Growth of marine macroalgae Ectocarpus sp. on various textile substrates

Composite materials for innovative urban farming of alternative food sources (macroalgae and crickets)

Facing an inexorable growth of the human population along with substantial environmental changes, the assurance of food security is a major challenge of the present century. To ensure responsible food consumption and production (SDG 12), new approaches in the food system are required. Thus, environmentally controlled, sustainable production of alternative food sources are of key interest for both urban agriculture and food research. To face the current challenge of integrating food production systems within existing structures, multidisciplinary discourses are required. Here, we bring together novel technologies and indoor farming techniques with the aim of supporting the development of sustainable food production systems. For this purpose, we investigated the feasibility of 10 composite materials for their innovative use as structural support in macroalgal cultivation (settlement substrates) and cricket rearing (housing). Considering material resistance, rigidity, and direct material-organism interactions, the bio-based composite polylactic acid (PLA) was identified as a suitable material for joint farming. For macroalgae cultivation, PLA sustained the corrosive cultivation conditions and provided a suitable substrate without affecting the macroalgal physiology or nutritional composition (carotenoids and chlorophylls). For cricket rearing, PLA provided a suitable and recyclable shelter, which was quickly accepted by the animals without any observed harm. In contrast, other common composite components like phenolic resin or aramid were found to be unsuitable due to being harmful for the cultivated organisms or instable toward the applied sterilization procedure. This multidisciplinary study not only provides profound insights in the developing field of urban indoor food production from a new perspective, but also bridges material science and farming approaches to develop new sustainable and resilient food production systems.

Developing the Use of Wool Rope within Aquaculture—A Systematic Review

To date, wool is an underutilised sustainable resource that has the potential to reduce the use of plastic within the environment. Wool can be manufactured as rope, but is this a viable innovation? To gain a comprehensive understanding of the economic viability of utilising wool rope in seaweed aquaculture, a systematic literature review was undertaken. The review focuses on wool, rope, natural and man-made fibres and seaweed farming, and used bibliometric and content analysis of peer-reviewed papers, with no timeframe requirements. It is important to explore alternative materials to reduce marine rope pollution; ghost gear, microplastics from abrasion and plasticrusts are now believed to be significant ecological problems. To date, the production of wool rope is limited, and its strength and durability within the fishing industry remain untested. It is important to understand whether wool rope is a useful alternative: does it have the same tensile strength, and can it be used within the industry without the risk of damage to the environment? There is currently a lack of research on natural rope fibres, resulting in limited access to commercial rope alternatives being used within the industry. This systematic review shows that there has been a large gap in wool research, with limited publications in recent years; however, the drive to increase sustainability (particularly within the marine environment) has increased. This is the first paper that combines both topics within one research study. Further research is needed to identify whether wool rope will provide a feasible alternative to polypropylene in terms of strength and durability, and how wool rope will perform, the length of time it can provide optimum service and within which seaweed farming practice it can offer a practical alternative to polypropylene.