Carbon is in a constant state of movement from place to place. It is stored in what are known as reservoirs, and it moves between these reservoirs through a variety of processes, including photosynthesis, burning fossil fuels, and simply releasing breath from the lungs. In ecosystems, matter and energy are transferred from one form to another. Matter refers to all of the living and nonliving things in that environment. Nutrients and living matter are passed from producers to consumers, and then broken down by decomposers. Decomposers break down dead plant and animal matter.