Lesson 1.2: Biotic Factors: The Influence of Living Things
Completion requirements
Lesson 1.2: Biotic Factors: The Influence of Living Things
In this lesson, you will study what influence living things have on an ecosystem. The context for this will be the prairie grassland. First Nations perspectives play a vital role in this lesson.- Read pages 413 to 419 of the textbook, ending at the investigation. Answer the questions as you encounter them.
Check your answers with those in the “Practice Answers” in the online course.
When you think of a predator, such as a hawk, you think of a creature that destroys or devours. Naturally, you would expect that an increase in the hawk population would reduce the population of the prairie dog—its prey. Maybe what’s not so clear is the effect that a change in a prey population has on its predator population. As you will discover in the next investigation, Hudson’s Bay Company fur-trading records show that predator populations and prey populations are interrelated.
Which do you think has the greatest biomass; a hectare of Prairie or a hectare of Boreal Forest? Prairie ecosystems have the largest biomass. 75% - 80% of the biomass is underground. Prairie dogs are a key prairie species because they dig deep into hard, nutrient rich clay and carry to the surface. This rich, aerated clay provides vital nutrients to the plants around prairie-dog towns which are used by a many species of animals.
Bison are one species that benefit from prairie dogs. The vegetation around prairie-dog towns is protein rich, and an important nutrient sources for bulls recovering from the fall rut. In turn, Bison tramp down the soil so that prairie dogs can effectively burrow in it.
Bison are one species that benefit from prairie dogs. The vegetation around prairie-dog towns is protein rich, and an important nutrient sources for bulls recovering from the fall rut. In turn, Bison tramp down the soil so that prairie dogs can effectively burrow in it.
- Read the investigation on pages 419 to 421 of the textbook. Follow the directions, and answer the questions.
Science 20 Textbook. Albert Education
- Read page 421 of the textbook, beginning with “Competition”.
- Read “1.2 Summary” on page 422 of the textbook. Then, complete “1.2 Questions”.
Science 20 Textbook. Albert Education