Which statement accurately describes the potential effects of disturbance on species diversity?

• A. Disturbance has no effect on species diversity in ecological communities.
• B. High levels of disturbance always lead to the highest species diversity.
• C. Low levels of disturbance typically result in the greatest species diversity.
• D. Moderate levels of disturbance can increase species diversity by preventing competitive exclusion.

Answer: (D)

Verified step by step guidance

1. Understand the concept of disturbance in ecological communities: Disturbance refers to events that disrupt ecosystems, such as natural disasters, human activities, or changes in environmental conditions. These events can affect species diversity by altering the balance of competition and resource availability.
2. Learn about the Intermediate Disturbance Hypothesis: This hypothesis suggests that moderate levels of disturbance can promote higher species diversity. At low disturbance levels, competitive exclusion may occur, where dominant species outcompete others, reducing diversity. At high disturbance levels, many species may be unable to survive, also reducing diversity.
3. Analyze why moderate disturbance prevents competitive exclusion: Moderate disturbance creates opportunities for less competitive species to establish themselves by periodically disrupting the dominance of stronger competitors. This balance allows coexistence and increases overall species diversity.
4. Compare the effects of low, moderate, and high disturbance levels: Low disturbance levels often lead to reduced diversity due to competitive exclusion. High disturbance levels can lead to reduced diversity because many species cannot tolerate extreme conditions. Moderate disturbance levels strike a balance, fostering coexistence and higher diversity.
5. Conclude that the correct statement is: 'Moderate levels of disturbance can increase species diversity by preventing competitive exclusion,' as it aligns with the Intermediate Disturbance Hypothesis and ecological principles.