Scientific Method in Action

1
Scientific Method in Action Group Task

• Group members
• Mabandi Mnisi
• Moses Shitlhelani
• Christopher Shai

2
Scientific Method in Action Group Task
Group members - Mabandi Mnisi, Moses Shitlhelani
and Christopher Shai
Observe / Idea
Question expected answer
Consider the following aerial photo of the SAWC /
Welverdiend area
Answer
Protected area, wildlife (natural grazers)
Communal land, cows only
3
Who eats more - Wildlife or Cows? Chris, Maband,
Moses (and Dave) the Professors Introduction Bac
kground Different land uses affect biodiversity
in different ways. For example, protected
savannas will look and function differently to
communally utilized savannas. Observation
revealed that communal areas seemed to have less
vegetation and more grazing by only a single
herbivore the cow. Alternatively, a protected
area seemed to have more vegetation and a
diversity of herbivores (natural
wildlife). Hypothesis Cows have a greater impact
on vegetation than natural grazers do.
4
Materials and Methods
Choose 1 point in Welverdiend (communally grazed
area) and 1 point in the SAWC (protected
savanna). Mark this central point with a flag.
Using a compass and a tape measure, set up 4x25 m
transects running north, east, south and west way
from your flag. Biomass At every 5 m along each
of your 4 transects (5, 10, 15, 20 and 25m), use
the disc pasture meter to measure the bulk of
vegetation. Record this in cm. Species
composition / Vegetation structure At every 1m
(large step) along each of your 4 transects
(1-25m), record whether the plant closest to your
foot is either a grass (G), a forb (F) or bare
soil (S).
5
Data collection sheet
TRANSECT TRANSECT TRANSECT TRANSECT TRANSECT TRANSECT TRANSECT TRANSECT
Distance (m) N N E E S S W W
Veg Bio Veg Bio Veg Bio Veg Bio
1
2
3
4
5
6

25
6
Results Table 1 Frequency of vegetation and
biomass for naturally and unnaturally grazed
areas.
Vegetation Vegetation Vegetation Vegetation Vegetation
Grass Forb Soil Mixed Biomass (range), mean
SAWC 82 18 0 0 (3-16), 9.27
Welver 67 18 1 14 (0-11), 3.33
The dominant grass species found in the 2 areas
were Urochloa and Eragrostis for Welverdiend and
Urochloa, Panicum and Chloris for the SAWC.
7
Figure 1 Average biomass in naturally and
unnaturally grazed areas.
8
Figure 2 Frequencies of vegetation components
for naturally and unnaturally grazed areas.
9
Discussion Hypothesis Cows have a greater impact
on vegetation than natural grazers do. Our
results showed that communally grazed areas have,
on average, 3x less biomass and a lower grass
frequency, meaning that less of the community is
made up of grass. Also, the dominant grass
species were different between the two
sites. Therefore, we accept our hypothesis. Cows
do have a higher impact on vegetation than do
natural grazers. Reasons for higher
impact Restricted area of cattle Seasonal
movement / migration prevented (concentration of
grazing) No stock control / stocking
densities Type of grazers (mixed feeders in
natural area sharing resources, but bulk grazers
cows in communal area) Heavy trampling (links
to size and high number of cows)