Ecology

Agro-ecology and climate

Climate and veld decide what a farm can grow. Agro-ecology at this grade is matching the enterprise to the rain, the temperature and the grazing.

CAPS

Grade 11 · Agricultural Sciences · Ecology

Agricultural Sciences splits animals from plants, soil and management.

  • The papers

    Paper 1 is animal nutrition, animal production, reproduction and protection. Paper 2 is soil science, plant studies, and agricultural management. Each paper is 150 marks.

  • How to write it

    Use the farming term, then the reason: a deficient mineral, a symptom, a management practice, and why it changes the yield or the health of the animal. A list with no cause does not explain.

  • How a marker reads it

    A common mix-up is one national stocking rate, or planting a winter-rainfall crop in a summer-rainfall district without irrigation.

Data-response questions want you to read the table first. A general paragraph about farming that ignores the numbers scores as if you did not see them.

°C

Diagram

Worked theory

Worked theory. A sourveld camp in a high-rainfall summer area, grazed hard in winter when the grass is unpalatable and not growing. The plants do not recover before the next grazing. A sweetveld camp in a drier area can be grazed more evenly through the year, but it cannot carry the same number of cattle per hectare as a wetter camp. Copying a neighbour’s stocking rate from a different veld is how camps die. The climate sets the calendar. The veld type sets the number of animals.

More worked examples

  • Sourveld in July

    High-rainfall sourveld on the Highveld grows in summer and becomes rank and unpalatable in July. Grazing it hard in July, when it cannot regrow, opens bare ground for the spring storms to cut. Sweeter veld in a drier district stays palatable longer but carries fewer animals per hectare. Copying a neighbour’s 8 cattle per 10 hectares from the wet district onto the dry one is how the dry camp dies in a single winter.

  • Three camps

    A farmer splits the veld into three camps. Cattle graze one while the other two rest, including through flowering so the grasses can seed. After a few weeks the herd moves. The grazed camp is short and then recovers. A single camp grazed all year never flowers and thins out. The rest is the input. Buying more cattle without a camp to rest them on spends the grass the rest was meant to save.

In ordinary words

Summer-rainfall veld, such as the Highveld and the bushveld, carries different grasses from the winter-rainfall fynbos and renosterveld of the Cape. Crops and breeds that fit the rain calendar suffer less. Carrying capacity is how many animals the veld can feed without it thinning out. Overstocking looks like profit until the grass and the soil fail. Fire, in fire-adapted veld, is a tool with a season, not only an accident.

In South Africa

Sweetveld and sourveld, and the summer rain of the interior, are the map behind the herd.

Part 1 / 4

What it is

Climate and veld decide what a farm can grow. Agro-ecology at this grade is matching the enterprise to the rain, the temperature and the grazing.

More worked examples

Board walkthroughs on this topic. Open one, copy the working, then try the next.

Example 1 / 20

A farm's average rainfall is 450 mm per year and it is in a summer-rainfall area. Suggest suitable farming.

How we got there

Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

Explain in another language · 11

1. What is the question asking?

Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: A farm's average rainfall is 450 mm per year and it is in a summer-rainfall area. Suggest suitable farming.

Before any working — hunt first

Given

Numbers and units already in the sentence: 450 mm. Copy each one into a column. A name without a number is not given.

Missing

After you copy the given, the letter that still has no number is missing. The paper is pointing at: Suggest suitable farming. Circle that word — that is the missing variable.

Find

We are required to find: Suggest suitable farming. Write that as a symbol on the left, with a question mark, before you touch a formula.

Calculate

What we need to calculate: Semi-arid. Then substitute the given, one line at a time, to get Suggest suitable farming.

In other words — as if you have never seen this before

If you have never seen this before: Semi-arid. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

2. What do we already know?

450 mm, summer rain.

3. Which method — and why this one?

Semi-arid.

4. Step-by-step working

  1. 01 / 08

    Step A — Read the question twice

    Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

    Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

  2. 02 / 08

    Step A2 — Hunt: Given, Missing, Find, Calculate

    Given: Numbers and units already in the sentence: 450 mm. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Suggest suitable farming. Circle that word — that is the missing variable. Find: We are required to find: Suggest suitable farming. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Semi-arid. Then substitute the given, one line at a time, to get Suggest suitable farming.

    Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

  3. 03 / 08

    Step B — Write the given in a column

    450 mm, summer rain.

    Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

  4. 04 / 08

    Step C — Name the method in words

    Semi-arid.

    Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

  5. 05 / 08

    Explain

    Semi-arid: extensive cattle or sheep farming, drought-tolerant crops such as sorghum; dryland maize is risky.

    Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

  6. 06 / 08

    Step G — Sense-check the size

    Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

    Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

  7. 07 / 08

    Step F — Box the answer with its unit

    Extensive livestock and drought-tolerant crops.

    Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

  8. 08 / 08

    Step H — What the marker is looking for

    On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

    Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

5. The answer

Extensive livestock and drought-tolerant crops.

Copy onto your answer sheet — in this order

Answer: Extensive livestock and drought-tolerant crops.

6. Check it like a marker

Below ~500 mm, dryland cropping is risky.

7. A trap first-timers fall into

First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

Ntsako · fx-991ZA PLUS. Tap to calculate.