Years of punishing interplanetary labour, wiggling oneself through company politics and late nights shifts making deadline after deadline in adverse planetary climates: such was the life of Guillermo. His expertise of xenoflora at Synth Foods, micro-organisms in particular, being highly in demand sentenced him to a turbulent life always at some different end in Sirius.
The next hole that presented its self had the name “Amorgos” written over it. A moon of planet Mykonos in the Omicron Xi system where recent Corsair survey revealed a wealth of ancient alien ruins of unmeasurable price beneath the surface. This went as far as drawing the attention of a highly unusual partner: Cryer. Through lending out their highly sophisticated survey equipment and expertise subsequent and even more astounding artifacts were discovered below the surface of the moon.
The unusual business alliance was forged as for the Corsairs their supply lines were already thinly stretched. With the continuously ongoing wars with the Core, the Outcasts, and trouble brewing everywhere in the Omicrons it was calculated that the colonies at Amorgos would only last mere weeks in the case of a siege. Amorgos had the potential to be a fully autonomous colony and in doing so also highly lucrative for the Corsair home world. Paradoxically, experiencing the hardships in cultivating planet Crete first hand, the Corsairs realized they simply lacked the resources to tend to a second planet under these adverse conditions.
Cryer saw itself in the situation where the markets of the House Systems have been stagnant for decades. Though pumping its vast financial reserves in the development of new products, a rumored anti-aging drug based on Cardamine being the most prominent, any of these has of yet failed to yield substantial results. Although controversial even among the higher echelons of Cryer, a bold move was necessary: to get a foothold in the largely untapped Edge Worlds. Discoveries of new worlds promised new genetic material from alien flora and fauna. It was anticipated to revitalize the development efforts of new drugs, as well as offer a huge market full of sick people waiting to be cured. Secretly funding the colonization of Amorgos, it will be the first of many.
And so Guillermo packed his bags for his biggest task of yet. A barren planetoid with a huge workforce requiring everything from medicine, food and fresh water. And one man to figure it out with his mix of indigenous and foreign microbes.
The trip wasn’t pleasant to say the least. Cramped cabin, bad food and no window.. Penny pinching at it’s finest. They could have at least afforded me a ship of my own considering the amount of credits Synth Foods will make off me. Things were a lot better in the pilots cabin and I made myself useful just to stay there. At least the seats had some damn leg space. Lots of dicey moments too, a couple of our fighter escorts had to bail as their ships were getting toasty from radiation damage while going through the Omega systems. Gladly our armored transport had a thick hide, though our pilot nearly lost it at the sight of a dozen Titan VHF’s appearing out of no where. Must have suffered a raid or two in the past. Anyways, they made sure we traversed the last couple of system without any issues.
Amorgos is a real hellhole: dark, humid and full of noise. You are stuck in this underground hole 24/7 with no telling if its night or day. The Corsairs don’t seem to mind, or are too busy doing their thing. Everyone has two jobs: digging for artifacts and soldiering. Somehow they manage to sleep, eat and have fun in between. I can see how the stories about them surviving in the worst of circumstances are true.
With the arid conditions and scarcity of water on this planets I doubt our kelp-derivatived organisms will be any good. Not that it matters anyways. Some of the locals have sampled a couple of Synth Paste servings I brought along and grown to dislike them. It seems the Corsairs diverge from the ordinary Liberty idea that food equals mere raw nutrients, calories, and is just there to survive. They value the process of social interaction while cooking together and recreating the same dishes their mothers would cook at planet Crete when they were little. “Ancient Mediterranean culture” is what they call it and its passed down from generation to generation.
Maybe this will change overtime, who knows, I’m not a sociologist anyways to care about that. I’ve got more pressing issues: tomorrow will be my first day at work.
Given circumstances on this planet a closed loop system is the only option. Only that way can we guarantee nothing is lost and the precious resources are fully used. One of such systems is called “aquaponics”. The idea is simple: feed fish, and they will produce litter. The litter is then turned into nutrients by beneficial bacteria. These nutrients are then extracted from the water by the plants. By doing so they grow. The clean water is cycled back to the fishes. This way no hydroponic solution (such as HydroGro by Samura) is needed.
Various configurations are possible, for example the nutrient rich water can be flown through tubes in which plants grow:
The plants can also be grown on polystyrene plates which float in a basin of water (so called floating raft).
Plants can create own hydrocarbons compounds through photosynthesis, but depend on external nitrogen, phosphates and minerals-sources. The required phosphates are approx 10-20x smaller than nitrates:
The original aquaponics system can be improved for our purpose through two ways. As the nitrates are introduced in the aquaponics system through fish-food it would be beneficiary to produce this ourselves. Readily made fishfood is somewhat expensive to buy:
- “Impact of rising feed ingredient prices on aquafeeds and aquaculture production”, http://www.fao.org/3/i1143e/i1143e.pdf [… in 2008, the price of fishmeal was US$1210 per tonne. ]
While prices of phosphate and nitrogen (in the form of urea) are nearly a factor 10 lower:
It might also be possible to completely cut out the necessity of urea using nitrogen fixing plants. We will investigate this later.
Secondly the produce is not completely eaten (e.g. leaves, straws), which is a nutrient rich resource in itself. We will use compostation to recycle this and reintroduce the nutrients back in the systems.
Our aquaponics system will be modified to the one above.
Compositing also forms a backup system: in the case the fish get sick we can still continue through compostation. Multiple processes are identified and will be explored/optimized:
1. Producing fish food
2. Feeding the fish
3. Convert fish NH4 to NO3
4. Growth of crop
5. Composting
1. Producing fish food
Need to select the fastest growing plants, which preferably also fixes nitrogen from the air. This needs to be a separate system with still water and low oxygenation as oxygen deactivates the enzymes responsible for nitrogen fixation like nitrogenase reductase and thus it hampers the process of nitrogen fixation. Some of the nitrogen fixers act in anaerobic condition to curtail the level of oxygen or allow the oxygen to combine with leghemoglobin.
From “The Feeding Preferences of Grass Carp (Ctenopharyngodon idella Val.) For Ten Aquatic Plants” we get the following table:
A. Azolla
“A Review on Significance of Azolla Meal as a Protein Plant Source in Finfish Culture” describes that Azolla may be used up to 25% of the fish diet. The duckweed fern Azolla is one of the fastest growing and most productive plants on earth and thus can provide a large biomass production (https://www.wur.nl/en/project/Azolla-bio...uction.htm).
Also Azolla is nitrogen fixing: https://www.nature.com/articles/s41598-018-22760-5
"We determined growth, and N and P sequestration rates of Azolla filiculoides in N-free water at different P concentrations" E.g. growth of azolla as function of phospor, in N-free water (so the only N coming is from the air)
https://www.frontiersin.org/articles/10....00442/full
Experimental production reported here demonstrated N-fertilizer independent production of nitrogen-rich biomass with an annual yield potential per ha of 1200 kg−1 N fixed and 35 t dry biomass.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6099237/
“Growing Azolla to produce sustainable protein feed: the effect of differing species and CO2 concentrations on biomass productivity and chemical composition” confirms these numbers:
In a small production system, cultures of Azolla pinnata and Azolla filiculoides were continuously harvested for over 100 days, yielding an average productivity of 90.0–97.2 kg dry weight (DW) ha−1 d−1. Under ambient CO2 levels, N2 fixation by the fern's cyanobacterial symbionts accounted for all nitrogen in the biomass.
Proteins made up 176–208 g kg−1 DW (4.9 × total nitrogen),
Meaning yield / ha / year: 95 * 365 / 1000 = 34.675 tons DW
N2 fixation: 34.675 * 0.185 * 1 / 4.9 = 1.3 tons
For the system we are thus left with a minimal amount of artificial fertilizer, namely Phosphate:
Assuming perfect conversion (some is lost through the fish, some is added by photosynthesis at the plants), we assume 35tons of produce dry weight per ha. Most plants have a high content of water content though. Assuming 95% water content, we can produce up to 700 tons per 35 ton dryweight (=35/(1 – 0.95)) per ha. Which is more than plenty.
B. Duckweed
Spirodela oligorrhiza grown in sterile culture was able to use urea as sole source of nitrogen but only when the pH of the culture medium was below 4.3. Plants inoculated into urea media at pH 6.4 initially made little growth and became nitrogen-deficient in appearance and composition although they contained about 100 μgrams of urea per gram fresh weight of tissue. After a period the pH of the medium usually fell below 4.3 and growth commenced. Growth with other compounds, e.g. ammonium, nitrate or allantoin, as sources of nitrogen was not similarly affected by the pH of the culture medium. Urease activity could always be detected in the tissues of Spirodela oligorrhiza growing on urea. Plants with little or no urease activity soon developed significant activity when inoculated into urea media at pH 4.0. When the pH of the medium was higher there was no increase in urease activity and no growth ensued. Plants growing on urea possessed an activity of about 50 milliunits per gram fresh weight of tissue, but if the pH of the medium fell to 3.5 or lower, the activity present rose to 10 times this level. Urease activity also appeared, in the absence of supplied urea, as plants became increasingly nitrogen-deficient.
Duckweed doesn’t seem to grow much faster than Azolla (Duckweed - a potential high-protein feed resource for domestic animals and fish):
- When effectively managed in this way duckweeds yield 10-30 ton DM/ha/year containing up to 43% crude protein, 5% lipids and a highly digestible dry matter.
- Duckweeds can double their mass in between 16 hours to 2 days under optimal nutrient availability, sunlight, and water temperature. This is faster than almost any other higher plant. Under experimental conditions their production rate can approach an extrapolated 183 metric tonnes/ha/year of dry matter although yields are closer to 10-20 tons of DM/ha/year under real-world conditions (Table 1).
So the only benefit is that duckweed has a higher protein content (43%) than Azolla (30%), at the cost of using Urea fertilizer. No substantial difference in growth-speed is expected.
C. Chara
No numbers are known on nitrogen content of Chara. However it’s well liked by the Grasscarp as most of it was eaten as shown by previously quoted “The Feeding Preferences of Grass Carp (Ctenopharyngodon idella Val.) For Ten Aquatic Plants”.
Comparing to Azolla:
“Experimental production reported here demonstrated N-fertilizer independent production of nitrogen-rich biomass [of Azolla] with an annual yield potential per ha of 1200 kg−1 N fixed and 35 t dry biomass.”
And:
“Epiphytic Cyanobacteria on Chara vulgaris Are the Main Contributors to N2 Fixation in Rice Fields”
D. Combine Chara & Azolla ?
Both nitrate fixing. Will try. Probably our best bet. Also, perhaps the Chara can live below the Azolla as it does not grow on the surface of water.
E. Combine Azolla with other plants (e.g. duckweed)
Not completely as good as needs as high nitrate fixing as possible. Other plant will use Azolla’s N2 but won’t contribute.
Based upon all previous written, I will propose some of the workers here to setup a Chara & Azolla test-run. We'll see in some time how that will turn out..