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]
To increase the reliabili;elnnx3i 4cy2d+x718rhisx t ty of the data, it is impse456oy hl*znortant to take multiple readings of o *h46syez5nlthe same factor.
Identify the factor that would require the most readings to ensure its reliability.
A. Early morning air temperature in a cloud forest in Ecuador in March
B. Particle size of the soil on the savanna in the Serengeti, Tanzania
C. Leaf size of oak trees (Quercus robur) in a city in Germany in June
D. Flow velocity of the Mekong River at the Myanmar, Laos, Thailand tripoint in November
参考答案: C
本题详细解析:
important to take more readings in order to capture the entire rc ; xze:*vnd-yange.
There is great variability amongst organisms within a species, so a large number of readings is necessary to ensure that the data obtained is reliable. Think of young and old trees, trees growing in more favourable circumstances than others, and even leaves within a tree, as some will be newer (and smaller) than others. Option C is correct.
Air temperature (option A) will vary during the day, and flow velocity (option D) will vary in different seasons, but the statements define at which time of day or year they are to be measured, thus limiting the variability.
The soil on the savanna in the Serengeti (option B) is likely to be well-mixed and uniform throughout the ecosystem, thus needing relatively few readings.
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