Hundred years of Botany at the NWU: Contributions towards understanding plant and algae function, diversity and restoration in a changing environment.

Abstract

In this paper we celebrate this milestone by giving an overview of the history of the Department at this campus, including its recent establishment and expansion on the NWU Mahikeng Campus (formerly the University of NorthWest). A brief overview is presented of the advances in teaching and research over the years, and the development and relevance of the important plant collections in the botanical garden, two herbaria and the national diatom collection. The main emphasis of this contribution is, however, a reflection on the advance ment and significance of research conducted by various disciplines on plant and algae function, diversity and ecological restoration over the years. The different disciplines in Botany at NWU, from the oldest to the more recent, are Plant Taxonomy, Plant Ecophysiology, Terrestrial Plant Ecology, Aquatic Sci ences, Urban and Settlement Ecology, Geoecology, and Proteomics. Different aspects contributing to changes occurring in the environment, such as pollution, land degradation, urbanisation, overexploitation of resources and the subsequent effect of these on plant diversity and function are especially ad dressed in our current research. The results of our research inter alia led to solu tions for problems occurring in the landscape and contribute to the wellbeing of the people using the land and water by restoring important ecosystem services.

Full text

BOTHALIA – African Biodiversity & Conservation
ISSN: (Online) 2311-9284, (Print) 0006-8241
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Page 1 of 15
The Department of Botany on the Potchefstroom Campus (formerly Potchef-
stroom University for Christian Higher Education) of the North-West University
(NWU) had its centenary in 2020.
In this paper we celebrate this milestone by giving an overview of the history of
the Department at this campus, including its recent establishment and expansion
on the NWU Mahikeng Campus (formerly the University of North-West). A brief
overview is presented of the advances in teaching and research over the years,
and the development and relevance of the important plant collections in the
botanical garden, two herbaria and the national diatom collection.
The main emphasis of this contribution is, however, a reflection on the advance-
ment and significance of research conducted by various disciplines on plant and
algae function, diversity and ecological restoration over the years.
The different disciplines in Botany at NWU, from the oldest to the more recent,
are Plant Taxonomy, Plant Ecophysiology, Terrestrial Plant Ecology, Aquatic Sci-
ences, Urban and Settlement Ecology, Geoecology, and Proteomics.
Different aspects contributing to changes occurring in the environment, such
as pollution, land degradation, urbanisation, overexploitation of resources and
the subsequent effect of these on plant diversity and function are especially ad-
dressed in our current research. The results of our research inter alia led to solu-
tions for problems occurring in the landscape and contribute to the well-being of
the people using the land and water by restoring important ecosystem services.
Keywords: Aquatic sciences, geoecology, plant ecophysiology, proteomics, tax-
onomy, terrestrial plant ecology, urban and settlement ecology.
Introduction
The Botany Department of the former Potchefstroom University for Christian
Higher Education (PU for CHE) (now part of the North-West University) was
100 years old in 2020. To celebrate this milestone this special issue of Bothalia
– African Biodiversity and Conservation was initiated. The aim of the present
paper is to provide an overview of the 100-year history of the Botany Depart-
ment and the botanical garden at this institution, and also to highlight research
in the different disciplines and their contribution towards knowledge on plant
and algae function, diversity and ecology. Most of the current research has
focused on addressing the negative effects associated with land-use changes.
As this is not intended to be a complete review of each research discipline,
Authors
1S.S. Cilliers
1S. Janse van Vuuren
1K. Kellner
1G.H.J. Krüger
1M. Struwig
2C.J.G van Niekerk
1S.J. Siebert
Aliations
1Unit for Environmental Sciences
and Management, North-West
University, Private Bag X6001,
Potchefstroom 2520, South
Africa.
2NWU Botanical Garden, North-West
University, Private Bag X6001,
Potchefstroom 2520.
Corresponding Author
Prof. Sarel S. Cilliers
Sarel.Cilliers@nwu.ac.za
Dates
Accepted: 13 October 2020
Published: 24 February 2021
How to cite this article:
Cilliers, S.S., Janse van Vuuren,
S., Kellner, K., Krüger, G.H.J.,
Struwig, M., Van Niekerk,
C.J.G. & Siebert, S.J., 2021,
‘Hundred years of Botany
at the NWU: contributions
towards understanding plant
and algae function, diversity
and restoration in a changing
environment’, Bothalia 51(1), a2.
http://dx.doi.org/10.38201/btha.
abc.v51.i1.2
Hundred years of Botany at the NWU:
contributions towards understanding plant and
algae function, diversity and restoration in a
changing environment

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Page 2 of 15
only few of the most important research papers are
highlighted. The other contributions in this special issue
will focus on specific current research projects in the
Department.
Brief History of
the Department of
Botany at NWU
A century ago it was not unusual to find Botany stu-
dents attending lectures in an old stable in Potchefst-
room (Figure 1) on the premises of the house of Marthi-
nus Wessel Pretorius, former president of the South
African Republic/Zuid-Afrikaansche Republiek (in the
1880s). This is where Botany found its humble begin-
nings in the earlier years of the PU for CHE. On sunny
days, practical classes were conducted under the oak
trees (Quercus robur L.) in the garden, which are still to-
day silent witnesses of those earlier ‘aha!’ experiences
so typical of studies of the plant kingdom. Botany later
moved to the more luxurious, old prefabricated mili-
tary barracks that were erected on the main university
campus in Potchefstroom (Jooste 2017). Subsequently,
Botany has since relocated twice, and today has excel-
lent facilities including laboratories, a botanical garden,
herbaria, ecological research sites, green houses and
open-top growth chambers, all state of the art.
Initially, in 1920, Botany and Zoology courses were
presented by one lecturer, but five years later a ded-
icated lecturer for Botany, Mildred Radloff (Figure 2),
was appointed. She had to carry a full load of lecturing
and presenting practical classes for all three pre-gradu-
ate year groups until 1931 when she married and had
to resign due to the protocol of the University at that
time. The first professor and head of department was
Antonie Goossens (Figure 3) and with his appointment
(1932–1961) a new phase started for Botany, with the
first master’s degree student (Mr W.J. Stapelberg) en-
rolling in 1933. Goossens was dedicated to develop
Afrikaans terminology for Botany and he and a col-
league, Piet Botha, published the first comprehensive
Botany textbook in Afrikaans, Leerboek vir Plantkunde,
in 1944, which was used at all the Afrikaans universi-
ties until 1971. He also published the first Afrikaans key
to the families and genera of flowering plants of South
Africa (1940), and compiled the first English–Afrikaans/
Afrikaans–English botanical dictionary (1972).
Botha became the next head of department (1962–
1972). He specialised in plant physiology under guid-
ance of the renowned plant physiologist Prof Karl Wet-
zel of the Friedrich Wilhelm University, but due to the
outbreak of World War II in 1939, he had to flee Ger-
many. He completed his doctorate through the Univer-
sity of South Africa (UNISA). Another botanist at the PU
for CHE who was affected by the war was Max Papen-
dorf (later the third head of department; 1973–1982).
He had earlier completed an excellent master’s study
under Goossens. Papendorf had received the George
Grey bursary to study abroad but was prevented by the
outbreak of the Second World War (Jooste 2017).
Daan Botha was appointed as the fourth head of de-
partment (1983–1985) and he will be remembered for
his initiative to change the veld garden into a botanical
Figure 1. First lecture room for Bot-
any – a stable (Source: NWU Re-
cords, Archives and Museum).

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garden, which is now a living legacy. Botha left in 1985
and became the Director of the National Botanical
Gardens of the National Botanical Institute (later South
African National Biodiversity Institute). His successor,
Ockie Bosch (1986–1993), focused on establishing an
integrated approach in the teaching of Botany, which
culminated in significant changes to the curricula and
a name change from the Department of Botany to the
Department of Plant Sciences, in accordance to in-
ternational trends at the time. Five years later anoth-
er name change followed when Soil Sciences merged
with Plant Sciences to become the Department of Plant
and Soil Sciences. This led to further changes in the
curricula to ensure that plant and soil sciences comple-
mented each other at honours level so that postgradu-
ate students could specialise in resource development,
horticultural sciences, pasture ecology or plant pathol-
ogy. When Braam Pieterse became the sixth head of
department (1994–1997), the integrated approach was
phased out, and eventually he reinstated the Botany
Department with focus on the sub-disciplines of Botany
(Jooste 2017).
In 1996 the University embarked on the formation of
different Schools and Botany became one of six sub-
ject groups in the School of Environmental Sciences
and Development. No major changes occurred in the
undergraduate courses, but at postgraduate level the
focus was placed on Environmental Sciences and bota-
ny lecturers contributed to integrated courses in differ-
ent streams, namely Ecological Remediation and Sus-
tainable Management, Biodiversity and Conservation
Biology and Water Sciences. Since 1998, the subject
group Botany was led by chairs on a rotational basis
(Gert Krüger (1998–2002), Sarel Cilliers (2003–2006
and 2009–2013), Klaus Kellner (2007–2008), Sanet
Janse Van Vuuren (2014–2016), Stefan Siebert (2017–
2019) and currently Sandra Barnard (2020–). In 2004
the PU for CHE merged with the former University of
North-West and the Sebokeng campus of the Vista Uni-
versity to form the North-West University with three
campuses (Potchefstroom, Mahikeng and Vanderbijl-
park) and eight faculties.
In 2012 the School of Environmental Sciences and De-
velopment split into two new Schools and Botany be-
came part of the School of Biological Sciences (Jooste
2017). Postgraduate studies were divided into different
subprogrammes and Botany staff and students contrib-
ute to Aquatic Ecosystem Health, Biodiversity and Con-
servation Ecology as well as Ecological Interactions and
Ecosystem Resilience (Jooste 2017). In 2017 the Botany
subject group expanded to the Mahikeng campus. Sub-
sequently, major changes in the undergraduate courses
had to be implemented to align the Botany modules
between campuses.
Figure 2. Miss Millie Radloff, first lecturer in Botany (Source:
NWU Records, Archives and Museum).
Figure 3. Prof. A.P Goossens, first Professor and Head of De-
partment of Botany (Source: NWU Records, Archives and
Museum).

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Although Botany curricula have been changed quite
drastically over the years there was always a constant
stream of students interested in Botany. Enrolled stu-
dent numbers averaged 113, 61 and 37 for Botany I,
II and III respectively since 2010. Botany has also been
phased in successfully on the Mahikeng campus and
in 2020 we have enrolled 123, 56 and 55 students for
Botany I, II and III respectively. Post-graduate training
has always been an important focus for the Botany De-
partment. Over the last ten years, 105 Masters and 25
PhD students were supervised in different disciplines of
Botany at the NWU.
Both past and current alumni are well known names in
the South African Botany community. The list is long and
here we list only those with postgraduate degrees from
the department who became professors at other univer-
sities – Manie van der Schijff, Albert Eicker, Braam van
Wyk (all Pretoria), Kobus Eloff, Braam Pieterse, Amie van
der Westhuizen (all Free State), Jan de Bruin, Johan Visser,
Frikkie Botha, Anna-Maria Botha (all Stellenbosch), and
Ockie Bosch (University of Queensland, Australia) (Jooste
2017). Botany alumni are also employed outside aca-
demia in various sectors (often in senior positions) – Agri-
cultural Research Council, Department of Environment,
Forestry and Fisheries, Eskom, MidVaal Water Company,
North-West Province Agriculture, Rand Water, South
African Environmental Observation Network, South Af-
rican National Biodiversity Institute, South African Sugar
Research Institute, and various botanical gardens, private
environmental consultation firms and NGOs.
Brief History of the NWU
Botanical Garden
The origins of the NWU Botanical Garden (Figure 4)
may be traced back to 1925, when Radloff was ap-
pointed as the first Botany lecturer at the Potchef stroom
University. She was responsible for the collection of
fresh plant material for practical sessions, and the Bo-
tanical Garden would eventually grow due to this need
for plant material – and it remains one of the key func-
tions of the garden to this day.
However, it was several decades later, in the early
1960s, that the first steps were taken by Goossens to ini-
tiate a garden. At the insistence of Goossens, Wynand
Louw was appointed in 1962 as a taxonomist and Bot-
any lecturer, and one of his first tasks was to develop
Figure 4. Botanical Garden – Waterfall on Prof. Daan Botha’s koppie. (Photo: Chris van Niekerk from NWU Botanical Garden collection).

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a garden to grow plant material for practical classes.
Louw identified a piece of land in the northern part
of the campus and started to develop a veld garden to
supply fresh plant material over the next eight years,
until 1970, when he left the university.
The idea to develop a proper botanical garden came
in 1971, with the appointment of Daan Botha as plant
taxonomy lecturer and curator of the herbarium (Table
1). In 1972 he appointed the garden’s first horticulturist,
Derick Pitt, to help with the development and mainte-
nance of the garden. Pitt left the garden within a year
after his appointment and Bert Ubbink, a horticulturist
from the University of Pretoria, was appointed as the first
permanent curator of the garden in 1973. Ubbink was
responsible for the design, layout and construction of the
pathways and the water ponds throughout the garden.
During the early 1990s, the University drastically re-
duced funding of the Botanical Garden and there was a
shift in focus to more integrated teaching and research.
The maintenance of the Botanical Garden was trans-
ferred to the campus garden services and the Garden
curator was redeployed to the Technical Services De-
partment on campus. This was the start of a period of
tragic neglect of the Garden. Over the next decade, the
Garden and buildings deteriorated to a state of dilapi-
dation and an overgrown piece of veld.
The recovery and revival of the Botanical Garden start-
ed in 2003 with the appointment of a new curator,
Peter Mortimer. Under the leadership of Mortimer, the
deteriorated structures were repaired, unwanted trees
were removed, and new flower beds were designed
and constructed.
After the aforementioned merger of universities in
2004, Annette Combrink, rector of the Potchefstroom
campus, recognised the important role of the Botani-
cal Garden for community education, capacity build-
ing, and for promoting the image of the NWU. Mar-
tin Smit succeeded Mortimer as the Garden curator
(2007–2011), and he sourced funds through Combrink
to further improve the Botanical Garden. Smit and his
team made huge improvements to the garden design
and layout (Smit et al. 2011). The current curator of
the Garden, Chris van Niekerk, was appointed on 1
November 2011, and is implementing Smit’s vision to
expand the plant collections and to make the Botanical
Garden a multi-disciplinary experience. To achieve this
the garden added a geological display in a geological
rock garden representing a walk back in time through
rocks exposed in the 2023 million year old Vredefort
meteorite impact structure and a site-specific digital lit-
erature experience called ‘Byderhand’.
The living plant collection in the Garden represents spe-
cies from 105 families. Rare species such as Brachystel-
ma barberae Harv. ex Hook.f., Clivia mirabilis Rourke,
Prototulbaghia siebertii Vosa, Searsia batophylla (Codd)
Moffett and Welwitschia mirabilis Hook.f., serve as
reference collections for research projects (Berner et
Table 1. Founders and curators of the plant collections of the Potchefstroom and Mahikeng campuses of the North-West University since
1932
Curator Period Years Collection
Antonie P. GoossensF1932–1961 29 Herbarium of the PU for CHE (PUC)
Wynand J. Louw 1962–1970 8 PU for CHE Veld Garden
Daniel J. BothaG1971–1985 14 Herbarium of the PU for CHE (PUC)
Bert Ubbink 1973–1990 17 PU for CHE Botanical Garden
Sello D. PhalatseF1983–2008 25 University of North-West Herbarium (UNWH)
Gideon F. Smith 1986–1992 6 Herbarium of the PU for CHE (PUC)
Daniël J. Theunissen 1993–1997 4 Herbarium of the PU for CHE (PUC)
Matthias H. BuysB1998–2006 8 A.P. Goossens Herbarium (PUC)
Peter Mortimer 2003–2006 3 North-West University Botanical Garden
Stefan J. Siebert 2007–present 14 A.P. Goossens Herbarium (PUC)
Martin F. Smit 2007–2011 4 North-West University Botanical Garden
Jonathan C. TaylorB2009–present 11 South African National Diatom Collection (SANDC)
Pieter W. Malan 2009–2016 7 University of North-West Herbarium (UNWH)
Christiaan J.G. van Niekerk 2012–present 9 North-West University Botanical Garden
Madeleen StruwigB2017–present 4 S.D. Phalatse Herbarium (UNWH)
FFounder, BRenamed collection, GFounder of the botanical garden

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al., 2020). The Garden not only supports training and
research of students within the NWU, but it also fo-
cusses on ex situ conservation of various species. More
than 2000 individuals of the endemic Khadia beswickii
(L.Bolus) N.E.Br. (Van Niekerk & Siebert 2018) and var-
ious other species of special interest, such as Boophone
disticha (L.f.) Herb. and Nananthus vittatus (N.E.Br.)
Schwantes, have been rescued, relocated and moni-
tored due to destruction of their natural habitat.
Different Research
Disciplines in Botany
Plant taxonomy
Plant taxonomic research at the Potchefstroom campus
dates back to the early 1930s. The first taxonomic work
was conducted by Antonie Goossens (Figure 2) who fo-
cussed on grasses from the Potchefstroom region. This
eventually led to the description of the genus Bewsia
Gooss. (Goossens 1941) and several grass species new
to science, for example Anthephora argentea Gooss.,
Enneapogon spathaceus Gooss., Sporobolus bechuani-
cus Gooss., Styppeiochloa gynoglossa (Gooss.) De Win-
ter, Tarigidia aequiglumis (Gooss.) Stent and Urochloa
stolonifera (Gooss.) Chippind. (Goossens & Philips
1932). The Herbarium of the PU for CHE was founded
by Goossens in 1932. The herbarium was later renamed
in his honour by the sixth curator, Matt Buys (Table 1),
and officially became the A.P. Goossens Herbarium. To-
day it holds over 30 000 specimens for educational and
research purposes.
In the 1960s, Wynand Louw succeeded Goossens as
taxonomist and discovered many new species of succu-
lents, of which Euphorbia louwii L.C.Leach commemo-
rates his life-long dedication. From 1970 to mid-1980s,
Daan Botha was the resident plant taxonomist and
under his supervision various taxonomic studies were
conducted on a range of genera, such as Antizoma
(Menispermaceae), Brachylaena (Asteraceae), Crabbea
(Acanthaceae), Eugenia (Myrtaceae), Sphedamnocar-
pus (Malphigiaceae) and Vitex (Lamiaceae). Various
taxonomic changes were proposed (e.g. Bredenkamp
& Botha 1993). Gideon Smith succeeded Botha in
1986, and like Louw, was a succulent devotee with a
research interest in the Asphodelaceae, Crassulaceae
and Mesembryanthemaceae (now Aizoaceae), which
subsequently led to the revision of several genera in
later years. Both Botha and Smith moved on to head
up directorates at the National Botanical Institute (later
South African National Biodiversity Institute).
During this period the University of North-West her-
barium (UNWH) was established in Mahikeng by Da-
vid Phalatse (Figure 5). He established the herbarium
in 1983 as a teaching facility for the Biology Depart-
ment at the then University of Bophuthatswana. This
herbarium became part of the University of North-West
and later the North-West University during the amal-
gamation in 2004. With the introduction of Botany as
subject on the Mahikeng campus in 2017, it was in-
corporated into the subject group of Botany and was
renamed the S.D. Phalatse Herbarium by the third cu-
rator, Madeleen Struwig (Table 1). The collection is fast
approaching 1 000 specimens and will be expanded
considerably to meet the educational and research de-
mands of the Mahikeng campus. Like the A.P. Goossens
Herbarium, it also serves as a voucher repository for
various disciplines studying plants, their products and
applications beyond pure botanical studies.
In the mid-1990s, Danie Theunissen combined his
ecological and taxonomical knowledge to identify grass
ecotypes for application in agriculture and rehabili-
tation, which culminated in a range of ecosystematic
accounts of ecotypes in grass genera such as Digitar-
ia, Eragrostis, Setaria and Themeda (Theunissen 1992).
Matt Buys was taxonomist from 1998 to 2006 and had
a keen interest in the genera Lobostemon (Boragina-
ceae), for which he described various new taxa, and
the phylogeny of Delosperma (Aizoaceae). Under his
supervision the genera Drimiopsis (Hyacinthaceae)
(Lebatha et al. 2006), and Ruschia (Aizoaceae) were
revised. He is currently the curator of Scion’s National
Forestry Herbarium in New Zealand.
Figure 5: Mr Sello D. Phalatse, first Botanist at Mahikeng Cam-
pus (1983–2008), founder and curator of the University of
North-West Herbarium (Source: NWU Records, Archives and
Museum) (Source: NWU Corporate Relations and Marketing).

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Since 2007 taxonomic work has mainly focussed on
Boerhavia and Commicarpus in the Nyctaginaceae
(Struwig & Siebert 2013). The two genera were revised
for the first time in southern Africa and resulted in the
description of a new species, B. orbicularifolia Struwig,
and a new variety, C. squarrosus (Heimerl) Standl. var.
fruticosus (Pohn.) Struwig (Struwig & Siebert 2013).
Floristic studies have also led to the description of rare
and endemic species from Sekhukhuneland in Limpo-
po (Siebert et al. 2010), such as Euclea sekhukhuniensis
Retief, S.J.Siebert & A.E.van Wyk (Ebenaceae), Pavetta
glaucophylla Retief, S.J.Siebert & A.E.van Wyk (Rubia-
ceae), and Polygala sekhukhuniensis Retief, S.J.Siebert
& A.E.van Wyk (Polygalaceae). With the advent and
development of Botany as a subject on the Mahikeng
campus in 2017, taxonomic research has gained mo-
mentum under Struwig and various revisions are cur-
rently underway on members of the Molluginaceae.
To strengthen taxonomic research at the NWU, two
extraordinary lecturing appointments were made of
taxonomists employed by the South African Nation-
al Biodiversity Institute. Pieter Bester was appointed
to the Potchefstroom Campus from 2013 and Marin-
da Koekemoer to the Mahikeng Campus from 2019.
Bester is an expert on the Apocynaceae and Koeke-
moer on the Asteraceae. Their knowledge of the diag-
nostic characters of plant families, and development of
educational material for use in practical plant identifi-
cation have greatly contributed to the training of un-
dergraduate students studying the flora of South Africa.
Taxonomy at NWU has contributed to the national
effort to categorise and name plants. The major focus
has been on the Poaceae, and specialist interest in the
Apocynaceae and Nyctaginaceae (Bester & Nicholas
2018, Struwig & Siebert 2013). The specific focus on
grasses in both herbaria has enabled other botanical
fields studying land-use change in the Grassland and
Savanna biomes to identify and measure character
traits of the fundamental units of biodiversity, name-
ly the species. The A.P. Goossens Herbarium holds an
actively utilised, ornamental plant collection of close
to 2 500 specimens originating from an urbanisation
gradient stretching from rural villages to the Johannes-
burg metropole. It also keeps large ecological voucher
collections (> 20 000 specimens) of the Potchefstroom
region to Vredefort Dome (both the Dry and Mesic
Highveld Grassland Bioregions), Ganyesa to Griqua-
land-West (Eastern Kalahari Bushveld Bioregion), and
Dwarsberg to Impala Platinum (Central Bushveld Biore-
gion). In recent years, taxonomists on both campuses
have contributed to new research in Botany that focus-
es on the taxonomical and functional trait diversity of
forbs across land-uses in grassy biomes (Siebert et al.
2021). To support this initiative, a large collection of
forbs from the Lowveld Bioregion has been collected
over a decade.
Plant ecophysiology
Piet Botha established the plant physiology discipline
in 1937. The theme of Botha’s PhD degree from the
University of South Africa was the biology of the plant
parasite Alectra vogelii Benth. (Botha 1950). He was
the director of the Institute for Plant Physiological Re-
search at PU for CHE, which was established in 1949,
and which later became the Institute for Botanical Re-
search in 1970. Charles Whitehead (appointed as lec-
turer/associate professor in 1977) investigated ethylene
sensitivity in plant tissues to elucidate the mechanisms
involved in the control of senescence and ripening in
plants with the view to develop effective methods to
delay senescence and ripening of fruits and vegetables
(Whitehead et al. 1984).
Since the appointment of Gert Krüger in 1988, the focus
of research in plant physiology was directed at studying
the physiological and biochemical basis of the response
of crop plants and natural vegetation to environmen-
tal stress. The research, with an integrative approach,
involved studying plant responses on a reductionist
as well as on a whole-plant level, ideally suited to the
teaching of the principles of plant physiology. The key
feature facilitating research on plant responses was the
outstanding laboratories for the study of the ecophysi-
ology and biochemistry of photosynthesis, and facilities
to grow plants under strictly controlled conditions, such
as a state-of-the-art open-top chamber facility (OTC)
(Figure 6) for studying air pollution effects.
In an endeavor to determine the physiological param-
eters that could be used as drought tolerance selec-
tion criteria for different tobacco cultivars, the effect
of induced drought was studied in depth through its
effect on photosynthetic gas exchange (Van Rensburg
& Krüger 1993a), oxidative stress metabolism, accumu-
lation of secondary metabolites such as proline and ab-
scisic acid (Van Rensburg & Krüger 1993b) and osmo-
regulation, by postgraduate student and later Research
Director: Unit for Environmental Sciences and Man-
agement, NWU, Leon van Rensburg. During this time
supportive research on the anatomical and cytological
anomalies found in studies of water stress on plants was
done by Hester Kruger.
Pioneering studies on the application of prompt chloro-
phyll a fluorescence induction for assessing photosyn-
thetic potential and vitality of test plants subjected to
environmental stress were undertaken in close collab-
oration with the international expert on chlorophyll a
fluorescence kinetics, Reto Strasser, University of Ge-
neva. By analysing fluorescence transients of plants
exposed to different light regimes according to the
so-called JIP-test, deconvoluting the behavior of PSII
into several functional and structural parameters, it was
demonstrated that these parameters undergo differen-
tial changes upon a particular stress. The JIP-test is now

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used all over the world and the paper by Botany staff is
regarded as a standard document (Krüger et al. 1997).
Further technical developments of the JIP-test were il-
lustrated by several papers on chilling stress in soybean.
Riekert van Heerden joined the department as plant
physiologist in the mid-1990s and his doctoral stud-
ies on various aspects of chilling stress in soybean
culminated in several key publications. With the aim
to identify the traits that convey dark chill stress toler-
ance various approaches were employed, such as de-
termining the effect of separately and simultaneously
induced dark chilling and drought stress on photosyn-
thesis, the monitoring in parallel of CO2-assimilation,
O-J-I-P chlorophyll fluorescence kinetics and nitrogen
fixation of test plants, and assessing the constraints on
Calvin-Benson cycle metabolism (Van Heerden et al.
2003). An outstanding practical outcome of the chilling
stress research was the ranking of chilling tolerance in
soybean genotypes probed by the O-J-I-P chlorophyll
fluorescence transient (Strauss et al. 2006).
During the period 2002–2008 several investigations
on the effect of air pollution on natural vegetation and
crop plants were undertaken. This work was initially
done in collaboration with the Helmholz Environmen-
tal Research Centre, Leipzig-Halle, Germany and the
Atmospheric Chemistry Research Group of the North-
West University. Various publications appeared on sub-
jects such as the constraints on photosynthesis of C3 and
C4 crop plants by trichloroacetic acid and the effect of
fluorinated hydrocarbons on C3 and C4 crop plants (Smit
et al. 2008). Studies using OTCs included the physiology
of SO2 injury and the interaction thereof with drought
stress in soybean, comprising the measuring of effects
on photosystem II structure and function, photosynthetic
gas exchange, Rubisco activity, water relations and nitro-
gen fixation (Heyneke et al. 2012). The constraints im-
posed by elevated levels of tropospheric ozone on crop
plants were also studied employing the OTC system. Be-
ing able to, in addition, regulate the CO2 concentration
of the air in the OTCs allowed assessment of the effect
of elevated atmospheric CO2 concentrations to obtain
insight into the effects of increased atmospheric CO2 lev-
els associated with global warming (Maliba et al. 2019).
Jacques Berner joined Botany as plant physiologist in
2007. Currently, the research of Berner is directed to-
wards the acclimation strategies of new climate resilient
crops, like quinoa and amaranth. Prompt fluorescence
and modulated 820 nm reflection are extensively used
to evaluate biotypes with stress tolerance. His skills for
the study of the ecophysiology of plants in vivo and
in situ, were also successfully applied in studies on
Figure 6. State-of-the-art open top chambers for research in ecophysiology (Photo: Jacques Berner).

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environmental stress exerted on plants of the Namib
Desert (Krüger et al. 2017; Berner et al. 2021).
Terrestrial plant ecology
Ecological studies began in 1963 after Koos van Wyk
completed his PhD and started with research on deg-
radation of pastures. In 1979 he founded the Institute
for Ecological Research with external funding that fo-
cused initially on the rehabilitation of road verges, but
later also on mine tailings. This institute went through
a number of name changes and was terminated under
the name Research Institute for Rehabilitation Ecology
(Eco-Rehab) in 2005. From 1982 to 1988, George Bre-
denkamp did extensive phytosociological research on
grasslands and savannas and several papers were pub-
lished from this research (e.g. Bredenkamp et al. 1989;
Bredenkamp & Bezuidenhout 1990).
After the appointment of Ockie Bosch as the head of
the Department in 1986, the focus was to develop an
integrated approach so that all the disciplines in Bota-
ny functioned as a unit to encourage collaboration be-
tween all scientists in studying community ecology in a
dynamic environment.
Johan Booysen, a computer modeler and systems ecol-
ogist, joined the Department in 1990. He integrated
the community ecology thinking of Bosch into a user
friendly computer program to study how the changes
in the environment due to climate and management
impacts lead to land degradation. This program was
named the Integrated System for Plant Dynamics,
which required inputs from all sections of Botany, but
especially the plant and agricultural ecologists (Kellner
& Booysen 2000).
The models of Bosch focused on the influence that
management practices have on natural and agricultural
ecosystems. To promote sustainable land management,
the research focus was on systems ecology, and in col-
laboration with EcoRehab, it became possible to also
address the restoration of degraded rangelands.
Klaus Kellner was appointed at the PU for CHE in 1988
to carry out research on land degradation and rehabil-
itation ecology in arid- and semi-arid regions of South
Africa. He also represented South Africa as the Science
and Technology Correspondent (STC) in the Commit-
tee for Science and Technology, a subsidiary body of
the United Nations Convention to Combat Desertifica-
tion (UNCCD), served as president of the STC and rep-
resented the African continent at the UNCCD. He was
also appointed by the UNCCD to global committees
regarding the study of the impacts and control of De-
sertification, Land Degradation and Drought (DLDD),
as well as what technologies can be implemented to re-
store/rehabilitate these lands. This included the ad hoc
Working Group on Scientific Advice (AGSA), which was
formed to identify strategies to bridge the gap between
rangeland scientists and policy makers working in the
environment (Akhtar-Schuster et al. 2016). DLDD re-
search in terrestrial ecology excelled at NWU and
many post-graduate studies and projects followed for
government departments in South Africa. International
collaboration with organisations from Germany, Na-
mibia, Spain and other European Union countries fol-
lowed, regarding rangeland restoration after the control
of woody shrub encroachment (bush encroachment) in
arid- and semi-arid rangelands (Harmse et al. 2016).
Although the initial projects were broad, they soon fo-
cused more on the western parts of South Africa, as well
as the southern parts of Namibia and Botswana (Kell-
ner et al. 2018). Pieter Malan of the Mahikeng campus
collaborated with expertise in bush encroachment and
restoration after the control of woody invasive species.
Research on land degradation and restoration ecolo-
gy was extended to include aspects of climate change
and the socio-economics of the land users applying sus-
tainable land management, especially in the Kalahari
region (Kellner & Bosch 2003). One of the main aims
of the UNCCD is to develop a land degradation neu-
tral world, which means that the land that is prone to
desertification should be restored after detailed mon-
itoring of the parameters causing the degradation or
desertification (Von Maltitz et al. 2019).
Research on grassland and savanna ecosystem dynam-
ics and resilience was expanded from 2012, when Fran-
ces Siebert joined Botany. Her relationships with South
African National Parks and the Ndlovu (i.e. savanna)
node of the South African Environmental Observation
Network supported long-term vegetation monitoring
in Lowveld savanna. These projects led her to identify
the need for an improved understanding of the ecolo-
gy of forbs, a neglected plant life-form in savanna and
grassland (Siebert & Dreber 2019), as they are often
perceived as weeds and indicators of land degradation.
Forbs, however, provide important forage stability to
a wide array of herbivores (Siebert & Scogings 2015).
This research has put her on the forefront of interna-
tional networks working on this topic. She has initiat-
ed a forb ecology research consortium with research
partners from Brazil, Germany, the Netherlands and
national associates, which has led to inclusion in other
international working groups, such as the Tropical and
Sub-tropical Savanna Plant Functional Traits working
group, the International Grassland Restoration working
group and the Grazing Exclosure Consortium.
Aquatic Sciences
Aquatic research in Botany includes algal diversity in
relation to water quality parameters, including inorgan-
ic and organic pollutants. This research focus was es-
tablished at the former PU for CHE by Braam Pieterse

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in 1994. At that stage the aquatic research team con-
sisted of Pieterse and four postgraduate students,
namely Sanet Janse van Vuuren, Antoinette Vermeulen,
Annelie Swanepoel and Danie Traut. Initially, aquatic
research primarily focused on the diversity of algae and
environmental variables influencing their growth and
succession in the Vaal River system (Janse van Vuuren &
Pieterse 2005). Over time, especially with the appoint-
ment of aquatic scientists from other institutions, the re-
search expanded to include other river systems, dams,
and various other habitats throughout the country, and
also other research subjects within aquatic sciences.
During 1995, Janse van Vuuren was appointed as ju-
nior lecturer in the Department of Botany. Although her
early-career research focused primarily on the taxono-
my, diversity and ecology of phytoplankton in various
freshwater systems throughout the country, she was
later also involved in studies of algae in water purifica-
tion plants, the development of harmful algal blooms
(HABs) and aerophytic algae growing against cave walls.
Her research culminated in a book on the identification
of common freshwater algae (Janse van Vuuren et al.
2006), as well as two chapters in a book on freshwater
life (Griffiths et al. 2015).
Sandra Barnard joined the water research group as
a lecturer in the Department of Botany in 1996. She
initiated a physiological and molecular biological fo-
cus in the existing research on algae and this approach
later formed an integrated part of aquatic research at
the NWU (Conradie & Barnard 2012). Barnard also
published research papers about water quality and
pioneered research to predict the dynamics and po-
tential of HABs (Van Ginkel et al. 2007; Swanepoel et
al. 2016). International cooperation, including a suc-
cessful student exchange programme, was established
between South Africa and Finland (2002–2005).
During 2000, Arthurita Venter completed her PhD on
Oscillatoria simplicissima Gomont – a potentially toxic
cyanobacterium that often forms blooms in South Afri-
can freshwaters. She was later appointed as an admin-
istrative officer in Botany and continued to author sev-
eral papers on the diversity of algae and cyanobacteria
not only in aquatic, but also terrestrial environments
(Venter et al. 2013). She is currently considered as a
pioneer in understanding the biodiversity of biologi-
cal soil crusts found on serpentine and mine tailings in
South Africa (Venter et al. 2018).
Jonathan Taylor became interested in algae when he
first studied these organisms during his first year Botany
lectures at the PU for CHE in 1997. His interest eventu-
ally led to postgraduate studies in Phycology (the study
of algae), during which he became interested in a par-
ticular group of algae, the diatoms, which are excellent
bio-indicators of environmental conditions. As part of
his PhD thesis he tested the application of diatom-based
pollution indices, developed for northern hemisphere
conditions, in southern hemisphere waters. This led to
several publications about the application of diatoms
as water quality indicators in South Africa (e.g. Taylor
et al., 2007). Today Taylor is known for his work on the
taxonomy and ecology of the diatoms from central and
southern Africa. He described or contributed to the de-
scription of three new diatom genera, 19 new diatom
species and three new red algal species. In addition,
several diatom species have been named in his hon-
our, namely Luticola taylorii Levkov, Metzeltin & Pav-
lov, Nitzschia taylorii Alakananda, Hamilton & Karthick,
and Muelleria taylorii Van de Vijver & Cocquyt.
Taylor is also curator of the South African National Di-
atom Collection (SANDC) (Table 1) that was started in
1950 by Béla Cholnoky from the University of Preto-
ria, later from the Council of Scientific and Industrial
Research (CSIR). Other well-known phycologists who
contributed to the diatom collection were Robert (‘Ar-
chie’) Archibald, Ferdinand Schoeman (both students
of Cholnoky) and Malcolm Giffen (University of Fort
Hare). Over the years the national collection also re-
ceived donations from many scientists abroad and thus
contains not only South African material but a large se-
lection of material from around the world. The CSIR
donated the collection to the South African Institute for
Aquatic Biodiversity (SAIAB) in 2009 to ensure its long
term preservation. SAIAB, in turn, has loaned the col-
lection to the NWU in an open-ended agreement (Tay-
lor et al. 2011) as the NWU was becoming a centre for
diatom studies (especially taxonomy) in the mid-2000s.
The collection, now lodged in the Botany department,
has since its move been actively digitised, further cat-
alogued and the type material of many South African
species has been investigated. The SANDC is now also
a registered herbarium.
Anatoliy Levanets, originally from the Ukraine, joined
the research team as a postdoctoral fellow from 2003 to
2006. His experience and knowledge about the diversi-
ty of soil and other terrestrial algae complimented exist-
ing research on aquatic algae, and it led to several stud-
ies on the role that soil algae fulfill in the rehabilitation
of mine dumps. The effect of various land-uses, such
as effluents of mines containing high metal concentra-
tions, directly influences the morphology and diversity
of algal species and therefore research on this subject
is extremely important. As part of their studies Levanets
and Taylor described three new terrestrial diatom spe-
cies (Microcostatus schoemanii Taylor, Levanets, Blanco
& Ector, M. cholnokyi Taylor, Levanets, Blanco & Ector
and M. angloensis Taylor, Levanets, Blanco & Ector) from
South Africa (Taylor et al. 2010). In addition to his in-
terest in terrestrial algae, Levanets is also interested in a
particular group of freshwater green algae (desmids) and
he published an annotated and illustrated list of desmids
of southern Africa (Levanets & Van Rensburg 2011).
Information presented in the previous paragraphs illus-
trates the wide scope of freshwater and algal related

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research within the subject group Botany. Freshwater
research at many other universities is limited, as most
are situated in coastal areas and focus more on marine
algae and marine research.
Urban and settlement ecology
This research discipline was initiated in 1998 with
the completion of the PhD thesis of Sarel Cilliers on
the phytosociology of the city of Potchefstroom under
the supervision of George Bredenkamp. This was the
first-ever study on the description of plant communities
in different land-use areas in an urban setting in South
Africa. At that time no other ecologist at any African
university was interested in the ecology of urban open
spaces. Publications from this thesis described plant
communities in land-use areas such as vacant lots, in-
tensively managed areas, railway reserves, natural and
semi-natural grasslands and woodlands, wetlands and
roadside verges. The paper on roadside verges (Cilliers
& Bredenkamp 2000) was the most influential publica-
tion of all of them. These studies also formed the basis
for mapping urban biotopes (habitats) in Potchefstroom
to provide ecological data for conservation-orientated
planning and management of urban open spaces (Cil-
liers et al. 2004). Moreover, the Tlokwe City Council
used these biotope maps in the development of the
spatial development framework of the city.
This initial start led to a focus on the investigation of
plant diversity patterns and processes in small and me-
dium-sized cities. Two clear directions were followed,
namely fragmented natural grasslands along an urbanisa-
tion gradient using a landscape ecological approach, and
home and community gardens along socio-economic
gradients. Firstly, a Master’s degree student, Marié du Toit
refined a methodology developed in Melbourne, Austra-
lia to quantify the urbanisation gradient in Klerksdorp (Du
Toit & Cilliers 2011). This approach was widely used in
other studies at the NWU and also globally. Du Toit later
completed a PhD and is currently a postdoctoral fellow at
the NWU. Important findings from the fragmented grass-
lands research have indicated that urban grasslands are as
important as natural grasslands for conservation as they
both play an important role in the fine-scale landscape
functioning of grasslands (Van der Walt et al. 2015). Re-
search on the dynamics of these grasslands also indicated
that despite any current sign of biotic homogenisation
they are facing potential extinction debts (Du Toit et al.
2020). Moreover, this study also showed that the indige-
nous forb species diversity is declining indicating that bet-
ter management, including urban grassland restoration, is
necessary (Du Toit et al. 2020).
Secondly, the growing awareness of the importance of
gardens in the urban green infrastructure led to sever-
al postgraduate studies under the supervision of Stefan
Siebert and Sarel Cilliers. These studies focussed on
biodiversity conservation and the provision of ecosys-
tem services that contribute towards human health and
well-being. Subsequent publications focussed on garden
diversity patterns and their drivers in deep-rural, rural,
peri-urban, urban and metropolitan areas. Of these, a
paper on the importance of socio-economics as drivers
of plant diversity of gardens (Lubbe et al. 2010) was re-
garded as one of four key papers in a recent global study,
which included a meta-analysis of publications on the
relationship between socio-economic inequality and
biodiversity. Other garden studies included investigations
on garden layout and design, the provision of ecosystem
services and the potential to study community gardens
(e.g. health clinic gardens) in the North-West province as
complex social-ecological systems to enhance resilience
in a changing world (Cilliers et al. 2018).
Consequently, a large database was amassed on local
urban plant diversity. The expertise developed in this
research group have led to an intensive involvement
in several international collaborative studies with re-
searchers from several universities in Australia, Brazil,
Chile, Finland, Germany, Hungary, Sweden, UK and
USA. Two global networks that this research group is
actively involved in are Urban Biodiversity Network
(UrBioNet) and Global Urban Soil Ecology and Ed-
ucation Network (GLUSEEN). UrBioNet, is a global
biodiversity network that supports urban biodiversi-
ty research, monitoring and practice in three working
groups, namely social-ecological linkages, urban biodi-
versity patterns and traits, and urban biodiversity mon-
itoring and planning (urbionet.weebly.com). GLUSEEN
focuses on the study of urban soil ecological systems
(www.gluseen.org). As part of this network a compar-
ative study was completed on soil biodiversity and soil
decomposition in public green spaces, ruderal areas,
remnant natural areas and natural areas in five cities
in four countries (including South Africa). From both
networks several leading papers were published (e.g.
Aronson et al. 2016; Epp Schmidt et al. 2017).
Furthermore, this research group is also involved in trans-
disciplinary research and training in collaboration with
urban planners and landscape architects locally and glob-
ally. The main focus is on green infrastructure planning
and several projects such as the value of urban green
areas and the importance of ecosystem services in plan-
ning and design have been completed (e.g. Ahern et al.,
2014). Research on these issues has also led to the devel-
opment of a booklet for the SA Cities Network suggesting
ways of guiding future green infrastructure planning and
management in South Africa (www.sacities.net).
New specialisation elds:
Geoecology and Proteomics
Botany at the NWU has its roots in the study of plant
morphology, plant physiology, plant ecology and plant

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diversity. With the appointment of Stefan Siebert as cu-
rator of the herbarium in 2007, this scope broadened
to include phytogeography. This research interest al-
lowed him to collaborate since 2010 on interdisciplin-
ary biodiversity projects, primarily for the South African
National Biodiversity Institute and the South African
Environmental Observation Network. He specifically in-
vestigated how the diversity and distribution patterns of
plants and arthropods are altered when ecosystems are
exogenously disturbed in agricultural, mining and urban
environments (Lubbe et al. 2010; Siebert et al. 2021).
During this time he also established geoecology as a
new research field at the university. Extensive collabo-
ration with Nishanta Rajakaruna (California Polytechnic
State University) and Marthie Coetzee (Geology subject
group, NWU) through the National Geographic Society
has led to various research projects involving geobotani-
cal surveys (Boneschans et al. 2015), heavy metal accu-
mulation by plants (Siebert et al. 2018) and biological
soil crusts (Venter et al. 2018) on ultramafic rocks. He
has expanded his research to include lichens and is cur-
rently studying the interactions of plants with other rock
types, such as banded ironstone, dolomite and gypsum.
The establishment of Botany on the Mahikeng campus
of NWU in 2017 has strengthened the subject group’s
expertise in plant biology and biotechnology. Oziniel
Ruzvidzo and Tshegofatso Dikobe have a strong re-
search interest in plant proteins. Proteomics is there-
fore the youngest research discipline in Botany at the
NWU. They collaborate internationally with the Uni-
versity of Perugia (Italy), and the Whenzhou-Kean Uni-
versity (China). Specifically, their work on adenylate
cyclases is important as these enzymes are increasingly
recognised as essential parts of many plant processes
including biotic and abiotic stress responses (Chatukuta
et al. 2018). It is increasingly clear that plant genomes
encode numerous complex multi-domain proteins that
harbour functional adenylyl cyclase. These proteins
have well-documented roles in plant development and
responses to the environment. Hence, Botany staff on
the Mahikeng campus conduct research to better un-
derstand the intramolecular mechanisms that govern
the cellular and biological functions of these proteins
(Ruzvidzo et al. 2019). The findings of their work have
vast applications in agriculture.
Conclusions
For the past 100 years Botany at the NWU contribut-
ed considerably to varied research and development
disciplines. From the discussion of the research under-
taken over the years it can be seen that the focus was
initially on plant physiology and plant systematics, and
plant ecology has been included since 1963. Over the
last two decades more emphasis has also been placed
on different sub-disciplines in ecology studying natural,
degraded and anthropogenic ecosystems in terrestrial
and aquatic environments. Botany teaching and re-
search at the NWU (and the former PU for CHE) has
over the years and is currently playing a major role in
the development, and contributing to the prestigious
status, of Botany in South Africa. Researchers at NWU
are local and international leaders in their specific fields
of expertise in e.g. plant function, diversity, taxonomy,
aquatic ecology, urban ecology, land degradation and
ecological restoration of natural and disturbed terres-
trial and aquatic ecosystems. Scientists from various
disciplines are also actively involved in collaborative
national and international research and development
projects and forums. It has always been a priority at
NWU to keep a good balance between basic and ap-
plied science within curricula and research.
NWU biological scientists have been and are involved
in projects and programmes to better understand land-
use changes due to natural (e.g. climate) and anthro-
pogenic (e.g. management) impacts. Indigenous plant
diversity is mostly diminished and plant distribution
patterns altered when land-use change is enforced by
people to meet their developmental and economic
needs. Research results indicated that land-use chang-
es dilute the trait redundancy of ecosystems and the
extent of ecosystem services that can be provided by
affected ecosystems. Recent studies on herbaceous dy-
namics, with a specific focus on forbs, contributed to
an improved understanding of ecosystem resilience in
areas exposed to land-use change, especially sub-trop-
ical grasslands and savannas. Different ecological res-
toration methods have been developed and tested in
arid- and semi-arid natural rangelands and implement-
ing them improves vegetation condition, contributes to
increased grazing capacity and enhances sustainable
land management practices. Urban ecological studies
have contributed to knowledge of the ecosystem ser-
vices provided by the urban green infrastructure and
assist in the development of a conservation-oriented
planning, design and management approach in South
African cities. Research on rivers has indicated that
their water quality is modified by activities and pro-
cesses in the water and in the surrounding catchment
area and directly influence phytoplankton and benthic
assemblages. Furthermore, research results have also
contributed to the development and application of
diatom indices for routine riverine water quality bio-
monitoring and the establishment of the South African
Diatom Index (SADI), which reflects land-use chang-
es and pollution events in South African rivers. Plant
ecophysiological investigations quantified the impacts
of elevated carbon dioxide, air pollution and drought
stress on crops and native plants.
Research in Botany at the NWU also contributes im-
mensely to the improvement of the health and well-be-
ing of South Africans from different cultural groups
and socio-economic statuses. Monitoring of species

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functional diversity and patterns in natural and degraded
ecosystems is allowing us to determine when land-use
change negatively affects ecosystem functions and the
services they provide to humans. It prompts for action to
address the subsequent degradation and to put in place
mitigation measures to restore the lost functions and
services. Studying urban areas as complex and adaptive
social-ecological systems enables us to address the spe-
cific ecosystem service needs of all residents, working
towards the development of climate- and food-resilient
cities, towns and settlements. Research on the ecology
and functioning of forbs in grassy ecosystems aims to
secure future ecosystem goods, services and functions.
Forbs as a plant group are important for forage stability
during dry seasons, pollinator resources for food secu-
rity and biodiversity. Research has also contributed to
the sustainable use of the large component of forbs that
are traditionally used for medicine and/or food items
for rural livelihoods. By understanding changes in phy-
toplankton and benthic assemblages of our rivers, and
biomonitoring of water quality using inexpensive meth-
ods, a rapid response to pollution events enables man-
agement interventions leading to improved river water
quality. Local communities can therefore be protected
from the nuisance of toxins produced by harmful algal
blooms and water treatment plants can produce safe
drinking water. From ecophysiological studies it is possi-
ble to identify and introduce alternative climate-resilient
crops, which may in future provide the much-needed
food and nutrient security for sub-Saharan Africa.
Acknowledgements
The authors of this paper wish to acknowledge the
contributions of other Botany colleagues for provid-
ing information about their fields of research, namely
Sandra Barnard, Jacques Berner, Frances Siebert and
Jonathan Taylor. The NWU Records, Archives and Mu-
seum is thanked for allowing the use of archival mate-
rial and images. The three reviewers of this manuscript
are thanked for their useful comments, corrections and
suggestions, which contributed greatly towards the im-
provement of the text.
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