Question

Grazing by large mammalian herbivores can have a strong influence on ecosystem structure, and can cause ecosystems to transition between alternative states over decades. Which one of the following transitions can result from grazing?

• A. Mangrove to coral reef
• B. Terai grassland to alpine meadow
• C. Savanna to grassland
• D. Tropical rainforest to arid desert

Hint:

Grazing by large herbivores can shift ecosystems from woody, tree-dominated areas (like savannas) to grass-dominated systems.

Answer 1

The Correct Option is C

Grazing by large herbivores can affect the plant composition and structure of ecosystems, often leading to a shift in vegetation types. These shifts are typically from more closed-canopy systems to more open, grass-dominated systems.

Step 1: Analyzing the options.
- (A) Mangrove to coral reef: Grazing does not cause this transition, as mangroves and coral reefs are fundamentally different ecosystems. - (B) Terai grassland to alpine meadow: Grazing does not typically result in a shift from a grassland to a high-altitude meadow. - (C) Savanna to grassland: Grazing often leads to the transformation of savannas into more open grasslands. This is a well-documented ecological process. - (D) Tropical rainforest to arid desert: This is not a typical result of grazing; rather, deforestation and climatic changes may cause such a transition.

Step 2: Conclusion.
The correct answer is (C) because grazing can reduce tree cover and favor the growth of grasses, leading to the transformation of savannas into grasslands.

Final Answer: (C) Savanna to grassland