Citation Rankings
Highly Cited Researchers
Africa Highly Cited Researchers CitationEngineering & Technology / Environmental Science & Engineering Rankings 2025
The Citation Rankings (Highly Cited Researchers) highlight the most cited and influential researchers across a vast range of scientific fields, covering 197 main and sub-disciplines, including the Art and Humanities Citation Rankings and Social Sciences and Humanities Citation Rankings. This service, offered exclusively by AD Scientific Index, aims to provide a balanced perspective by excluding data from CERN and other statistical sources that disproportionately favor certain researchers, particularly in the social sciences and humanities. This unique approach addresses the advantages researchers with multi-author publications and CERN involvement hold over others. Furthermore, citation rankings help uncover rule violations and unethical practices within the research community. For more detailed citation analyses, explore the Scientists Last 6 Years Citation Index, Universities Total Citations Rankings 2025, and Universities Last 6 Years Citations Rankings 2025.
* Total Citation Counts Rankings
Ranking Based On Selection :1
Climate Change
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
45,858
18,251
0.398
* Total Citation Counts Rankings
Ranking Based On Selection :2
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
23,833
11,807
0.495
* Total Citation Counts Rankings
Ranking Based On Selection :3
Wastewater Technology
Algal Biotechnology
Biofuels
Bioremediation
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
18,344
12,587
0.686
* Total Citation Counts Rankings
Ranking Based On Selection :4
enviornmental science
enviornmental biology
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
17,710
9,300
0.525
* Total Citation Counts Rankings
Ranking Based On Selection :5
Environmental Health
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
17,438
9,808
0.562
* Total Citation Counts Rankings
Ranking Based On Selection :6
Environmental Engineerning
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
16,170
5,000
0.309
* Total Citation Counts Rankings
Ranking Based On Selection :7
Wastewater treatment technologies
Bioreactors
Membrane technology
Water reuse
Microbial fuel
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
15,795
7,729
0.489
* Total Citation Counts Rankings
Ranking Based On Selection :8
Environmental Science and Technology
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
15,582
14,979
0.961
* Total Citation Counts Rankings
Ranking Based On Selection :9
Climate change
sustainability
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
15,059
5,654
0.375
* Total Citation Counts Rankings
Ranking Based On Selection :10
climate change mitigation
poverty
global stocktake
policy analysis
sustainable development
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
14,960
9,056
0.605
* Total Citation Counts Rankings
Ranking Based On Selection :11
Exposome
Diet and Respiratory disease
Air pollution and Respiratory Health
and Climate and Health
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
14,901
13,190
0.885
* Total Citation Counts Rankings
Ranking Based On Selection :12
climate change
risk
biodiversity
health
sustainability
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
12,569
12,221
0.972
* Total Citation Counts Rankings
Ranking Based On Selection :13
vulnerability
adaptation
climate change
development
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
12,073
6,946
0.575
* Total Citation Counts Rankings
Ranking Based On Selection :14
Environment and Education
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
11,200
1,908
0.170
* Total Citation Counts Rankings
Ranking Based On Selection :15
Environment Behaviour Studies
Housing and Environment
Architectural Education.
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,545
5,927
0.562
* Total Citation Counts Rankings
Ranking Based On Selection :16
Environmental Science
Reproductive Toxicology
Endocrine Disruption
Hepatotoxicity
Drug Toxicity
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,589
3,913
0.370
* Total Citation Counts Rankings
Ranking Based On Selection :17
Environment and Sustainable Development
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,504
2,315
0.220
* Total Citation Counts Rankings
Ranking Based On Selection :18
Climate Science
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,644
8,128
0.764
* Total Citation Counts Rankings
Ranking Based On Selection :19
Advanced Oxidation Processes
Ozone
UV
Electrolysis
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
9,906
3,484
0.352
* Total Citation Counts Rankings
Ranking Based On Selection :20
Climate Change
Livestock Systems
Pastoralism
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
9,093
4,804
0.528
* Total Citation Counts Rankings
Ranking Based On Selection :21
sustainability engineering
biogas
LCA
Future Technologies
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,808
6,968
0.791
* Total Citation Counts Rankings
Ranking Based On Selection :22
Adsorption
Water treatment
nanotechnology
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,375
4,612
0.551
* Total Citation Counts Rankings
Ranking Based On Selection :23
High Voltage Engineering
Lightning
EMI/EMC
Environmental Science
Extreme Natural Events
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,307
5,750
0.692
* Total Citation Counts Rankings
Ranking Based On Selection :24
Environment and Natural Resource Management
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,161
702
0.086
* Total Citation Counts Rankings
Ranking Based On Selection :25
Enviro-economic of Renewable Energy
Solar Thermal and PV
Agrivoltaics
Wind Energy
Desalination
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,062
4,996
0.620
* Total Citation Counts Rankings
Rankings
11,471
33
14
Ranking Based On Selection: 1
Mark New
University of Cape Town
Cape Town, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
45,858
18,251
0.398
* Total Citation Counts Rankings
Rankings
31,826
101
2
Ranking Based On Selection: 2
Charlie Shackleton
Rhodes University
Grahamstown, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
23,833
11,807
0.495
* Total Citation Counts Rankings
Rankings
45,806
149
1
Ranking Based On Selection: 3
Faizal Bux
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
18,344
12,587
0.686
Wastewater Technology
Algal Biotechnology
Biofuels
Bioremediation
* Total Citation Counts Rankings
Rankings
48,094
45
8
Ranking Based On Selection: 4
Mazharuddin Khan
Addis Ababa University
Addis Ababa, Ethiopia
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
17,710
9,300
0.525
enviornmental science
enviornmental biology
* Total Citation Counts Rankings
Rankings
49,146
14
1
Ranking Based On Selection: 5
Wilkister Nyaora Moturi
Egerton University
Njoro, Kenya
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
17,438
9,808
0.562
* Total Citation Counts Rankings
Rankings
54,350
182
37
Ranking Based On Selection: 6
George Ekama
University of Cape Town
Cape Town, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
16,170
5,000
0.309
Environmental Engineerning
* Total Citation Counts Rankings
Rankings
56,082
189
4
Ranking Based On Selection: 7
Ali Akbar Zinatizadeh
University of South Africa
Pretoria, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
15,795
7,729
0.489
Wastewater treatment technologies
Bioreactors
Membrane technology
Water reuse
Microbial fuel
* Total Citation Counts Rankings
Rankings
57,077
57
11
Ranking Based On Selection: 8
Adhena Ayaliew Werkneh
Mekelle University
Mekelle, Ethiopia
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
15,582
14,979
0.961
Environmental Science and Technology
* Total Citation Counts Rankings
Rankings
59,743
204
18
Ranking Based On Selection: 9
Barend Erasmus
University of Pretoria
Pretoria, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
15,059
5,654
0.375
Climate change
sustainability
* Total Citation Counts Rankings
Rankings
60,296
207
40
Ranking Based On Selection: 10
Harald Winkler
University of Cape Town
Cape Town, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
14,960
9,056
0.605
climate change mitigation
poverty
global stocktake
policy analysis
sustainable development
* Total Citation Counts Rankings
Rankings
60,556
59
12
Ranking Based On Selection: 11
Mulubirhan Assefa Alemayohu
Mekelle University
Mekelle, Ethiopia
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
14,901
13,190
0.885
Exposome
Diet and Respiratory disease
Air pollution and Respiratory Health
and Climate and Health
* Total Citation Counts Rankings
Rankings
75,418
260
51
Ranking Based On Selection: 12
Christopher Trisos
University of Cape Town
Cape Town, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
12,569
12,221
0.972
climate change
risk
biodiversity
health
sustainability
* Total Citation Counts Rankings
Rankings
79,169
275
56
Ranking Based On Selection: 13
Gina Ziervogel
University of Cape Town
Cape Town, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
12,073
6,946
0.575
vulnerability
adaptation
climate change
development
* Total Citation Counts Rankings
Rankings
86,715
308
6
Ranking Based On Selection: 14
Robson Mukwambo
Rhodes University
Grahamstown, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
11,200
1,908
0.170
Environment and Education
* Total Citation Counts Rankings
Rankings
93,199
109
1
Ranking Based On Selection: 15
Adewale Bukola Adejoke
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,545
5,927
0.562
Environment Behaviour Studies
Housing and Environment
Architectural Education.
* Total Citation Counts Rankings
Rankings
92,730
152
10
Ranking Based On Selection: 16
Mokhtar Ibrahim Yousef
Alexandria University
Alexandria, Egypt
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,589
3,913
0.370
Environmental Science
Reproductive Toxicology
Endocrine Disruption
Hepatotoxicity
Drug Toxicity
* Total Citation Counts Rankings
Rankings
93,579
28
1
Ranking Based On Selection: 17
Charles Kigen
Moi University
Eldoret, Kenya
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,504
2,315
0.220
Environment and Sustainable Development
* Total Citation Counts Rankings
Rankings
92,159
329
74
Ranking Based On Selection: 18
Christopher Lennard
University of Cape Town
Cape Town, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
10,644
8,128
0.764
* Total Citation Counts Rankings
Rankings
100,099
82
17
Ranking Based On Selection: 19
Joon Wun Kang
Addis Ababa University
Addis Ababa, Ethiopia
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
9,906
3,484
0.352
Advanced Oxidation Processes
Ozone
UV
Electrolysis
* Total Citation Counts Rankings
Rankings
110,321
38
4
Ranking Based On Selection: 20
Polly Ericksen
International Livestock Research Institute (ILRI)
Addis Ababa, Kenya
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
9,093
4,804
0.528
Climate Change
Livestock Systems
Pastoralism
* Total Citation Counts Rankings
Rankings
114,396
435
17
Ranking Based On Selection: 21
Charles Mbohwa
University of Johannesburg
Johannesburg, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,808
6,968
0.791
sustainability engineering
biogas
LCA
Future Technologies
* Total Citation Counts Rankings
Rankings
121,098
464
6
Ranking Based On Selection: 22
Maurice S. Onyango
Tshwane University of Technology
Pretoria, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,375
4,612
0.551
Adsorption
Water treatment
nanotechnology
* Total Citation Counts Rankings
Rankings
122,158
468
60
Ranking Based On Selection: 23
Chandima Gomes
University of the Witwatersrand
Johannesburg, South Africa
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,307
5,750
0.692
High Voltage Engineering
Lightning
EMI/EMC
Environmental Science
Extreme Natural Events
* Total Citation Counts Rankings
Rankings
124,586
45
1
Ranking Based On Selection: 24
Geoffrey Kamau
Africa Nazarene University
Nairobi, Kenya
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,161
702
0.086
Environment and Natural Resource Management
* Total Citation Counts Rankings
Rankings
126,281
32
2
Ranking Based On Selection: 25
Mohamed Akhsassi
Citation Metrics
Total
Last 6 Years
Last 6 Years / Total
8,062
4,996
0.620
Enviro-economic of Renewable Energy
Solar Thermal and PV
Agrivoltaics
Wind Energy
Desalination