which concept is best illustrated by this diagram
{"Image DocumentName": "Which concept is best illustrated by this diagram?", "Image ImageDescription": "The exchange of CO2 and O2 in an ecosystem. The effect of limiting factors in a biome. Cycling of nutrients in a community. Environmental pressures on a population", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}