ns am a President’s Ph.D. Scholar at imperial College London. My research looks at how drilling for shale gas (natural gas trapped inside shale rock) affect both human being health and also the environment. I am also the co-Founder and also co-Director that the Amir D. Aczel structure for Research and Education in Science and Mathematics, which works to encourage young students in Cambodia to examine science and math. Ns was born on planet Day, so naturally I love gift outside and look for any excuse to invest time with pets of all shapes and also sizes! *miriam.aczel14

Young Reviewers


Age: 14

My name is Juliette and I to be a rising freshman. Ns learned just how to pat chess at an early age and also I have been playing and also competing due to the fact that then. I also love come play tennis. In addition to English, ns speak Spanish and also Mandarin. In ~ home, I have actually a hamster called Pumbaa, in referral to the warthog in Lion King.


Age: 15

ns go to high college in new York, where I spend my time composing poetry and playing the piano.



Nitrogen, the most abundant aspect in our atmosphere, is crucial to life. Nitrogen is found in soils and plants, in the water us drink, and also in the air us breathe. It is additionally essential to life: a crucial building block of DNA, which determines our genetics, is crucial to tree growth, and also therefore necessary for the food us grow. But just like everything, balance is key: too tiny nitrogen and also plants can not thrive, resulting in low chop yields; however too much nitrogen deserve to be toxicity to plants, and also can also harm our environment. Tree that carry out not have enough nitrogen end up being yellowish and do not flourish well and can have smaller flowers and fruits. Farmer can add nitrogen fertilizer to produce far better crops, but too much have the right to hurt plants and animals, and also pollute our aquatic systems. Understanding the Nitrogen Cycle—how nitrogen move from the environment to earth, v soils and ago to the environment in an countless Cycle—can aid us prosper healthy crops and also protect ours environment.

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Nitrogen, or N, making use of its scientific abbreviation, is a colorless, odorless element. Nitrogen is in the soil under ours feet, in the water we drink, and also in the air us breathe. In fact, nitrogen is the many abundant element in Earth’s atmosphere: about 78% the the setting is nitrogen! Nitrogen is necessary to every living things, including us. It plays a vital role in plant growth: too little nitrogen and plants can not thrive, bring about low crop yields; however too much nitrogen have the right to be toxic to plants <1>. Nitrogen is important for our food supply, but excess nitrogen can damage the environment.

Why Is Nitrogen Important?

The vulnerable balance of substances that is necessary for preserving life is an essential area the research, and also the balance that nitrogen in the environment is no exemption <2>. When plants absence nitrogen, they become yellowed, with stunted growth, and produce smaller fruits and flowers. Farmer may add fertilizers containing nitrogen to their crops, come increase crop growth. There is no nitrogen fertilizers, researchers estimate that us would shed up come one third of the plants we depend on because that food and other types of agriculture. Yet we should know just how much nitrogen is necessary for tree growth, since too much can pollute waterways, hurting aquatic life.

Nitrogen Is an essential to Life!

Nitrogen is a vital element in the nucleic acids DNA and also RNA, which room the most essential of all biological molecules and critical for every living things. DNA dead the genetic information, which method the accuse for how to make up a life form. Once plants perform not get enough nitrogen, they space unable to produce amino mountain (substances that contain nitrogen and also hydrogen and also make up plenty of of life cells, muscles and tissue). Without amino acids, tree cannot do the unique proteins the the tree cells need to grow. Without sufficient nitrogen, plant growth is influenced negatively. Through too much nitrogen, plants produce excess biomass, or necessary matter, such as stalks and leaves, but not sufficient root structure. In excessive cases, plants with very high level of nitrogen soaked up from soils have the right to poison farm pets that eat them <3>.

What Is Eutrophication and also can It it is in Prevented?

Excess nitrogen can also leach—or drain—from the soil right into underground water sources, or that can go into aquatic equipment as over ground runoff. This excess nitrogen can build up, bring about a process called eutrophication. Eutrophication happens as soon as too much nitrogen enriches the water, causing excessive growth that plants and also algae. Too much nitrogen deserve to even reason a lake to turn bright environment-friendly or other colors, through a “bloom” of smelly algae referred to as phytoplankton (see figure 1)! once the phytoplankton dies, microbes in the water decompose them. The procedure of decomposition reduce the quantity of dissolved oxygen in the water, and can bring about a “dead zone” the does no have enough oxygen to support most life forms. Biology in the dead zone die from lack of oxygen. This dead area can take place in freshwater lakes and additionally in coastal environments where rivers full of nutrient from farming runoff (fertilizer overflow) flow into oceans <4>.

Figure 1 - Eutrophication in ~ a waste water outlet in the potomac River, Washington, D.C.

Figure 2 shows the stages of Eutrophication (open access Wikimedia Commons picture from https://commons.m.wikimedia.org/wiki/File:Eutrophicationmodel.svg).

Figure 2 - step of eutrophication.(1) overabundance nutrients end up in the soil and also ground. (2) some nutrients come to be dissolved in water and leach or leak into deeper soil layers. Eventually, they gain drained right into a water body, such as a lake or pond. (3) part nutrients run off from over the soils and ground directly into the water. (4) The extra nutrients cause algae to bloom. (5) sunshine becomes blocked by the algae. (6) Photosynthesis and growth of plants under the water will certainly be dilute or perhaps stopped. (7) Next, the algae bloom dies and falls come the bottom of the water body. Then, bacteria start to decompose or rest up the remains, and use up oxygen in the process. (8) The decomposition process causes the water to have decreased oxygen, bring about “dead zones.” enlarge life develops like fish cannot breathe and die. The water body has actually now undergone eutrophication.

Can eutrophication be prevented? Yes! civilization who manage water resources can use various strategies to alleviate the harmful results of algal blooms and eutrophication of water surfaces. They can re-reroute excess nutrient away from lakes and vulnerable costal zones, use herbicides (chemicals used to kill undesirable plant growth) or algaecides (chemicals used to death algae) to protect against the algal blooms, and also reduce the quantities or combinations of nutrients supplied in farming fertilizers, amongst other techniques <5>. But, the can frequently be tough to discover the origin of the excess nitrogen and also other nutrients.

Once a lake has undergone eutrophication, the is also harder to do damage control. Algaecides have the right to be expensive, and they also do no correct the source of the problem: the overfill nitrogen or various other nutrients that led to the algae bloom in the an initial place! one more potential equipment is referred to as bioremediation, which is the procedure of purposefully transforming the food internet in one aquatic ecosystem to mitigate or control the quantity of phytoplankton. Because that example, water managers deserve to introduce organisms that eat phytoplankton, and also these organisms can assist reduce the amounts of phytoplankton, by eating them!

What specifically Is the Nitrogen Cycle?

The nitrogen cycle is a repeating bike of processes throughout which nitrogen moves with both living and non-living things: the atmosphere, soil, water, plants, animals and bacteria. In bespeak to move through the various parts the the cycle, nitrogen must adjust forms. In the atmosphere, nitrogen exists together a gas (N2), yet in the soils the exists as nitrogen oxide, NO, and nitrogen dioxide, NO2, and when provided as a fertilizer, deserve to be found in various other forms, such together ammonia, NH3, which can be processed even further into a different fertilizer, ammonium nitrate, or NH4NO3.

There are 5 stages in the nitrogen cycle, and also we will now talk about each of them in turn: permanent or volatilization, mineralization, nitrification, immobilization, and denitrification. In this image, microbes in the soil rotate nitrogen gas (N2) into what is dubbed volatile ammonia (NH3), for this reason the fixation procedure is referred to as volatilization. Leaching is where specific forms that nitrogen (such together nitrate, or NO3) becomes dissolved in water and also leaks the end of the soil, potentially polluting waterways.

Stage 1: Nitrogen Fixation

In this stage, nitrogen move from the environment into the soil. Earth’s atmosphere consists of a substantial pool that nitrogen gas (N2). But this nitrogen is “unavailable” come plants, since the gaseous kind cannot be used straight by tree without undergoing a transformation. Come be used by plants, the N2 should be transformed through a procedure called nitrogen fixation. Fixation counter nitrogen in the environment into creates that plants have the right to absorb through their source systems.

A small amount the nitrogen can be fixed once lightning offers the power needed for N2 come react v oxygen, producing nitrogen oxide, NO, and also nitrogen dioxide, NO2. These creates of nitrogen then enter soils with rain or snow. Nitrogen can also be resolved through the industrial process that creates fertilizer. This type of solving occurs under high heat and pressure, during which atmospheric nitrogen and hydrogen are linked to kind ammonia (NH3), which may then be handle further, to create ammonium nitrate (NH4NO3), a form of nitrogen that have the right to be included to soils and also used by plants.

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Most nitrogen fixation wake up naturally, in the soil, through bacteria. In figure 3 (above), you deserve to see nitrogen fixation and also exchange of type occurring in the soil. Part bacteria connect to plant roots and have a symbiotic (beneficial because that both the plant and the bacteria) connection with the tree <6>. The bacteria get energy through photosynthesis and, in return, they fix nitrogen into a form the tree needs. The resolved nitrogen is then lugged to various other parts of the plant and is used to form plant tissues, so the plant have the right to grow. Other bacteria live openly in soils or water and also can solve nitrogen without this symbiotic relationship. These bacteria can also create develops of nitrogen that deserve to be provided by organisms.