Litter Decomposition Rate Calculator

Litter Decomposition Rate Calculator

Leaf litter and other dead organic matter break down roughly exponentially over time - this calculator uses the classic Olson (1963) decomposition model to estimate what fraction of the original litter mass remains after a given period.

Fraction Remaining = e^{(-k × t)}
where k = decomposition constant (per year), t = time in years

Example

Decomposition constant k = 0.5, after 2 years:

Fraction Remaining = e^{(-0.5 x 2)} ≈ 0.368 → 36.8% remaining (63.2% decomposed)

What Drives the Decomposition Constant (k)

The value of k reflects local conditions: moisture availability, temperature, microbial and fungal activity, and the litter's own chemistry (leaf litter high in lignin and low in nitrogen decomposes much more slowly than soft, nitrogen-rich litter). Tropical rainforest litter typically shows a much higher k value than litter in cold or arid climates, which is exactly why cold and dry regions can accumulate thick surface litter layers or even peat over long timescales, while tropical litter is often nearly gone within a year.