Emergy analysis of organic horticultural systems

Enrique Ortega Rodrigues, José Guilherme Marinho Guerra, Renato Linhares Assis, Raul Lucena Duarte Ribeiro

Abstract


The industrial agriculture depends on a constant flow of non-renewable natural resources, which will not be able to meet the growing demand. The emergy analysis quantifies the sustainability of production systems, and its indicators are useful for the planning of agroecosystems and public policy. This research’s objective is to reveal the emergy diagnosis of five horticultural systems under organic management. A studied production unit (number 1) is a system of production and marketing of a small family-business type, in short chain. The other productive units (numbers 2, 3, 4 and 5) are family production systems, where the products are marked by intermediaries, in long chains. The performance evaluation of the emergy production systems followed the three recommended methodological stages: (i) elaboration of a systemic diagram; (ii) constructing emergy tables to calculate total emergy, and (iii) discussion of emergy indicators. Emergy flow analysis indicated the following: total emergy (Y) ranging from 1,72 to 6,24 E+17 seJ ha-1 year-1; Transformity (Tr): 6.72 E+06 to 3.14 E+07 seJ/J; high renewability (%R = 60 to 85%); Emergy Exchange Ratio (EER) ranging from 1,93 to 12,09; high benefit/cost (ESI - Emergy Sustainability Index) ranging from 3,54 to 39,71. These indicators show that the studied production systems can contribute to economic growth without causing serious disturbance to the environmental balance. The greater energy transformation efficiency in the organic production chain can be achieved by increasing commercialized production; but, to improve long term sustainability, the development strategies for commercialized production must restrict investments in non-renewable energy resources.


Keywords


Sustainability; emergy analysis; organic horticulture



DOI: https://doi.org/10.5777/paet.v3i3.868