CARBON CALCULATORS AS A TOOL FOR ASSESSING GREENHOUSE GASES EMISSION FROM LIVESTOCK
Carbon calculators – programs for calculating greenhouse gas emissions (carbon footprint) from agricultural production on a scale of a farm. They were created on the base of IPCC methods but don’t used in Russia yet. The purpose of the study was to analyze the effectiveness of their application to assess emissions from livestock and develop recommendations for its reduction. Four of the most common calculators were selected as the objects of the research: Cool Farm Tool, AgRE Calc, Farm Carbon Calculator and Ex-Act. Among them, the Cool Farm Tool was recognized as the most convenient and effective. AgRE Calc and Farm Carbon Calculator do not fully represent the technological features of animal rearing. The Ex-Act is not suitable for the livestock sector because it is based on land use change. According to machine experiments, the most efficient type of farming in terms of reducing greenhouse gas emissions is full grazing, in which manure remains in the fields, and there is no expenditure on the production of additional feed. In this case, the emission is reduced for cows by 2.45 and for horses – by 0.84 t CO2-eq. /head year (Cool Farm Tool); as well as for cows by 0.53 and for horses by 0.42 t СО2-eq./head-year (Farm Carbon Calculator). But this leads to extensive farm management. The second variant is changing of a diet, including expenditure on the feed production. Elimination of green feed from the diet at stable keeping will reduce emissions by 0.05 (AgRE-Calc) – 0.14 (Cool Farm Tool) t CO2-eq/head-year, and the exclusion of silage will lead to a decrease of 0.96 tons of CO2-eq./head-year. But such decisions may lead to decreasing of nutrient balance of diet. To reduce greenhouse gas emission from livestock it may be recommended to reduce number of domestic animals gradually. Farm Carbon Calculator, AgRE-Calc and Ex-Act significantly overestimate an intensity of greenhouse gas sequestration by forests. Due to the discrepancy in estimates between calculators they must be used comprehensively.