Energy assessment of peri-urban horticulture and its uncertainty: Case study for Bogota, Colombia

Scarce information is available about the energy use pattern of horticultural commodities in general and more specifically for peri-urban horticulture. Peri-urban horticulture in the outskirts of Bogota is an important source of vegetables for Colombia's capital city. Based on detailed follow-ups and periodic field measurements an output–input energy balance was performed with the main objective to study the energy use efficiency of those systems. An uncertainty analysis on the input factors and on the energy equivalents was then applied. Over a measurement period of 18-month, the energy use for coriander, lettuce, radish and spinach was investigated, respectively 12.1, 18.8, 6.6 and 10.7 GJ ha−1 were consumed in these cropping systems. Negative balances were observed for all species exception made for spinach where an output:input ratio of 1.16 was found. The two-way uncertainty analysis showed the highest uncertainty for N-based fertilization while no significant effect was observed for seeds in direct sowing crops. Sustainability of peri-urban horticulture around Bogota is compromised not only because of the city expansion but also due to its inefficient energy use. Technical improvements are required to ensure the environmental subsistence of this important sector for the metropolitan area of the city.