Phytoremediation - A Good Deed

A while ago, when reading the 1000GoodDeeds.com post “Good deed #6: Plant a Tree”, a topic came to my mind, and I thought it would be interesting to share it with all Muslimness community.

For all of those who are still asking themselves why planting a tree may be considered as a good deed, the reasons are quite simple: plants and trees are very pretty, don’t you think? They beautify the streets, they provide a nice cool shade on really hot days, some of them smell nice, and when they bloom they are truly a pleasure to see. But plants can also be helpful because they take good care of us, in their own unique and wicked way. If you do not believe this, I hope by the end of this article you will have changed your mind.

Most plants help us in getting rid of the so feared carbon dioxide (CO2), a gas that is very well known for its pernicious effects on the atmosphere: along with other gases it creates the “green-house effect”. In simple words, these gases form like a tent which lets sunlight pass through, but it doesn’t let that energy escape back out into the space; in present times this is causing a raise in the temperature all around the world.

Perhaps you are already wondering how a plant get rids of this gas. Plants actually get their energy from sunlight to break down molecules of carbon dioxide and water to transform them into glucose, more water, and molecular oxygen. Plants have the ability to convert photons (energy units of radiant energy, yes they come from sunlight), first, into a flow of electrons and, ultimately, into chemical energy (glucose and other molecules). This process is known as photosynthesis.

If it wasn’t because of these green creatures, life as we know it would not even exist: there would be no molecular oxygen in the atmosphere, and this gas is absolutely necessary for the respiration process of most living things; carbon dioxide would not be degraded and transformed into other substances, so it would accumulate in the environment, and this would mean the death of many living organisms; add to that that plants are the main source of food all over the planet. The glucose and other starches present in plants are carbohydrates, which provide other organisms with the energy necessary for their sustenance.

Turns out that Greenpeace was right, plants and trees are not only the lungs, but also the main producers of food and other primary materials all over the planet. But I have to say, these are not all the abilities these green beings can show: they are real masters in taking care of the environment, and they do this by getting rid of a great variety of polluting substances.

I’m pretty sure you’ve heard of hardcore pollution events, for they have been widely publicized by the media whenever they occur: massive oil leakages due to “human mistakes” that could have been prevented; mining activities which impoverish the quality of the soil, and cause a great variety of diseases within the people living in the near areas, and the alarming raising on the amount of contaminated water. Yes, everybody talks about how did it happen, and what damages will it be causing; but anyone has the slightest idea of how can it be solved? Oh yes, super plants come to the rescue =]

There is a new way of taking care of these situations, and it is called phytoremediation (phyto means plant). This is an interesting group of different technologies which actually use plants to clean and “heal” polluted soils, sediments and water. Depending on the needs of the soil or water and how polluted they are, plants take up to a few decades to efficiently get rid of the polluting substances, reducing them to levels that suppose but little harm to the environment and to the health of the people who live near the affected areas. Some of you might already think that a few decades is a lot of time, but compare it to the centuries it would take nature to regenerate itself in the actual conditions… I think decades are acceptable.

(Download a two-page Citizen's guide on phytoremediation)

This whole cleaning process can be divided in two main stages: the identification of the polluting substances and then the process of remediation. On the first stage the polluting substances are identified as I already said, and scientists also take on with studies to reveal the amount, concentration and level of toxicity of these. On the second stage another kind of identification takes place: it is the turn for the plants. Expert biologists and botanists search and identify potential candidates to be used as cleaners.

For plants to fulfill the requirements to be used as phyto-remedies they must have been born in the contaminated area, they must be fully adapted to the local weather, also they must present certain changes in the structure of their roots and leaves which indicate that they have adapted to their new life conditions. On top of all this, they must be very strong and resistant, because they will be exposed to intense levels of toxicity. They are taken from the place where they grow and then they are raised in a green house. When they start reproducing, a series of experiments intended to test to which contaminants they are resistant are held. If they can resist the prolonged exposure to all these substances then it means they can be used out in the polluted areas. Once plants are set in the right places, they will start absorbing, transforming and degrading pollutants, which can go from hydrocarbons (like oils and refined products of it) to highly toxic metals, a result of excessive mining activities.

Most plants end up dying during this process due to the high concentrations of toxic substances to which they are exposed, so scientists and inhabitants of the near areas have to continuously work to replace them for new plants; if those plants die and decompose then the substances will return to the soil, so they also have to remove them as soon as they begin to die. It is a hard task, but so far it has yielded great results.

When it comes to the water, it depends on how contaminated the water is. For example, in the beaches of Spain, where years ago there was a massive disaster because of the leakage of oil from a transporting ship into the ocean, scientists have been using living organisms to degrade this hydrocarbon and clean the beaches. They estimate it might take a few years to go almost back to normal, and they are confident that the use of this plants and bacteria will eventually help the environment in this task.

As you can see, plants by themselves can be quite helpful, but if you combine them with other purification methods, they give great results. In my university, for example, all the water from the toilets goes to a couple of huge reactors, which contain a great amount of bacteria. Don’t panic, these bacteria are rather helpful: they help degrade feces and urine, turning them into other substances which can be easily separated from water. After this process, the water goes through containers which contain soil and plants.

The soil is very much like the minerals used to filter the water, and the plants also help in this task; they both end up cleaning the vital liquid, which is finally taken to other containers in which chlorine is added, to kill all pathogen bacteria (pathogens cause diseases). This water is used again for watering the plants within the campus, and to flush the toilets. I have to say the purification process is very effective; a few years ago they used to use treated water to irrigate the grass in the campus, and they used to do it during the night, when the campus was left alone, the reason… the smell was like that of an open sewer. Now they can water the plants at any hour of the day, and the smell has disappeared =D

If all these reasons are just not enough, I could keep on writing how plants can be used for producing medicines, they can be used to make textiles and so many other things we use in our everyday life; but I think I would never finish!

So next time you see a plant, make sure you don’t underestimate it, they are Allah’s creation, therefore they are wonderful.