Question

Which of the following factors could be represented mathematically to explain changes in carrying capacity at different ecosystem scales? (Select all that apply)

Responses

Availability of water resources
Availability of water resources

Seasonal changes in temperature
Seasonal changes in temperature

Genetic variation within a species

Genetic variation within a species

Human activities such as deforestation

Answer 1

All of them.

- Availability of water resources — can be quantified (e.g., mm/year, runoff, soil moisture) and used to set or vary K.
- Seasonal changes in temperature — modeled as a periodic function that alters birth/death rates or resource availability, producing a time-varying K(t).
- Genetic variation within a species — can be represented by parameters for growth rate, survival, resource-use efficiency or by multiple genotype classes; these change effective carrying capacity.
- Human activities such as deforestation — represented as changes in habitat area or resource supply (step or trend functions) that reduce K.

In practice these factors are incorporated into population models by making K and demographic rates functions of measurable variables (e.g., K(t) = f(water, temperature, land area, trait distribution)).