Objective 1/8/2013 Explain how soil is formed through erosional processes. Intro Weekly WS #18 What do you think soil is?

Soil Formation

Soil Formation Soil Loose mixture of rock fragments, organic material, water, and air that can support the growth of vegetation Different soils have different textures and color

Soil Formation How does soil form? As rock breaks down, plants and animals are able to live in it. As plants and animals die, their decomposed parts add to the soil, making it more livable for others!

Soil formation Importance of soil Soil is where the lowest energy levels of plants and animals live. Without it, we could not survive, either!

Soil What are the properties of soil? Soil consists of 4 Horizons Horizon O (topsoil) - organic material; the darker the soil, the higher the nutrient content Horizon A - where plants and most animals live; the more organic matter the more fertile Horizon B (subsoil) - where there are more clays and broken up rock Horizon C - made of partially weathered rock Bedrock – layer of rock beneath the soil

Soil Are all soils the same? No; climate and bedrock have a huge impact on what type of soil forms! Tropical soil is thin cause of heavy rains Desert soil can be toxic cause of evaporation Temperate soil is just right, producing fertile crops

Soil Formation Summary: What is soil? Why is it important? What are the four horizons? Describe each. Which type of soil is best for growing crops?

Outro Pick two types of soil and create a Double-Bubble map for them!