Vegetable Production in an Integrated Aquaponic System with Rainbow Trout and Spinach

Background: In an integrated aquaponic system, the ratio between nitrogen production and plant assimilation is a key factor for system efficiency. That is why plant density is very important to be appropriate. Aims: The aim of this study is to expose the performances of growth parameters, both in terms of quantity and quality, for Nores variety spinach (Spinacia oleracea) produced in an aquaponic integrated system along with rainbow trout (Oncorhynchus mykiss), under three plant densities (V1 - 59 plants/m2, V2 - 48plants/m2 and V3 - 39plants/m2). Materials and methods: The experimental design consist in a recirculating aquaculture system with 12 growing units, mechanical and biological water treatment units and four aquaponic units. Three plants densities were used (59, 48 and 39plants/m2). A fish stocking density of 136fish/m3 was used. Plants initial and final biomass was taken and a series of periodic measurements were made. Chlorophyll a, b and carotenoids, ash and dry matter were determined from spinach leaf. Results: The plant biomass gain registered good values and the quality of final plant products, given by the chlorophyll a, b, carotenoids and dry matter content were in the optimal variation interval, comparing to market spinach. Significant differences (p