Lrm

Question 1

How is soil texture determined?

Answer 1

Soil texture is determined by the size of the particles that make up the soil (this includes organic material)

Question 2

What is a catena or toposequence?

Answer 2

A catena/toposequence is the sequence of soil types down a slope

Question 3

How does soil colour and texture as well as the presence of rocks in a soil profile impact plant root growth and function?

Answer 3

If plants are to grow to their full potential, the soil must provide satisfactory conditions. Loose, rocky well drained soils will inhibit the plant’s ability to trap and absorb water and nutrients and dry the roots out, where as dense, clay, poorly drained soils do not remove water readily and prevent the roots from draining, allowing rot to set in and allowing salts to rise from the lower soil

Question 4

Define the way sedimentary, metamorphic and igneous rocks are formed.

Answer 4

Sedimentary- silt, sand and organic mater compressed to form a solid rock (e.g sandstone)
Igneous- formed from molten rock forced to the surface by tectonic plates through a volcano (e.g granite)
Metamorphic- the physical or chemical change of one rock type to another (e.g Quartz and marble)

Question 5

Provide examples of common types of sedimentary, metamorphic and igneous rocks and describe the conditions in which they were formed

Answer 5

Igneous- granite, basalt: formed through the cooling of volcanic rocks in the earth.
Sedimentary- sandstone, limestone: compaction which occurs when sediments are squeezed together and cementation occurs when dissolved minerals solidify in between cracks of sediment
Metamorphic- marble, quartz: formed from igneous/sedimentary rocks through immense heat and pressure

Question 6

What are common types of rocks encountered within 50km of dookie?

Answer 6

Salurian: college side
Cambrian: town side
Sedimentary mudstone, siltstone and sandstone
Igneous granite and basalt

Question 7

How do the types of rock influence the type of soil in the dookie district?

Answer 7

The parent material influences the nature of the soil in terms of its ability to drain, retain moisture, hold nutrients and stay aerated. For example, the parent material, mt major, is low in iron and magnesium, acidic and prone to salinity, thereby reducing its agriculture capabilities.

Question 8

What factors contribute to the formation of soil from rock

Answer 8

Erosion, bacteria and organic matter, type of parent material, climate

Question 9

How can the age of rocks be determined

Answer 9

Radio carbon dating, fossils, luminescent dating

Question 10

What is the approximate age of the rocks on dookie campus

Answer 10

Between 560 and 420 million years

Question 11

What environmental and agrinomic conditions contribute to soil acidification?

Answer 11

Nitrogen based fertilisers and the natural negative charge of the clay rejects the nitrates

Question 12

What corrective measures can be applied to increase pH?

Answer 12

Lime and nitrogen

Question 13

What is soil sodicity?

Answer 13

Measure of the amount of sodium in the soil

Question 14

What corrective measures can be applied to counter soil sodicity

Answer 14

Increase in organic matter, gypsum, calcium sulphate

Question 15

What are the most prevelant pests and how can they be controlled?

Answer 15

• rabbits
• foxes
• deer
• pigs
• kangaroos
• feral cats and dogs

Control: trapping and culling as well as fencing off areas

Question 16

What is a pest plant

Answer 16

A plant that is detrimental to humans or human concerns e.g Patersons curse, weeping willow, serrated tussock

Question 17

How do pest plants threaten agricultural productivity?

Answer 17

Occupy space used for farmland and overwhelm native and agricultural plants

Question 18

What control measures are available to control pest plants?

Answer 18

Poisoning, volunteer and council run work groups

Question 19

What is a water budget?

Answer 19

An indication of how much water needed for use based requirement, rainfall and evaporation.

Question 20

What is EC and how is it measured

Answer 20

Electrical conductivity, a Measure of salinity measures in EC units

Remember TDS= total dissolved salts

Question 21

How is a catchment defined?

Answer 21

A body of land with a boundary where all the water flows to a central point.

Question 22

How is a soil profile described and how are the layers which comprise a profile defined?

Answer 22

A soil profile is a vertical section of soil that travels downwards showing all the different horizons (A,B and C) that comprise it. The “A” horizon consists of the most nutrient rich layer and contains the majority of plant roots. The “B” horizon is formed by weathering of the underlying rock or via translocation of material, it generally is used to identify the type and origin of the soil and has the properties of both A and C horizons. The “C” horizon is comprised largely of the parent material with very little alteration.