Chapter 3 Notes Ecosystem Boundaries Biotic and abiotic components of an ecosystem provide the boundaries that separates them from one another Some have a well-defined boundaries: Like a cave Scientist might define a terrestrial ecosystem as the range of a particular species of interest Ecosystems occur in a wide range of sizes Ecosystem Process Each ecosystem interacts with surrounding ecosystems Change in ONE ecosystem can affect the global environment Photosynthesis and Respiration Nearly all of the energy that powers ecosystems comes from the sun Plants, algae and other organisms have the ability to convert the suns solar energy to usable from of energy, these are called producers/autotrophs