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BRM622S-BASIC RESEARCH THETHODS-1ST OPP-NOV 2024 |
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nAmlBIA unlVERSITY
OF SCIEnCE AnD TECHnOLOGY
FACULTY OF HEALTH, NATURAL RESOURCES AND APPLIED SCIENCES
SCHOOL OF AGRICULTURE AND NATURAL RESOURCE SCIENCES
DEPARTMENTOF NATURALRESOURCESCIENCES
QUALIFICATION: BACHELOROF NATURALRESOURCEMANAGEMENT
QUALIFICATION CODE: 07BNRS
LEVEL: 6
COURSECODE: BRM622S
COURSENAME: BASICRESEARCHMETHODS
DATE: NOVEMBER 2024
DURATION: 3 HOURS
MARKS: 100
FIRST OPPORTUNITY EXAMINATION QUESTION PAPER
EXAMINER(S) Dr. Mark C. Bilton
MODERATOR: Prof. Ben Strohbach
INSTRUCTIONS
1. Answer ALL the questions.
2. Write clearly and neatly.
3. Number your answers clearly.
4. Show your detailed work for calculations.
PERMISSIBLEMATERIALS
1. Calculator
THIS QUESTION PAPERCONSISTSOF 8 PAGES(Excluding this front page)
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Question 1 (Literature searching)
Below is a Zotero report (reference management software output) containing 6x articles
labelled from A- F. Please note, for the purpose of the exam, the abstracts have been
shortened and some authors have been removed.
A)
Ecological responses to recent climate change
Item Type Journal Article
Author Gian-Reto Walther
Author
Eric Post
Author Peter Convey
Author Annette Menzel
Author Camille Parmesan
Author Trevor J.C. Beebee
Author Jean-Marc Fromentin
Author
Ove Hoegh-Guldberg
Author
Franz Bairlein
Abstract
There is now ample evidence of the ecological impacts of recent climate
change, from polar terrestrial to tropical marine environments. The responses
of both flora and fauna span an array of ecosystems and organizational
hierarchies, from the species to the community levels ....
Date
2002-03-01
URL
https://doi.org/ IO. l 038/4 I 6389a
Volume 416
Pages
389-395
Publication Nature
DOI
I 0.1038/4 I 6389a
Issue
6879
Journal
Abbr
Nature
ISSN
1476-4687
Date
Added
20/10/2024, 15:50:30
Modified 20/10/2024, 15:50:30
B)
Global Biodiversity Scenarios for the Year 2100
Item Type
Author
Author
Author
Author
Author
Journal Article
Osvaldo E. Sala
F. Stuart Chapin
Juan J. Armesto
Eric Berlow
Janine Bloomfield
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Author Rodolfo Dirzo
Author
Brian H. Walker
Author Marilyn Walker
Author Diana H. Wall
Abstract
Scenarios of changes in biodiversity for the year 2100 can now be developed
based on scenarios of changes in atmospheric carbon dioxide, climate,
vegetation, and land use and the known sensitivity of biodiversity to these
changes ...
Date
2000-03-10
URL
htt12s://doi.org/ I 0. I 126/science.287 .5459. I 770
Accessed 20/10/2024, 02:00:00
Extra
Publisher: American Association for the Advancement of Science
Volume 287
Pages
1770-1774
Publication Science
DOI
IO. l l 26/science.287.5459.1770
Issue
5459
Date
Added
20/10/2024, 15:50:30
Modified 20/10/2024, 15:50:30
C)
Global Desertification: Building a Science for Dryland Development
Item Type Journal Article
Author James F. Reynolds
Author D. Mark Stafford Smith
Author Eric F. Lambin
Author B. L. Turner
Author Michael Mortimore
Author Rik Leemans
Author Tim Lynam
Author Fernando T. Maestre
Author Miguel Ayarza
Author Brian Walker
Abstract
In this millennium, global drylands face a myriad of problems that present
tough research, management, and policy challenges. Recent advances in
dryland development, however, together with the integrative approaches of
global change and sustainability science ...
Date
2007-05-11
URL
htt12s://doi.org/10.1126/science. l 131634
Accessed 20/10/2024, 02:00:00
Extra
Publisher: American Association for the Advancement of Science
Volume 316
Pages
847-851
Publication Science
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DOI
I0.1 126/science. I I3 1634
Issue
5826
Date
Added
20/10/2024, 15:50:30
Modified 20/10/2024, 15:50:30
D)
Plants and climate change: complexities and surprises
Item Type Journal A11icle
Author Camille Parmesan
Author Mick E. Hanley
Abstract
Anthropogenic climate change (ACC) will influence all aspects of plant
biology over coming decades. Many changes in wild species have already
been well-documented as a result of increased atmospheric CO2
concentrations, warming climate and changing precipitation regimes ....
Date
2015-11-01
URL
httgs://doi.org/ I0.1093/aob/mcv 169
Accessed 20/10/2024, 02:00:00
Volume 116
Pages
849-864
Publication Annals of Botany
DOI
10.1093/aob/mcv 169
Issue
6
ISSN
0305-7364
Date
Added
20/10/2024, 15:50:30
Modified 20/10/2024, 15:50:30
E)
Predicting Chronic Climate-Driven Disturbances and Their Mitigation
Item Type Journal Article
Author Nate G. McDowell
Author Sean T. Michaletz
Author Katrina E. Bennett
'
Author Ku11C. Solander
Author Chonggang Xu
Author Reed M. Maxwell
Author Richard S. Middleton
Abstract
Society increasingly demands the stable provision of ecosystem resources to
suppo11 our population. Resource risks from climate-driven disturbances,
including drought, heat, insect outbreaks, and wildfire, are growing as a
chronic state of disequilibrium results from increasing temperatures and a
greater frequency of extreme events ....
Date
2018-01-01
URL
httgs://www.sciencedirect.com/science/article/gii/SO 169534717302616
Volume 33
3
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Pages
15-27
Publication Trends in Ecology & Evolution
DOI
I 0.1016/j.tree.2017.10.002
Issue
1
ISSN
0169-5347
Date
Added
20/10/2024, 15:50:30
Modified 20/10/2024, 15:50:30
F)
Species diversity: from global decreases to local increases
Item Type Journal A1ticle
Author Dov F. Sax
Author Steven D. Gaines
Abstract
Current patterns of global change can strongly affect biodiversity at global,
regional and local scales. At global scales, habitat destruction and the
introduction of exotic species are contributing to declines in species
diversity ....
Date
2003-11-01
URL
httgs://www.sciencedirect.com/science/article/i;1ii/SO 169534703002246
Volume 18
Pages
561-566
Publication Trends in Ecology & Evolution
DOI
I0.1016/SO I69-5347(03)00224-6
Issue
11
ISSN
0169-534 7
Date
Added
20/10/2024, 15:50:30
Modified 20/10/2024, 15:50:30
la} List the articles, using the identifying letters, in the order they would appear in a
Bibliography/ reference list. (e.g. F, C, D, A, E, B)
[G]
lb} Write article 'F' in the correct format in which it would appear in the
bibliography/reference list, using APA7 style (don't worry about italicformatting, it is
important you show which information "should" be included)
[6]
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le} Below is the text in which the articles were cited ....
"Climate change has already had large impacts on plant communities around the world i)(A;
DJ( ...... ; ...... ). Predictions for some ecosystems suggest that they are nearing tipping
points, beyond which there is no immediate return, and full scale degradation may set in
(iJ(C;EJ( ...... ; ... .. .). This may be particularly so in regions where climate change and heavy
pressure due to land-use change add up to drive ecosystems beyond thresholds (iii)(B;FJ( ...... ;
...... ).
Write the correct "in text formats" for the articles in the positions i) to iii) as defined by APA
7th edition format. Super script letters highlight which articles (A-F}should be included in
each section - but not necessarily in the correct order.
i)
( ...... ;...... )(A;D)
ii)
( ...... ; ...... ) (C;E)
iii)
( ...... ;...... ) (B;F)
[6]
ld) Briefly explain how you would find more relevant articles for reading based on those
already found in the Zotero report.
[6]
Total marks [[24))
Question 2 {Observational Study)
On 8 commercial farms in the Waterberg Landscape, you set up a study to ask the broad
question "what is the effect of debushing on rangelands?"
Within this study you observe areas that are non-debushed, treated by chemical debushing
techniques, and areas which are thinned mannually.
2a) What treatment levels should be repeated on every farm in order to answer the
question well/ remove unwanted variance ?
[3]
2b) Name two response variables you would observe in order to answer the broad
question?
[2]
2c) How many explanatory variables are included in this study?
[1]
2d) Name some confounding effects you would take into consideration in the study design ?
i.e. i) things you would try to keep the same?
[3]
ii) things you would take extra measures of?
[3]
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2e) Considering one of your response variables, state one hypothesis you will test ?
[4]
Total marks [[16]]
Question 3 (Experimental study)
On a commercial farm the effects of reduced rainfall and grazing intensity are tested in a
fully factorial design i.e. including all combinations of treatment levels. Shelters are erected
to reduce the amount and rainfall reaching the ground surface, and areas are cut manually
either 2x or 4x per year to simulate grazing intensity. Perennial grass density is measured as
a response of rangeland health.
Here there are two treatments/explanatory variables - Rainfall and Grazing intensity.
3a) What controls (if any) would you include in the study in order to test the impact of the
stressors on rangeland health ?
[3]
3b) If all combinations of treatment levels are included (including any controls), how many
treatment levels are there in total ? Draw a diagram to show all treatments levels included.
[6]
3c) i) Name "the three R's" important to consider in experimental design
[3]
ii) Describe how you would use each of these three R's to set-up the full experiment
[9]
3d) State three hypotheses you would test for in this study?
[7]
For many "basic" statistical techniques we assume a) normal distribution of the error terms
and b) consistent variance across our samples (Homoscedasticity).
3e) In the current experiment, the response variable is "Perennial plant density".
i. Explain why this is unlikely to follow model assumptions when tested.
[3]
ii. Explain how you might correct for this, so that the error terms DO match model
assumptions.
[4]
Total marks [[35]]
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Question 4 (Data presentation and interpretation)
You performed a greenhouse experiment to test how fertilisation affected the growth of the
annual grass Melinis repens subsp. grandif/ora. Therefore, you planted seeds into 10 pots
which were unfertilised, and 10 pots which contained fertiliser. At the end of the growth
cycle, you measured the height of the individuals in centimetres as follows:
Unfertilized Fertilized
1
16.5
28.8
2
18.2
45.1
3
25.6
37.2
4
19.5
32.4
5
22.6
31.6
6
27.2
33.1
7
18.8
37.9
8
13.2
33.3
9
25.4
36.5
10
26.3
38.2
4a) Calculate the average for each treatment. Show your calculations.
[4]
4b) The standard error has been calculated as 4.77 for the unfertilized treatment, and
4.59 for the fertilized treatment. Present your results graphically.
[7]
4c) In your opinion, is there a significant difference between the two treatments?
Explain why you come to this conclusion.
[3]
4d) You carried out an observational study counting the number of individuals of the
grazing tolerant grass Eragrostis /ehmanniana and the grazing sensitive grass Antephora
pubescens in 10m x 10m plots. You record the density of both species on either highly
grazed areas, or areas of low grazing.
After collecting the data, you perform an ANOVA to test the statistical differences of the
different species in the differently grazed areas.
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Below is both the figure and ANOVA table for your outputs.
35
30
- 25
E 20
00....
-0 15
-.·Cuc=; - 10
Ca,
D5
• Hgh grazingintensity
Lowgrazingintensity
0
&agrostislehm-anman-a
Amphora {JW':!SCMS
Species
Table 1: ANO VA table for the densities of two grass species counted on areas of different
grazing intensity.
Effect
d.f.
F-value
p-value
Species
1
12.19
<0.01
Grazing
1
0.13
0.720
Species x Grazing
1
86.01
<0.0001
Write out a statistical statement suitable for the results section of your thesis, that
describes the result of the AN OVA test.
[11]
Total marks [[25]]
*********** ENDOF EXAM***********
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