Name: ___________________________
Marks:
57
ESS 2 - Welcome back Test
1.
D
2.
C
3.
C
4.
C
5.
A
6.
C
7.
C
8.
A
9.
D
10.
D
11.
A
12.
C
13.
B
14.
D
15.
C
16.
D
17.
B
18.
B
19.
C
20.
C
21.
A
22.
D
23.
C
24.
B
25.
B
26.
A
27.
C
28.
D
29.
B
1
30. No mark scheme available
31.
C
32.
(a)
(b)
(c)
(d)
(e)
Coal use has decreased proportionally → better for environment
as less sulfur/acid rain/less smog [1]; oil use has increased
→ oil spills in oceans [1]/carbon dioxide released to atmosphere
as in coal and natural gas combustion [1]; proportional increase
in ‘cleaner’ fuels of hydro-electric and nuclear is small [1];
credit any reasonable explanation [1]
3 max
Allow [2] for advantages and [2] for disadvantages.
e.g. nuclear: advantages – cheap electricity [1]; no release of
carbon dioxide [1]/
disadvantages – possibility of radioactivity release [1]; expensive
to build nuclear power stations [1]; danger of acquisition of nuclear
material by terrorist groups [1]; problems of waste disposal [1];
expense of eventual decommissioning [1]
4 max
Name [1]; evaluation [2]
e.g. wood [1]; can replant trees that are felled [1]/to provide a
sustainable yield [1]/large volume required [1]/heat of
combustion is not as high as fossil fuels [1]/seldom used to
generate electricity [1]/any reasonable points [1]
3 max
Ecological footprint of a population is the area of land that would
be required to provide all its resources and assimilate all its wastes
(from the subject guide) [1]; land in the same vicinity as the
population [1]/is the inverse of carrying capacity [1]; for
Singapore, the population requires 264 times the land area of
Singapore to maintain it [1]; Singapore is not self-sustaining [1]/
Singapore imports most requirements and exports wastes [1]
3 max
Ecological footprint will decrease in size [1]; because vegetables
require less energy input than meat [1]/eating meat adds another
link in the food chain – energy is lost at each trophic level [1]
2 max
[15]
33.
(a)
Description:
simple count at ground level;
tag/mark counted individuals;
use of aircraft/count from air;
count individuals in a known area and extrapolate for the area
of the whole park;
use information from previous census/survey;
capture – mark – release – recapture/Lincoln index;
Evaluation:
problems due to very large areas;
capture – mark – release – recapture method possibly inappropriate
for large mammals;
density of population in different habitats might vary;
2
some individuals might be concealed by vegetation;
seasonal variations/migration habits of elephants;
problem of replicating sampling;
high cost of some methods;
To receive full marks, answers must have at least one evaluation,
i.e. award only [3 max] for describing method.
(b)
count and identify organisms;
in a specified period of time;
defined number of collectors;
calculate relative abundance of organisms;
use of Simpson’s diversity index;
N ( N  1)
D=
;
n(n  1)
other appropriate diversity index;
higher index value implies greater diversity/OWTTE;
sample areas/quadrant;
replicate countings in both ecosystems under similar conditions;
compare values;
replicate countings in both ecosystems under similar conditions;
compare values;
Any other reasonable points.
4 max
5 max
[9]
3