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

The Department of Botany on the Potchefstroom Campus (formerly Potchef­ stroom University for Christian Higher Education) of the North­West 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 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.


Introduction
The Botany Department of the former Potchefstroom University for Christian Higher Education (PU for CHE) (now part of the NorthWest 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 100year 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 landuse changes. As this is not intended to be a complete review of each research discipline, 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 pregradu 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  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)(1963)(1964)(1965)(1966)(1967)(1968)(1969)(1970)(1971)(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)(1984)(1985) and he will be remembered for his initiative to change the veld garden into a botanical 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)(1987)(1988)(1989)(1990)(1991)(1992)(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)(1995)(1996)(1997), the integrated approach was phased out, and eventually he reinstated the Botany Department with focus on the subdisciplines 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 (2003and 2009, Klaus Kellner (2007-2008

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 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.

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 bechuanicus 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 lifelong dedication. From 1970 to mid1980s, Daan Botha was the resident plant taxonomist and under his supervision various taxonomic studies were conducted on a range of genera, such as Antizoma  (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 mid1990s, 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 Digitaria, 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. Since 2007 taxonomic work has mainly focussed on Boerhavia and Commicarpus in the Nyctaginaceae (Struwig & Siebert 2013 (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 wholeplant 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 stateoftheart opentop 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 ( 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 socalled JIPtest, 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 JIPtest is now 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 JIPtest were il lustrated by several papers on chilling stress in soybean.
Riekert van Heerden joined the department as plant physiologist in the mid1990s 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 CO 2 assimilation, OJIP chlorophyll fluorescence kinetics and nitrogen fixation of test plants, and assessing the constraints on CalvinBenson 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 OJIP chlorophyll fluorescence transient (Strauss et al. 2006 (Smit et al. 2008). Studies using OTCs included the physiology of SO 2 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 CO 2 concentration of the air in the OTCs allowed assessment of the effect of elevated atmospheric CO 2 concentrations to obtain insight into the effects of increased atmospheric CO 2 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

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 (EcoRehab) 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. . DLDD re search in terrestrial ecology excelled at NWU and many postgraduate 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 semiarid 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 socioeconomics 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 longterm 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 lifeform 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 Subtropical 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 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 earlycareer 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)(2003)(2004)(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 bioindicators of environmental conditions. As part of his PhD thesis he tested the application of diatombased 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. 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 wellknown 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 openended agreement (Tay lor et al. 2011) as the NWU was becoming a centre for diatom studies (especially taxonomy) in the mid2000s. 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 landuses, 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 (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 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 firstever study on the description of plant communities in different landuse 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 landuse areas such as vacant lots, in tensively managed areas, railway reserves, natural and seminatural 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 conservationorientated 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 diumsized 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 socioeconomic 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 finescale 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 wellbeing. Subsequent publications focussed on garden diversity patterns and their drivers in deeprural, rural, periurban, urban and metropolitan areas. Of these, a paper on the importance of socioeconomics 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 metaanalysis of publications on the relationship between socioeconomic 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 NorthWest province as complex socialecological 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 socialecological 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).

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 subdisciplines 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 landuse change is enforced by people to meet their developmental and economic needs. Research results indicated that landuse 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 landuse change, especially subtrop ical grasslands and savannas. Different ecological res toration methods have been developed and tested in arid and semiarid 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 conservationoriented 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 landuse 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 wellbe ing of South Africans from different cultural groups and socioeconomic statuses. Monitoring of species functional diversity and patterns in natural and degraded ecosystems is allowing us to determine when landuse 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 socialecological systems enables us to address the spe cific ecosystem service needs of all residents, working towards the development of climate and foodresilient 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 climateresilient crops, which may in future provide the muchneeded food and nutrient security for subSaharan Africa.