Relación entre el índice de Turc y el rendimiento de la alfalfa en la España peninsular

Abstract

The modernisation of Spanish agrarian insurance demands the use of crops yield prediction models. Many yield prediction models are difficult to apply because data are not available. In this work, we studied the performance of Turc productivity index and its components to model alfalfa yields from climatic data. Data of alfalfa provincial yields from 1979 to 1995 and climatic data from 482 peninsular meteorological stations of 1966-1996 were use. Regression equations between provincial alfalfa jdeld and the Turc index and its components were obtained. A model based on seasonal dryness factors and the product of these by temperature was able to explain a large variability (87%). One component of Turc index, the annual dryness factor, explained larger variance (73%) that the Turc index per se, which confirms the importance of water deficit in Mediterranean agriculture. In conclusion, an index of easy calculation, using available climatic data and applied on provincial scale was able to estimate the vegetal mass crops in the conditions of peninsular Spain.