Draw a biomass pyramid to a stated scale
הוצג| English | משמעות |
|---|---|
| biomass/ˌbaɪəʊˈmæs/ | ביומסה |
| scale/skeɪl/ | קנה מידה |
What would explain this observation?
- Many tiny plants can have more total biomass 生物量 than a few large animals. A biomass pyramid represents mass at each level rather than organism count.
Build the model
- A pyramid of biomass represents relative biomass at successive trophic levels.
- Producers, trophic level 1, form the bottom bar.
- Use the supplied biomass measure, commonly dry mass per unit area, consistently.
- Bars at higher levels are centred above the lower bars, and their widths are proportional to the stated biomass.
- biomass: Mass of biological material measured using the stated method.
- scale 比例尺: A defined relationship between drawn length and represented quantity.
Where should the producer bar be placed?
רמת קושי 1/5 · 100 מטבעות + בונוס קטן בהשלמה הראשונה היום
Producers support every other level, so their bar forms the base of the pyramid; consumers stack above in feeding order. Placing producers at the top inverts the flow of biomass.
Match each technical term to its precise meaning.
רמת קושי 2/5 · 140 מטבעות + בונוס קטן בהשלמה הראשונה היום
Use the definitions to distinguish related quantities and processes.
Choose evidence that can test it
- The pyramid is a diagram of a defined sample or estimate, not the physical shape of an ecosystem.
- Equal bar heights allow width to represent relative amount.
- Biomass and energy are related but are not the same quantity; do not label a kilogram dataset in joules.
- Organism numbers also require different data.
In the lab: Convert all masses into one unit, choose a scale fitting the page and calculate each width. Centre bars, label organisms, trophic levels and units and keep producer placement clear. If one bar is too small to draw accurately, state a scale limitation rather than silently giving it a false width.
Which two habits make the investigation or model in this case more defensible?
רמת קושי 2/5 · 140 מטבעות + בונוס קטן בהשלמה הראשונה היום
Stating the conditions and assumptions lets others repeat the work exactly, and recording the supporting evidence lets them check the conclusion. Hiding disagreeing results removes the evidence that could challenge a wrong conclusion, and one measurement can never establish a wider claim.
Work from known quantities
- Known: supplied biomasses are 600, 120 and 24 kg over the same area.
- At 100 kg per centimetre, widths are 6.0, 1.2 and 0.24 cm.
- Keep a common scale; drawing each bar to a separate convenient scale destroys the quantitative comparison.
Your turn: At a scale of 200 kg per centimetre, find the width for 1,000 kg biomass.
At a scale of 200 kg per centimetre, find the width for 1,000 kg biomass.
רמת קושי 2/5 · 140 מטבעות + בונוס קטן בהשלמה הראשונה היום
The result is 5 cm. Known: scale 200 kg per centimetre; biomass 1,000 kg. Width = biomass / scale = 1,000/200 = 5 cm. Every bar in one pyramid must use the same scale, or the visual comparison breaks.
Check the conclusion and its limits
- Pyramid width does not represent the height of an organism.
- More individuals does not always mean greater biomass.
- Masses from different habitat areas need comparable per-area units before being placed in one pyramid.
Not true: A biomass pyramid represents organism count regardless of mass. A BIOMASS pyramid shows mass, so one large tree can outweigh thousands of aphids. Count pyramids can look inverted where biomass pyramids cannot - mass and number are different measures.
- A pyramid of biomass represents relative biomass at successive trophic levels.
- The pyramid is a diagram of a defined sample or estimate, not the physical shape of an ecosystem.
- Watch for: pyramid width does not represent the height of an organism.
A BIOMASS pyramid shows mass, so one large tree can outweigh thousands of aphids.
רמת קושי 1/5 · 100 מטבעות + בונוס קטן בהשלמה הראשונה היום
True. A BIOMASS pyramid shows mass, so one large tree can outweigh thousands of aphids. Count pyramids can look inverted where biomass pyramids cannot - mass and number are different measures.
Mass of biological material measured using the stated method: write the technical term.
רמת קושי 1/5 · 100 מטבעות + בונוס קטן בהשלמה הראשונה היום
biomass means Mass of biological material measured using the stated method.