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- Aquaponics as a sustainable and healthy food production system for PortugalPublication . Mata, F.; Dos Santos, Maria José Palma LampreiaThe aquaponics biological cycle Aquaponics has enormous potential in the regulation and recycling of valuable nutrients, otherwise lost to the environment with pollution potential. Aquaponics integrates freshwater aquaculture and hydroponics in a mini ecosystem. It uses the water of a Recirculating Aquaculture System (RAS) in soilless plant farming. The process includes a biofilter where nitrifying bacteria oxidize ammonia, resulting from fish excreta or uneaten feed, into nitrates and nitrites. While fish are extremely sensitive to ammonia, they are more tolerant to nitrates and nitrites. Nevertheless, these need also to be removed from the fish environment before accumulation to toxic levels. This is where hydroponics may come in as a useful manner of disposing nitrogen off the RAS. Nitrogen is the main macronutrient for plant growth, therefore an indispensable element in fertilization. The advantages of combining a RAS with hydroponics becomes therefore evident as a win-win solution for the problematic nitrates of the RAS and the expensive nitrogen fertilizers of plant production.
- Consumption of honey in Portugal: consumers’ attitudes, perceptions and trendsPublication . Mata, F.; Dos Santos, Maria José Palma LampreiaConsumers’ attitudes about reveal important information about the production and supply chain of food and the commercialisation process (Unnevehr et al., 2010). To fully understand a consumption market, it is important to study the symbolic representations of consumption habits (Bekker et al., 2017). The consumer perceives consumption accordingly to social norms and values, and consumption habits cannot be analyzed as individual phenomena. Choices are under the influence of norms, values, taboos, permissions, prohibitions, and beliefs (Andorfer & Liebe, 2013). The consumers’ attitudes have been considered important determinants of their behaviour. The Ajzen’s Planned Behaviour Theory (APBT) (Ajzen, 1991) is based in the presumption that people behave in a sensible way, consider the information available, and consider the implications of their actions. The theory postulates that a person’s interest to perform or not a certain behaviour is a direct function of individually and socially related variables. The individual component is based in the individual attitude or mood to react favourably or unfavourably to an object, individual, institution, or event (Kim and Hunter, 1993). The social component includes the subjective norms determined by the perception of the social pressures acting on the individual, to perform or not a certain behaviour (Ajzen 1991