Agriculture Pt 2

Question 1

State two advantages of using insecticides and herbicides.

Answer 1

-Can be used anywhere
-An intensive system that can provide high yields

Question 2

What is resistance?

Answer 2

The ability of a living organism to survive when exposed to a toxic chemical (such as a pesticide or herbicide)

Question 3

Explain why resistance can occur quickly within an insect population? (Mention generations, life cycle and short time).

Answer 3

Many insect species have relatively short lifespans, which means that they can experience multiple generations within a single year.

Question 4

What can farmers do to overcome resistance

Answer 4

Farmers apply an increased dose to improve the effect. The best practice for farmers is to use a range of different pesticides so that if resistance starts to build up to one product another product is still likely be toxic to the best.

Question 5

What is an unintended effect of using insecticides and herbicides

Answer 5

Can kill beneficial insects such as bees, which will effect the pollination of plants.

Question 6

What impact does heavy rain have?

Answer 6

Can cause leaching of insecticides and herbicides into rivers and lakes, causing damage to other organisms

Question 7

Why is giving animals antibiotics a problem

Answer 7

The products may be ineffective in controlling diseases, leaving the human population, as well as the livestock, at greater risk of illness or death

Question 8

Explain what eutrophication is

Answer 8

A sequence events starting with enrichment of water by mineral nutrients or organic matter that leads to a reduction in oxygen level in the water and the death of fish and other animals

Question 9

Explain how excess fertiliser application (use) can also impact on plant growth by changing the soil pH

Answer 9

Large quantities can alter the pH of the soil, affecting the organism that love there and, more importantly, impact on a plants ability to take up nutrients

Question 10

Plants take up water through their roots by osmosis. Explain how too much fertiliser affects this process.

Answer 10

Too much fertiliser can can increase the concentration of solutes in te soil solution, causing water to flow out over a field

Question 11

How does excess nutrients affect the growth of plants?

Answer 11

Too much fertiliser can cause excessively lush growth: the plant grows too rapidly and is unable to support itself.

Question 12

impacts of too much irrigation

Answer 12

damaged soil structure and it compacts, death of plant roots which prevents a sufficient amount of oxygen to respire due to water logging

Question 13

What is salinization

Answer 13

added salt into the soil

Question 14

How can over-irrigation prevent soils from being cultivated?

Answer 14

• Excess water can create unnecessary stress on plants, effectively reducing their water intake
• Over-irrigation results in an oxygen disparity near the root zone in the soil.

Question 15

What is desertification and what causes it?

Answer 15

Is the process by which fertile land becomes desert, poor management of the soil can lead to desertification

Question 16

How does Overcultivation damaging soil structure cause soil erosion

Answer 16

Ploughing or digging breaks up large clumps into smaller amounts. the mechanical breakdown of soil means that the smaller particles are easier to move and more vulnerable to erosion

Question 17

How does overgrazing by having too many animals per area of land cause soil erosion

Answer 17

Large numbers of animals within an area will trample down the plants, damaging them in the process. Animal hooves compact the ground, and compaction reduces the number of air spaces in the soil, reducing root growth and further weakening the plants

Question 18

how does Increased wind erosion due to the removal of vegetation cause soil erosion?

Answer 18

makes the soil far more prone to being blown around by the wind.

Question 19

How does Increased water erosion due to poor soil structure and less vegetation cover cause soil erosion?

Answer 19

Water can erode soils in a number of ways.
- Heavy rainfall
- Rainwater run-off
- Gulley erosion

Question 20

what is terracing

Answer 20

the artificial development of flat areas, for growing crops, in a sloping terrain (on a hill side).

Question 21

How does terracing reduce soil erosion?

Answer 21

It helps to prevent the erosion of soil by rainwater on steep slopes

Question 22

what is contour ploughing

Answer 22

when the ridges and troughs from the ploughing run along the contours of the land (around the hillside) rather than up and down. Each plough furrow (trough) holds water back and prevents large amounts of water rushing down the slope and carrying topsoil with it.

Question 23

what are bunds

Answer 23

artificial banks of soil (embankment) on the edge of a growing space designed to hold back water and preventing soil erosion from run-off. Especially useful for crops such as rice that need to be submerged or require moist soils.

Question 24

what are windbreaks

Answer 24

a barrier to reduce wind erosion, made from living vegetation (hedge) or artificial screen.

Question 25

trickle drip irrigation

Answer 25

delivers water to the base of the plants using small pipes.
The sustainable benefits are minimising the amount of water used, the ability to only use the system when the plants need water, automation of the process to reduce the amount of labour needed to operate it, and a reduced risk of salinization of the water in the soil because less water evaporates from the soil surface and therefore salts are not drawn up from deeper in the soil.

Question 26

what is rainwater harvesting

Answer 26

Rainwater harvesting is the collection of water from the roofs of buildings and hard surfaces and stored in tanks or reservoirs for later use. Suitable for irrigation as water for plants does not need to be as clean as potable (drinking water) and water supplied to livestock.