THE EFFECT OF CLIMATIC CONDITIONS ON HAZELNUT (CORYLUS AVELLANA) YIELD IN GIRESUN (TURKEY)

In this study the relationship between hazelnut yield and climatic conditions were analyzed. Black Sea Region, Turkey, is one of the most favorable habitat for hazelnut cultivation in the world. Having the highest economic value among various hazelnut cultivars cultivated in this region, Tombul hazelnut finds the optimum conditions-principal of these conditions is the climate one-in Giresun. Therefore, with the assumption that it can be accepted as the most suitable sample for this study, Giresun was selected. The time period between 1993 - 2007 which included reliable data on climate and production was analyzed. Among many factors effective on yield, climatic conditions have a principal role. With this purpose, the special climatic requirements of hazelnut during its each phenological period were examined and their effects on yield were analyzed. This analysis was made in two ways. The first one is the special climatic requirements analysis and the second one is the correlation and simple linear regression analysis. In the former the effect of daily, monthly and annual meteorological data in accordance with hazelnut's special climatic requirements on yield was analyzed year by year. In the latter, the correlation between climatic variables and yield was analyzed and then simple linear regression was performed. According to both analyses, the most considerable climatic variable affecting the yield was determined as temperature.