| system(noun, scheme, unit, interaction) |
| ecology(noun, study, science, system, structure) |
| scheme(noun, system, unit, interaction) |
| complex(noun, system, scheme, unit, interaction) |
| unit(noun, system, scheme, interaction) |
| biology(noun, study, science, system, structure) |
| area(noun, system, scheme, unit, interaction) |
| combination(noun, system, scheme, unit, interaction) |
| composite(noun, system, scheme, unit, interaction) |
| environment(noun, study, science, system, structure) |
| group(noun, system, scheme, unit, interaction) |
| nature(noun, study, science, system, structure) |
| region(noun, system, scheme, unit, interaction) |
| ecoregion(noun, concept, area, science, ecology) |
| energy pyramid(noun, expression, concept, science, idea) |
| organization(noun, system, scheme, unit, interaction) |
| atmospheric chemistry(noun, expression, entity, study, science) |
| interaction(noun, system, scheme, unit) |
| interconnectedness(noun, system, scheme, unit, interaction) |
| programming(noun, study, science, system, structure) |