Johan U. Grobbelaar

4.0k total citations · 1 hit paper
64 papers, 2.7k citations indexed

About

Johan U. Grobbelaar is a scholar working on Renewable Energy, Sustainability and the Environment, Oceanography and Environmental Chemistry. According to data from OpenAlex, Johan U. Grobbelaar has authored 64 papers receiving a total of 2.7k indexed citations (citations by other indexed papers that have themselves been cited), including 32 papers in Renewable Energy, Sustainability and the Environment, 17 papers in Oceanography and 17 papers in Environmental Chemistry. Recurrent topics in Johan U. Grobbelaar's work include Algal biology and biofuel production (32 papers), Aquatic Ecosystems and Phytoplankton Dynamics (16 papers) and Marine and coastal ecosystems (16 papers). Johan U. Grobbelaar is often cited by papers focused on Algal biology and biofuel production (32 papers), Aquatic Ecosystems and Phytoplankton Dynamics (16 papers) and Marine and coastal ecosystems (16 papers). Johan U. Grobbelaar collaborates with scholars based in South Africa, Germany and Czechia. Johan U. Grobbelaar's co-authors include D.P. Sartory, Ladislav Nedbal, Carl J. Soeder, Vladimír Tichý, Amos Richmond, Fusheng Xiong, Norihide Kurano, Paul Hartig, Joost Groeneweg and P. Stegmann and has published in prestigious journals such as SHILAP Revista de lepidopterología, Water Research and Bioresource Technology.

In The Last Decade

Johan U. Grobbelaar

64 papers receiving 2.5k citations

Hit Papers

align trajectories

What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

Extraction of chlorophyll a from freshwater phytoplankton for spectrophotometric analysis

1984 790 citations Johan U. Grobbelaar et al. Hydrobiologia profile →

Peers

Johan U. Grobbelaar

RESE

OCEAN

ECOLO

G‐Yull Rhee United States

F. P. Healey Canada

Peter Williams United Kingdom

C. Nalewajko Canada

Armando Augusto Henriques Vieira Brazil

Virginia E. Villafañe Argentina

Rhena Schumann Germany

Jiunn‐Tzong Wu Taiwan

George P. Fitzgerald United States

Sverre Myklestad Norway

G‐Yull Rhee United States

Johan U. Grobbelaar

735 ×0.5

RESE

1.6k ×1.5

1.6k ×2.3

OCEAN

764 ×1.5

ECOLO

173 ×0.6

Citations per year, relative to Johan U. Grobbelaar Johan U. Grobbelaar (= 1×) peers G‐Yull Rhee

Countries citing papers authored by Johan U. Grobbelaar

Since Specialization

Citations

This map shows the geographic impact of Johan U. Grobbelaar's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Johan U. Grobbelaar with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Johan U. Grobbelaar more than expected).

Fields of papers citing papers by Johan U. Grobbelaar

Since Specialization

Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Johan U. Grobbelaar. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Johan U. Grobbelaar. The network helps show where Johan U. Grobbelaar may publish in the future.

Co-authorship network of co-authors of Johan U. Grobbelaar

This figure shows the co-authorship network connecting the top 25 collaborators of Johan U. Grobbelaar. A scholar is included among the top collaborators of Johan U. Grobbelaar based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Johan U. Grobbelaar. Johan U. Grobbelaar is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

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20 of 20 papers shown

Temilola, Dada Oluwaseyi, Henry A. Adeola, Johan U. Grobbelaar, & Manogari Chetty. (2023). Liquid Biopsy in Head and Neck Cancer: Its Present State and Future Role in Africa. Cells. 12(22). 2663–2663. 6 indexed citations

Schreiber, Christina, Dominik Behrendt, Gregor Huber, et al.. (2017). Growth of algal biomass in laboratory and in large-scale algal photobioreactors in the temperate climate of western Germany. Bioresource Technology. 234. 140–149. 36 indexed citations

Grobbelaar, Johan U.. (2010). Microalgal biomass production: challenges and realities. Photosynthesis Research. 106(1-2). 135–144. 146 indexed citations

Grobbelaar, Johan U.. (2008). Factors governing algal growth in photobioreactors: the “open” versus “closed” debate. Journal of Applied Phycology. 21(5). 489–492. 78 indexed citations

Zavada, Michael S. & Johan U. Grobbelaar. (2004). The earliest occurrence of Angiosperms in southern Africa. South African Journal of Botany. 70(4). 646–653. 6 indexed citations

Ripley, Brad S., et al.. (2003). Azolla filiculoides as a biofertiliser of wheat under dry-land soil conditions. South African Journal of Botany. 69(3). 295–300. 11 indexed citations

Mallick, Nirupama, Friedrich Helmuth Mohn, Carl J. Soeder, & Johan U. Grobbelaar. (2002). Ameliorative role of nitric oxide on H2O2 toxicity to a chlorophycean alga Scenedesmus obliquus.. The Journal of General and Applied Microbiology. 48(1). 1–7. 23 indexed citations

Grobbelaar, Johan U. & Friedrich Helmuth Mohn. (2002). Ozone stress in rust resistant and susceptible Helianthus annuus cultivars as measured with chlorophyll fluorescence. South African Journal of Botany. 68(4). 469–474. 3 indexed citations

Grobbelaar, Johan U., et al.. (1996). Evaluation of a short-incubation-time small-volume radiocarbon-uptake algal toxicity test. Journal of Applied Phycology. 8(1). 65–71. 9 indexed citations

10.

Grobbelaar, Johan U.. (1994). The role of turbulence and light/dark cycles on the photosynthetic rates of phytoplankton. SIL Proceedings 1922-2010. 25(4). 2242–2244. 1 indexed citations

11.

Grobbelaar, Johan U., F. Schanz, Zvy Dubinsky, et al.. (1992). Photosynthetic characteristics of five high light and low light exposed microalgaea as measured with 14C-uptake and oxygen electrode techniques. 6(1). 3–19. 4 indexed citations

12.

Grobbelaar, Johan U., et al.. (1990). Modeling algal productivity in large outdoor cultures and waste treatment systems. Biomass. 21(4). 297–314. 53 indexed citations

13.

Grobbelaar, Johan U.. (1989). The contribution of phytoplankton productivity in turbid freshwaters to their trophic status. Hydrobiologia. 173(2). 127–133. 22 indexed citations

14.

Hartig, Paul, Johan U. Grobbelaar, Carl J. Soeder, & Joost Groeneweg. (1988). On the mass culture of microalgae: Areal density as an important factor for achieving maximal productivity. Biomass. 15(4). 211–221. 32 indexed citations

15.

Grobbelaar, Johan U., et al.. (1987). Deterministic interpretation of the temperature response of microbial growth. Biotechnology and Bioengineering. 30(4). 541–547. 5 indexed citations

16.

Soeder, Carl J., et al.. (1985). Temperature Dependence of Population Growth in a Green Microalga: Thermodynamic Characteristics of Growth Intensity and the Influence of Cell Concentration. Zeitschrift für Naturforschung C. 40(3-4). 227–233. 19 indexed citations

17.

Toerien, D.F., et al.. (1985). Preliminary studies on the treatment of sorghum beer brewery effluent in an integrated bacterial/algal/fish/macrophyte culture system. Agricultural Wastes. 12(3). 207–224. 3 indexed citations

18.

Grobbelaar, Johan U. & Carl J. Soeder. (1985). Respiration losses in planktonic green algae cultivated in raceway ponds. Journal of Plankton Research. 7(4). 497–506. 85 indexed citations

19.

Soeder, Carl J., et al.. (1984). Modelling algal productivity and oxygen production in large outdoor cultures. 4 indexed citations

20.

Grobbelaar, Johan U., et al.. (1980). SOME PROPERTIES OF SUSPENDED SEDIMENT ADSORBED CATIONS IN TURBID FRESHWATERS OF SOUTH AFRICA. 6(1). 55–58. 2 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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