Social Justice Causes Short-Term Increase in Land Use
ResearchZEW Study on the Relationship between Income, Consumption and Biodiversity
The initial effect of less income inequality is a higher biodiversity footprint, in particular driven by the land use implications of a change in consumption. This is mainly due to increased meat consumption, as shown by a new study conducted by ZEW Mannheim in collaboration with the German Centre for Integrative Biodiversity Research (iDiv) and ESSEC Business School. The analysis is based on income and consumption data from over 200,000 US households. The results can also be applied to Germany and other European industrialised countries.
“The main driver of land use is the rising consumption of meat, which leads to an increase in the demand for pasture and arable land. Since meat consumption does not continue to increase at the same rate with rising income, the average land use per dollar decreases again beyond a certain income level,” co-author Professor Lutz Sager from ESSEC Business School cites as the reason.
“Redistributing income to poorer households can increase pressure on land use in the short term. We estimate that complete income equality in the United States would increase average land use by 3.2 per cent, which translates into around 189,000 square kilometres of additional land,” explains Tim Kalmey, researcher in ZEW’s Research Unit “Environmental and Climate Economics” and co-author of the study.
“This shows that environmental and distributional objectives do not automatically align. To achieve national and global biodiversity goals, additional conservation measures are needed, if income inequality is reduced at the same time,” Kalmey concludes.
Technology helps – Consumption habits hurt
From 1996 to the early 2010s, the biodiversity footprint became smaller, despite rising consumption, because of efficiency gains in production and supply chains. If, for example, technologies had remained at 1996 development levels, the average land use per household would have increased from 4.8 to 7.5 hectares, or by 65 per cent. Thanks to technological progress, the actual average fell to 4.6 hectares in 2022.
However, since 2014, technological progress has no longer been sufficient to compensate rising consumption. In particular, the increased consumption of meat and other animal products has had negative consequences for biodiversity.
Findings also relevant for Germany and the EU
“We assume that the study findings can be transferred to European consumers as well, as the general relationship between consumption patterns and income is similar across Western industrialised nations. Furthermore, the biodiversity impacts of consumption are comparable across countries due to the use of similar technologies and global value chains,” explains co-author Dr. Jasper Meya from iDiv. “In addition, existing studies using European household data suggest a similar structural relationship between biodiversity footprint and household income.”
Data foundation
The study is based on data from over 200,000 US households from the Consumer Expenditure Survey, which has collected detailed income and expenditure information between 1996 and 2022. These data were linked to global biodiversity intensity levels of various consumption goods, taking into account both domestic biodiversity effects and impacts in other countries. This enabled the calculation of consumption-driven biodiversity footprints for individual households over a period of more than 25 years. Land use associated with the production of goods is an important driver of biodiversity loss and responsible for a major part of the loss of global biodiversity.
