Question

Leader name 2. Biosphere 2 is a research facility designed to be an artificial, closed ecosystem. The closed nature of the biosphere allows relatively precise monitoring of various factors like gasses and other ecosystem processes. The graph shows the amount of carbon dioxide in Biosphere 2 over a typical 24 hour period. a. What is the relationship between 1000 the time of day and the amount of 2 carbon dioxide in the research facility? Why? b. Why do CO, levels rise at night rather than just remaining at a flat line after 4pm? Carbon dioxide (parts per million) 12am 4:00 8:00 400 8:00 am 200 noon Time of day

Answer 1

Wild fires. roo Respirato Pop & Decomposition Waste ta Dead . organisms. . When we think of carbon dioxide in Earth's atmosphere, we tend to presume that it is constantly on the crise. I For instance, on local scales more carbon dioxide is present at night than during the day and on continental scales, there is more in winter than in summer . -> monitored by Copernicus Atmosphere Monitoring services CCAMS) to help scientists improve their understanding of the carbon cycle. h During the day , plants take up more com through photo synthesis than they release through respiration & so concentrations of carbon - dioxide in the air decrease. to carbon-fixation

Then at night plants vreduce or even slop photosynthesising, vreleasing carbon dionide back into the air. This is often called' natural carbon cyclo When sunlight is available plants diave the energy to photosynthesise, absorbing co, and water and turning it into glucose for the plant and oxygen that is released into the atmosphere. Plants use the glucose to build darger molecules, so they can for instance grow, but also to fuel the cells, just as we humans do. They also respine, using oxygen to buen glucose and releasing carbon dioxide . This absorption and release of coz happens all the time. Remaining flat means coa co released at a constant rate while in the graph given it crises slowly and gradually increases. Gradual increase means that plant respiration is more than photosynthesis. This is more because recently latent reduction of photosynthetic capacity can begin in the early morning e preceding the midday depression "Diwrnal changes of the photo synthetic light cresponse curve and incident sunlight intensity were measured under field conditions or

(1) light saturated photosynthete decreased beginning at sunrise 1 (2) the incident sunlight intousity leaves increased from sunrise (3 combining (1) and (2). het photosynthetic crate under material sunlight intensity increased from sunrise, reached a maximum at mid-morning, then show midday depression in house Son Results - photosynthetic preceding the the latent morning reduction of capacity begins at sunrise apparent midday depression, 1200 4 mid-day орлим. (photosynthesis) 906600 latent 00 morning reduction (photosynthesis) Lam 4am 8 am 12. 4pm 8pm 12 am hoon