Eutrophication Explained - Lake Harding Association

Eutrophication Explained

Eutrophication Explained

By Micah Moen 52 Comments August 13, 2019


[birds chirping, water flowing] [music] Plants require several things to grow.
Most of us know that they need things like water, sunlight, and CO2, but plants also need a variety of nutrients as well: things like nitrogen and phosphorus. Usually, plants will get all the required nutrients from the soil through their roots. But, when the soil is bad, or there’s been a lot of erosion or leaching, farmers–or even just people trying to make their lawns green–will put down something called “fertilizer.” What makes fertilizer so “fertile” is that it’s been enriched with these nutrients that the plants need–again, mostly fixed nitrogen and phosphorus. But plants aren’t the best at soaking up every last nutrient in the soil, and it’s also hard to gauge just how much fertilizer a field needs, as soil quality can vary drastically over short distances. To be safe, farmers will usually apply excess fertilizer to a given plot of land. Better safe than sorry, y’know? But, instead of staying in the soil for years, most of the excess nutrients will be carried away by the rain or other forms of irrigation. These nutrients mix with the water and find their way into bodies of water–like ponds, lakes, reservoirs, and even the oceans sometimes. With all these nutrients added, the algae, phytoplankton, and even plants in the water do the same thing the crops in the field do: they grow. Well, actually they *explode* in numbers. This is called an “algal bloom,” and entire lakes can become covered in layers of plant growth like this. To some, this might seem like a good thing. Plants are good for the environment, right? Well… not always. First off, this floating layer of algae forms basically an impenetrable roof on the water, not allowing sunlight through to the bottom of the lake. Without the presence of sunlight, all plants below the surface cannot partake in photosynthesis– You know–metabolize, make glucose, live, that sort of stuff? But, not even this is the bad part of it all. Many plants can store enough energy in their bodies to wait out these conditions. The real problem comes when all the nutrients are used up and the water can no longer support so much life. When this happens, the excess algae, phytoplankton, and plants die off and sink to the bottom of the body of water. Here, bacteria and other decomposers feast on the dead bodies in a chemical process of decay which consumes oxygen. Now, in a usual ecosystem the amount of dead matter is relatively constant, so oxygen levels stay relatively constant as well. But, when a bloom occurs, far more organic matter is ready to decompose, and so nearly all the oxygen in the water is used in the process of decomposition, and none is left for the animals living in the water. Without this, animals that use the dissolved oxygen to breathe (so, things like fish), can actually suffocate. This causes even more death, leading to more decomposition and more oxygen usage. Basically, at this point, a positive feedback loop has been created. It can take a body of water a very long time to recover, though each one is different, and recovery depends on a lot of things, like: how many nutrients leaked into the water, how big the body of water is, what organisms are present there, and so on. When this happens in lakes, native species can be suppressed and allow invasives to come in while the environment is still disturbed. If this happens in the ocean, the lack of oxygen can cause corals to bleach and possibly even die. All around, this can greatly damage many ecosystems and leads to a decrease in biodiversity globally. Nutrient-rich runoff can also be caused by things like clear-cutting (which releases the nutrients which were kept in the soil by the plants) or also by things like animal farms (where nutrient-rich waste materials can leak into local bodies of water). And that’s eutrophication, simply put! I hope you enjoyed the video and maybe think twice before using fertilizer or clearing a forest. If you want more people to see this video, give it a like, and if you want to see more videos like this, subscribe to this channel. I’ll be back next week with another one… Thanks! 🙂

52 Comments found

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nicked011

Great, keep going man!

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Ed Jones

Great video as always. Congrats on 1K subs by the way!

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מיכאל ניצן

I need you to get more views already, so i showed you to a few of my feiends. Btw great vid

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Integza

Amazing job condensing information into such a short and enjoiable video. You truly inspire me to do better .

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Intellectual Magician

Seriously, where was this channel and all its concise explanations when I was failing my environmental science course last year?

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Andrew Ditcharo

#stopusingfertilizer

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Marco Naujokat

Your graphics are improving by leaps and bounds! I love the floating molecules on the river .

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Arnhûr Belegrin

Here in Mexico City, Chapultepec lake is always green so I guess there is no animal or vegetal life :'v, also because of the boats sailing all over. Anyhow congrats for the 1000 subscribers, your channel deserves a LOT more 🙂

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Mudd Rosal

Does Eutrophication tend to happen naturally in nature (perhaps a forest fire?) or is it almost always a human condition?

Yet another great video btw. I don't tend to gain a lot of new information from youtubers, but your concise videos always seem to carry information peripheral to my world knowledge. Keep it up!! 🙂

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Andrew Ditcharo

Hey I know I already commented but you should make s discord server

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Helai

Wow, this is really good! It has all the important information and it's condensed so well.

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Abhimanyu Sharma

Thankyou so much!
Tommorow is my environmental ecology exam..this helped me😁👍

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David kun

well explained 👍👍

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Parth Kelawala

Very well explained thank you

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suhana singh

awsm

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Anu Pathania

Cool

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Alyssa Frobase-Reynolds

Farmer’s actually have their fields tested throughout the entire field before applying, and only fertilize in the deficient areas. Fertilizers are expensive, especially when you are talking about hundred of acres. So as a farmer, no better be safe than sorry is not true – I don’t want to waste my money.

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mroldnewbie

This was to the point, great video.

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Order of Azarath

That one cow to the very right xD

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RuneBlu

They should show these videos in schools!

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ruu

10/10 nice job man

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Green Ghouls

"Mostly FIXED nitrogen and phosphorus" But you show elemental nitrogen and phosphorus?

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WisdomThumbs

And this doesn’t even take Round-Up or other harmful chemicals into account. But that’s enough of a topic for a video in itself.

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YellowBanan

This video would have been helpful with my uni paper, but I guess its nice to watch your videos and actually know beforehand

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Carlos Carreño

I cant believe I haven't seen this channel before, the videos are great in quality

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HansLemurson

"Fixed" Nitrogen is not N2 molecules, it's Ammonia or Nitrate. Phosphorus used by plants is in the form of Phosphate. Plants use Oxidized forms, not the ELemental form!

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misomalu

That’s why it’s a good idea to throw your old car batteries into the ocean.

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James Christopher Cirujano

Will still use fertilizer though since there is no body of water near our place except the one near a massive river, I'm guilt free.

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Gabryel Steinmetz

Well I guess I won't be clearing a forest this Saturday

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its Mel

We was talking about eutrophication in science class

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Manoj Kumar

Effective

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Educational Account

But what is eutrophication?

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Joe Miller

Great video! we learned alot (just not spelling)

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Pendlera

A huge source of runoff that you didn't mention is grass clippings. When people dump unbagged grass clippings on the side of the road, they wash into the sewers and decompose, leaching all of the nutrients used to grow them. http://renegadegardener.com/care/every-curb-is-a-shoreline/

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RELANDREL

wow
"positive" environmental actions in the short term leading to super negative later

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Drako Von Zeitgeistoberstellen

Japanese EM tech is the solution to this! Right?

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SOX Shimoneta

Now Vegan activists Take that. You plant eaters wanted to make the problems modern irrigation does to the environment.

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Poulomi Hari

Can ducks be used to prevent Eutrophication. In my country a eco-scientist has developed an eco-friendly waste management model according to which we use ducks to clean lakes and ponds. He says that the ducks paddle so fast, they help in keeping the water clean.

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FirstRisingSouI

Wait, so, as someone who has never heard the word before, exactly which part/collection of the processes discussed is eutrophication?

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Hexasgone

In Pakistan we have a 40 meter lake that formed 6 months ago it's still not dried even now when it's summer the plants are way above it

Also it's a artificially created lake

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Martin Zapata

Hi mrs teacher you awesome

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Dexter André Osiander

3:23 The cow on the right is like "Do you mind not filming? I can't eat with people watching…"

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Dhiren M

3:25 wow .are those cows chained or is it like a guide for their head ?

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Jane Doe

THANK YOU – sharing on FB

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Gina Stiehl

well explained, thank you. Now I can get back to my assessment…

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Ian Smith

I always found it funny how people rake away leaves and grass clippings and then put down fertilizer.
It’s like not drinking water and then hooking yourself up to a saline drip.

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Atomic Reverend Alexander

The fertilizer bag you show has no phosphorus in it… the 24 is the nitrogen the 0 is the phosphorus and the 11 is the potash.

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Vered Leffler

But if I am fertilization (as a human being lying down for a loooooong time) then suiciding at a lake is not a responsible thing to do?

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PuffMaster 1517

Me dumping fertilizer straight into a lake: Y'all hear something?

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Billy Gundum

Can we use algae to feed land plants and soil?
Why?
Or
Why not?

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new things with Joey

thank you I will give u my gcse if I pass now xxxxxxx

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Zhu Bajie

Also, don't forget the stupid useless lawns that people overfertilize (the U.S. largest crop).

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