Floristic assessment of grassland diversity loss in SA

Abstract

Land-use effects on grassland flora are difficult to predict due to
poor understanding of species losses caused by transformation.To determine changes in species diversity and composition by comparing transformed with untransformed grassland. Floristics of paired plots were sampled within 18 transformed sites
(representing agricultural and urban land-uses) and neighbouring untransformed
grassland. Endemic and threatened species were negatively affected by transformation, particularly species with belowground bud-banks and storage organs. Species composition, with clear shifts in dominant families, was changed by over 90% on average by transformation. Land-use transformation lead to the loss of native species and increased alien invasive species.

Full text

BOTHALIA – African Biodiversity & Conservation
ISSN: (Online) 2311-9284, (Print) 0006-8241
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Authors
1M. Muller
1S.J. Siebert
2B.R. Ntloko
1F. Siebert
Aliations
1Unit for Environmental Sciences
and Management, North-West
University, Private Bag X6001,
Potchefstroom 2520, South
Africa.
2Letšeng Diamonds, cnr Kingsway
and Old School Road Maseru,
P.O. Box 12508, Maseru 100
Lesotho.
Corresponding Author
Prof. S.J. Siebert,
stefan.siebert@nwu.ac.za
Dates
Submitted: 20 September 2019
Accepted: 1 December 2020
Published: 24 February 2021
How to cite this article:
Muller, M., Siebert, S.J., Ntloko, B.R.
& Siebert, F., 2021, ‘A oristic
assessment of grassland
diversity loss in South Africa’,
Bothalia 51(1), a11. http://dx.doi.
org/10.38201/btha.abc.v51.
i1.11
Background: Land-use effects on grassland flora are difficult to predict due to
poor understanding of species losses caused by transformation.
Objectives: To determine changes in species diversity and composition by com-
paring transformed with untransformed grassland.
Methods: Floristics of paired plots were sampled within 18 transformed sites
(representing agricultural and urban land-uses) and neighbouring untransformed
grassland.
Results: Endemic and threatened species were negatively affected by transfor-
mation, particularly species with belowground bud-banks and storage organs.
Species composition, with clear shifts in dominant families, was changed by over
90% on average by transformation.
Conclusion: Land-use transformation lead to the loss of native species and in-
creased alien invasive species.
Introduction
Land-use change threatens the persistence of many grassland ecosystems
worldwide (Bond 2016). Grasslands are hyper-diverse ancient ecosystems,
habitats and communities, supporting many endemic and threatened species
(Carbutt, Henwood & Gilfedder 2017). Habitat transformation threatens the
integrity of these systems through soil disturbance and the removal of plant
biomass and species, and the effect is widely recognised and measurable (Her-
ben, Chytrý & Klimešová 2016; Miller, Roxburgh & Shea 2011). The poor
understanding of forb dynamics in grassland necessitates a closer look at flo-
ristic change and whether land-use change leads to species losses or gains in
transformed grassland (Veldman et al. 2015).
In South Africa the Grassland Biome covers approximately one third of the land
surface (Carbutt et al. 2011). The extent of grassland is defined on the basis of
vegetation structure, as well as environmental factors including mean summer
rainfall and minimum winter temperatures (Mucina & Rutherford 2006). The
Grassland Biome is one of the most at-risk South African biomes, with 40–60%
irreversibly modified, and less than 3% formally protected (Little, Hockey &
Jansen 2015). The intactness of unprotected South African grasslands is threat-
ened as there is an increase in the intensity of agriculture and afforestation
(O’Connor & Kuyler 2009; Botha et al. 2017) and urban and industrial devel-
opment activities (Siebert, Van Wyk & Bredenkamp 2001; O’Connor & Kuyler
2009). Changes in composition, structure and functioning of these grasslands
influence the ability to deliver fresh water, soil formation, climate regulation
and reduction of disaster risk (Egoh et al. 2011), and in addition, probable loss
of biodiversity and grassland production (Everson & Everson 2016).
A oristic assessment of grassland
diversity loss in South Africa

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O’Connor and Kuyler (2009) have meticulously investi-
gated the impact of land-use on the biodiversity integ-
rity of moist grasslands in South Africa and highlighted
the loss of useful plants from an ecosystem services
perspective. Our study focusses on biodiversity intact-
ness in that it specifically considers loss of native floristic
diversity. It places special emphasis on the indigenous
forb component that is fast moving up the research
agenda (Siebert & Dreber 2019).
Materials and methods
Study area
Eighteen study sites were selected in four bioregions of
the Grassland Biome, as well as a tropical bioregion of
the Indian Ocean Coastal Belt Biome of South Africa
(Figure 1). The chosen grasslands occurred at altitudes
ranging between 30 and 3 100 m above sea level, with
ten sites between 1 000 and 1 800 m. The mean annu-
al temperature for the grassland sites ranged from 10 to
21°C, with an overall mean of 16.3°C (median 15.9°C).
June to August are the coldest months with mean frost
days per annum varying between 0 and 96, with a
mean of 25 (median 28) across all study sites (Mucina
& Rutherford 2006). All sites experience summer rain-
fall ranging from 600 to 1 000 mm per year and a mean
of 761 mm (median 717 mm) across sites. Twelve sites
receive less than 800 mm per annum.
Field surveys
Two dominant land transformation types in the Grass-
land Biome were included in this study, namely agri-
culture and urbanisation (Neke & Du Plessis 2004).
Floristic data were gathered from 18 sites. At each site,
sampling was conducted in four plots in untransformed
grassland, each paired with a plot in an adjacent trans-
formed land-use (i.e. eight plots per site), no more than
150–250 m apart. All 144 plots were surveyed in late
spring or early to mid-summer. Each 100 m2 plot was
divided into 25 subplots of 4 m2 each to record species
occurrence and abundance. Species were identified in
the field and photos were taken for later confirmation.
Floristic data from the subplots were combined to com-
pile a total inventory for each 100 m2 plot.
Plant species nomenclature and classification follow
Ranwashe (2019). Naturalised and invasive categories
are according to Department of Environmental Affairs
(2016). Life and growth forms of plant species were
Figure 1. Location of the 18 study sites in the Grassland Biome of South Africa. Land-use transformation at localities: Agriculture, af-
forestation: 1, 2, 3; field margins: 4, 5, 6; abandoned fields: 7, 8, 9; urban, green space: 10, 11, 12; peri-urban: 13, 14, 15; mine
rehabilitation: 16, 17, 18.

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obtained from Germishuizen and Meyer (2003). Cate-
gories of threat were obtained from the Red Data List
of South African Plants (South African National Biodi-
versity Institute 2017).
Species abundance (N) was calculated as the total
number of individuals and species richness (S) as the
total number of species within each 100 m2 plot. The
Shannon–Wiener (H’) and Pielou (J’) indices were ap-
plied to plot data to calculate alpha diversity and even-
ness respectively. All above values were calculated us-
ing Primer (2007).
Data analysis
Non-Metric Multi-Dimensional Scaling (NMDS) anal-
ysis in Primer (2007) was used to explore changes in
species composition between transformed and un-
transformed grasslands. Permutational Multivariate
Analysis of Variance (PERMANOVA) was performed us-
ing species abundance data. Analyses were conducted
with 999 permutations using Bray–Curtis similarity and
Type III sums of squares after a square root transforma-
tion of species data to reduce the influence of common
species. To account for location variability in the paired,
nested sampling design, plots were treated as a random
variable nested within a transformation type (i.e. urban
or agricultural), which were treated as the fixed factor.
Pair-wise test results indicated the strength of the dif-
ference between transformed and untransformed plots.
Similarity Percentage Analysis (SIMPER) was applied
to determine which forb and grass species contribut-
ed the most to differences between transformed and
untransformed grasslands. Simple paired t-tests were
applied to test for significant differences between un-
transformed and transformed plots for selected diver-
sity measures. Percentage decrease in richness and
abundance of species per growth/life form, threat sta-
tus, endemism and for alien taxa was calculated from
the statistical means.
Results
Floristics
Overall, 1 146 plant species were recorded, of which
144 were non-native. The untransformed grassland
contained 962 species, which included 35 naturalised
and 15 invasive taxa (5%), 175 South African endemics
(18%) and 20 threatened species (2%). The transformed
grasslands had 582 species, including 92 naturalised
and 46 invasive taxa (24%), 47 South African endemics
(8%) and six threatened species (1%).
The most prominent families in the localities were the
Asteraceae, Poaceae, Fabaceae and Cyperaceae in or-
der of most species diverse (Table 1), whereas the Poa-
ceae were most abundant (Table 2). It is evident that
transformation is less favourable to the Asteraceae and
Fabaceae, and more beneficial to the Cyperaceae and
especially the Poaceae.
Habitat transformation affects the number of species
present per family. The geophytic Hyacinthaceae and
Iridaceae showed the largest species losses (18 and 19
species respectively) when grassland is transformed and
Table 1. Top ten families of untransformed and transformed grasslands based on the proportion of each family’s contribution to the total
species pools of 962 and 582 respectively. Superscripts indicate up or down movement in ranking in transformed grassland
Family Proportion of all species (%) Shift in
Untransformed Transformed ranking
Asteraceae 20,4 19,6 1 / 1
Poaceae 12,9 17,1 2 / 2
Fabaceae 10,2 10,1 3 / 3
Cyperaceae 3,6 3,1 4 / 4
Apocynaceae 3,2 1,7 5 / 10 ˅5
Malvaceae 2,5 2,9 6 / 5 ˄1
Scrophulariaceae 2,4 1,5 7 / 11 ˅4
Iridaceae 2,3 0,7 8 / 23 ˅15
Hyacinthaceae 2,2 0,5 9 / 31 ˅22
Lamiaceae 2,1 1,9 10 / 7 ˄3
Amaranthaceae 0,5 2,4 30 / 6 ˄24
Solanaceae 0,6 1,8 36 / 9 ˄27

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the weedy Amaranthaceae and Solanaceae benefitted
in terms of species additions (9 and 5 species respec-
tively; Table 1). Changes in the frequency of species is
even more pronounced (Table 2). Five of the top ten
families that have high frequencies of occurrence in un-
transformed grassland become reduced in transformed
grassland by 73%. These are replaced by five families,
which in turn showed a 75% increase in transformed
grassland (Table 2).
Composition
Changes in the species number and frequency of fam-
ilies is expected to have an effect on the composition
of transformed grassland. The results from a NMDS re-
vealed clustering that supports the untransformed and
transformed grasslands as separate assemblages (Figure
2). Results from the pair-wise tests in PERMANOVA in-
dicated a significant difference in floristic composition
between transformed and untransformed grasslands in
both urban (df = 70, t = 2.17, p = 0.001) and agri-
cultural (df = 70, t = 2.88, p = 0.001) transformation
types (Figure 2). Bray Curtis similarity measures in the
PERMANOVA design reported a low 6.96% and 5.7%
similarity in species composition between transformed
and untransformed agricultural and urban grasslands
respectively. This implies that transformation changed
species composition in grasslands by ~90% on average.
Fifteen most common grass species explained 21.26%
of the dissimilarity between transformed and untrans-
formed grasslands, with species such as Cynodon dacty-
lon and Hyparrhenia hirta weighted towards the former
and Digitaria eriantha and Themeda triandra towards
the latter (Table 3). Comparatively the first 15 forbs spe-
cies only contributed 8.52% to the dissimilarity, with
species such as Cyperus esculentus and Richardia brasil-
iensis weighted towards transformed, and Helichrysum
rugulosum and Scabiosa columbaria towards untrans-
formed grassland (Table 3).
Diversity
Changes in the species composition are expected
to have an effect on species richness and diversity in
transformed grassland. Simple paired t-tests revealed
significantly lower diversity (for all measures, i.e. J’, H’,
S and N) in the transformed grassland (p<0.001, Table
4). Species richness decreased by nearly 50%.
Status
The lower evenness in transformed grassland indi-
cates uneven proportional contribution of individuals
between species and is indicative of some species be-
coming more dominant and others becoming marginal.
Dominance shifts can be ascribed to increased numbers
of alien, invasive and annual species in the transformed
Table 2. Top ten families of untransformed and transformed grasslands based on the proportion of each family’s contribution to total
recorded individuals of 20 640 and 12 042 respectively. Superscripts indicate up or down movement in ranking in transformed
grassland
Family Proportion of all individuals (%) Shift in
Untransformed Transformed ranking
Poaceae 40,2 43,9 1 / 1
Asteraceae 18,3 15,2 2 / 2
Fabaceae 8,4 7,3 3 / 3
Cyperaceae 2,9 3,1 4 / 4
Rubiaceae 2,3 2,2 5 / 6 ˅1
Acanthaceae 2,0 0,5 6 / 19 ˅13
Malvaceae 1,6 1,3 7 / 12 ˅5
Hyacinthaceae 1,5 0,1 8 / 47 ˅39
Commelinaceae 1,2 1,2 9 / 13 ˅4
Lamiaceae 1,2 0,3 10 / 28 ˅4
Verbenaceae 0,6 2,6 22 / 5 ˄17
Amaranthaceae 0,2 2,1 47 / 7 ˄40
Brassicaceae 0,1 1,9 50 / 8 ˄42
Solanaceae 0,3 1,8 33 / 9 ˄24
Myrtaceae 0,25 1,7 36 / 10 ˄26

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grassland, with the former two being >80% lower in
untransformed grassland (Table 4). Threatened and en-
demic species richness and abundance decreased by
>80% in the transformed grassland (Table 4).
Growth forms
When aliens displace extant species (including endem-
ics), certain growth forms become more or less prom-
inent. Species losses (Table 4) were recorded for spe-
cies with underground storage organs and bud-banks
(USOs), such as geophytes (>80%), parasitic plants
and suffrutices (>90%). Succulents were considered
separately from the dwarf shrub growth form and were
also decreased by over 90% in transformed grasslands
(Table 4).
Discussion
Asteraceae and Fabaceae were the most dominant forb
families in both transformed and untransformed grass-
land, a trend that has previously been reported (Botha
et al. 2017). It can be deduced that regenerative traits,
such as wind dispersal and seed dormancy for rapid
colonisation (Asteraceae), ballochory and/or or endozo-
ochory as seed dispersal traits, and resource acquisition
traits, which increase resprouting capacity (Fabaceae),
make them rather resilient to disturbance. However,
the Amaranthaceae, Brassicaceae, Solanaceae and
Verbenaceae benefit from the transformation of grass-
lands and their numbers and dominance increase
through the introduction of weedy, mostly alien, spe-
cies. These groups are renowned for their ability to
colonise frequently transformed man-made habitats
(Pysek, Prach & Smilauer 1995). In contrast, certain
families, such as the geophytic Hyacinthaceae and
Iridaceae, were extensively disadvantaged by habitat
transformation, as they are sensitive to soil disturbance
because their bud-banks are belowground (Fidelis et al.
2014). The general trend is therefore one of species loss
and displacement by a new flora, mostly annuals, with
colonising traits better suited to a transformed environ-
ment, such as creepers, clonal plants and fruit or seed
adapted for exozoochorous or anemochorous dispersal
(Botha et al. 2017).
Many species of ancient grasslands are not tolerant to
anthropogenic disturbance (Siebert 2011). Common
native species disappeared completely where grass-
lands were transformed, such as the grasses Alloterop-
sis semialata (R.Br.) Hitchc. and Schizachyrium san-
guineum (Retz.) Alston, forbs Gerbera ambigua (Cass.)
Sch.Bip. and Haplocarpha scaposa Harv., geophytes
Ledebouria luteola Jessop and Hypoxis argentea Harv.
ex Baker., dwarf shrubs Athrixia phylicoides DC. and
Tephrosia capensis (Jacq.) Pers., and suffrutices Ele-
phantorrhiza elephantina (Burch.) Skeels and Ziziphus
zeyheriana Sond. Other species, such as the palatable
and productive grass, Themeda triandra, which is con-
sidered a keystone species and indicator of undisturbed
grassland (Snyman, Ingram & Kirkman 2013), were
Figure 2: Non-Metric Multidimen-
sional Scaling (NMDS) ordina-
tion for: A, transformed and
untransformed grasslands; B,
within land-use type transfor-
mation. Squares, transformed
grasslands; circles, untrans-
formed grasslands; Empty sym-
bols, urban sites; filled symbols,
agricultural sites.

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severely reduced. Many new, mostly alien species,
enter the transformed system, providing species that
can be considered indicators of disturbance (Morris &
Scott-Shaw 2019), such as the prostrate and grazing-
resistant, Richardia brasiliensis. This study confirmed the
results of O’Connor (2015) that a substantial decrease
in T. triandra and increase in R. brasiliensis are indica-
tive of transformed grassland.
As previously shown, untransformed grasslands have
greater plant species diversity (27%) and richness (92%)
than transformed grasslands (O’Connor 2005; Siebert
Table 3. Similarity percentage analyses (SIMPER) of grass species contributing >0.6% to compositional differences between transformed
and untransformed grasslands. Bold values indicate highest mean abundance. * denotes alien taxa. Superscripts: G, grass; F, forb
Species Av. Cont. Cum. Mean abundance
dis. % % Transf. Untransf.
Themeda triandra Forssk.G2.92 3.067 3.07 1.32 13
Cynodon dactylon (L.) Pers. G 1.853 1.947 5.01 7.85 2.21
Eragrostis curvula (Schrad.) Nees G 1.768 1.858 6.87 5.63 4.85
Eragrostis plana Nees G 1.731 1.818 8.69 5.13 4.32
Hyparrhenia hirta (L.) Stapf G 1.457 1.531 10.22 5.35 2.63
Digitaria eriantha Steud. G 1.326 1.393 11.61 2.43 4.93
Setaria sphacelata (Schumach.) Moss G 1.179 1.239 12.85 1.28 4.89
Aristida junciformis Trin. & Rupr. G 1.148 1.206 14.06 0.74 5.24
Sporobolus africanus (Poir.) Robyns & Tournay G 1.145 1.203 15.26 4.79 0.94
Eragrostis chloromelas Steud. G 1.117 1.173 16.44 1.1 4.56
Pennisetum clandestinum Hochst. ex Chiov. G * 1.115 1.172 17.61 4.65 0
Heteropogon contortus (L.) Roem. & Schult. G 1.109 1.165 18.77 0.17 5.07
Tristachya leucothrix Trin. Ex Nees G 1.014 1.066 19.84 0.9 4.31
Richardia brasiliensis Gomes F * 0.755 0.793 20.63 3.07 0.35
Helichrysum rugulosum Less. F 0.752 0.79 21.42 0.56 3.25
Eragrostis racemosa (Thunb.) Steud. G 0.709 0.745 22.17 0.13 3.1
Cyperus esculentus L. F * 0.695 0.73 22.89 3.1 0.04
Helichrysum nudifolium (L.) Less. F 0.653 0.686 23.58 0.38 2.86
Eragrostis capensis (Thunb.) Trin. G 0.648 0.681 24.27 0.33 2.85
Sisymbrium turczaninowii Sond. F 0.637 0.67 24.94 2.61 0.15
Nidorella podocephala (DC.) Goldblatt & J.C.Manning F0.62 0.652 25.59 0.93 2.17
Hilliardiella oligocephala (DC.) H.Rob. F 0.516 0.542 26.13 0.17 2.26
Tagetes minuta L. F * 0.501 0.526 26.66 2.18 0.07
Scabiosa columbaria L. F 0.487 0.511 27.17 0.38 2.07
Conyza bonariensis (L.) Cronquist F * 0.484 0.509 27.68 1.75 0.4
Commelina africana L. F0.442 0.464 28.14 0.49 1.78
Felicia muricata (Thunb.) Nees F 0.412 0.433 28.57 0.25 1.61
Plantago lanceolata L. F 0.397 0.417 28.99 1.57 0.42
Bidens pilosa L. F * 0.393 0.412 29.41 1.68 0.03
Zornia capensis Pers. F 0.372 0.391 29.79 0.18 1.6
Av. dis.: Average dissimilarity; Cont. %: Contribution %; Cum. %: Cumulative contribution %; Transf.: Transformed; Untransf.: Untrans-
formed. Distance/Similarity measure: Bray-Curtis.

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2011). Species loss was specific to certain growth forms
with underground organs specifically adapted to survive
harsh winter conditions, drought and fire (Bond & Parr
2014; Bond 2016). The loss of these and other foun-
dation species open up niches for colonisation by alien
species (Prevéy et al. 2010). This is problematic, as loss
of native species hampers the grassland ecosystem from
fulfilling all its functions (Zavaleta et al. 2010). Overall,
the situation in transformed grassland is not only one of
species depletion, but increases in woody growth form
dominance is predicted to become more pronounced
in South African grasslands by 2030 (Gibson et al. 2018).
Table 4: Mean values (±SD) of selected diversity measures, growth forms, and alien, threatened and endemic species per plot. Percent-
age decrease is given in brackets. T-test results are reported for diversity measures, with significance set at p < 0.05
Measure Untransformed Transformed df t p
Pielou’s evenness (J’) 0.903 ±0.05 0.849 ±0.08 (6%) 142 4.92 <0.001*
Shannon Diversity Index (H’) 3.595 ±0.2 2.823 ±0.4 (21.5%) 142 13.93 <0.001*
Total species (S) 54.7 ±10.2 28.5 ±7* (47.9%) 142 17.9 <0.001*
Alien 0.9 ±1.1* (87%) 6.9 ±4.4
Invasive 0.5 ±0.9* (82.8%) 2.9 ±3.2
Threatened 0.5 ±0.7 0.1 ±0.4* (80%)
Endemic 6.7 ±3.2 1.3 ±1.4* (80.6%)
Annual 4.7 ±3.4* (39%) 7.7 ±5.4
Perennial 49.9 ±9.3 20.8 ±8.3* (58.3%)
Grass 13.4 ±5.1 7.9 ±3.6* (40.3%)
Geophyte 5.1 ±2.5 0.9 ±0.9* (80.4%)
Forb 23.5 ±5.2 12.3 ±4.4* (47.7%)
Parasitic 5.8 ±2.8 0.1 ±0.3* (98.3%)
Creeper 1.6 ±1.3 0.9 ±1.2 (43.8%)
Dwarf shrub 6 ±2.7 1.6 ±1.3* (73.3%)
Succulent 5.8 ±2.8 0.3 ±0.6* (94.8%)
Suffrutex 5.8 ±2.8 0.1 ±0.4* (98.3%)
Tree/shrub 5.9 ±2.7 4.2 ±6.2 (28.8%)
Total individuals (N) 286.7 ±64 167.3 ±40.8* (41.6%) 142 13.36 <0.001*
Alien 3.6 ±6.9* (90.4%) 37.4 ±26.2
Invasive 1.6 ±3.4* (92.3%) 20.8 ±22.9
Threatened 1.7 ±3.1 0.3 ±0.9* (82.4%)
Endemic 29.2 ±17.1 7.4 ±15.1* (74.7%)
Annual 19.4 ±16.2* (52.8%) 41.1 ±36.3
Perennial 267.3 ±63.5 126.1 ±52.5* (52.8%)
Grass 115.3 ±48.7 73.4 ±35.3* (36.4%)
Geophytic 17.6 ±11.8 3.2 ±4.6* (81.8%)
Forb 104.2 ±36.2 58.6 ±29.1* (43.8%)
Parasitic 23.7 ±14.4 0.2 ±0.6* (99.2%)
Creeper 5.3 ±6.4 3.1 ±4.1 (41.5%)
Dwarf shrub 24.8 ±14.1 5.9 ±7.8* (76.2%)
Succulent 23.7 ±14.4 1.1 ±2.6* (95.4%)
Suffrutex 23.8 ±14.4 0.2 ±1.7* (99.2%)
Tree/shrub 24.1 ±14.1 21.5 ±27.6 (10.8%)

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Conclusion
Major plant families remain floristically dominant after
transformation, but there is a negative impact on over-
all phylogenetic diversity and the promotion of the Poa-
ceae and Cyperaceae. Non-typical grassland families,
with a wide array of disturbance-tolerant traits, show
an increase in phylogenetic diversity, which is main-
ly a consequence of the introduction of alien weedy
species.
Species composition of grassland was transformed by
disturbance and is indicative of better adapted spe-
cies entering the system or existing pre-adapted ones
becoming more dominant due to competition release
and/or altered microclimates and soils (Pysek, Prach &
Smilauer 1995). This is evidenced by the proportion of
grass species increasing, but a large reduction in forb
species with USOs (Fidelis et al. 2014). No evidence
was found for extensive woody encroachment in trans-
formed areas.
This study set out to assess species loss due to trans-
formation and, based on the current data set, it can
be conclusively stated that grassland is severely im-
pacted in terms of its species richness and diversity.
These changes are of concern as grasslands have high
economic value and support the wellbeing of humans
by providing, among others, ecological infrastructure,
carbon sinks, albedo surfaces, plant-based medicines,
food plants and grazing for livestock (Bengtsson et al.
2019). Further studies are needed to determine wheth-
er these floristic shifts can still maintain and provide the
ecosystem services that are expected from grasslands in
South Africa.
Acknowledgements
Our appreciation to Dr Monique Botha, Dr Elandrie
Davoren and Mr Paul Janse van Rensburg for making
plot data available for this study, and to Mr Wynand
Muller for producing the locality map. The South Af-
rican National Biodiversity Institute, South African En-
vironmental Observation Network, National Research
Foundation of South Africa and Letšeng Diamond
Mine, Lesotho, provided financial support to the re-
searchers and students involved in this project.
Authors’ contributions
MM collected field data, conducted data analyses
and contributed to the writing of the manuscript. SJS
planned and coordinated the study, collected field
data, conducted data analyses and co-wrote the manu-
script. BRN planned and coordinated part of the study,
collected field data, and conducted data analyses. FS
collected field data and contributed to the writing of
the manuscript.
Disclaimer
The views expressed in the submitted article are our own
and not an official position of the institution or funder.
Source(s) of support
South African National Biodiversity Institute, South Af-
rican Environmental Observation Network, National
Research Foundation.
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