Intro to Terrestrial Investigations Abiotic and Biotic Factors

Temperature Moisture Wind Light There are five main abiotic factors that affect organisms in terrestrial ecosystems: Temperature Moisture Wind Light

The most complex factor affecting life in terrestrial ecosystems. And of course: SOIL The most complex factor affecting life in terrestrial ecosystems.

Soil is a mixture of four main components: Soil is a loose covering of weathered (broken-down) rock particles enriched with decaying organic matter. Soil is a mixture of four main components: 1. mineral grains from weathered rock

Where do you think the air spaces in soil come from?

3. Water Water in soil comes from rainfall or ground water and is needed by plants and other organisms that live in soil.

4. Organic Material Organic material in soil is made up of decaying plant and animal remains as well as living organisms, including soil bacteria, worms, fungi, roots of plants, and insects. These organisms recycle organic compounds and nutrients.

Layers of Soil A soil profile is a series of horizontal layers in soil that differ in chemical make-up, physical properties, particle size, and amount of organic matter.

Surface Litter: composed of loose, fallen leaves and organic matter that is only partially decomposed. Topsoil: dark-coloured layer with large amounts of organic matter mixed with minerals Subsoil: contains less organic matter and fewer organisms than topsoil; accumulates nutrients leached from topsoil

Rock particles: contains no organic matter; chemical content of materials in this layer helps determine the pH of soil Bedrock: solid layer of rock

Soil Properties: Texture (an observation we will make in the field tomorrow!) Soil texture is determined by the size of the mineral particles in the soil.

Soil texture depends on the percentage of clay, silt, and sand particles in the soil. A loam soil has the best texture for most crops.

(another test we will be doing tomorrow) Soil Properties: pH (another test we will be doing tomorrow) pH measures how acidic or basic a substance is. The pH of soil depends on the amount of rainfall and the amount of organic material the soil contains. Most plants grow well in soil with a pH between 6 and 7, although some plants, such as blueberries and potatoes, grow well in more acidic soil.

High annual rainfall makes soil more acidic. The rainwater dissolves and removes minerals from soil, leaving more acidic material behind. Dissolves and removes minerals from soil such as calcium, magnesium, and potassium.

Soil pH is important because: - It affects how easily nutrients can be removed from the soil, which affects the type of plants that will grow. - The type of plants then determine the amount of organic matter that farmers have to add to the soil

Native vs. Invasive Plants

Native plant: a plant that has been growing naturally in an ecosystem without any action, past or present, from humans.

Saskatchewan Native Plants Saskatchewan is part of the Grasslands biome. Therefore Saskatchewan native plants would include lots of?

Invasive Plant: a plant which grows aggressively, spreads, and displaces other plants.

What to bring to the Qu’Appelle Valley: Water Snacks Dress in layers (it’s supposed to be 29⁰C) A hat Supportive/good shoes BUG SPRAY! pencil/pen (writing utensil) Device for taking pictures (camera/phone) sunscreen Smiles and a cooperative attitude 