CAP’2ER® “équins”: an environmental footprint calculator tested on 39 French equine systems

International audienceThe agricultural sector is developing new tools to enhance knowledge about livestock activities consequences on climate change. The first environmental impact calculator for equine structures in France, CAP’2ER ‘équins’, has been created to help farmers better evaluate and manage environmental impacts of their activities. CAP’2ER has already existed for ruminant farming. It measures four impacts: climate change, air acidification, eutrophication and fossil energy consumption. Moreover, it quantifies three positive contributions: carbon storage, maintenance of biodiversity and nutritional performance. The tool requires 55 technical data collected on the farm and emission factors for each source of greenhouse gas pollution (housing, storage, spreading, grazing and inputs) found in the scientific literature and specific to the equine species. The CAP’2ER is based on algorithms based on IPCC (2019) for animal and farm emissions and the boundaries of the analysis were from cradle to farm gate, according to LCA analysis. In 2021, the tool was tested on a sample of 39 equine structures (30 riding centres and 9 breeding farms), as varied as possible. The estimated emissions were at 1,544 kg CO 2 eq/head on average (57% due to CO 2 , 31% to CH 4 and 12% to N 2 O). The calculated carbon storage was at 1,429 kg CO 2 eq/head on average. Thus, the sample offset its emissions by 93%, with variations depending on the production system. The main emission source is the purchase of cereal grains or processed feeds, fodder and bedding (38% of total emissions) by equestrian establishments, explained by their low food autonomy. A better optimisation of diets by limiting cereals and extending grazing time (thus decreasing the quantity of fodder and bedding), or even by increasing the surfaces in meadows would be some ways to decrease indirect CO 2 emissions. These first estimates depend on parameters that are not widely available in the literature and that require further studies. Research should develop consolidated emission factors that are more adapted to the various equine systems found in France and Europe