A Geographical Profile of Manure Production in Canada

Estimated Fecal Coliform Bacteria Production in Livestock Manure

The main objective of this study was to estimate and map the quantity of livestock manure produced in Canada, and the annual quantity of nitrogen, phosphorus, total coliform bacteria and fecal coliform bacteria found in livestock manure. To estimate these variables, 1996 Census of Agriculture livestock populations by enumeration area were multiplied by daily manure quantity coefficients derived from the 1997 American Society of Agricultural Engineers (ASAE) Manure Production and Characteristics Standard.^[1] Data were aggregated to the sub-sub-basin level, normalized by sub-sub-basin area, and then mapped.

The geographic unit used to present this analysis is the sub-sub drainage basin from Environment Canada's 1986 hydrometric map series.^[2] As stated previously, drainage basins, basins, watersheds, and river basins are synonyms used to describe surface drainage catchment areas.

For the purposes of this research, total manure production consists of feces and urine. Bedding and other types of material such as feathers, unused feed, etc. are not included in these calculations. Nitrogen is represented by Total Kjeldahl Nitrogen (TKN), which consists of total organic and total ammonia nitrogen. However, throughout this document TKN is referred to as "nitrogen". The phosphorus calculations are based on coefficients representing "total phosphorus", but are referred to in this document simply as "phosphorus".

Data quality issues

It is important to stress that these data are estimates. A variety of assumptions have been made.

It is assumed that Canadian livestock of a certain type produce similar amounts of manure and have similar characteristics (e.g. production of nitrogen, phosphorous and bacteria) to the equivalent type of American livestock. The ASAE standards are used because they include the widest range of descriptive variables and are updated on a regular basis, which will allow for longitudinal research. A Canadian source that provides the equivalent information could not be found.

The ASAE standards are calculated from a wide base of published and unpublished information on livestock manure production and characterization. These standards were based on arithmetic averages and actual values vary due to differences in animal diet, age, usage, productivity and management.

Several variables in the ASAE standards were missing specific coefficients for specific livestock. Coefficients were derived from a similar species' weight and characteristics. For example, an average of layer, broiler, turkey and duck coefficients was used for the category "other poultry". Coefficients for pullets did not exist, thus the broiler coefficients were used, since pullets are similar species and similar in age. These modifications are considered minor.

Due to data limitations, for the purposes of this study, total livestock was comprised of dairy cows, beef cattle, calves, hogs, horses, sheep, pullets, broilers, layhens, turkeys, and "other poultry". Given that there are other livestock found in Canada, such as buffalo, deer, and rabbits, these numbers under-estimate the actual quantity of manure produced in Canada.

The data used for this research were based on livestock populations as of May 14, 1996, the day the Census was conducted. To provide estimates for the entire year, these census livestock populations were used to calculate manure production for the entire year. Some misrepresentation could occur if actual livestock populations fluctuated significantly over the course of the year.

For more information, please contact Nancy Hofmann, Doug Trant or François Soulard at (613) 951-0297 or environ@statcan.gc.ca.