Agricultural water footprint of ethanol and sugar from sugar cane under fertigation production system.

The study has objective to calculate the green, blue and grey agricultural water footprint (WF) of ethanol and sugar produced from sugar cane, under subsurface fertigation production system, in Piauí State, Brazil. Sugar and ethanol production data in response to different irrigation levels (288, 492 and 675 mm), nitrogen fertigation (90, 113 and 160 kg ha-1 N ) and potassium (60 and 133 kg ha-1 of K2O) plus a control treatment (2,080 mm of rainfall, 75 kg N ha-1 and 75 kg ha-1 of K2O) were obtained from a trial under subsurface drip irrigation system, RB 867515 sugar cane variety, 1st ratoon, conducted in COMVAP - Sugar and Alcohol Inc., União county, Piauí State, Brazil. Under subsurface drip fertigation, the agricultural WF for sugar production ranged from 1,493 L kg-1 (1,175 L kg-1 - green water, 163 L kg-1 - blue water and 155 L kg-1 - grey water) to 1,172 L kg-1 (823 L kg-1 - green water, 267 L kg-1 - blue water and 83 L kg-1 - gray water). For ethanol production, the agricultural WF ranged from 2,081 L L-1 (1,638 L L-1 - green water, 227 L L-1 - blue water and 216 L L-1 - grey water) to 1,483 L L-1 (1,040 L L-1 - green water, 338 L L-1 - blue water and 105 L L-1 - grey water). Under non-irrigated condition, the agricultural WF for sugar production was 1,915 L kg-1 (1,763 L kg-1 - green water and 152 L kg-1 - grey water) and 2,658 L L-1 (2,448 L L-1 - water green and 211 L L-1 - grey water) for ethanol production. The agricultural WF for the ethanol production was superior to sugar production. Agricultural water footprint under fertigation was lower than that obtained under non-irrigated condition, and should be a recommended practice for increasing water productivity to sugar and ethanol production from sugar cane crop in the region evaluated

DIMPIVO: Programa computacional para dimensionamento de sistemas de irrigação pivô central.

O presente trabalho apresenta um programa computacional em linguagem TURBOBASIC (DIMPIVO) capaz de dimensionar sistemas de irrigação pivô central a partir da pressão de projeto no final da linha lateral. O modelo realiza uma análise hidráulica do sistema, selecionando bocais a partir dos valores de pressão e vazão determinados ao longo da linha lateral, na presença e na ausência de canhão final. Os resultados demonstram que o programa efetua uma seleção criteriosa dos bocais dos emissores, com ou sem o uso de reguladores de pressão, de tal forma a permitir uma adequada aplicação de água em toda a área

Desempenho agronômico de linhagens de arroz irrigado em ensaio de VCU no RS - safra 2011/12.

O objetivo deste trabalho foi avaliar o desempenho das linhagens de arroz irrigado em ensaios de VCU do programa de melhoramento genético da Embrapa, almejando possível lançamento de novas cultivares