Impact of bioclimatic and climatic factors on Ficus carica L. yield: increasing the economy and maintaining the food security of Jerusalem in Palestine

Abstract

Ficus carica L. is a tree that plays a key role in the economics of Palestine, contributing to supporting the economy and maintaining its food security. Aims: The aim of this study is to determine the impact of climatic and bioclimatic factors on figs (Ficus carica L.) in order to contribute to the economy of the Jerusalem area in Palestine. Materials and methods: We analysed meteorology data for Jerusalem from the Palestine Meteorological Department, recorded in the period from 1993-2008, and data on (rain-fed) plant yields from the Palestinian Central Bureau of Statistics (PCBS) and the Palestinian Ministry of Agriculture for the same years. We used Salvador Rivas-Martinez’s bioclimatic classification of the Earth to analyse the data from the Palestinian meteorological station for the period 1993-2008, namely the simple continentality index, compensated thermicity index, annual ombrothermic index, water deficit and soil water reserves. Results: The application of a principal component analysis (PCA) revealed that the Jerusalem type plots located to the right of axis 2 during 1993-1997 were affected by precipitation, simple continentality index and annual ombrothermic index, with a large proportion of the variance explained by axes 1 (97.57%) and 2 (1.656%). Conclusion: as a conclusion, fig trees were adapted to a dry to humid ombrotype and an inframediterranean to mesomediterranean thermotype, characterised by dry summers with temperatures between 18-30o C; the optimum fig yield is obtained with simple thermicity index values of 18-22, an annual ombrothermic index of over 2.5, and a compensated thermicity index of 250-450.