Tree-Crop Landscapes: Learning from the Past for the Food of the Future
Spring invites walking around, enjoying the sun, the humming bees, the singing birds and the awakening landscape. I am dreaming of a mosaic landscape that thrives and provides us with an abundance of food. But where does the food we eat come from? Our food (and the food we feed our animals) mostly consists of annual plants, such as grain and vegetables. They are grown on arable land that is ploughed and/or treated with pesticides. Ploughing fields not only leads to compaction and destruction of life in the soil, but also to soil erosion. At a global scale, we loose in average 10 to 40 times more soil through erosion than natural regeneration provides.*
Having that in mind, I was searching for alternatives: What did people eat before that short period in human history we are living in today, in which nutrition is so intensely based on annual agriculture? How did they produce their food, and what did landscapes of food production look like? The answer: For millennia, our human ancestors were hunting and gathering sustainably in food forests, tree-crop landscapes and savannas. They selected and protected useful plants and thus contributed to their dissemination.
Do we still have such sustainable systems nowadays? How did these landscapes evolve in the last centuries? What can we learn from the accompanying practices for future food production? These questions led us to study the history of tree-crop landscapes in the Mediterranean.
Mediterranean tree-crop landscapes: a wealth of histories
Until today, the Mediterranean basin is known for its beautiful tree-crop landscapes with a vast biodiversity, such as the oak landscapes in the Spanish dehesas, the famous chestnut landscapes on Corsica, France, and the widespread olive landscapes of Morocco.
Nowadays, traditional landscapes are endangered by either intensification of land use or abandonment of management. Human influence is not only at the origin of these tensions, but also contributed to the very formation of the landscapes: Tree-crop landscapes in the Mediterranean are closely intertwined with human culture and co-evolved with human land management.
In our 2020 study, we examined the history of nine tree crop landscapes in the Mediterranean from 1800 until today, namely three cork-oak (Alentejo, Portugal; Kromerie-Mogod mountains, Tunisia; Extremadura, Spain), three chestnut (Corsica, France; Apennines, Italy; Aegean, Turkey) and three olive landscapes (Lesvos, Greece; Baena, Spain; Rif, Morocco).
Across these diverse landscape histories, we found some common patterns: In the last 200 years, landscape-change dynamics were increasingly accelerating, and a trend from multiple values and functions towards a mono-causal use was apparent. Besides these commonalities, each landscape revealed its own exciting history of change, each with its individual evolution, tightly interwoven with human culture. We categorized the processes of change the landscapes underwent into expansion, continuity, polarisation, intensification, abandonment and renaissance. Their distribution across all landscapes and examination periods is visualized in this graph:
These landscape changes were driven by diverse, often interrelated forces, such as sociocultural, political, technical, economic and natural factors. The history of Corsican chestnut landscapes provides one exciting example of how these forces have been interweaving during the last 200 years.
Corsica: chestnuts as a symbol of independency
In early 19th-century Corsica, chestnut trees represented not only a resource used for multiple purposes and a key component of local livelihoods, but also an important component of local cultural identity, expressed for example through traditional craft products developed by local people.
French rule, on the other hand, aimed to defame chestnut as a staple food: In order to subvert the independency of the Corsican population from the mainland, the French governors designated chestnuts as “the food of laziness” and restricted their growing. However, becoming aware of the power they held, Corsicans continued cultivating this crop: Chestnut production rose to a symbol of Corsican resistance and freedom.
Since the 1850s, however, Corsican chestnut culture collapsed, and the trees’ cultivation was more and more abandoned. This happened for multiple reasons: One driver was the changing lifestyle of the people on the French mainland and the Corsicans’ wish to adapt. Together with a wave of outmigration, the two world wars increased worker shortage in harvest seasons. In addition, upcoming diseases — mainly chestnut blight and ink disease — threatened chestnut production, together with economic problems linked to transnational free market dynamics and competition for cheap prices.
In the 1980s, Corsican chestnut landscapes experienced a renaissance, which was driven by people’s deliberate efforts: Local initiatives were established to revive chestnut culture and the related economy; production and processing methods were improved due to technological progress. Up until today, there are and have been tensions between the aim of multifunctional and diverse traditional systems and profitable economic production, as the first is often more labour-intensive and thus not profitable nowadays.
Tree-crop landscapes for future?
In times of global challenges such as biodiversity loss, climate change and soil degradation there is an urgent need for sustainable landscape management. Tree-crop landscapes are known for their high potential as a sustainable alternative to current non-sustainable annual agriculture. Much can be learnt from the history of tree-crop landscapes, from their evolution and from the driving forces behind.
Against this background, we derived some key lessons for sustainable landscape management from our multi-site study:
- For a successful transformation towards sustainable land management, the inherent complexity of landscapes has to be considered.
- Driving forces are interrelated and changes are mostly multicausal across natural, political, technological, sociocultural and economic factors. However, in certain cases, there are dominating drivers that need special attention, such as political restrictions or civil strife. A multi-sectoral, holistic approach is needed to understand and cope with this complexity.
- Profitability is the key driver for the existence and stewardship of tree-crop landscapes.
- Although often not recognized, cultural and social drivers also play an important role for the management of tree-crop landscapes.
- Historical analysis of driving forces of landscape change can guide decisions for future landscape management.
Multifunctional and diverse tree-crop systems have a high potential to cope with today’s and future challenges, compared to forestry or annual cropping systems.
Let´s plant the diverse tree-crop landscape of the future!
Full Study: Wolpert, F., Quintas-Soriano, C. & Plieninger, T. (2020). Exploring land-use histories of tree-crop landscapes: a cross-site comparison in the Mediterranean Basin. Sustainability Science 15. Online: https://doi.org/10.1007/s11625-020-00806-w
*Pimentel, D. & Burgess, M. (2013). Soil Erosion Threatens Food Production. Agriculture. doi:10.3390/agriculture3030443
