How Will the Changing Climate Affect Olive Trees?
It is said that even the olive tree, which has been considered a durable tree for thousands of years, will be seriously affected by the effects of climate change, and as a result, the crop, which has been considered a thousand-year-old source of livelihood, culture and trade, may be in danger.
Most Mediterranean olive groves were grown under rain-fed conditions and low-intensity management systems in the recent past. Shallow soils and steep terrain that could not be used for the cultivation of other crops were also utilized. Since it can be grown even in these conditions, olive cultivation has played an important role in local economies for years.
Now, increases in global food demand, shortages of human labor, and other socio-economic constraints such as the need to increase profitability are encouraging a shift to intensive and even super-intensive cropping systems. Crop profitability therefore becomes the main driver for change in crop management through cost reduction. These changes also bring about the need to irrigate and fertilize large areas to increase yield per area.
Olive trees and climate connection
Olive tree cultivation is limited to approximately 30 to 45 degree parallels throughout the world. In fact, centuries ago, geographical boundaries were determined by stating that the olive tree could be grown up to 53 km away from the Mediterranean coast. The olive tree does not grow in very cold or very hot climates. In other words, it is stated that the most suitable climatic conditions for growing the olive tree are represented by a climate that is today called a typical Mediterranean climate, representing the transition between the arid climate of North Africa and the temperate rainy climate.
Olive groves evolved with the Mediterranean climate and are known for their resilience to water scarcity, but in recent years it has become clear that even the olive tree, a symbolically resilient tree, is severely affected by the effects of climate change.
History and present of the olive tree
The geographical origin of the olive tree lies in the Eastern Mediterranean, corresponding to today’s Lebanon, Jordan, Syria and some neighboring regions, between 4000 and 3000 BC. Since the beginning of its history, the tree has brought much more than olives and oil. It is a substance that also has medicinal values and cosmetic benefits.
The history of the olive tree is parallel to the history of the Mediterranean and the history of gastronomy. So much so that this parallel is frequently expressed as “The Mediterranean ends where the olive tree stops growing.” The olive tree, together with the vine and wheat, forms the Mediterranean trilogy.
A tree affected by and influencing the climate
Each olive tree absorbs an average of 30 kg of CO2 per year, making olive groves an important factor in preventing climate change. Olive trees can reduce the effects of climate change to some extent through CO2 absorption, but they can also become victims of climate change. Increasing greenhouse gas emissions lead to an increase in the frequency of extreme weather events and an increase in temperatures. Lack of rainfall and resulting drought can cause water stress in the olive tree, and at the same time, higher temperatures can cause heat stress. This stress can physiologically damage trees, jeopardizing flowering and therefore olive production.
Before you start worrying about how you’ll make your salads and cook your meals in the future, remember that the climate-related repercussions will initially be mainly for producers and farmers.
Given the complexity and size of the food chain, there is a time lag between what happens in the field and what we find in the supermarket. This does not mean that you can sit back and relax, because the vulnerability of the olive tree to climate change means that these crops that we have relied on for thousands of years and that have survived many changes over the centuries will not be easily and cheaply available in the future.
