Question

Erie, U.S., is the shallowest of the Great Lakes. The shallowness allows enhanced algae and plant growth. This algae and plant growth are:

Option 1: A biotic factor that keeps salinity at the right levels
Option 2: A biotic factor that impacts food chains and trophic levels
Option 3: An abiotic factor that helps keep species in check
Option 4: An abiotic factor that keeps waters fairly warm

Answer 1

The correct answer is Option 2: algae and plant growth due to Lake Erie's shallowness is a biotic factor that impacts food chains and trophic levels by providing the base for the aquatic ecosystem, impacting light penetration, and affecting oxygen levels when they die and decompose.

Step-by-step explanation:

The algae and plant growth in Lake Erie, due to its shallowness, represents a biotic factor that impacts food chains and trophic levels. Algae and plants are living entities that form the base of aquatic ecosystems, providing food and oxygen for other organisms.

Algal blooms, which are a result of excess nitrogen and phosphorus, can lead to a reduction in light penetration, creating aphotic conditions that are detrimental to photosynthetic plants. Additionally, when algae die and decompose, they can cause severe oxygen depletion in the water, negatively impacting fish and other oxygen-requiring organisms and potentially leading to dead zones. Therefore, Option 2 is the correct answer to the student's question, as the biotic factors influence the ecological structure and function within the lake.