Precipitações pluviais da pré-estação chuvosa no período chuvoso e suas influências na produtividade agrícola da Paraíba.

Abstract

This study was carried out to determinate if there is relationships between early rainy season precipitations (three months) with rainy season (seven months) precipitations during 1975-2005, in six micro regions homogeneous pluviometricly of Paraíba State, Littoral (Litoral), Meadows (Brejo), Agreste, Cariri/Curimataú, Sertão and Alto Sertão. Were analyzed the relationships between production season rainfall for cultures of Sugar-cane and Pineapple in the micro regions of Litoral and Meadows. And the relationships between the seven moths of production season rainfall and Cotton productivity in the micro region of Sertão and of Sisal in the micro region of Cariri/Curimataú, all of them to 1990-2005. The three micro regions of Littoral, Meadows and Agreste has been early rainy season (February, March and April) representing around 40% of rainy season precipitations (February to August). While as the micro regions of Cariri/Curimataú, Sertão and Alto Sertão registered the early rainy season (November, December and January) representing around 20% of rainy season precipitations (November to May). With rainy season precipitations estimative can will to decide to plant, or not, in a determinate micro region. Tests accomplished with polinomial regression equations using only early rainfall season or rainy season like independent variable, did not sufficient to estimate Sugar-cane productivity on the Littoral, therefore small rainfall quantities don’t supply the crop water contents. Pineapple productivity didn’t present significant correlations to micro regions Littoral and Brejo rainfalls. Strongs correlations were obtained between the rainy season precipitations and the Cotton productivity in the Sertão, and to Sisal in the ariri/Curimataú of Paraíba State.