What is a closed field system?

A closed field system is an agricultural or ecological system where the inputs and outputs are controlled and minimized, creating a self-sustaining environment. This system aims to recycle resources, such as nutrients and water, reducing reliance on external inputs and minimizing waste. Closed field systems are often utilized in practices like hydroponics and aquaponics, where plants are grown without soil in a controlled environment. By maintaining a closed loop, these systems can enhance efficiency and sustainability in food production.