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RGE521S - RANGELAND ECOLOGY - 2ND OPP - JAN 2023 |
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nAm I BI A u n IVE RS ITV
OF SCIEnCE AnD TECHn OLOGY
FACULTY OF HEALTH, APPLIED SCIENCE AND NATURAL RESOURCES
Department of Agriculture and Natural Resources Sciences
QUALIFICATION: Bachelor of Science Agriculture
QUALIFICATION CODE: 07 BAGR
LEVEL:NQF Level 7
COURSE: Rangeland Ecology
COURSECODE: RGE520S
DATE:January 2023
SESSION:January 2023
DURATION: 3 Hours
MARKS: 100
SECOND OPPORTUNITY EXAMINATION
EXAMINER: Angela Lilungwe
MODERATOR: Dr Hilma Amwele
THIS QUESTION PAPERCONSISTSOF 5 PAGES
(Including this front page)
INSTRUCTIONS
1. Answer all the questions.
2. Show clearly all the steps used in any calculations, and units alongside numbers.
3. Failure to follow instructions may results in deduction of marks.
PERMISSIBLEMATERIALSFORSTUDENTS
1. Scientific calculator.
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Question 1
Lab2i the numbered plant parts in the figure below, by writing down each number and
alongside it writing the name of the corresponding plant part.
[10]
-1
I"-
/
2
.~
-3
'
1/ /
--4
/
--5
·1==-=--=-~-:
r-. -·
I1
\\--~ ----
::--1
8
lJ-u,4r-------
Question 2
On the excursion to farm Krumhuk you followed a cow and recorded bites of what it preferred
eating from the rangeland. Write down the formula to calculate the preference index?
[2]
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Question 3
Discuss how the following factors influences the growth processes of plants.
3.1 Grazing
3.2 Rest
3.3 Establishment of seedlings
3.4 Trampling on the soil
3.5 Fire
Question 4
Describe the functions and importance of grazers in nature.
[3]
[3]
[3]
[3]
[3]
[12]
Question 5
5.1 Which out of annual and perennial plants are generally better for livestock, and
why?
(3)
5.2 Which out of annual and perennial plants are generally better for health of the
rangeland, and why?
(3)
5.3 Which out of annual and perennial plants are best adapted to cope with harsh
conditions, and why?
(3)
[9]
Question 6
Name an example of an animal species for each of the following:
6.1 A domestic animal that is a selective browser
(1)
6.2 A domestic animal that is a selective grazer
(1)
6.3 A domestic animal that is a bulk grazer
(1)
6.4 A wild animal that is a bulk grazer
(1)
6.5 A wild animal that is a bulk browser
(1)
[5]
Question 7
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The influence that the tool of trampling, followed by rest, has on the condition of the
rangeland depends largely on the season and the texture of the soil. Explain the differences
in response to trampling in the growing season and dry season between sandy and loamy
soils, and recommend which soil should rather be trampled more in which season.
[10]
Question 8
Copy down the table below except for the contents of the second column, and then
rearrange the contents of the second column so that the most appropriate indicator fits in
the same row alongside the process which is most likely to have taken place.
[8]
Process likely to have taken place
Sheet erosion
Gully erosion
Wind erosion
Fire
A succession of good rainy seasons
Many years of excessive browsing
Overgrazing
Continuous selective grazing
Indicator
Coppice dunes
Large areas of soil capping
Pedestals
The only Boscia albitrunca plants are tall
trees
Lack of mulch cover over the soil
A low decreaser:increaser ratio
A high density of Acacia mellifera
seedlings
Exposed roots on one side of a large
tree
Question 9
Describe the characteristics of a sweetveld?
[5]
Question 10
Different farmers may use different strategies to cope with changing rainfall over the years.
Describe each of the four strategies marked A-D in the diagram below and explain the major
contrasting implications of each.
[12
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:,
C:
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ti)
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,...I
D
Time
....·.....·..... periodsof supplementarfyee~ing(strategyC)
ecologicaclarryingczpacity
livestocknumb,~~usndtr stockingstrategicsA-D
Question 11
11.1 Convert 340 SSUinto LSU.
(1)
11.2 Convert 20 ha/LSU into kg liveweight/ha.
(1)
11.3 Convert 30 kg liveweight/ha into ha/LSU.
(1)
11.4 Suppose a farmer wants to graze his 146 LSUon a paddock of 520 ha during the dry
season. He estimates that one LSUday requires the amount of rangeland in a
representative square of 23m x 23m. For how many days can the paddock be
grazed?
(3)
11.5 Suppose a farmer wants to graze a paddock of 260 ha for 30 days. He estimates that
one LSUday requires the amount of rangeland in a representative square of 28m x
28m. How many LSUcan be stocked?
(3)
11.6 Suppose a paddock of 370 ha is stocked at 16 ha/LSU for 60 days. What will be the
length of the side of a square that represents the amount of rangeland available for
one LSUday?
(3)
[12]
Total Marks 100
END