10 Threats To Our Earth That Microbes Can Solve!
Updated: 7 days ago
Happy Earth Day my precious littles and welcome to Environmental Microbes 101! I am Ms. Myco Rhiza your teacher. I am so excited to be here at the Society of Symbionts to tell you all about the ways that we microbes affect this big beautiful world we live in. I was lucky enough to grow up under a beautiful tree in the Wood Wide Web where I helped giant trees grow and even talk to each other! I love growing things, it’s all so exciting and microbes are essential to ALL of the processes in nature. Unfortunately, the giants (they call themselves humans) don’t always understand how their actions affect nature and they’ve done a lot of damage to the Earth, their own home! But we can help - here are the top 10 biggest threats to the health of our planet and the many ways that microbes can work with the giants to fix them! Of course, this is more important for them; we were here before them and we’ll be here long after them - so we have to find ways to help!
Climate Change is one of the most dangerous threats that will change the course of this planet! It is caused by gases like water vapor, methane, carbon dioxide, and nitrous oxide in the atmosphere - and they are trapping heat that should be radiating from the earth into space. This is called the "Greenhouse Effect", and it has caused a rise in temperatures of 2.12 degrees Fahrenheit worldwide- it doesn’t sound like a lot, but we’ve seen an increase in droughts, heat waves, severe weather, sea levels. These and other complications are going to have long-reaching effects on the health of the earth and all of her inhabitants, including us microbes!
#1 Climate Change caused by Increasing CO2 Levels
CO2 is released as part of many natural processes like respiration and even volcano eruptions! However, since the giants moved their economy away from agricultural to production in what they call the Industrial Revolution, the amount of Carbon Dioxide has increased 47%! They burn fossil fuels to power their transportation and production, which releases a lot of CO2 into the atmosphere. But to me, the worst is that they destroy the world's precious forests with no regard to the fact that the trees and plants of the forest process CO2 into critical O2 through photosynthesis. The kicker is that the giants need O2 to survive AND keep CO2 from getting to the atmosphere!
The giants have greatly affected the Carbon Cycle, which is essential to life as we know it on this planet! In a nutshell, the respiration of plants, animals, emissions from manufacturing and cars, and decaying processes all contribute to the releasing of CO2 into the atmosphere. The CO2 then cycles back and through a process known as photosynthesis and is converted to energy for plants and other microbes that can photosynthesize, with a convenient by-product of O2, which many lifeforms depend upon; it's almost like nature knows what it's doing! However, by emitting too much CO2 and removing the forests that do most of the photosynthesizing, we end up with more CO2 in the atmosphere than there should be, which is trapping heat, contributing to the warming of the globe.
So, how do we microbes figure into it? Well, some of the CO2 from the atmosphere ends up in the ocean where photosynthetic microbes (mainly phytoplankton and Prochlorococcus [Cyanobacteria]) can 'fix the carbon', meaning they can transform it into something others can use. But as CO2 increases, the pH of the ocean decreases, increasing the acidity and decreasing carbon sequestration. All of this results in the temperature of the oceans increasing. Prochlorococcus is responsible for about 5% of the earth's photosynthesis, but only because of its best friend, Alteromonas. Under normal ocean pH, the Alteromonas shares an essential enzyme with Prochloroccus like two friends sharing popcorn at a movie theatre. But under higher Co2 levels and lower pH, Alteromonas quickly turns against Prochloroccus taking all the popcorn for herself. The popcorn in this case is the catalase enzyme. Without it, Prochloroccus can’t break down hydrogen peroxide and quickly dies. And if we lose Prochlorococcus from the oceans, we lose 5% of our photosynthetic power.
A vicious cycle, wouldn't you say? Rising temps also create an environment where MORE microbes can grow, while might be good for us microbes, some of them like Vibrio cholera can make the giants very sick!
So, what can be done to combat rising CO2 in the atmosphere that leads to rising temps? Well, the giants need to work on not emitting so much CO2 via their cars and manufacturing (I suppose they should continue to breathe, hee hee) and STOP destroying the natural systems out there that can convert CO2 so they can do their important work. How can the microbes help? Well, in 1930, biologist Joseph Hart speculated that areas of ocean surfaces that had enough nutrients but were not sustaining plankton activity were iron-deficient. Later, oceanographer John Martin hypothesized that increasing phytoplankton photosynthesis could reduce global warming by sequestering CO2. So, IronEx I, the first iron-enrichment experiment was begun near the Galapagos Islands in October 1993. Researchers found that enriched areas showed increased primary production, biomass, and photosynthetic energy conversions relative to untreated waters. So it may be possible carefully adding just a bit of iron may trigger phytoplankton blooms that will help reduce CO2 - how wonderful - great work to our brethren phytoplankton!
In other news, a team at Weizmann Institute of Science in Rehovot, Israel has engineered a strain of E. coli that uses CO2 as its sole source of carbon. So if we can create a good system to deliver it, we can use this E. coli to help remove some atmospheric CO2: bonus points if we can then use this CO2 stored in the E.coli for biofuel or in food! Isn't it wonderful that the giants and microbes are working together to help solve these problems?
#2 Climate Change caused by increased Methane gases in the atmosphere
Another greenhouse gas is Methane. While not as prevalent as CO2, it's 34 times stronger than CO2 at warming the planet! So where does methane come from? Well, lots of places like where the giants dump all of their waste in landfills, agriculture, rice cultivation, and my favorite: cow farts (hee hee).
These wonderful creatures provide a lot of the food consumed by our giant friends, like beef, milk (which is used to make cheese, yogurt, ice cream, etc.) and they also use their skin to make clothes and other useful things - so, they keep a lot of them! If all the cattle around the world formed their own nation, they would be the planet's third-largest emitter of greenhouse gases!
Another big methane source is the result of the cultivation of rice, the staple food for 3 billion people around the globe - nearly 1/5 of the calories consumed by the world! You see, rice grows in water-logged paddies which are ideal anaerobic (without oxygen) environments where methane-producing microbes love to feed on the decomposing organic matter in a process called methanogenisis. These microbes aren't trying to hurt anyone, but the sheer amount of rice being cultivated is allowing more microbes to create excess methane! Since the demand for rice is not going down, the giants are finding ways to change the processes, such as mid-season drainage to improve aerobic conditions, using plant varieties that require less water, new tilling techniques, and a more balanced application of nutrients.
How can the microbial world help? Some microbes make methane, and there are some the EAT it! We call them methanotrophs and they can convert methane into a substance called methanol - which can be used as fuel (remember the CO2 emitted by fossil fuels?) Microbes that can eat methane have an enzyme that helps break down the methane called soluble methane monooxygenase. In July of last year, Vivek Srinivas and colleagues figured out the structure of the enzyme that helps microbes eat methane! They did so using an X-ray free-electron laser or (XFEL). By studying methanotrophs the giants can better understand and invent new ways to decrease the current methane in the atmosphere!
Another exciting development is methane digesters! These are giant containers in which microbes break down organic waste. They are sealed and anaerobic so they don’t smell great, luckily we microbes can't smell! Think of it as a giant composter, the methane digester takes organic scraps and sludge and produces two useful products: biogas and digestate. The biogas can be used as an energy source and the digestate can be put back into the earth as a nutrient-rich fertilizer. The giants' trash is the microbes' feast! Project Drawdown estimates if we increase the number of biodigesters of methane digesters we can avoid somewhere between 6.2 and 9.8 gigatons for greenhouse gas emissions! Which is a billion metric tons, or a hundred million African elephants! (fun fact according to WWF we have less than half a million African elephants on earth)
#3 Climate Change caused by Nitrous Oxide
Nitrous Oxide is a very powerful greenhouse gas and also a strong ozone depleter. It is produced by soil cultivation practices (especially the use of commercial and organic fertilizers), car exhausts, nitric acid production, and biomass burning. Again, there is much less of it than of CO2, but what's there is far more powerful with one N20 molecule contributing 300 times more to climate change than one molecule of CO2! But it also has other uses, the giants use Nitrous oxide as a tool for sedation, they even call it laughing gas, but they aren't laughing about its effects on global warming!
Once again some fellow microbes are going to take some of the blame for releasing nitrous oxide into the atmosphere. One of the things microbes do as part of agriculture is a process called nitrification where microbes convert nitrogen in the soil and convert it into nitrate, with nitrous oxide as a byproduct.
See 'Decomposers' right there in the middle of the picture below? In California, one of the top agriculture states in the US, 60% of the state’s N20 emissions are from agriculture. Of course, this is a perfectly normal process, but the use of fertilizers drastically increases the ammonia available for nitrifying microbes to gobble up. It’s not so much we need to get rid of fertilizers and sacrifice our food yield in the process it’s more we need to be aware of our impact and the needs of our crops. By supplying the right type, at the right amount at the right time farmers and growers can help limit the amount of nitrous oxide being emitted into the air while not sacrificing yield. Win-win for the giants and our microbial brethren, aerobic and anaerobic bacteria and fungi!
#4 Air Pollution
Air pollution is defined as “the release of pollutants in the air that is detrimental to human health and the planet.” A big contributor to this is (again) burning fossil fuels which can cause a range of effects on people including eye and lung irritation and long-term exposure can lead to blood disorders, harm to organs, reproduction, and affect brain development, just to name a few. These pollutants can also lead to climate change and destroy the local environment. One solution is developing and using alternative methods to fossil fuels such as biodiesel, which is a fuel source that is a combination of fatty acid and alcohol and is made from things like soybean oil, recycled cooking oil, and animal fats. A big benefit is that this fuel can be used in diesel engines without having to modify them! However, there are ethical concerns about this as people feel that this is moving food availability away from the world's growing population.
This is where we microbes come in! Take algae for example; it can be grown and converts CO2 into lipids which, in turn, can be processed to make biodiesel. It is also possible to engineer microbes to produce this material. This has been achieved in E. coli, with genes to produce what is known as “microdesiel”. Although in its infancy, it replaces the fields of crops that would be needed to produce it. How exciting and a great way for microbes to contribute!
#5 Plastic Pollution Poisoning the World on land and sea
Plastic is an increasing problem in our world. One study showed that 5 companies produced 4.2 metric tons of it in 2018! 8 million tons of plastic is being dumped into the oceans annually which has only gotten worse due to the COVID epidemic as there has been a surge in single-use plastics. Many animals are harmed by plastic, birds that ingest it end up starving as it fills their stomach, straws are killing turtles and many animals can get tangled up in it and die.
Plastic also affects the giants as most plastics have toxins that can leach out like BPA, which has been linked to cardiovascular disorders. Plastics are very slow to break down and when it does it is breaking down into little pieces which are being found in the food the giants and animals eat, basically poisoning them and everything around them.
This is not a real whale, but an art exhibit that graphically shows the fate of many animals that ingest plastic and die.
A solution to this is again using microbes! In 2020 German researchers found bacteria that could break down plastic and use it as fuel. This is a pseudomonas bacteria that eats polyurethane and the researchers were surprised it survived and thrived as the plastic is generally antimicrobial. Even though this is amazing, it may be up to a decade before they can be used on a large scale so the giants still need to be better at reducing plastic usage and make sure to recycle.
One big problem is that 70% of the litter in the ocean is slow-decaying plastic. In a tiny ray of hope, scientists have found oceanic microbes that can break down plastic! They took plastic that had already been exposed to the sun and was getting brittle and put them in saltwater with either naturally occurring ocean microbes or engineered microbes that were enhanced with carbon-eating microbe strains and could survive solely off of the carbon in plastic. Scientists then analyzed changes in the materials over a period of 5 months.
The microbes changed the chemical makeup of the material, causing the polyethylene’s weight to go down by 7% and the polystyrene’s weight to go down by 11%. Perhaps there are ways we can use this on a global scale, but that will likely take many years of effort and research.
#6 Increased and Wasteful Energy Use
Over the last half of the century, global energy consumption has been increasing which makes it more difficult to transition to low carbon sources. As of 2019, the world produced over 170,000 terawatts of energy. The majority of this energy comes from gas, oil, coal (fossil fuels), and burning traditional biomasses like wood, all of which make up almost 86% of all energy production. These methods are all adding to the increase in greenhouse gasses by releasing carbon that has been sequestered into the atmosphere.
Not surprisingly, microbes can be used to make renewable energy and may help reduce waste! The method is a microbial fuel cell (MFC) where microbes break down matter and produce electrons which are then used to produce electricity just like a battery. This method has been tested on processing beer waste and
lake water processing. In fact, there are companies out there that are making this commercially available. Different microbes can do this including a group called electrogens along with Candida, Saccharomyces, and E. coli. Even NASA has used this technology. However, it still needs work on its efficiency, but it does show promise. You can even do this at home, maybe we'll try it out this semester!
#7 Loss of Biodiversity
Biodiversity is the variability of living organisms in an ecosystem. Whether you are looking at a slide under a microscope, a forest an ocean, or the giants' bodies, there are likely to be many different living things thriving and surviving – and that’s a wonderful thing! Life is complex, so complex that it takes millions of species to create the world we have today – and it’s always changing!
This diversity is critical to the functioning of the ecosystem to maintain processes such as decomposition, nutrient cycling, controlling pathogens, and soil aggregation to support plant life – they’re all connected and each piece plays its part! Wouldn’t it be boring if there weren’t all of these interesting shapes, colors, and behaviors to study? The giants are just starting to figure out that they themselves are really made up of and depend upon living microbial bacteria, which influence their health and emotions in a myriad of ways. They are starting to notice that those that are exposed to a wider variety of microbes are healthier and happier!
There is much debate about how many species are actually here on earth right now, the current guess of the macro-diversity is ~8.7 million species, although only 1.2 million have been described according to National Geographic. But it's really hard to count! Other estimates that try to take microbes into account think the number could be between 5.3 million and 1 trillion! A very wide range, but that’s because only a tiny portion of what exists has actually been discovered and documented – and we microbes are a big part of that! Why can’t they put a more concrete number on it? Well, many of us are hard to find – we can live in inaccessible or inhospitable habitats, most, like us, are too small for them to see, difficult to find, and sometimes live in other living things!
It’s actually estimated that 99.9% of all species that ever lived on Earth have already gone extinct! Many events, natural and man-made can cause massive extinction events and wipe a species off the planet, never to be seen again – sometimes they come and go and no one notices, others can cause far-reaching effects and/or lost opportunities, what if one of them could have cured cancer, provided nutrition or fixed global warming?!
All signs point to a decline of biodiversity on earth, mostly due to the destruction of habitats, pollution, poaching, and chemical interventions by the Giants. The IPBES Global Assessment Report on Biodiversity and Ecosystem Services reported to the United Nations that 1 million animal and plant species are now threatened with extinction, many within decades, more than ever before in the giants' history. this would, of course, affect the microbial world, probably by many, many millions!
The web of the world depends upon this diversity, clear to see in some ways, but so much is unknown, we can never really know all of the effects of declining diversity. We can assume there will be less food, less water, less economy, more pollution, more waste, more pests, and disease, and there will surely be less beauty and wonderful things in the world.
Finally, genetic diversity in the planetary gene pool is crucial for the resilience of all life on Earth to rare but catastrophic environmental events, such as meteor impacts or massive, sustained volcanism. If something big happens, it would take all sorts of survivors to bring life back! Many microbes will survive the most severe events, but if certain ones don't make it, the world could be in big trouble. So all we can do is stay strong and keep adapting, as we have always done!
#8 Coral Reef Die-offs
Coral Reefs are ecosystems that protect the coastlines from storms and erosion, provide jobs, are a source of food and new medicines for the giants and many other forms of life. They are also quite beautiful and are some of the most diverse ecosystems in the world, often being called the ‘rainforests of the sea’. These underwater ecosystems serve as a nursery, farm and home to untold numbers of species including plants, animals and you guessed it, microbes! The fish that live there are the main protein source for many coastal residents (human and otherwise) and they’ve also contributed to major pharmaceutical breakthroughs!
Coral reefs may look like rocks or plants, but really they are made up of tiny invertebrate animals called polyps, that grow together into a coral head. Coral has a skeleton made of limestone, which anchors it to the seafloor. In shallow water, many of these polyps form a symbiotic relationship with algae which, in turn, converts sunlight and carbon dioxide into nutrients and oxygen!
Many factors are contributing to the decline of the world's coral reefs: pollution, sediments from development, overfishing and destructive fishing practices, rising ocean temperatures, and acidity and bleaching caused by global warming.
There are more bacteria and microbes on the surface of coral reefs than the giants and there are scientists who hope to strengthen the microbiome of the coral reefs with probiotics! For example, scientists have found that a cocktail of microbes can help protect anemones from Serratia marcescens. Microbes can also help relieve the environmental stress on the corals making them more resilient to rising ocean temps, acidification, and oil spills.
#9 Loss of Tropical Forests and decreased Photosynthesis
There’s a wide belt of land surfaces around the Earth’s equator where amazing forests full of life and diversity thrive and provide for Earth’s inhabitants. These tropical forests cover only about 7% of the earth’s dry land but are home to over half of all species on Earth. Their unique climates have made way for many specialized species of plants, animals, fungi, and, of course, microbes to live! Many of these species are still undiscovered, but the giants have discovered amazing resources like delicious foods (avocados, coffee, chocolate, cashews) and spices (vanilla, sugar), and products like wood and rubber/latex.
You may not know it, but more than 25% of modern medicines originate from plants in the tropical forests of the world, some even call them the world’s largest pharmacy! Still, the giants have only figured out how to use about 1% of these medicinal wonders, imagine if they could tap into the other 99%!
These forests store carbon, absorb carbon dioxide, release oxygen, help make rain, cool the earth, help manage soil and water resources, and regulate the Earth’s climate. However, slashing and burning these wonders has occurred for many years, and despite the dire warning, it continues to escalate as the world continues to burn. Deforestation of the tropical forests to harvest wood for many products we use and makes way for crops and pastures for the food the giants eat is decimating these habitats.
In 1750, cropland and pastureland occupied 6-7% of the earth’s surface, by 1990, this has increased to 35-39%! Unfortunately, this has been done with total disregard of the consequences, including killing off entire species and driving many others to the brink of extinction including plants, animals, and microbes! That is a lot of photosynthesizers no longer pumping out the oxygen many lifeforms need as well as removing the carbon dioxide from the atmosphere! Remember, photosynthesis is the process used by green plants, algae (eukaryotic single or multicellular organisms that are neither plant, animal, or fungi), and certain bacteria to use sunlight, water, and carbon dioxide (a waste product of respiration) to create food for itself. Oxygen is a very fortunate byproduct of this process, without which this planet would be a very different place as it is a requirement for many species, which makes the destruction of the forests seem quite self-destructive! Microbes play a big role in these critical processes. It is the microbes within the photosynthesizing organism that take up CO2 and convert it to organic materials.
The future seems bleak without some major changes by the giants; there will likely be many changes to the food and oxygen supplies, to the economy, and the overall health of the planet. There’s probably not much we can do for us microbes but keep on with our part in photosynthesis and all of the other processes we do to keep things clean and moving! So many giant behaviors seem unfathomable to us. It breaks my heart to see the beautiful forests treated this way.
#10 Human Overpopulation
All of these giants on the planet keep multiplying and because they are living longer, there is a big demand for food and other goods, more than the planet was meant to provide. The giants' food industry is pretty broken; Project Drawdown has ranked the best solutions to some of the problems that this is creating. Pop Quiz! I’m going to give you four solutions to help the food industry. You try and rank them and see if you guess correctly!
a. Cook Over Clean Stoves
b. Compost Waste
c. Eat a plant-heavy diet
d. Throw away less food
d. Throw away less food (similar to taking 529 million cars off the road)
c. Eat a plant-heavy diet (496 million cars)
a. Cook over clean stoves (119 million cars)
b. Compost your waste (17.1 million cars) which is still about the number of cars California has registered
Did you get it right? Most don't, and even less of them do anything to implement these solutions in their daily lives. About ⅓ of food produced is thrown away before it gets to their plates! That's 40%, could you imagine if they could feed 40% more people on this planet! Right now 8.9% or 690 million people go hungry every day. By 2030 this is anticipated to be upwards of 840 million and by 2050 the planet will have 9 billion giants on it - that's going to put enormous pressure on the resources of this planet to feed all of these giants! If the giants would eat less meat and throw away less food, there would be fewer livestock emitting CO2, less deforestation, less production waste, and less packaging (plastic). Just a few actions would have many ripple effects that could save our world!
But how can microbes help? Through sustainable agriculture, microbes can be used to increase yield, health, and resilience among plants and protect plants from pathogens so more food can be produced to feed their increasing numbers (though maybe they should slow it down a bit)! Many plants can’t even grow without microbes! A lot of work is being done to figure out ways to grow better plants. The first patent of a bioinoculant was granted to Nobbe and Hilten in 1896 for a pure culture of rhizobia and commercialized under the product name “Nitragin”. Many things besides the giants like to eat yummy plants, so they have been trying to kill off the competition for a long time, the biopesticides industry over 100 years old! Bt toxin, a toxin produced by the Bacillus thuregiensis, was the first biopesticide to control plant pests and is still broadly used in agriculture today. In 1979, the EPA registered its first biocontrol, Agrobacterium radiobacter K84, to control crown gall.
On the helping side, prebiotics, or vitamins for microbes have been used since ancient times in the form of compost to stimulate microbial communities by enriching soil organic matter. Today, products like Biochar are used for similar purposes Biochar is the conversion of plant or animal biomass into a solid carbon-rich material that can retain nutrients and water while fostering the growth of microorganisms. These substances can replenish soils with nutrients, increase crop productivity and yield. $20 billion is spent on spreading 2.5 million tons of pesticides annually worldwide and, in turn, replacing fertilizers that increase greenhouse gases.
Whew! That was a lot! I hope you have a little more about this world and the dangers she is facing. While things are serious, perhaps if we microbes help the giants, we can turn things around so we can all enjoy the many beautiful, wonderful things the Earth has to offer all of us! Your homework is to think of how you can do your part and implement some changes, let me know in the comments section some ideas you have and how you will be helping!