Aquaponics as a Promising Strategy to Mitigate Impacts of Climate Change on Rainbow Trout Culture

Abstract

The impact of climate change on both terrestrial and aquatic ecosystems tends to become more progressively pronounced and devastating over the years. The sector of aquaculture is severely affected by natural abiotic factors, on account of climate change, that lead to various undesirable phenomena, including aquatic species mortalities and decreased productivity owing to oxidative and thermal stress of the reared organisms. Novel innovative technologies, such as aquaponics that are based on the co-cultivation of freshwater fish with plants in a sustainable manner under the context of controlled abiotic factors, represent a promising tool for mitigating the effect of climate change on reared fish. The rainbow trout (Oncorhynchus mykiss) constitutes one of the major freshwater-reared fish species, contributing to the national economies of numerous countries, and more specifically, to regional development, supporting mountainous areas of low productivity. However, it is highly vulnerable to climate change effects, mainly due to the concrete raceways, in which it is reared, that are constructed on the flow-through of rivers and are, therefore, dependent on water’s physical properties. The current review study evaluates the suitability, progress, and challenges of developing innovative and sustainable aquaponic systems to rear rainbow trout in combination with the cultivation of plants. Although not commercially developed to a great extent yet, research has shown that the rainbow trout is a valuable experimental model for aquaponics that may be also commercially exploited in the future. In particular, abiotic factors required in rainbow trout farming along, with the high protein proportion required in the ratios due to the strict carnivorous feeding behavior, result in high nitrate production that can be utilized by plants as a source of nitrogen in an aquaponic system. Intensive farming of rainbow trout in aquaponic systems can be controlled using digital monitoring of the system parameters, mitigating the obstacles originating from extreme temperature fluctuations.

Strategies for promoting sustainable aquaculture in arid and semi-arid areas – A review

“…As a result of such systems, quality fish protein and fresh vegetable products can be produced with less water than if both systems were operated independently (McMurtry et al, 1997;Crespi and Lovatelli, 2011 b;Yue and Shen, 2022). Additionally, innovative fish/vegetable co-culture systems use fish waste as direct inputs to produce vegetables, constantly recycling the same water (for example, aquaponics) (Vasdravanidis et al, 2022). In addition, recirculating systems are not affected by soil type, use a fraction of the water required by pond culture, and conserve land (Martins et al, 2010).…”

An Overview of the Implication of Climate Change on Fish Farming in Egypt

“…Meanwhile, the supplement, suspension feeders, and other organic extractive species are capable of further filtering the phytoplankton, as well as the dispersed small particle organic materials from both fish food and feces in the water column. From an environmental point of view, these modern fish farming systems represent a novel technology that improves production efficiency, while mitigating environmental impacts (pollution load, including GHGs emissions), diversifying fish production, animal welfare in aquaculture systems, climate change studies, soil depletion, technologies that mitigate the emergence of animal diseases or parasites, and reducing the use of antibiotics, chemical fertilizers, new feed ingredients, and carbon footprint [175,176].…”

The Influence of Water Nitrate Concentration Combined with Elevated Temperature on Rainbow Trout Oncorhynchus mykiss in an Experimental Aquaponic Setup

“…Aquaponics is considered to be one of the most efficient and sustainable animal protein production systems since fishes have better feed conversion ratios than other agricultural animals, and, in parallel, residual feed and fish waste can be converted into plant biomass [3]. Aquaponic systems combine recirculation aquaculture systems (RASs) technology for rearing fish together with hydroponics for plant cultivation, where plants grow in waterbased nutrients instead of soil [4,5]. Nitrogen is the main essential nutrient that the aquaculture system provides to the hydroponically co-cultured plants.…”

“…The rainbow trout Oncorhynchus mykiss is the most important cultured freshwater fish species in Europe [5]. In 2020, rainbow trout production represented 1.72% of global finfish aquaculture [8].…”