Variety Is Key

Newswise — University of Bonn study shows where diversified farming also makes
economic sense

Where and how can diversified farming practices be put to profitable use in
order to boost both productivity and biodiversity? Researchers at the
University of Bonn have tackled this question in a study that has now been
published in “Communications Earth & Environment.”

Agriculture, like other sectors of the economy, is a profit-driven business.
Simple cultivation systems such as monocultures have therefore become firmly
established, because they promise higher returns. However, they are more
susceptible to diseases and parasites, which can cause total crop failure
among other things. Diversified cultivation practices such as mixed cropping
and crop rotation offer a sustainable alternative. It has already been
scientifically proven that they can be profitable, perhaps even more so than
monocultures. But under what conditions will these diversified farming
practices turn a profit? And how can they help to intensify agricultural
systems in a sustainable way?

A research team from the Center for Development Research at the University
of Bonn applied a method taken from ecology and used for modeling species
distribution to their study so that they could make predictions about where
in the world diversified farming practices could be profitable. To this end,
lead author Hannah Kamau, a doctoral student and member of Junior Professor
Lisa Biber-Freudenberger’s working group in the Innovation and Technology
for Sustainable Futures Transdisciplinary Research Area at the University of
Bonn, considered over 2,000 locations all over the world that were found to
have profitable diversified farming practices as well as socio-economic
conditions that determine profitability: population density, access to local
markets, electricity supply, gross domestic product per capita and
governance.

Hannah Kamau then predicted which other regions of the world had similar
conditions as the observed locations of profitable diversified farming
practices . Her predictions suggest that the Global North and parts of the
Global South that are close to urban centers are particularly suitable for
profitable diversified farming practices. “Developed infrastructure played a
key role in forecasting suitable areas,” she explains.

In addition to identifying potentially suitable regions, Kamau also
determined how production in each individual area could be increased
sustainably. “There are two approaches to boosting production,” she says.
“The first is extensification, which means expanding agricultural areas.
The other is intensification, i.e. ramping up cultivation density. Depending
on the region, diversified farming practices can help make both
extensification and intensification more sustainable. But each approach has
its risks.”

Which approach is more promising depends on the region in question.
Agricultural land in Western Europe, China, parts of India and Brazil as
well as Eastern Europe that is already being intensively farmed could
benefit from various forms of extensification such as incorporating mixed
planting and lowering the cultivation density. While areas in sub-Saharan
Africa and parts of Brazil, India,Tajikistan as well as Canada, and
Australia could benefit from intensification according to the study. Other
areas may be suitable for both options, such as most parts of West Africa.

Funding: The study was funded by the German Federal Ministry of Education
and Research (BMBF) as part of the project entitled “At the Science Policy
Interface: LANd Use SYNergies and CONflicts within the framework of the 2030
Agenda” (LANUSYNCON) [01UU2002].

Publication: Hannah Kamau, Shahrear Roman, Lisa Biber-Freudenberger: “Nearly
half of the world is suitable for diversified farming for sustainable
intensification,” in “Communications Earth & Environment.” DOI:
https://doi.org/10.1038/s43247-023-01062-3