Soil Formation and Importance in Agriculture

Questions and Answers

What is the process of chemical breaking down of rocks?

Weathering

What is the parent material of peat?

Remains of dead plants and animals

Which type of rock is formed from the cooling of magma below ground?

granite

What is the name of the type of soil formed in bogs?

Peat Signup and view all the answers

What is the process by which sedimentary rocks are formed?

erosion and deposition Signup and view all the answers

What is the result of freeze-thaw action on rocks?

Physical breakdown of rocks Signup and view all the answers

What is the name of the metamorphic rock formed from limestone?

Marble Signup and view all the answers

What is the primary mineral composition of limestone?

calcium carbonate Signup and view all the answers

What is the name of the igneous rock that is commonly found in areas of volcanic activity?

Basalt Signup and view all the answers

What is the name of the sedimentary rock formed from sand-sized grains?

Sandstone Signup and view all the answers

What is the name of the metamorphic rock formed from shale?

Slate Signup and view all the answers

What are the three main characteristics that are used to describe soil?

Soil texture, pH, and drainage are the three main characteristics used to describe soil. Signup and view all the answers

What is the main difference between young soil and old soil in terms of fertility?

Young soil gets its fertility from rock minerals and organic matter, while old soil gets its fertility mainly from organic matter. Signup and view all the answers

What is the role of forests in terms of soil nutrient holding capacity?

Forests have a high nutrient holding capacity due to the ability of trees to hold nutrients in the soil. Signup and view all the answers

What is the main factor that affects soil formation in terms of topography?

Topography, as shown in the diagram, affects soil formation through soil erosion. Signup and view all the answers

How does the availability of parent material affect soil formation?

Young soil has high levels of parent material available for soil formation, while old soil has limited availability of parent material. Signup and view all the answers

What is the main difference between grassland and forest ecosystems in terms of soil characteristics?

Grasslands have a lower nutrient holding capacity compared to forests, which have a higher capacity. Signup and view all the answers

What is the effect of soil erosion on soil fertility?

Soil erosion reduces soil fertility by removing the top layer of soil, which is rich in nutrients and organic matter. Signup and view all the answers

Study Notes

Soil Formation

Soil is the top layer of the earth's surface, composed of weathered rock.
Soil is important in agriculture for:
- Plant growth and development
- Water storage and filtration
- Carbon sequestration
- Support for biodiversity

Soils in Ireland

Irish soils are considered young, formed from glacial drift after the last ice age (approximately 1000 years ago).
Glaciation is the alteration of the earth's surface by a glacier through erosion and deposition.

Parent Rock

Parent rock can be:
- Igneous (formed from magma): granite (slow cooling, large crystals), basalt (fast cooling, small crystals)
- Sedimentary (formed from sediments): sandstone, shale, limestone
- Metamorphic (formed from transformed rocks): quartzite, gneiss, slate, greenstone, marble

Weathering

Weathering is the chemical breaking down of rocks into smaller particles.
Types of weathering include:
- Freeze-thaw action
- Chemical weathering

Organic Parent Material - Peat/Bog

Peat is a type of soil formed from the remains of dead plants and animals in bogs.
Peat's parent material is not fully decomposed due to:
- Low oxygen levels
- Acidic conditions
- Cool temperatures

Soil Characteristics

Soil texture, pH, and drainage are determined by:
- Parent material
- Topography
- Vegetation
Soil fertility comes from:
- Rock minerals (young soil)
- Organic matter (old soil)