Aquaponic cultivation in the shadow of fish feed sources

Last changed: 03 June 2020
Cultivation of salad using hydroponics in a greenhouse. Photo.

The main objective of the project is to gather SLU researchers from different disciplines to write a research proposal focusing on developing a sustainable aquaponic system including feed based on black soldier fly protein and oil, with single cell proteins and marine waste streams.

Due to an increasing world population, climate changes and intensive resources needed for agricultural activities, that lead to decrease in natural resources (e.g. Water and land use), there is an increasing challenge for a secure provision of food globally. This puts demands on the development of efficient and sustainable production systems providing sources of high quality animal proteins and health promoting vegetables. Positive health effects of diets based on fish and vegetables are reported in numerous studies.

Development of sustainable and high yielding production systems for fish and vegetables therefore needs increased attention. Vegetable production in hydroponic cultivation system display sustainable cropping systems for food production. Water and nutrients are supplied according to the crop's demand and developmental stages of the crop. During recent decades, these systems have been refined with respect to decreased environmental impact, efficient nutrient supply and increased plant health.

Recirculating aquaculture systems (RAS) display a sustainable way to farm fish. RAS keep fish at high densities, in indoor tanks in a "controlled" environment, commonly recirculating more than 90 % of water.

Aquaponic systems combine RAS fish culture with closed hydroponic system and are considered as resource-efficient with low environmental impact since the closed water cycle decreases nutrient release, and thereby prevents eutrophication. A successful integration of fish and vegetable farming systems requests high quality and yield of both fish and vegetables that in turn is affected by the external conditions, the feed source as well as animal health.

Fish feed source, amount and quality are key factors in aquaponic systems since feed is both important for good fish growth. As an effect of feed source, the determined amount and composition of excreted feces displays also the main source for plant nutrition and quality. This makes the fish feed one of the major challenges in aquaponic system since it affects the nutrient balance in the system and thereby yield and quality of the products. Besides, sustainable aquaculture can´t rely on fishmeal and soy as a feed, and alternative protein and lipid sources are highly recommended and sought-after.

Different alternatives are of interest, in particular feed originating from insects and microbes grown on waste streams. In order to achieve a sustainable cultivation in aquaponic system with high quality products, information about the effect of alternative fish sources on the growth and quality of fish and vegetables as well as on the nutrient balance in the system is required.

The applied seed money are to be used to write and produce a research application focusing on developing a sustainable aquaponics system including feed based on black soldier fly protein and oil, with single cell proteins and marine waste streams.

Partners involved
  • Sammar Khalil from the Department of Biosystem and Technology, Faculty of Landscape Architecture, SLU.
  • Co- applicants; Markus Langeland from the Department of Animal Nutrition and Management, Faculty of Veterinary Medicine and Animal Science, SLU, Sabine Sampels from the Department of Molecular Sciences, Faculty of Natural Resources and Agricultural Sciences, SLU.

Facts:

The project started in 2018 and last for one year. The project is funded by SLU Aquaculture, which support cross-faculty collaborations to further strengthen aquaculture research at SLU. Read more about SLU Aquaculture, current research projects and upcoming calls.