What does the term "nutrient cycling" refer to?

The term "nutrient cycling" refers specifically to the exchange of nutrients between organisms and their environment. This concept is essential to understanding how ecosystems function and maintain balance. Nutrient cycling involves the movement and transformation of nutrients like carbon, nitrogen, and phosphorus through different components of an ecosystem, including soil, water, plants, animals, and microorganisms.

By cycling through these systems, nutrients are made available for use by living organisms, which then return them to the environment through processes like decomposition, excretion, and death. This ongoing exchange is vital for sustaining life, promoting biodiversity, and maintaining the health of ecosystems.

The other options do not accurately capture the essence of nutrient cycling: food processing pertains to how food is prepared and preserved; increasing nutrients in foods focuses on enhancing the nutritional content; while the reduction of waste in food production relates to improving efficiency and sustainability in food systems. These concepts are important but distinctly different from the fundamental process of nutrient cycling.