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]
State the units usedm(:dpc tl7b 9i for pyramy l )epk+o /mhw-k70o;fmq2 faids of energy.
A. Calories
B. Kilocalories
C. $KJm^{-2}$
D. $KJm^{-2}y^{-1}$
参考答案: D
本题详细解析:
Calories (option A) and kilocalories option B) are meas-s-hh1 no5 gwydw7 :ld+ hcmi.ures for energy but do not include area and time, which is how prodschoiyd .-5l7n:hm dwg+hw-1uctivity is measured in an ecosystem. Option C does include the area but not the time. To see energy values over a specified time, usually a year, the units $KJm^{-2}y^{-1}$ are used
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