NCEA Level 1 Agricultural and Horticultural Science (90158) 2009 — page 1 of 5
Assessment Schedule – 2009
Agricultural and Horticultural Science: Describe the properties and management of
soil (90158)
Evidence Statement
Q
Evidence
Achievement
Achievement with
Merit
Achievement with
Excellence
ONE
(a)
Example:
EITHER
The larger the particles are in a soil, the
more easily it will drain [Description (D)]
and the less water will be available for
plant processes such as photosynthesis
and respiration. [Explanation (E)]
OR
The smaller the particles are in a soil,
the more difficult it will be to drain (D)
and more water will be available for
plant processes such as photosynthesis
and respiration. (E)
(b)
(ii)
(b)
(iii)
EITHER
Management practice: Irrigation
Irrigating involves applying water to the
soil, so the amount of water available to
plants will increase. (D) Plants can use
this water for plant processes such as
photosynthesis and respiration. (E)
Irrigation can be applied when water is
required by the plant, whereas compost
relies upon the soil holding water. So
once the water is not available for the
plants, plant growth will be detrimentally
affected. [Justification (J)]
OR
Management practice:
Adding compost material
Adding compost material to increase
the organic matter levels will increase
the ability of the soil to hold water (D)
as the particles are bound together,
creating many small pores. This means
water will be available to plants for
longer during droughts (E). Water
applied by irrigation would quickly drain
with the sandy soil, because it has large
pores and is free-draining. Irrigation
water would be available to plants for
only a limited amount of time (J).
Describes one
effect of particle
size on drainage,
OR
how water
availability
affects plant
growth (must
relate to a
specific plant
process).
Describes one
aspect of soil
particles relating to
particle size and
drainage,
AND
explains how
water availability
affects plant
growth.
M1
A1
Describes the
selected
management
practice.
Explains how this
management
practice increases
water available for
plant growth.
A2
M2
Justifies the
selection of ONE
of the
management
practices
compared with the
other management
practice in terms of
usefulness in
ensuring soil water
is better
maintained.
E
NCEA Level 1 Agricultural and Horticultural Science (90158) 2009 — page 2 of 5
Q
Evidence
Achievement
Achievement
with Merit
Achievement
with Excellence
TWO
(a)
The larger the particles are the more
air the pores hold and so the warmer
the soil will be in the spring. (D)
The warmer the soil temperature, the
faster plant chemical processes such
as germination, respiration, nutrient
absorption and plant growth will occur.
(E)
Describes how
particle size
affects soil
temperature,
OR
how temperature
affects plant
growth (need to
link to specific
processes, eg
speeds up
chemical
processes or
slows down the
rate of
respiration).
Describes how
particle aeration or
drainage (due to
particle size)
affects soil
temperature,
AND
links ideas
towards
explaining how
aeration affects
temperature and
plant growth.
M1
A1
(b)
(i)
Drainage consists of the removal of
excess water from soil, so that the soil
temperature will increase more quickly
(D).
The removal of excess water will result
in more air within the pore spaces. Air
heats up faster than water, so the soil
will warm up more quickly than if the
pore spaces are full of water. (E)
(b)
(ii)
Drainage will remove the influence
water has on keeping the soil cooler
over the winter, whereas compost can
retain water, keeping the soil cooler.
Compost will only warm the soil if it is
sunny, whereas drainage will occur
regardless of the weather or season.
Ultimately, using compost will be less
effective, as it will decompose with
time and need to be replaced in large
quantities, whereas once drainage is
installed it lasts longer, so in the long
term is easier to use. (J)
Describes what
the management
practice of
drainage is, and
what it results in.
A2
Describes what
the management
practice of
drainage is, and
what it results in,
AND
links ideas
towards
explaining how
the use of
drainage as a
management
practice affects
soil temperature.
EITHER makes
clear links to water
leaving space for
air and air heating
up faster than
water,
OR
makes a valid
point about
seasons or ease
and effectiveness.
M2
Links ideas
towards justifying
how the use of
drainage as a
management
practice is a better
solution than the
application of
compost to
increase soil
temperature and
plant growth.
Must relate to
seasons and ease
and effectiveness.
E
NCEA Level 1 Agricultural and Horticultural Science (90158) 2009 — page 3 of 5
Q
Evidence
Achievement
Sand has large particles, with large
pores between them. This allows water
to flow easily through a sandy soil
which can leach water-borne nutrients
(D), so their availability for plant growth
is reduced. (E)
Correctly
describes the
effect particle size
has on nutrient
retention,
OR
how nutrients
affect plant growth
(increase or
decrease growth
accepted).
Achievement
with Merit
Achievement
with Excellence
THREE
(a)
Clay has small particles, with small
pores between them, so drainage is
slower and it is more difficult to leach
nutrients (D), so their availability for
plant growth is greater (E).
A1
Correctly
describes the
effect particle size
has on nutrient
retention,
AND
links ideas
towards
explaining how
nutrient retention
affects plant
growth (increase
or decrease
accepted).
M1
(b)
(ii)
(b)
(iii)
EITHER
Selected management practice:
Applying effluent
This involves applying animal
excrement, containing nutrients, to the
soil which the plant can use. (D)
The nutrients mix with the soil water
and are then absorbed by the plant to
be used in chemical plant processes.
Effluent from animals is high in organic
matter, which is able to bind soil
particles together, improving the soil
structure. This improves such physical
properties as drainage and aeration.
(E)
Applying effluent will increase the
nutrient levels of the soil, which the
plant needs, and improve the physical
properties. Adding lime only adds
calcium, which is not required by the
plant in large amounts. (J)
OR
Selected management practice:
Adding lime
This involves applying lime to change
the soil pH or to add calcium as a
nutrient or to flocculate the clay
particles. (D)
Lime can alter the pH of the soil,
unlocking nutrients which are present
but may not have been available to the
plant. These nutrients are then able to
be absorbed by the plant, to be used in
chemical plant processes.
The lower the pH, the lower the
microbe and worm activity for breaking
down organic matter.
Lime can flocculate clay particles in the
Describes what
the management
practice of either
applying effluent
or adding lime
results in.
A2
Links ideas
towards
explaining how
the use of this
management
practice improves
plant growth
through improved
chemical and
physical
properties of soil.
M2
Links ideas
towards justifying
how the use of
this management
practice is a better
solution than the
rejected
management
practice in terms
of improving
pasture growth
through improved
chemical and
physical
properties.
E
NCEA Level 1 Agricultural and Horticultural Science (90158) 2009 — page 4 of 5
soil, allowing water to drain more freely.
If the soil is between field capacity and
saturation, the poor plant growth may
be due to a lack of soil air for the plant
roots. The lack of air results in poor
respiration by the roots and reduced
nutrient uptake. (E)
Lime can make available plant nutrients
which are present in the soil but not
available to the plant. Applying effluent
will only increase the amount of
nutrients which are locked into the soil
and unavailable to the plant. (J)
Q
Evidence
Achievement
Achievement
with Merit
Achievement
with Excellence
FOUR
(a)
EITHER
Chemical properties:
Earthworms burrow through the soil
and digest soil organic material. (D)
As earthworms digest organic material,
nutrients are released which the plant
can then absorb. (E)
Describes the
effects of
earthworms on
chemical or
physical
properties.
A1
OR
Physical properties:
Earthworms burrow through the soil,
creating tunnels which improve the
aeration of the soil.(D)
Describes the
effects of
earthworms on
chemical or
physical properties
AND
links ideas
towards
explaining how
earthworms affect
plant growth.
M1
Plant roots need adequate air to
respire and release energy for plant
growth. (E)
(b)
(ii)
EITHER
Selected management practice:
Applying fertiliser
This involves adding nutrients to the
soil which the plant can use (D).
Describes what
the management
practice of either
applying fertiliser
or rotating crops
results in.
The nutrients dissolve in the soil water
and are then able to be absorbed by
the plant to be used in chemical plant
processes. (E)
A2
This is the best management practice,
as the tomatoes could have been
absorbing more nutrients than the
compost would have been supplying,
so applying fertiliser will improve the
nutrient status of the soil. With
increased nutrients in the soil,
beneficial micro-organisms will flourish,
which in turn will decompose organic
matter, which will release more
nutrients and hence improve plant
growth. (J)
OR
Links ideas
towards
explaining how
the use of this
management
practice improves
the tomato yield
through improved
chemical and
physical
properties.
M2
Links ideas
towards justifying
how the use of this
management
practice is a better
solution than the
rejected
management
practice in terms
of improving
tomato
growth/yield
through improved
chemical and
physical
properties.
Critical thinking
about soil quality
with regard to
disease presence
or compost not
providing the
right/enough
NCEA Level 1 Agricultural and Horticultural Science (90158) 2009 — page 5 of 5
Selected management practice:
Rotating crops
This involves growing similar groups of
plants in different areas in a cycle
lasting several years. This results in a
reduced build-up of soil-borne
diseases. (D)
nutrients.
E
The freedom from soil-borne diseases
results in a healthier plant with better
growth. (E)
Crop rotation is the best solution, as
the reduced tomato yield may be
caused by soil-borne diseases, which
adding fertiliser will not overcome.
Nutrients are already being added to
the soil in the compost, but the problem
is getting worse, so adding more
nutrients with fertiliser is unlikely to
solve the problem. (J)
Judgement Statement
Achievement
Achievement with Merit
Achievement with Excellence
2 A1
2 A2
1 A1
1 M1
2 M2
2 M1
2 M2
1E
Note: E can be counted back to M2 but each grade can only be counted once.