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]
Figure: Energy flow in a terr )j;gs q2 xdhr4estr isyjs:pf36vaqb. /x k oa66:p ial ecosystem in kJ $m^{-2}yr^{-1}$
Calculate the percentage flow of net primary productivity (NPP) from producers to tertiary consumers.
A. 0.27%
B. 2.70%
C. 0.10%
D. 1.00%
参考答案: A
本题详细解析:
NPP from producers = la p )j /z99ytmbz4dv5imwi5p g 6je2:7800 (kJ $m^{-2}yr^{-1}$)
Energy received by tertiary consumers (before respiration) = 21(kJ $m^{-2}yr^{-1}$)% flow of energy = ($\frac{21}{7800}$)×100 = 0.27%
Calculation for Option B is not correct.
Assuming a 10% transfer at every stage, the tertiary consumers would receive 0.1%, which is a general assumption but varies from ecosystem to ecosystem (Option C).
Option D assumes a 10% transfer but the calculation is not correct as it reaches the top of the food chain .
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