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Calculate daily nitrogen excretion

Source: R/core_model_nitrogen_balance.R
calc_nitrogen_excretion.Rd

Calculates daily nitrogen excretion per animal (kg N/head/day) as the difference between nitrogen intake and nitrogen retention.

Usage

calc_nitrogen_excretion(species_short, nitrogen_intake, nitrogen_retention)

Arguments

species_short

Character. Code identifying the livestock species. Supported values include:

  • PGS: pigs

  • CML: camels

  • CTL: cattle

  • BFL: buffalo

  • SHP: sheep

  • GTS: goats

nitrogen_intake

Numeric. Daily nitrogen intake (kg N/head/day).

nitrogen_retention

Numeric. Daily nitrogen retention in animal body tissues and products (e.g., growth, pregnancy, milk...) (kg N/head/day).

Value

Numeric. Daily nitrogen excretion (kg N/head/day).

Details

Nitrogen excretion represents the fraction of consumed nitrogen that is not retained in animal tissues or products and is therefore excreted in urine and dung.

Nitrogen excretion is calculated as:

\(nitrogen\_excretion = nitrogen\_intake - nitrogen\_retention\)

where all quantities are expressed in kg N/head/day.

This quantity forms the basis for subsequent calculations of nitrous oxide (N2O) emissions from manure management under the IPCC Tier 2 methodology.

References

IPCC. (2019). 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Chapter 10: Emissions from Livestock and Manure Management. Equation 10.31A.

This function is part of the run_nitrogen_balance_module().

See also

run_nitrogen_balance_module, calc_nitrogen_retention