One of the many sustainable development goals that are at the core is land use. In a study published in Nature Communications, the combination of international researchers from several institutions including PBL Netherlands, IIASA, and the Potsdam Institute for Climate Impact Research has attempted to disentangle the key dominants of global land use projections.
There are essential implications for the attainment of economic with the way we use available land. To this end, land use studies have been carried out in countries across the globe with many large-scale studies looking at future scenarios for our planet.
Researchers used various models for these exercises that result in diverse and sometimes inconsistent projections. More recently, specifically in the context of climate change research, researchers have been working to produce more harmonized results by using a commonly approved set of scenarios, the so-called Shared Socioeconomic Pathways (SSPs). These attempts were the first step towards harmonization and consistency, but not all differences between model results could be reconciled.
This new study has made researchers decompose the role of each important scenario driver (including future population, income, dietary patterns, and level of land protection) in the different models to identify what the causes of the discrepancies were. The research utilized systematic sensitivity experiments to explain the spread in models and scenarios and to identify the main factors determining the transition to a more sustainable (or unsustainable) land future.
The study results indicate that among the many land use change drivers, our future land footprint will mainly depend on the interplay between population growth, agricultural efficiency, land use regulation, and consumption changes. Moving beyond the qualitative relations, the researchers also identified the relative contribution of these factors and illustrated how the combination of land use regulation, agricultural efficiency, and dietary changes could help limit human pressure on land while safeguarding food security.
In the study, the team was able to assess what levers could be used to mitigate the future impact of specifically population growth, which was identified as a significant driving force, increasing agricultural productivity by decreasing the amount of land needed to feed each.
Also, the results reveal that enforcing more efficient land use protection for forests and other biodiverse natural habitats mitigates the most adverse impacts of the expansion of agricultural land. Lastly, shifting diets towards less resource intensive products, especially those with a lower share of livestock products, can also alleviate the social pressure on ecosystems and the demand for land.
Ultimately, the team believed that the study is an important milestone for the research community as it will help to elaborate more consistent quantitative scenarios across studies, and ease the comparability of results for policy guidance on all significant sustainability challenges related to land use, including climate change impact and mitigation, biodiversity, and food security.