A grassland ecosystem fixes 20,000 kJ/m²/yr as net primary productivity. With ~10% trophic transfer between levels, how much energy reaches tertiary consumers (level 4)?
- Acheck_circle
20 kJ/m²/yr (10⁻³ × NPP)
- B
2000 kJ/m²/yr (10⁻¹ × NPP)
- C
200 kJ/m²/yr (10⁻² × NPP)
- D
2 kJ/m²/yr (10⁻⁴ × NPP)
Explanation
Producers → primary → secondary → tertiary requires three transfers at 10% each: 20000 × 0.1³ = 20000 × 0.001 = 20 kJ.