Earth resources · Ressources terrestres
| English | Français |
|---|---|
| water cycle/ˈwɔːtə ˈsaɪkl/ | cycle de l'eau |
| rock cycle/rɒk ˈsaɪkl/ | cycle des roches |
| igneous/ˈɪɡnɪəs/ | igneux |
| sedimentary/ˌsedɪˈmentəri/ | sédimentaires |
| metamorphic/ˌmetəˈmɔːfɪk/ | métamorphiques |
| renewable/rɪˈnjuːəbl/ | renouvelable |
| non-renewable/nɒn rɪˈnjuːəbl/ | non-renouvelable |
A water cycle does not balance every pond
- An invented pond receives 30 m³ over a stated period, loses 18 m³ through its outlet and 7 m³ by evaporation. With no other inputs or losses in this simplified model, storage increases by 5 m³.
- A water cycle 水循环 moves water through evaporation, condensation, precipitation, runoff, infiltration and groundwater. Water crossing a pond's boundary can change its local storage.
Which statement fits the simplified local pond water cycle and budget?
The pond is open to inflow, rainfall, outlet loss and evaporation. A local budget does not prove exact constancy for all water on Earth.
Write the local budget before recommending use
- Storage change follows $\Delta S=\text{inputs}-\text{losses}$. Here, $\Delta S=30-18-7=5\ \text{m}^3$; this is a change, not the pond's total volume.
- Proposed extra extraction of 12 m³ gives $\Delta S=30-18-7-12=-7\ \text{m}^3$. Without starting storage and other constraints, the record cannot say whether the pond would empty.
Inputs are 30 m³, outlet loss 18 m³ and evaporation 7 m³. What is storage change in m³?
ΔS = 30 - 18 - 7 = 5 m³.
Under the same budget, add extraction of 12 m³. What is storage change in m³?
ΔS = 30 - 18 - 7 - 12 = -7 m³; this does not specify starting storage.
Distinguish rock-formation processes
- In the rock cycle 岩石循环, igneous 火成岩 rock forms when molten material cools and solidifies. Sedimentary 沉积岩 rock can form when deposited sediment becomes consolidated through compaction and cementation; some forms have other deposition routes.
- Metamorphic 变质岩 rock forms when existing rock changes under heat and pressure without melting. If it melts, later cooling can form igneous rock; not every rock follows one compulsory sequence.
Match each rock type to how it forms.
Formation processes provide different routes. The rock cycle is not one compulsory sequence for every rock, and a photograph alone does not establish exact age.
A rock that fully melts and then cools into a solid has formed metamorphic rock by that melting process.
False: crystallisation from molten material forms igneous rock; metamorphic change occurs without melting.
Compare replenishment with use
- A renewable 可再生 resource can replenish on a relevant timescale; a non-renewable 不可再生 resource does not replenish fast enough relative to human use. Renewable does not mean unlimited.
- A forest producing 100 units of new wood while 130 units are harvested loses 30 units under this simplified budget. Regrowth potential alone does not make that harvest sustainable.
A forest is harvested faster than regrowth replaces it. Which interpretation is supported?
Compare use and replenishment over a stated period. Renewable potential does not guarantee sustainable use or approval.
Fossil fuels are non-renewable because the process that forms them has stopped.
Formation and replacement are too slow relative to human use. Non-renewable does not mean no related geological process occurs.
Keep availability separate from safety and age
- Reeds at a pond do not establish drinking-water safety. A water-volume budget cannot replace measurements relevant to water quality or ecosystem requirements.
- A rock photograph can show features, but does not establish every rock's identity or exact age. Cite the actual measurements, maps, methods and dates used for a conclusion.
Use the supplied record for analysis. A calculated increase in storage does not give permission to extract water or establish long-term sustainable use.
Conserve useful resources, not only atoms
- Matter conservation does not guarantee that material remains concentrated, accessible or useful. Disposal can scatter or mix material, making recovery harder and more energy-demanding.
- Report the boundary, period, starting information and assumptions. Keep rock formation, local water storage and resource-use decisions as related but distinct questions.
A cycle describes processes; a budget tracks a defined stock. Replenishment, usable supply, safety and approval each need relevant evidence.
In one sentence, explain why recycling matters even though matter is conserved.
Example: “Matter can remain present but dispersed or mixed, making useful recovery more difficult.” A conservation statement does not guarantee local availability or unlimited usable supply.