of hydrogeology in Dept of Earth Sciences at the

                          University of the Western Cape, South Africa. And Chairholder of UNESCO Chair in

                          Geohydrology.

04/1999- 06/2001  Specialist Scientist and advisor, the National Department of Water Affairs and Forestry

                           (DWAF), Pretoria, South Africa Groundwater resource assessment and protection at

                           DWAF, Pretoria

08/1994- 03/1999  Principal Hydrologist, DWAF, Pretoria, South Africa

                           Groundwater quality management and research

03/1991- 07/1994  Principal Geohydrologist, DWAF, South Africa. Involved in Bophuthatswana Rural Water

                           Supply and aquifer assessment. Project Leader, geohydrologic supervisor & coordinator of

                           water resources development projects

03/1989- 02/1991  Principal Geologist in the Geological Survey in the former Republic of Bophuthatswana,

                          South Africa. Project leader for borehole siting, drilling supervision and pumping tests as

                          well as economic mineral exploration in the Southern Kalahari, Bophuthatswana, South

                          Africa

10/1987-03/1989  Visiting lecturer in the Department of Geological Sciences, University of Birmingham, UK.

                          Hydrogeochemical modelling and aquifer protection

12/1984-10/1987  Lecturer in the Department of Hydrogeology & Engineering Geology, Chengdu University of

                                 Technology, PRC. Areasof interest  included hydrogeology, hydrogeochemistry, environmental

                                 geology, and redbed

International  Short courses presented or facilitated (brief list)

  • SADC Groundwater recharge assessment held at UWC, as course leader with support by Dr Hans Beekman and Dr David Bredencamp, 25~27 Nov 2002.
  • Groundwater pollution for the UNEP and UNESCO held in Mombassa, Kenya, as course leader with support from Dr Brent Usher of  South Africa, 10~14 May 2004.
  • Surface and ground water interaction for UNEP 11 countries held at UWC, Cape Town, as course leader, 4~7 Oct 2004.
  • Effective Model Calibration with Analysis of Data Needs, Sensitivities, and Uncertainty held at UWC, Cape Town, South Africa, led by Mary C. Hill Claire R. Tiedeman and facilitated by Y Xu, 9-12 November 2004.
  • International fractured rock aquifers assessment held at UWC, Cape Town, South Africa, led by Dr Alan Shapiro of USGS with support by Y Xu and others, 22 – 24 Nov 2004.
  • Fractured rock aquifers assessment II held at UWC, Cape Town,  as course leader with support from Prof Gerrit van Tonder and Prof Eberhard Braune, 4 – 6 July 2005.
  • Introduction hydrochemistry held at UWC led by Dr Walt Kelly of USA and facilitated by Y Xu and others, 3~4 July 2006.
  • Geochemical and Reactive Transport Modelling PHREEQC, MT3DMS, PHT3D, held at UWC, led by Prof Chunmiao Zheng, Dr Henning Prommer and Dr Vincent Post, and  facilitated by Y Xu, 27 Nov ~1 Dec 2006.
  • Introductory Course on Groundwater Development held at UWC as course leader, April 2007 (1 day course).
  • Groundwater resources management for GWP Benin National Committee and the University of Abomey-Calavi, Benin, 4~8 May 2008.
  • Integrated Water Resources Management (IWRM) short course held at UWC, Cape Town, led by Prof Eberhard Brraune and co-presented by Y Xu and other, Sep 29~Oct 2 2008.
  • Numeric simulation of groundwater flow in partnership with University of Oslo held at UWC, Cape Town, as course leader with support from Prof C-Y Xu of Norway and Dr J Zhang of Canada. 9~12 June 2009.
  • 1st  SADC short course on Management of Aquifer Recharge held at UWC, Cape Town, led by Dr Peter Dillon of CSIRO and facilitated by Y Xu, 26 ~ 29 Oct 2009.
  • Salinity of coastal aquifer – monitoring, understanding and managing at UWC led by Dr Yoseph Yechieli of Israel Geological Survey and facilitated by Y Xu, 20 - 22 July 2010
  • Geochemistry and contaminant transport modeling held in Lagoon Beach Hotel, Cape Town, led by Prof Josef Zeman and Prof Nada Rapantova and facilitated by Y Xu, 16~18 May 2011.
  • Estimating groundwater recharge, held in Eskom club, Bellville, Cape Town, led by Dr R Healy and Dr B Scanlon, organized by Africa Groundwater Academy and facilitated by Y Xu, 14~16 Nov 2011

Invited PowerPoint Presentations

  • A guest speaker on groundwater pollution in South Africa at Afriwast’97 (Jan. 1997).
  • A guest speaker (co-presenter) on on-site sanitation and protection for a conference of the Water Institute of Southern Africa (July 1997).
  • An Integrated Approach to Groundwater Development and Management - A perspective of TMG aquifer, presented at ESA & UNESCO Tiger Initiative workshop held in Pretoria, on 10 November 2004.
  • Sustainable yield assessment for Golder & Associates in Perth, Australia, 3 Dec 2005.
  • Approaches to fractured rock aquifer characteristics – a TMG perspective
  1. At BGR, Hanover, Germany, March 2007.
  2. At ITC the Netherlands, March 2007.
  3. In Namibia Department of Water Affairs, April 2007.
  4. The guest speaker at the year end function of IAH Brisbane Branch, 11 December 2007.
  • Groundwater Management in Africa co-presented to the AMCOW (African Minister’s Council on Water) at the 6th Ordinary Session of AMCOW held in Brazzaville on 30 May, 2007. And follow-up presentations include:
  1. The session of “Transboundary aquifers in Africa” during Stockholm World Water Week, August 2007.
  2. UNEP, UNESCO & UWC session on “Africa groundwater management and protection” at the IAH conference, Lisbon September 2007.
  3. A keynote speaker at workshop of “Groundwater commission for Africa” during the AMCOW meeting in November 17 ~ 18 2007.
  4. 3rd UNESCO ISARM conference held in Tripoli, 25 ~ 27 May 2008.
  • Aquifer vulnerability assessment at the National University of Mar del Plata, Argentina, 6 Dec 2007.
  • Workshop on “Climate change and groundwater – the forgotten sink” presented at the Queensland University of Technology, Brisbane on 13 December, 2007. And a LIVE Radio Interview by Ms Leonie Lyon of ABC (Western Station).
  • Integrated Water Resources Management: Groundwater for development
  1. UNESCO IHP International Conference held in Cape Town in 9 ~ 13 March 2008
  2. 1st Africa Water Week held in Tunis in 26 ~ 29 March 2008.
  • Seminar on Global water resources organized by Water Programme of InterAcademic Council, 21~22 Nov 2009, Beijing
  1. Water resources issues in developing countries --- an Africa perspective
  • Groundwater recharge estimation in southern Africa presented for Academic Committee Meeting for at UNESCO International Karst centre in Guilin, China, 3~4 Dec 2011.

Professional Services

  • An adjunct instructor on groundwater courses in the Department of Engineering Geology and Department of Civil Engineering at the University of Pretoria for the years 1995-1998.
  • An adjunct Professor in School of Natural Resource Sciences, Faculty of Science, at the Queensland University of Technology, Brisbane (2003~present). (http://src.sci.qut.edu.au/programs/ews/members.jsp)
  • South African Leader of VLIR Water Project under Flemish IUC-UWC Programme.
  • South African Project Leader of the UNESCO cross-cutting Project for integrated management of water resources and ecosystems in Africa.
  • Advisor and Co-ordinator for a UNEP & UNESCO project titled “Assessment of pollution status and vulnerability of water supply aquifers of African cities” (2002~2006).
  • Member, International Professionals for the Advancement of Chinese Earth Sciences (IPACES), the membership is by invitation only.
  • A member of Academic Committee of UNESCO International Center on Karst, Guilin, China (2008~2012).
  • Associate Editor for Hydrogeology Journal, Official Journal of the International Association of Hydrogeologists from 2005 to 2009.
  • Associate Editor for Journal of Yangtze River Scientific Research Institute, ISSN 1001-5485.
  • A Guest Editor for the special section: Groundwater in Africa, Ground Water, March 2010.
  • Advisor on academic publishing, CRC Press and Balkema (Taylor & Francis Group).
  • A commissioner of the Africa Groundwater Commission of AMCOW (Africa’s ministerial council on water).
  • A member of Technical Advisory Committee of the International Groundwater Resources Assessment Center (IGRAC), UNESCO, The Netherlands.

PUBLICATIONS

Scientific Papers:

1986 Y. Xu & T. Ren "The Condition of Water-bearing Space Development in the Redbed Mudstone Aquifer in Hengyang Basin",  Journal of Chengdu College of Geology, PRC, ISSN 0256-2197, Vol.13 No.2.

1988 Y. Xu & L. Fengyi "Thermodynamic Analysis of Reaction Mechanism of Precipitation of Calcium Carbonate of Karst-porous Water in the Red-bed of Hengyang Basin", Hydrogeology & Engineering Geology, PRC, Vol.1988, No. 1(99), P.32-34.

1991 Y. Xu, S. Marais & L. McCaffrey "A Preliminary Discussion of Aquifer Protection Strategies for Some Areas in Bophuthatswana", Groundwater Quality and Pollution, ISBN-0-620-15829-8, Biennial Ground Water Convention, South Africa, 21- 13 August 1991.

1992 K. Pelpola, P. Pienaar & Y. Xu "Development of Groundwater Resources in Bophuthatswana", Water, Environment and Management, ISBN 0 906055 29 6, Proceedings of the 18th WEDC Conference at Kathmandu, Nepal 30 Aug.-3rd Sept. 1992.

1993 Y. Xu, F. Ma & T.C. Partridge "Time Series Analysis of the Rainfall, Piezometric Fluctuations and Spring Flow in the Dolomitic Aquifer System of Wondergat-Dinokana Area, North East of Mafikeng", Africa Needs Ground Water, ISBN 0-620-17821-3 Vol 2, An International Groundwater Convention at University of the Witwatersrand, Johannesburg, RSA, 6-8 Sept. 1993.

1995 Y. Xu & A.G. Reynders "A three-tier approach to protect groundwater resources in South Africa", ISSN 0378-4738,  Water SA, Vol.21 No. 3 July 1995.

1995 Y. Xu & E. Braune "Minimum distance as an important concept for borehole source protection in South Africa", Conference Papers of Ground Water'95 held at Volkswagen Conference Centre, Midrand, South Africa, 26-28 September 1995, ISBN:  0-620-19572-X.

1997 Y. Xu, G.J. van Tonder, B. van Wyk, E. van Wyk & B. Aleobua "Borehole dilution experiment in a Karoo aquifer in Bloemfontein", ISSN 0378-4738,  Water SA, Vol.23 No. 2 April 1997.

1997 Y. Xu, G.J. van Tonder, B. van Wyk. and , E. van Wyk "Approximate analytical solutions to tracer experiment under pumping condition", 8th South African National Hydrology Symposium Proceedings, 17-19 November 1997, Pretoria,  ISSN 0-620-21927-0.

1998 Y. Xu, G.J. van Tonder, B. van Wyk. and , E. van Wyk "Recharge-incorporated approximate solution to tracer experiment under pumping condition", ISSN 0378-4738,  Water SA, Vol.24 No. 1 January 1998.

2000 K. Wright and Y. Xu "A water balance approach to the sustainable management of groundwater in south africa", ISSN 0378-4738,  Water SA, Vol.26 No. 2 April 2000.

2000 Y. Xu, E. Braune, C. Colvin, D. le Maitre, K. Pietersen and T. Hotom "Comprehensive determination of resource directed measures for groundwater in South Africa", In Groundwater: Past Achievements and future challenges, Sililo et al (eds.), Balkema, Rotterdam (ISSN 905809 1597).

2001 J.G. van Tonder, J.F. Botha, W.H. Chiang, H. Kunstmann and Y. Xu "Estimation of the sustainable yields of boreholes in fractured rock formations", ISSN 0378-4738,  Journal of Hydrology, 241 70-90.

2001 Y. Xu and G.J. van Tonder "Estimation of recharge using a revised CRD method", ISSN 0378-4738,  Water SA, Vol.27 No. 3 July 2001.

2002 Y. Xu and G.J. van Tonder "Capture zone simulation for boreholes located in fractured   dykes using the linesink concept", ISSN 0378-4738,  Water SA, Vol.28 No. 2 April 2002.

2002 Y. Xu, R Titus, SD Holness, J Zhang and G.J. van Tonder "A hydrogeomorphological approach to quantification of groundwater discharge to streams in South Africa", ISSN 0378-4738,  Water SA, Vol.28 No. 4 October 2002.

2003 Beekman EH & Xu Y “Review of groundwater recharge estimation in arid and semi-arid Southern Africa” in Xu & Beekman (Eds) “Groundwater recharge estimation in Southern Africa”, UNESCO IHP Series No. 64, published by UNESCO Paris. ISNB 92-9220-000-3.

2003 Bredenkamp DB & Xu Y “Perspectives on recharge estimation in dolomitic aquifers in South Africa” in Xu & Beekman (Eds) “Groundwater recharge estimation in Southern Africa”, UNESCO IHP Series No. 64, published by UNESCO Paris. ISNB 92-9220-000-3.

2003 Xu Y & Beekman EH  “A box model for estimating recharge – the RIB method” in Xu & Beekman (Eds) “Groundwater recharge estimation in Southern Africa”, UNESCO IHP Series No. 64, published by UNESCO Paris. ISNB 92-9220-000-3.

2003 Xu Y & Maclear LGA  “Recharge estimation in fractured rock aquifer from rainfall – spring flow comparisons: the Uitenhage Spring case” in Xu & Beekman (Eds) “Groundwater recharge estimation in Southern Africa”, UNESCO IHP Series No. 64, published by UNESCO Paris. ISNB 92-9220-000-3.

2003 Xu Y, Wu Y & Beekman EH  “The role of interflow in estimating recharge in mountainous catchments” in Xu & Beekman (Eds) “Groundwater recharge estimation in Southern Africa”, UNESCO IHP Series No. 64, published by UNESCO Paris. ISNB 92-9220-000-3.

2004 Jovanovic, N.Z., Maharaj, S., Xu, Y., Jia, H., Titus, R., Usher, B., Dennis, I., Pretorius, J. & Cave, L. Prioritization and risk assessment of groundwater contaminants in South African urban catchments. In: V. Popov, H. Itoh, C.A. Brebbia and S. Kungolos (eds.) Waste Management and the Environment II, 605-614. Wit Press, Southampton, UK.

2005 Wu Y & Xu Y “Snow impact on groundwater recharge in Table Mountain Group aquifer systems with a case study of the Kommissiekraal River catchment South Africa”. ISSN 0378-4738,  Water SA, Vol.31 No. 3 July 2005.

2006 Lin L & Xu Y “A tensor approach to the estimation of hydraulic conductivities in Table Mountain Group aquifers of South Africa”. ISSN 0378-4738,  Water SA, Vol.32 No. 3 July 2006.

2006 Seward P, Xu Y & Brendonck L “Sustainable groundwater use, the capture principle, and adaptive management”. ISSN 0378-4738,  Water SA, Vol.32 No. 4 October 2006.

2006 Xu Y & Usher BH  “Issues of groundwater pollution in Africa” in Xu & Usher (Eds) “Groundwater pollution in Africa”, Taylor & Francis Group plc, London, UK. ISBN 10: 0-415-41167-x, ISBN 13: 978-0-415-41167-7 and ISBN 10: 92-807-2680-3.

2006 Adelana SMA & Xu Y  “Contamination and protection in the Cape Flats Aquifer, South Africa” in Xu & Usher (Eds) “Groundwater pollution in Africa”, Taylor & Francis Group plc, London, UK. ISBN 10: 0-415-41167-x, ISBN 13: 978-0-415-41167-7 and ISBN 10: 92-807-2680-3.

2006 Braune E & Xu Y  “A South African perspective on the protection of groundwater resources” in Xu & Usher (Eds) “Groundwater pollution in Africa”, Taylor & Francis Group plc, London, UK. ISBN 10: 0-415-41167-x, ISBN 13: 978-0-415-41167-7 and ISBN 10: 92-807-2680-3.

2007 Els R. De Roeck, Bram J. Vanschoenwinkel, Jenny A. Day, Yongxin Xu, Lincoln Raitt, and Luc Nrendonck “Conservation status of large branchiopods in the Western Cape, South Africa”, Wetlands, Vol. 27, No. 1, March 2007, pp. 162-173

2007 Lin L, Jia H and Xu Y “Fracture network characteristics of a deep borehole in the Table Mountain Group (TMG), South Africa”, Hydrogeology Journal, Vol. 15, No. 7, November 2007

2008 Roets W, Xu Y, Raitt L and  & Brendonck L “Groundwater discharges to aquatic ecosystems associated with the Table Mountain Group (TMG) aquifer: A conceptual model”. ISSN 0378-4738,  Water SA, Vol.34 No. 1 January 2008

2008 Yongxin Xu,  “Editor’s message: building capacity and partnerships towards sustainable utilization of groundwater in Africa”, Hydrogeology Journal, Vol. 16, No. 3, May 2008

2008 W Woets, Y Xu, L Raitt, M El-Kahloun, P Meire, F Calitz, O Batelaan, C Anibas, K Paridaens, T Vandenbroucke, N E C Verhoest and L Brendonck  “Determining discharges from the Table Mountain Group (TMG) aquifer to wetlands in the Southern Cape, South Africa”, Hydrobiologia (2008) 607: 175-186, DOI 10.1007/s10750-008-9389-x, Springer

2008 Eberhard Braune and Yongxin Xu, “Groundwater management issues in southern Africa – an IWRM perspective”, Water SA (2008) ISSN 0378-4738 = Water SA Vol. 34 No. 6 (IWRM Special Edition) 2008, ISSN 1816-7950 = Water SA (on-line), Available on website http://www.wrc.org.za.

2009 Jaco Nel, Yongxin Xu, Okke Batelaan and Luc Brendonck  “Benefit and implementation of groundwater protection zoning in South Africa”, Water Resource Manage (2009) DOI 10.1007/s11269-009-9415-4, Springer.

2009 Eberhard Braune and Yongxin Xu “The role of Ground Water in Sub-Saharan Africa”, Ground Water (2009) DOI 11111/j.1745-6584.2009.00557.x, USA National Ground Water Association.

2009 Kenneth R. Bradbury and Yongxin Xu. “Foreword to Special Section: Groundwater in Africa”, Ground Water (2009) DOI 10.1111/j.1745-6584.2009.00658.x, USA National Ground Water Association.

2010 Yongxin Xu, Thokozani Kanyerere, Eberhard, Braun, Jaco Nel, Phil Hobbs, Kenneth Bradbury and Nick Robins. “Best practice for groundwater quakity protection”, In Y Xu & E Braune (Eds) “Sustainable groundwater resources in Africa: water supply and sanitation environment” (in press). Published by Taylor & Francis / Balkema, ISBN Hardback: 978 0 41587603 2, ISBN e-Back: 978 0 203 85945 2, The Netherlands and UK.

2010 Josue Bahati Chishugi and Yongxin Xu. “Water supply and sanitation in the Democratic Republic of the Congo”, ”, In Y Xu & E Braune (Eds) “Sustainable groundwater resources in Africa: water supply and sanitation environment”. Published by Taylor & Francis / Balkema, ISBN Hardback: 978 0 41587603 2, ISBN e-Back: 978 0 203 85945 2, The Netherlands and UK.

2010 Yasmin Rajkumar and Yongxin Xu. “Preserving groundwater quality against microbiological contamination through differentiated aquifer management in Africa”, In Y Xu & E Braune (Eds) “Sustainable groundwater resources in Africa: water supply and sanitation environment”. Published by Taylor & Francis / Balkema, ISBN Hardback: 978 0 41587603 2, ISBN e-Back: 978 0 203 85945 2, The Netherlands and UK.

2011 Yasmin Rajkumar and Yongxin Xu. “Protection of borehole water quality in sub-Saharan Africa using minimum safe distances and zonal protection”, Water Resource Manage, Volume 23 No 4, March 2011, ISSN 0920-4741, Springer.

2011 Yongxin Xu. “Book review: Estimating groundwater recharge, by Richard W Healy (Cambridge University Press, 2010)”, Hydrogeology Journal (2011) DOI 10.1007/s10040-011-0764-8, Springer.

2011 Jonathan Levy and Yongxin Xu. “Review: Groundwater management and groundwater/surface-water interaction in the context of South African water policy”, Hydrogeology Journal (2011) DOI 10.1007/s10040-011-0776-4, Springer.

Books:

1995 Y. Xu & E. Braune "A guideline for groundwater protection for the community water supply and sanitation programme", Published by the Department of Water Affairs and Forestry, RSA, ISBN: 0-621-16787-8.

2003 Y. Xu & H E. Beekman (Eds) “Groundwater recharge estimation in Southern Africa”, UNESCO IHP Series No. 64, published by UNESCO Paris. ISNB 92-9220-000-3.

2006 Y Xu & B Usher (Eds) “Groundwater Pollution in Africa”. Published by Taylor & Francis / Balkema, ISBN 10: 0-415-41167-X. UK

2010 Y Xu & E Braune (Eds) “Sustainable groundwater resources in Africa: water supply and sanitation environment”, published by Taylor & Francis / Balkema, ISBN Hardback: 978 0 41587603 2, ISBN e-Back: 978 0 203 85945 2, The Netherlands and UK

Software developed and distributed:

FC-Method as referred to in “A guide for the interpretation of pumping tests and estimation of sustainable yields of boreholes in fractured-rock aquifers” by GJ van Tonder and Y Xu, the technical report No. GH 3927 of the Department of Water Affairs and Forestry, February 1999.

AquaTest. A normal analysis tool for pumping tests has many more practical applications including 1) type curve fitting, 2) effective radius simulations, 3) derivative calculations and 4) estimation of sustainable borehole yields.

HAM stands for Hydrogeochemical Assessment Model in Excel. A course, organised by the Cape Groundwater Division of the Geological Society of South Africa, was presented by Y Xu and G Tredoux, at the CSIR, Stellenbosch on August 13, 1999.

AquaCel is a 2D flow model using spreadsheet best for conceptual thinking and educational Purposes, the AquaCel was released by the Scientific GroundWaterMan, August 1999.

REME is a Recharge Estimation Model using Excel VBA, which was presented at the Recharge Course in Cape Town organised by the Department of Earth Sciences at the University of Western Cape from 19-21/6/2000.

Rainfall Generator. This program is used to generate random rainfall events based on existing time series recorded for a period of time. The newly generated time series would be characterized by the same statistics as the existing one.

BoreholeLogging. This it used to capture information on geology and water strikes by presenting a user friendly logging profile.

Baseflow Separation. The program is based a geomorphological approach  (Xu et al., 2002).

BoxModels (Jia & Xu). This program is designed to interpret the natural tracer breakthrough curves like Chloride (Cl), Tritium (3H) and Carbon-14 (14C) etc.

PhD Students supervised

Name-----------in Subject----------(year of completion)-----------Present address----------------------

Rian Titus in Basement aquifer (2003): Director, Water Geosciences Consulting, Pretoria

Kevin Pietersen in Groundwater management (2004): Director, Water Geosciences Consulting, Pretoria

Shafick Adams in Recharge in basement aquifer (2004): Research Manager, South Africa Water Research Commission, Pretoria

Yong Wu in Groundwater recharge (2005): Professor of Hydrogeology at the Chengdu University of Technology, China

Haili Jia in Aquifer storage (2006): Senior Hydrogeologist, Water Division of Council of Geosciences, Pretoria

Lixiang Lin in Fracture rock aquifers (2007): Specialist Scientist in Hydrogeology, Water Division of Council of Geosciences, Pretoria

Wetsche Roets in Ecohydrology (2009): National Parks Board, George, South Africa

Harrison Pienaar in Groundwater resources management (2009): Competent Area Manager, CSIR, Pretoria

Segun Adelana in Cape Flats Aquifer management (2010): Nigeria

Jaco Nel in Groundwater protection (2011): Groundwater Services Consulting, Johannesburg

Anthony Duah in Groundwater resources management (2012): Senior Researcher, CSIR, Ghana

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