本题目来源于试卷: IB ESS Unit 2: Ecosystems & Ecology，类别为 IB环境系统与社会
[单选题]
An experiment was car gf8 fdf5;op+vb5 *4quat kn7rried out 4glqmchzef,f:1 4 1u z using bottles with an Elodea plant in water. One was kept in light and the other in darkness. The dissolved oxygen values were obtained at the beginning of the experiment and after two days l4z11ug: ,4fhm qczfein both bottles.
What is GPP ;NPP and R?
A. 800 ; 400 ; 400
B. 600 ; 200 ; 400
C. 600 ;400 ; 200
D. 800 ;200 ; 200
参考答案: B
本题详细解析:
GPP = bottle in light (oxygen value) mbv r*dx4w7c -cq c7l6– bottle in the dark
GPP = 800 -200
= 600
Respiration = initial value – bottle in the dark
= 600 – 200
= 400
NPP = GPP – R
= 600 – 400
= 200
The values represent oxygen released during photosynthesis causing an increase in value in the bottle kept in the light.
AND
In the dark, the plant carries out respiration so there is a decrease in value of oxygen.
Values for options A, C and D do not match the calculated values.
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