Grass Growth and N2O Emissions From Soil After Application of Jellyfish in Coastal Areas

Abstract

The supply of nutrients for agricultural production faces enormous challenges as food security and sustainability goals have to be ensured. Processing of marine biomass has high potential to provide nutrients for agricultural purposes in coastal areas. One underexplored resource are jellyfish, which occur as blooms and by-catch of the fishing industry. In this context, a pot experiment investigated the effects of jellyfish as a fertilizer on biomass accumulation of annual ryegrass (Lolium multiflorum), and its effect on the important greenhouse gas N2O as a sustainability indicator of novel fertilizers. Dried and ground jellyfish was applied [3 species: Aurelia aurita (AA), Cyanea capillata (CC), Periphylla periphylla (PP)] and compared with an unfertilized and a mineral fertilized (calcium-ammonium-nitrate, CAN) treatment. Dried jellyfish and CAN were applied at equal N rates of 5 g N per m2. The N2O-fluxes from soil were measured over 56 days after fertilizer application. Grass dry matter yields, when using CC and PP treatments, were not significantly different to the CAN treatment (p > 0.05). After reducing its salinity, AA also showed no differences to CAN on plant growth and the lowest coefficient of variation for dry matter yield as an indicator for yield stability. Accumulated N2O-emissions were lowest in the control and were 3-times higher in AA and CC compared to CAN (p < 0.05). If salinity levels are moderate, jellyfish application to soil can compete with artificial mineral fertilizers in terms of N-supply for above- and belowground yield response, regardless of jellyfish species used. However, elevated N2O-emissions are likely to affect its suitability for large-scale application. Nevertheless, if energy-efficient methods of drying and desalination of jellyfish can be developed, in coastal areas dried jellyfish is a valuable fertilizer in coastal areas, particularly in situations where nutrient supplies for agriculture are limited.

Food Security and Sustainability: Discussing the Four Pillars to Encompass Other Dimensions

“…The same happens with the different pressures over the agricultural land associated with, for example, the urbanization and ever-growing population [32]. In any case, the farming sector and the associated dimensions are determinants for sustainable food security [33], including animal welfare [34], and the new technologies open new opportunities [35], including for monitoring [36] and assessments [37]. The population growth is particularly worrying in countries such as India, for example [38], but other specific contexts also deserve special attention [39], including those from Africa [40].…”

Valorization of Marine Waste: Use of Industrial By-Products and Beach Wrack Towards the Production of High Added-Value Products

“…Hence, new value chains and business models should be developed to change the perspective of beach wrack from a cost-intensive to a profitable activity. Traditionally, this biomass was either composted (also with fresh-terrestrial green waste, thus contributing to the blue-green innovations) and utilized as a biofertilizer or for biomethane production (Barbot et al, 2016;Weinberger et al, 2020;Borchert et al, 2021). However, there are still unexploited opportunities to maximize its valorization potential in other industries, thus maintaining the circularity of financial and biological resources.…”

Jellyfishing in Europe: Current Status, Knowledge Gaps, and Future Directions towards a Sustainable Practice

“…Other countries emerging as significant producers include Thailand, India, Vietnam, Indonesia, and Mexico [10]. Recent advances have been achieved in assessing the value of jellyfish in traditional industries and in finding novel uses for jellyfish products [13][14][15], (www.gojelly.eu) (access on 25 August 2021), including as (1) marine natural products for biomarkers and biomedical applications [16], (2) agricultural fertilizer [15,17,18], (3) farmed fish and animal feed [9,19], (4) a collagen source [20][21][22], (5) microplastic filters in wastewater treatment plants [23], and (6) novel human food products [8,14,24,25], along with (7) the exploration of jellyfish palatability in western markets [14]. This is expected to lead to new markets for jellyfish as a raw material and thus to large-scale jellyfish fisheries or even aquaculture and jellyfish cultivation.…”