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The first official model of the LifeJar will be released September 20, 2020.

Steady-State Systems and Ecological Models: Essential Hobbyist knowledge

In steady-state systems, the amount of input and the amount of output of various processes, functions and matter within the ecosystem are equal. A steady-state is a balanced state, sometimes called homeostasis. In the context of LifeJars or Closed Ecological Systems (CES's) I view it as a goal. If built properly, the self-organization and self-balancing (called Succession) of the ecosystem will be successful and a steady-state will be achieved.

Succession will occur in any LifeJar, CES, or microcosm but a steady-state is not guaranteed. An example of balanced inputs and outputs of one aspect of an ecosystem is respiration. When Photosynthesizing plant's or algae's Oxygen production matches that of the Oxygen consumer's needs, who then respire CO2 back to the plants (CO2:O2 happens to be traded in 1:1 ratio in aerobic respiration) this represents an equalized input/output of a process. (As a side note: It just so happens that aerobic respiration input/output is a good indicator of overall ecological stability, the closer to 1:1 the better.(1))

A steady-state system takes into account processes and rates of things like life/death, plant mass produced/ dead plant matter produced, phytoplankton grown / grazer consumption, and even nutrients taken from soil and those returned to the soil. All of the inputs and outputs of all these different processes and functions occurring within an ecosystem can easily become confusing. So scientists created Ecological Models in order to illustrate them.



A CES can be modeled. Like that one, it is only modeling the production/respiration of a Closed Aquatic Microcosm. Ecological Models can be simple or complex and very useful tools to understand complex relationships where it might be hard without a visual aid. A model contains compartments, of a certain shape signifying things like total waste, total oxygen, total food, total organic matter, plant/bacteria biomass or any number of typically physical things. A model also contains processes like "Decay", "Respiration", "photosynthesis", "defecation", "Daphnia Grazing". The different shapes will signify something different, perhaps more complex interactions, for example: mathematical functions, amplification, switching, or heat loss.

Each scientist decides what the shapes mean. One may make all organisms prey or predator as rectangles or divide consumers and producers and predators and prey and give each group their own shape. It all depends on what the scientists wants to model. He/she will design a model with the goal of making it illustrate what she/he wants in the easiest to understand way. That's the whole point. Like looking at a map of a city, with it's major streets and avenues and hot spots and how that gives you a better idea of the city as a whole and how it kinda, "works", it's sort of the same with Ecological Models, they give you a better idea of the whole thing and how it works.

Instead of illustrating the ecosystem by drawing all the separate plants, a model may contain a single box dedicated to all "plant biomass" or even simpler "organic storage" indicating all organic matter within the CES. Take a box representing "Plants" for example, that box might have a "flow" arrow indicating light going to the box, with the "light" compartment/box labelled "energy" or "light" with an energy level equation, that plant biomass compartment/box may also have other "flow" arrows coming in and going out of it. These "flow" arrows moving to and away from different compartments or shapes signifying different things are the inputs and outputs of the system. An important thing to be able to understand as that is precisely what a system that has achieved a steady-state has to do with.

Models aren't just a way to model steady-states, you can have multiple models of a single ecosystem, depending on what you want to illustrate. It's a complex system and sometimes you just want to break down a few aspects at a time. Like a few I linked above, one was just respiration and one was even simpler than that.



When anyone first builds a jarrarium or CES, these inputs and outputs from one compartment to the next aren't balanced or equalized. You'll have more oxygen consumption than produced or vica versa, you'll have more plant growth than dead plant matter buildup or vica versa, more phytoplankton consumed than produced, more new life than death, more death than new life. Etc. Etc. Etc.

Take a look at this model Here and using your imagination for a moment, pretend that that ecological model is like a factory of looping conveyor belts creating a kind of assembly line, putting life together, breaking it down, and putting it back again in a loop of moving resources around on "conveyor belts" to and from boxes, called "compartments", which are simply a representation of the total amount of "x", "y" or "z" in the system, (not a literal compartment). In these unbalanced systems, or, "unconfigured assembly lines" you might have a resource in a compartment being "drained", that is, the output conveyor belts are moving more quickly than the input conveyor belts and our storage of that resources is shrinking (Ex: Loss of usable Nitrogen nutrient for plants due to reduction to unusable form and not replenished), and you'll have bottlenecks, the opposite of draining...Conveyor belts moving something into the storage box (box here just means the overall amount in system) more quickly than the output conveyor belts are removing it from that storage. (Ex: Methane build up from anaerobic activity not being broken down as quickly as it's being produced).

Organizing these things into compartments like "organic matter" or processes like "photosynthesis" allows us to view the complexity in a more palatable way. (And I really like my factory analogy). Ok, I promise this is the last time, I'll ask you to look at this model: https://i.imgur.com/Y9uwZ1Y.jpg but before you do imagine these scenarios: Imagine there was too much light what would happen to the next compartment in line (algae)? Would it cause a drain or a bottleneck in that compartment (compartment = algae population)?

Answer: In that case the "conveyor belt" is moving too fast into the algae compartment (light->algae) and for a time the output conveyor belts aren't equalized so you're going to get a build up. What does that mean? You are providing increased light to algae, the algae's population will grow. The self-stabilizing takes place when the population of the algae consumers slowly start to rise because of the food surplus, this in essence, "speeds up" the output conveyor belt which will eventually equalize to the same "speed" as the input conveyor belt. Achieving homeostasis in the predator-prey cycle, but not necessarily steady-state because it's not system wide... Same principle though, equalized inputs and outputs.

Look at my Model Here and see if you can figure out what would happen if you increased/decreased certain inputs or increased/decreased certain outputs in different places in the ecosystem. Try to think what would happen to the ecosystem. Remember, food surplus leads to population growth, food deficit leads to population decline and follow the conveyor belts with your adjustments to them.

If these misconfigurations in the input/outputs and other imbalances (perhaps excess nutrients) do not correct themselves on their own, it could lead to a flawed system doomed to be unhealthy and sick, or dead all together. That is why good design of a LifeJar or CES is important. But nature, uh, finds a way. No, really. These systems are pretty amazing at self-stabilizing and self-balancing themselves with a little guidance.

I know I've discussed imbalances in a CES and what that would look like in a model and I defined what a steady-state is. Is that enough? I'm not sure. Click and open https://i.imgur.com/ciQ09ix.png and I'll briefly go through what a steady-state might look like. You want to start at the source, light, everything will get it's energy from this light, if not directly, through the food chain, which cascades that energy up trophic levels. Light we keep steady, that's very important, finding the correct balance there depends on many factors and is beyond the scope of this article. Light feeds the primary producers which take light and raw nutrients and form it into the first level of organic matter that can be eaten. In this case, by snails and daphnia. I'll spare walking you through the whole thing. There's no need, the point of my model is to be easy to understand. I hope it is! I will tell you what the system pictured here will have to attain to be considered in "homeostasis". When

1) Aerobic respiration ratio is near 1:1 ratio production:consumption (plants/animals)

2) When the population of Daphnia has stabilized to be consistently sustained by their food source (phytoplankton)

3) When the snail population has been stabilized to be sustained by their food source (algae)

4) When daphnia/snail's food sources phyto and algae growth has stabilized (not overgrowing, typically stopped by a limiting factor, specific nutrient, CO2, etc) The relationship between daphnia and phyto and snail and algae (and daphnia and algae) will not achieve perfect balance. The Daphnia/Phyto dynamic will oscillate wildly and would be stupidly unstable, but this is an example and in this example, in order for that steady-state to be achieved daphnia and phyto populations would have to predictably oscillate.

5a) When microbial population has stabilized in accordance to their food supply

5b) When microbial populations have enough oxygen (back to #1) and don't go anaerobic. Anaerobic respiration can take many forms and most are toxic and harmful and are quite counter productive to a steady-state system.

6) When nutrients in the soil are replenished at the same speed they are taken up by plants or leached out into water column (then utilized by algae). This is accomplished by slowed growth of the algae/plants along with normal plant/algae shedding, general decay, and leaf death contributing to detritus that will return the nutrients to the soil. In addition if you look at the eco model you can see that Daphnia and snails eat phytoplankton and algae and their waste containing the nutrients the plants took up will be deposited as their waste.

7) When overall life and death is equal and the jar has been observed to be stable, nothing crazy like algae outbreaks, or extinctions, or melting plants or toxic gas you know, nightmarish things.

8) As you can see, I'm simply going through all the compartments and then making a number for every input or output. And essentially saying "ok this input/output relationship has to be equalized".

That's the kinda thing you want to see in a steady-state, and above that that's how an unbalanced CES model would "flow". My long 1-8 explanation of how to tell if a CES is in steady-state is a great example the benefit of a visual model. Perhaps it's just me? I am a visual learner, but looking at that model tells me a lot of information and I find it more efficient than reading half a page. But as you can see, the reason why I emphasized ecological models so much is because of how crucial they are to understanding steady-state systems. I hope I've proven they can be a useful tool.

**Remember: In a CES that's reached a steady-state there are no imbalances, "drains", bottlenecks or "hiccups" in the "ecological factor assembly line".**

This is very much related to steady-state and especially pertains to CES's:

"Alternative stable-state system theory which predicts that ecosystems can exist under multiple "states" (sets of unique biotic and abiotic conditions). These alternative states are non-transitory and therefore considered stable over ecologically-relevant timescales. Ecosystems may transition from one stable state to another, in what is known as a state shift (sometimes termed a phase shift or regime shift (2), when perturbed. Due to ecological feedbacks, ecosystems display resistance to state shifts and therefore tend to remain in one state unless perturbations are large enough. Multiple states may persist under equal environmental conditions, a phenomenon known as hysteresis. Alternative stable state theory suggests that discrete states are separated by ecological thresholds, in contrast to ecosystems which change smoothly and continuously along an environmental gradient. " (3)

Alternative stable-state theory are more likely to be observed in CES's because of their small and delicate nature, both those adjectives I suppose go hand in hand. I say delicate because unlike an ecologically robust, geographically large, and long-stabilized ecosystem of say, a rain forest, a small CES is much more susceptible to disturbances and imbalances making the ecosystems within them far less ecologically resilient (4), and therefore, more vulnerable to alternative stable-state hocus pocus.



Indeed, I would make the argument that the oscillations experienced in a system that has achieved a steady-state is the same as a system experiencing alternative stable-states. The steady-state accompanied by oscillations within it will be observed in all successful microcosms to varying degrees. Just goes with the nature of them, only difference will be the duration of time between oscillations (and what form they take). A microcosm with Phytoplankton and Phyto grazers would experience much more frequent oscillations in the predator-prey cycle whereas a microcosm with a single slow-growing plant may experience oscillations that are on a much longer scale (to the points where I'd question if you can count it as an oscillation even if it does repeat itself.)

Putting It All Together:

You want your system to enter into a stable-state, which is when all the compartments have equalized their inputs and outputs with all other compartments, there are no bottlenecks, deficits or "leaks" that can't be replenished. You want a steady-state system in which the model's diagram flows like a smooth conveyor belt factory carrying energy and matter as efficiently as possible to and from all compartments in what is essentially a closed loop* of life assembly, disassembly, and assembly again ad infinitum. To gauge if your CES is in a steady-state, you must have the ability to measure aerobic respiration within it, if the ratio of production and consumption is close to 1:1. You can have some confidence that it has achieved homeostasis (steady-state). Furthermore, if it reaches a steady-state, or, homeostasis, it's only until that point can it be considered to be the closest it'll get to a truly self-sustaining ecosystem.

Personally though, I will feel comfortable declaring homeostasis no sooner than a year of a CES's life. In the few months leading up to it's one year birthday if I see balance, if I see no decline, nothing surprising and only predictable and familiar oscillations I will then feel very confident in the steady-state.

To help your CES achieve a steady-state faster DO NOT MOVE IT AROUND A LOT. Changing how much energy the CES is getting can have huge impacts on the sensitive ecosystem within it. Pick a spot and leave it. Do not underestimate how big of an impact this can make. Likewise, any other environmental conditions. Keep it in a nice stable location without extremes of light, darkness, heat, cold, or loud Nickleback music.

An Ecological Threshold: is the point at which a relatively small change or disturbance in external conditions causes a rapid change in an ecosystem. When an ecological threshold has been passed, the ecosystem may no longer be able to return to it's state by means of it's inherent resilience.

Our CES are very sensitive. A steady-state can easily be lost and ecosystem destroyed. Remember, a CES isn't necessarily more resilient once a steady-state has been reached. In fact, it's in a very delicate balance in order to maintain the steady-state everything has to be working properly in this "ecosystem factory". A steady-state where all inputs and outputs of the entire system are equal? That's hard to achieve, and took a while too self-organize such a thing hangs in a delicate balance. Light, Dark, Heat, Cold the things you can control about it need to be kept as stable as possible. It literally self-organized around those variables. Light's the most important one to keep stabilized though. While mine deteriorated when exposed to Nickleback when I played "Higher and Higher" my CES's plants started to sway and the jar jumped up and down like the toaster in Ghost Busters II.



*Note: Closed Ecological Systems will never be closed loops because these are never truly closed systems. They are only "closed to matter" systems. Light comes in which provides the initial energy to the primary producers (ex:Algae) and in very minute amounts heat is produced (ex:organism metabolism and chemical reactions) which diffuses over time and eventually exits the system.



Light goes in, heat goes out.

That line can be applied from small CES's to large ecosystems all the way up to the entire Sun-Earth "Ecosystem" as a whole -the same line applies in all three examples and everywhere in between. While I admit, the line is rather...crude and simple, it's simplicity lends itself to a broader understanding.



And to me, there's something special about that, something humbling in a way, something that gives me a feeling as if I am able to see, even if it's only with a crudest glance, a simplified order to the immense complexity that is the web of life on Earth, and it's relationship to the cosmos and how I can hold a miniature ecosystem in the palm of my hand and somehow feel connected to the whole thing.

References/Links:

1: Respiration as indicator of Ecological stability.

2: Regime Shift

3: Alternative Stable-state Theory

4: Ecological Resilience

5: Ecological Threshold

6: Beyers, Robert. Odum, Howard. Ecological Microcosms. Springer-Verlag, 1993.

7: Ecosystem Models

8: Thermodynamic Equilibrium

9: Homeostasis

10: Ecological stability