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 used forj.l:p0hg8 ujl pyra.bzuckwd4((ro8 .tap ai jp-5mids 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 kilocb9dj-r7x0co s z xz)5galories option B) are measures for energy but do not include area and time, which is how productivity is measured in an ecosystem. Option C does incluxjosx5r7c b -zz d09)gde 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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