Resumo

MENA-MARTIN, Helbert Antonio; TIJERINA-CHAVEZ, Leonardo; ACOSTA-HERNANDEZ, Rafael  e  MEJIA-SAENZ, Enrique. Technical and economical evaluation of the central pivots systems. Terra Latinoam [online]. 2010, vol.28, n.2, pp.177-184. ISSN 2395-8030.

This study was conducted in three communities of Yucatan, Mexico (Tizimin, Becanchen, and Tekat), to determine the impact of central pivot systems in the production of corn and grass in the region. The uniformity distribution (UD) and the coefficient of uniformity (CU) were below the recommended values: CU 46.9, 60.66, and 55.44%, and UD 62.38, 71.97, and 72.62% for Tizimin, Becanchen, and Tekat, respectively, indicating inadequate operation, as well as faulty agronomic management. On the other hand, the applied volume of water caused a favorable response since, for each cubic meter applied, the increase in grass dry matter yield was 4.4 kg ha^-1 year^-1. The economic analysis indicated water productivity of 3.3, 1.11, and 17.38 $m^-3 year^-1 and land productivity of $4416.6, 7868.6, and 3470.7 ha^-1 year^-1 for Tizimin, Becanchen and Tekat, respectively. The comparison of yields and operating costs of the cultivation of rainfed corn, furrow-irrigated corn and central pivot irrigated corn indicated that the yield obtained with central pivot was 2 Mg higher than the rainfed corn crop yield, which does not justify investment in these systems. Likewise, for the case of equipment for irrigating grass, the obtained yield does not justify the investment. To make irrigated cultivation profitable, it is necessary to incorporate an activity that provides added value such as production of feed for fattening beef cattle. This was indicated by increments in utilities: from $4416.6 and 3470.7 ha^-1 year^-1 obtained in Tizimin and Tekat, respectively, with grass production, to $20 350.2 and 15 754.4 ha^-1 year^-1, respectively, with livestock feed.

Palavras-chave : evaluation; productivity; sprinkler.