Nutrient provision capacity of alternative livestock farming systems per area of arable farmland required

M R F Lee,J P Domingues,G A Mcauliffe,T Takahashi,F Accatino,M Tichit

doi:10.1038/s41598-021-93782-9

Abstract

Although climate impacts of ruminant agriculture are a major concern worldwide, using policy instruments to force grazing farms out of the livestock industry may diminish opportunities to produce nutritious food without exacerbating the food-feed competition for fertile and accessible land resources. Here, we present a new set of quantitative evidence to demonstrate that, per unit of overall nutrient value supplied by a given commodity, the demand for land suitable for human-edible crop production is considerably smaller under ruminant systems than monogastric systems, and consistently so at both farm and regional scales. We also demonstrate that imposition of a naïvely designed “red meat tax” has the potential to invite socioeconomic losses far greater than its environmental benefits, due largely to the induced misallocation of resources at the national scale. Our results reiterate the risk inherent in an excessively climate-focused debate on the role of livestock in human society and call for more multidimensional approaches of sustainability assessment to draw better-balanced policy packages.

Highlights

Climate impacts of ruminant agriculture are a major concern worldwide, using policy instruments to force grazing farms out of the livestock industry may diminish opportunities to produce nutritious food without exacerbating the food-feed competition for fertile and accessible land resources
The best available information in today’s scientific literature suggests that, when evaluated in carbon dioxide equivalent emitted per unit of food produced, ruminant systems generally emit higher levels of greenhouse gases (GHG) than monogastric livestock systems as well as systems that produce plant-based protein[7,8,9]
We present new evidence to demonstrate that per unit of nutrient density scores (NDS)[21,22], a measure of the overall nutrient value supplied by a food product, the demand for land suitable for human-edible crop production is considerably smaller under ruminant systems than monogastric systems

Summary

Introduction

Climate impacts of ruminant agriculture are a major concern worldwide, using policy instruments to force grazing farms out of the livestock industry may diminish opportunities to produce nutritious food without exacerbating the food-feed competition for fertile and accessible land resources. The best available information in today’s scientific literature suggests that, when evaluated in carbon dioxide equivalent emitted per unit of food produced, ruminant systems generally emit higher levels of greenhouse gases (GHG) than monogastric livestock systems as well as systems that produce plant-based protein[7,8,9] To use this evidence to advocate a global dietary shift away from ruminant p roducts[10,11,12] creates a curious paradox in light of the ever-growing human population and the need to produce more food with less resources. We present new evidence to demonstrate that per unit of nutrient density scores (NDS)[21,22], a measure of the overall nutrient value supplied by a food product, the demand for land suitable for human-edible crop production (arable land use: ALU) is considerably smaller under ruminant systems than monogastric systems This result is robust across multiple datasets encompassing both farm and regional scales. We demonstrate that carbon taxation against ruminant production systems has the potential to induce an extremely inefficient resource allocation at the national scale, resulting in socioeconomic losses far greater than its environmental benefits

Methods

Results

Conclusion