Biomass Calculator
Calculate biomass of a population or ecosystem component. Convert between biomass, density, and energy content. Estimate standing crop biomass from population data.
🌿 Ecology📐 Biomass = N × average mass🧬 Biology
Population size N (individuals)
Average mass per individual (g)
Energy content (kJ/g, optional)
Please enter valid values.
Formula & Reference
| Variable | Symbol | Formula | Units |
|---|---|---|---|
| Biomass Calculator | — | Biomass = N × average mass | g or kg |
Step-by-Step Examples
Example 1
Grass Biomass
500 grass plants, average 250 g each.
- Biomass = 500 x 250 = 125,000 g
- = 125 kg standing crop biomass
✓ 125 kg total biomass
Example 2
Zooplankton
1x10^6 copepods, 0.002 mg each.
- Biomass = 1e6 x 0.002 mg = 2000 mg
- = 2.0 g/m³ (if in 1 m³ water)
✓ 2.0 g total
Example 3
Tree Stand
200 trees, average 500 kg each, 20 kJ/g energy content.
- Biomass = 200 x 500,000 g = 10^8 g = 100 tonnes
- Energy = 10^8 x 20 kJ = 2x10^9 kJ
✓ 100 tonnes biomass, 2x10^9 kJ energy
Real-World Applications
Carbon Accounting
Biomass data used to estimate carbon stored in forests for climate models and carbon credits.
Fisheries Management
Fish biomass estimates determine sustainable harvest levels.
Ecosystem Ecology
Biomass pyramids show energy stored at each trophic level.
Bioenergy
Biomass energy content determines potential for biofuel production.
Common Mistakes to Avoid
⚠️
Dry vs wet biomass
Dry biomass (oven-dried) is the standard in ecology. Wet biomass includes water, which varies seasonally. Always specify which is used.
⚠️
Area-based biomass
Biomass often expressed per unit area (g/m²) or volume (g/m³). Divide total biomass by sampled area to get density.
⚠️
Net vs gross primary production
Standing biomass at one time is not the same as production (biomass added over time). Biomass can be stable while production is high if consumption is also high.
Frequently Asked Questions
What is biomass in ecology? ▾
The total mass of living organisms in a defined area or population. Expressed in grams, kilograms, or tonnes. Dry weight biomass is the standard for cross-site comparisons.
What is the biomass pyramid? ▾
A diagram showing biomass at each trophic level. Typically: producers > herbivores > carnivores. Inverted in some aquatic systems where phytoplankton turnover is very fast.
What is primary productivity? ▾
Rate of biomass production by autotrophs (plants, algae). Gross primary production (GPP) = total photosynthesis. Net primary production (NPP) = GPP - respiration.
How does biomass relate to carbon? ▾
Plant biomass is approximately 50% carbon by dry weight. 1 kg plant dry biomass ≈ 0.5 kg carbon. Used to convert biomass measurements to carbon stocks.
What is standing crop? ▾
The total biomass present in an ecosystem at one moment. Different from production, which measures change in biomass over time.