What does nutrient recycling refer to?

Nutrient recycling refers to the exchange of elements between living and non-living components of an ecosystem, which is why this choice is accurate. In this process, nutrients are cycled through various forms as they move from the soil into plants, then into herbivores, predators, and finally back into the environment through decomposition and waste. This exchange is essential for maintaining ecosystem health, as it ensures that essential elements like carbon, nitrogen, and phosphorus are reused and made available again for living organisms.

The other options focus on different ecological concepts: the transfer of energy relates to food webs and trophic levels, breaking down organic matter is a specific process that contributes to nutrient recycling, and ecological succession describes the gradual process of change and development in an ecosystem over time. While all these concepts are interconnected within ecosystems, the specific definition of nutrient recycling as an exchange of elements is what makes this choice the correct one.