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European Journal of Applied Sciences – Vol. 11, No. 2
Publication Date: April 25, 2023
DOI:10.14738/aivp.112.13398.
Jordaan, F. P., Brits, Y., & Rooyen, J. N. (2023). The Effect of Continuous Grazing and Rest Rotational Management Systems on
Grass Species Composition, Basal Cover and Production on Three Soil Types in the North West Province, South Africa. European
Journal of Applied Sciences, Vol - 11(2). 88-115.
Services for Science and Education – United Kingdom
The Effect of Continuous Grazing and Rest Rotational
Management Systems on Grass Species Composition, Basal Cover
and Production on Three Soil Types in the North West Province,
South Africa
Franci Petra Jordaan
Department of Agriculture and Rural Development,
Agricultural Research Services, Potchefstroom, South Africa
Yvette Brits
Department of Agriculture and Rural Development,
Agricultural Research Services, Potchefstroom, South Africa
Jaco Nicolaas Van Rooyen
Department of Agriculture and Rural Development,
Agricultural Research Services, Potchefstroom, South Africa
Abstract
Rangelands represent the most extensive land cover type on Earth and many people
depend on these rangelands for their livelihoods and for the ecosystem services
that effect human wellbeing. The impact of grazing on community structure and
ecosystem functioning is a key issue for rangeland management in order to
maximize livestock production and sustainability of the operations. It is a known
fact that soil differences cause differences in the palatability and utilization of
grasses. Year-round continuous grazing is the management strategy used in the
communal areas of the North West Province of South Africa. In this study the effect
of continuous grazing and rest rotation grazing on grass species composition, basal
cover and biomass production on different soil types were assessed. From the
results it was clear that the effect of continuous grazing was the biggest on the
andesitic soils (high clay), then the diabase soils (medium clay), whilst the effect on
the quartzite soils was limited to even positive. In the rest rotation system, the effect
of soil type on the different variables was negligibly small and the rangeland
remained healthy and productive.
Keywords: Communal grazing, Rest rotational, andesitic soils, diabase soils, quartzite
soils.
INTRODUCTION
Rangelands represent the most extensive land cover type on Earth [1, 2]. Approximately one
third of the earth’s land surface is occupied by grazing land ecosystems [3, 4, 5, 6, 7]. Grasslands
or rangelands cover approximately 40% of the Earth’s land surface and represents about 70%
of the agricultural area [8, 9, 10]. In South Africa approximately 72%-75% of the total land area
is suitable only as rangeland for livestock and game [1, 11]. In the North West Province (NWP)
of South Africa, approximately 62% of the total area is rangeland [12, 13]. Rangeland
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Jordaan, F. P., Brits, Y., & Rooyen, J. N. (2023). The Effect of Continuous Grazing and Rest Rotational Management Systems on Grass Species
Composition, Basal Cover and Production on Three Soil Types in the North West Province, South Africa. European Journal of Applied Sciences, Vol
- 11(2). 88-115.
URL: http://dx.doi.org/10.14738/aivp.112.13398
ecosystems are therefore not only important in the world, but also in South Africa and
especially in the NWP of South Africa. Many people in rural and urban areas depend on these
rangelands for their livelihoods and for the ecosystem services that affect human wellbeing [14,
15, 16]. Such ecosystem services often include the maintenance of stable and productive soils,
the delivery of clean water, the sustenance of plants, animals and other organisms that support
human livelihoods, and other characteristics that support aesthetic and cultural values [14].
Briske [2] indicated that because of the expansiveness and heterogeneity of rangelands, aspects
like biodiversity and carbon sequestration can also be included in the list of ecosystem services.
However, in spite of the expansiveness and importance of rangelands worldwide and in South
Africa in particular, it is believed that many of these rangelands are degraded as a result of
excessive livestock grazing as well as poor land management [1, 17, 18, 19, 20].
There are three main types of animal production systems (land-uses) in South Africa’s
extensive rangeland ecosystems, namely communal livestock, commercial livestock and
wildlife (game ranching and nature conservation) [1, 13, 21, 22]. These management systems
differ in: (1) management structure, (2) animal diversity, (3) management of grazing resources,
and (4) products [11, 13, 23]. The commercial livestock system is characterized by a single
manager/owner, who farms with one or at the most two animal species, the management of the
grazing resource is through rotational grazing on uniform vegetation units (ecotopes) and the
product produced is a high-quality single product for domestic and international markets [11,
20]. An ecotope is defined as the smallest ecologically distinct landscape feature in a landscape
mapping and classification system [24, 25]. Commercial systems are thus relatively intensive
systems where long-standing choices regarding livestock type and grazing system are made,
but the manager/owner may alter animal numbers year by year [26].
In communal rangelands, however, cattle support multiple livelihood strategies and are used
for milk, traction, bride-wealth, investment, manure, ceremonial slaughter and transport but to
mention a few [16, 27, 28]. According to Smet & Ward [11] communal livestock systems are
characterized by multiple owners farming with many different animal species. The
management system is normally continuous grazing (grazing a particular rangeland
throughout the grazing season, year after year [29]) of diverse vegetation and the products are
high quantities and a diversity of products mostly for own use. Animal sales in communal areas
are generally low – because of this Wessels et al., [30] describe communal areas as generally
characterized by high human populations, overgrazing, soil erosion, excessive wood harvesting
and increases in unpalatable plant species. According to Shackleton [31] and Meadows &
Hoffman [32] livestock numbers in communal areas are 2-4 times higher than the
recommended stocking rates and twice that of commercial farms.
Communal land in South Africa is subject to a variety of tenure systems but most of the South
African communal areas are open-access systems rather than being managed as common
property [26, 27, 33, 34]. In open access situations users have privilege with respect to the use
of a particular resource as nobody has the legal right to exclude them, but they have no actual
rights to the resource [34]. The communal areas in the NWP are all open-access systems where
year-round continuous grazing is the management system – there is thus little to no control
over the animal numbers or where the animals will graze in the communal areas, whilst the
commitment to natural resource management is also little to none [27, 35]. This type of
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European Journal of Applied Sciences (EJAS) Vol. 11, Issue 2, April-2023
continuous grazing is well known to result in severe loss of plant basal cover, meaningful
changes in the grass composition and in the grass biomass production [13, 19, 20, 36]. Because
of the open-access tenure system a growing number of livestock will populate the rangeland
and will eventually exceed its ecological carrying capacity, which will lead to rangeland
degradation. It is a known fact that the communal areas in the NWP are 200% to 600%
overstocked [35, 37]. A comprehensive study was done in 367 magisterial districts of South
Africa in 1999, where experts of these districts had to give inputs, amongst other things, about
the rangeland condition, soil condition, and reasons for the status of the rangelands and soils
in these districts [38]. Results from this study showed that the mean values, for the severity of
rangeland degradation in the NWP was almost three (3) times (63%) higher in the communal
areas than in the commercial areas whilst the mean values for the severity of soil degradation
was four (4) times (±80%) higher in the communal areas than in the commercial areas [13, 39].
Overstocking and overgrazing in the communal areas thus not only changes the structure and
composition of the vegetation, but it also affects the soil structure as well as the relationship
between water and the microclimate [40]. It is known that soil compaction and soil
temperature increase as degradation increase due to an increase in grazing intensity [41, 42].
Water infiltration decreases and water run-off increases in most soil types as the grazing
intensity increases, whilst the organic matter content decreases with overgrazing [41, 42, 43].
Grazing intensity not only has the potential to modify soil structure, function, and capacity but
also to store organic carbon (OC) and could significantly change grassland C-stocks [10].
According to these authors recent studies have suggested that intensive livestock management
has led to C losses from many grasslands around the world and therefore, grassland soils could
potentially become a source rather than a sink for greenhouse gas (GHG) emissions.
The spatial extent of the NWP in South Africa is 105 703.4km2 [44]. The total land used for
communal farming is 3 312 873ha of which 2 360 898ha (±62%) is rangeland. The main
livestock profile for the communal farmers is 45% goats, 40% cattle and 15% sheep [45]. The
total number of farming units in the communal sector are 147 400 [45]. The communal sector
of the NWP is thus characterized by a high number of people and animals on small farming
units. This might be the reason why it was indicated that both soil and rangeland degradation
in the NWP is almost three to four times higher in communal farming areas that in commercial
farming areas [39, 46].
Certain communal areas, especially in the western parts of the NWP, are characterized by
homogeneous geology and soil type. However, most of the communal areas in the NWP are
characterized by different geological parent rocks and soil types in one area. It is a known fact
that soil type has an influence on the palatability or acceptability of grass. A study was done on
a farm of the Department of Agriculture and Rural Development (DARD) of the NWP where two
management strategies were mimicked: (1) a continuous grazing system (communal area) that
consisted of different geological parent rocks and thus soil types, and (2) a rest rotational
system that also consisted of the same soil types that were found in the continuous system.
Rotational grazing is where livestock is moved from one paddock to another on a scheduled
basis [29, 47]. Rest rotation on the other hand is where one or more paddocks receive a 12-
month (seasonal) period of non-use or rest, whilst the other paddocks absorb the grazing load
[29].