Which option illustrates a positive feedback example in ecosystems?

• A. Predator-prey regulation stabilizes populations.
• B. Ice-albedo warming amplifies warming.
• C. Soil nutrients become permanently fixed.
• D. Water cycle slows down.

Answer: (B)

Positive feedback happens when a small change triggers processes that push the system further in the same direction, amplifying the initial effect. Ice-albedo warming shows this clearly: as temperatures rise, ice and snow melt, lowering the surface’s albedo (reflectivity). Darker surfaces absorb more sunlight, which increases warming, leading to more melting. That self-reinforcing loop makes warming and ice loss accelerate.

Predator-prey regulation is a negative feedback, because increases in predators reduce prey numbers, which then slows predator growth and allows prey to recover, damping the change rather than amplifying it. Soil nutrients becoming permanently fixed isn’t a feedback loop, and a slower water cycle doesn’t inherently create a self-amplifying cycle in this context.