The purpose of the study cited was to investigate the association between the economic and environmental facets of sustainability as it relates to milk production in the pasture-based dairy operations of the country.
The data derived from a case study of 62 farms from the Eastern Cape (55), Western Cape (3) and KZN (4) that are following the Trace & Save advisory package for sustainable production. These farms supply almost 10% of the country’s milk. The methodologies used for calculation were based on proposals of the UN’s IPCC.
The results showed that the best of the case study farms in terms of soil carbon levels, carbon footprint and nutrient utilisation, have a comparatively low environmental impact compared to global averages. The soil carbon levels are also well above optimal. Even the medium environmental impact group of the study reflected relatively well compared to global averages.
The statistical analyses showed that soil carbon content and nitrogen fertilizer application rates are negatively correlated. The primary reason is that healthy soils, which have optimal microbial life, fertility and structure, require lower fertilizer inputs to achieve optimal pasture and crop growth. This is due to the provision of nutrients to plants through natural nutrient cycling as supported by a healthy, balanced soil food web system.
The gross margin of each farm was calculated as the total income per litre of milk minus the following variable costs per litre: concentrates, roughage, fertiliser, electricity and fuel (costs such as labour, equipment, infrastructure, veterinarian and medical costs were not included – thus the calculation is not a profit margin). The results showed that one farm increased its gross margin by 43% between 2013 to 2019 by following the Trace & Save system.
The higher margins obtained were associated with a lower carbon footprint and higher nitrogen and phosphorous utilisation, and sustainability was influenced by efficiency of milk production per hectare and per kg live weight, both from an environmental impact and an economic perspective.
An interesting observation was that rainfall did not significantly impact on environmental and economic performance. This implies that geographic location, climate and soil type do not necessarily limit or propel farm sustainability.
The overall conclusion drawn from the study is that implementing sustainable best practices (i.e. CA/RA) should lead to more profitable milk production in pasture-based systems with a lower environmental impact. This is a win-win for farmers, processors, consumers and in the longer term for the dairy industry as a whole.