Sunday, April 15, 2012

Sustainable Aquaculture - Scottish Marine Institute

"Turning waste into a useful product is the basic premise of integrated multi-trophic aquaculture (IMTA). By using waste products from fin-fish aquaculture as food and nutrients for other organisms then we can reap the dual benefits of reduced pollution and increased productivity. The principle is simple, the practice however is complex,: ongoing research at the Scottish Marine Institute aims to overcome some of these complexities and bridge the gap between theoretical concept and industrial application."

Nualgi simplifies the use of animal waste to grow diatoms and since diatoms are good food for fin fish, they benefit from the natural feed.

Tuesday, April 10, 2012

The Silicon Cycle

The marine Silicon cycle

There is a close coupling of silicon and carbon in global biogeochemical cycling. About three quarters of the primary production in coastal and nutrient replete areas of the world oceans is carried out by diatoms, a phytoplankton group that essentially needs silicon (Si) for the build up of their opaline shells. In low nutrient areas diatoms still contribute to about one third of the marine primary production. Silicic acid, Si(OH)4 and its ions, is the biologically available form of Si in the marine environment and its surface water concentration can severely limit diatom biomass build up. Hence, efforts to understand the marine carbon cycle should also take into account the silicon nutrient cycle. Three stable isotopes of Si, 28Si, 29Si, and 30Si, exist with 28Si being the most abundant (92.2 % to 4.7 % to 3.1 %). Diatoms taking up silicic acid prefer the lighter isotope 28Si and, thus, progressively enrich the surface ocean silic acid in 29Si and 30Si relativ to 28Si.

Sunday, April 1, 2012

Biodiesel from Diatoms

Diatoms grown in a tank using Urine as a the source of nutrients N and P and Nualgi as the micro nutrient input.

Nualgi Poster

Nualgi causes Diatom Algae to grow.

Diatoms consume Nutrients N and P, and CO2, and give Oxygen.

Aerobic bacteria consume Oxygen and give CO2.

Diatoms are consumed by Zooplankton and these by Fish, thus the food chain is completed.