Carbon dioxide sequestration capability of hazelnut orchards: daily and seasonal trends

Under the current global warming scenario, with temperatures expected to reach 1.5 °C above pre-industrial levels between 2030 and 2052, the role of terrestrial ecosystems’ vegetation in removing carbon (C) from the atmosphere takes on even more importance. In particular, there is a need for researchers to emphasize and further quantify the environmental role of vegetation types such as agro-ecosystems. Woody crops like orchards typically dominate the landscape and the rural economy in producing areas of the Mediterranean region. In this context, the present study aimed to quantify the amount of carbon dioxide (CO2) sequestered by one of the most important tree crop species widely diffused across the Mediterranean region: Corylus avellana L. (hazelnut). Overall, the results highlighted that the hazelnut orchards under consideration, subjected to routine horticultural care, sequestered a total amount of CO2 of 58.8 ± 9.1 Mg ha−1 year−1 (mean value), with the highest amount of CO2 sequestered recorded in May (12.4 ± 2.0 Mg CO2 ha−1 month−1). Considering also that the area covered by hazelnut cultivation is continuously increasing, we can conclude that this cultivation is important not only for the orchards’ nut production but also for their role as carbon sinks