Climate Changes Challenge Olive Production

Most Mediterranean olive orchards were formerly produced under rainfed circumstances and low-density management methods, primarily in marginal locations typified by shallow soils and steep topography that could not readily be exploited for other crop production. Under these conditions, while playing an important role in local economy, olive production may indeed help to the preservation of ecosystem natural resources through soil conservation, improved soil water retention, and carbon sequestration.

 

Today, olive trees confront new difficulties and risks, the most serious of which are connected to climate change. Increased warmth and drought, as well as a rise in the frequency of extreme weather events such as heatwaves, are some of the issues that farmers will face in the future decades.

 

Recent reports show that significant warming has occurred in the Mediterranean region over the last 40 years, with annual temperatures now about 1.5 °C higher than in the preindustrial period (1880–1899) and well above current global warming trends (+1.1 °C), and we have experienced the six warmest years on record globally since 2014. Increasing temperatures were accompanied by a succession of severe heat events that occurred at an unprecedented rate in terms of length, severity, and frequency, and the frequency of cold extremes has decreased significantly.

 

In addition, a more obvious declining trend in annual total precipitation is anticipated, particularly across the west-central Mediterranean region and the Mediterranean region's southern coasts, but at varying local rates. Future climate forecasts for the Mediterranean area are notoriously dire. Precipitation predictions in this region indicate a general decline, which will reduce soil water availability. Because of the difficult summer weather conditions, including limited precipitation, intense heat, and strong solar radiation, the Mediterranean area is already characterized by plant heat and water stressors.

 

Furthermore, night time temperatures will likely to rise, resulting in even more thermal stress. Another expression of climate change is an increase in the frequency of extreme weather events, such as heatwaves, hail, floods, and wildfires. Under climate change scenarios, the frequency and amplitude of these occurrences are expected to increase, leading to an increase in the severity of drought and heatwave periods throughout the Mediterranean Basin.

 

Future climate changes will have a significant impact on the agricultural industry as a whole, and the olive tree sector in particular. Regarding perennial crops, such as olive trees, these projections are expected to have severe negative effects under future climatic conditions, particularly on water relations, oxidative pathways and other physiological processes, phenological timings, final yield, and quality attributes.

 

Recent research on olive trees have revealed that this crop can be severely impacted by climate change, particularly in Mediterranean-type regions. Rising temperatures, for example, may have a significant influence on this crop. Temperature rises are predicted, which may lengthen the growth season. This will also result in alterations in phenological dates, notably blooming, with potentially negative consequences.

 

Furthermore, rising temperatures and increased evapotranspiration hasten fruit ripening, necessitating early harvests, albeit at lower maturity levels. Temperature rises may also result in a reduction in chilling conditions. Insufficient chilling leads in poor fruit setting, which has a negative impact on ultimate yields since some olive types develop malformed floral buds and fruits under these conditions.

 

Drought is regarded as a major limiting factor for agricultural output. Although olive trees are a drought-tolerant plant, water stress can cause a variety of negative effects, including reduced flowering and fruiting, reduced leaf area, restricted photosynthesis, flower abortion, and cluster abscission. Due to rising water stress conditions, these estimates may result in an overall decline in yields through 2080.

 

Nonetheless, all of these research agree that climate change would have a detrimental influence on olive tree yields in parts of the Mediterranean Basin's hottest and driest regions. The effects of pests and illnesses are another element of climate change. Indeed, research show that climate change is already impacting Mediterranean areas and making native olive tree varieties more susceptible to disease.

 

Crop responses to adverse conditions are strongly tied to the implemented adaptation measures. Proper management of the negative impacts of climate change may provide competitive advantages to early-adopting growers no matter is short term or long term adaptation. 

References

 

1. New trends in olive orchard design for continuous mechanical harvesting 2010

2. Olive groves: ``The life and identity of the Mediterranean'' 2003

3. An application of Life Cycle Assessment (LCA) as a green marketing tool for agricultural products: the case of extra-virgin olive oil in Val di Cornia, Italy 2014

4. A sustainable model for the management of olive orchards located in semi-arid marginal areas: Some remarks and indications for policy makers 2013

5. Modelling potential growth and yield of olive (Olea europaea L.) canopies 2006

6. Climate change projections for chilling and heat forcing conditions in European vineyards and olive orchards: A multi-model assessment 2019

7. Olive phenology as a sensitive indicator of future climatic warming in the Mediterranean 2000

8. Fine-scale ecological and economic assessment of climate change on olive in the Mediterranean Basin reveals winners and losers 2014

9. NCEI Ocean Heat Content, Temperature Anomalies, Salinity Anomalies, Thermosteric Sea Level Anomalies, Halosteric Sea Level Anomalies, and Total Steric Sea Level Anomalies from 1955 to Present Calculated from In Situ Oceanographic Subsurface Profile Data (NCEI Accession 0164586). 2021

10. Australian climate extremes at 1.5 °C and 2 °C of global warming. 2017

11. Heat wave changes in the eastern Mediterranean since 1960. 2010

12. Global observed long-term changes in temperature and precipitation extremes: A review of progress and limitations in IPCC assessments and beyond. 2016

13. Observed coherent changes in climatic extremes during the second half of the twentieth century. 2002

14. Observed Changes in Daily Precipitation Extremes at Annual Timescale Over the Eastern Mediterranean During 1961–2012. 2018

15. Trend analysis of annual and seasonal rainfall time series in the Mediterranean area 2010

16. Observed precipitation trend changes in the western Mediterranean region. 2017

17. Crop responses to climatic variation. 2005

18. Implications of future bioclimatic shifts on Portuguese forests. 2017

19. Viticulture in Portugal: A review of recent trends and climate change projections. 2017

20. What Is the Impact of Heatwaves on European Viticulture? A Modelling Assessment. 2020

21. Plant drought stress: Effects, mechanisms and management. 2009

22. Physiological behaviour, oxidative damage and antioxidative protection of olive trees grown under different irrigation regimes. 2007

23. Olive tree irrigation as a climate change adaptation measure in Alentejo, Portugal. 2020

24. Effect of water deficit on leaf phenolic composition,gas exchange, oxidative damage and antioxidant activity of four Greek olive (Olea europaea L.) cultivars. 2012

25. The role of nighttime water balance on Olea europaea plants subjected to contrasting water regimes. 2018

26. Effects of CO2 Atmospheric Fertilization on Greenhouse Production of Olive Trees
(Olea europaea L. ‘Arbequina’). 2008

27. Heat requirement for the onset of the Olea europaea L. pollen season in several sites in Andalusia and the effect of the expected future climate change. 2005

28. The effects of drought on the water use, fruit development and oil yield from young olive trees. 2009

29. Influence of different irrigation regimes on crop yield and water use efficiency of olive. 2010

30. Climate change projections for olive yields in the Mediterranean Basin. 2020

31. A comparison of the climate risks of cereal, citrus, grapevine and olive production in Spain. 2009

32. Phenolic compounds in olive oil: Antioxidant, health and organoleptic activities according to their chemical structure. 2009

33. Olive flowering as an indicator of local cli1matic changes. 2005

34. Olive flowering trends in a large Mediterranean area (Italy and Spain). 2010

35. Influence of temperature on the growth and development of olive (Olea europaea L.) trees. 2008

36. Assessment of the impact of climate change on the olive flowering in Calabria (southern Italy). 2012

37. Phenological models to predict the main flowering phases of olive (Olea europaea L.) along a latitudinal and longitudinal gradient across the Mediterranean region. 2015

38. Optimizing olive harvest time under hot climatic conditions of Jordan Valley, Israel. 2014

39. Impact of changes in mean and extreme temperatures caused by climate change on olive flowering in southern Spain. 2017

40. Drought Stress Effects and Olive Tree Acclimation under a Changing Climate. 2019

41. Soil water content and olive tree yield responses to soil management, irrigation, and precipitation in a hilly Mediterranean area. 2018

42. Mediterranean Olive Orchards under Climate Change: A Review of Future Impacts and Adaptation Strategies 2020