Phosphorus Cycle

What is Phosphorus? 

It is an essential nutrient for plants and animals in the form of ions PO43- and HPO42-. It plays a critical role in cell development and is a key component of molecules that store energy, such as ATP (adenosine triphosphate), DNA and lipids (fats and oils). Insufficient phosphorus in the soil can result in a decreased crop yield. It is also a building block of certain parts of the human and animal body, such as the bones and teeth.

Phosphorus can be found on earth in water, soil and sediments. Unlike the compounds of other matter cycles phosphorus cannot be found in air in the gaseous state. This is because phosphorus is usually liquid at normal temperatures and pressures. It is mainly cycling through water, soil and sediments. In the atmosphere phosphorus can mainly be found as very small dust particles.



The Cycle

Phosphorus enters the environment from rocks or deposits laid down on the earth many years ago. The phosphate rock is commercially available form is called apatite. Other deposits may be from fossilized bone or bird droppings called guano. Weathering and erosion of rocks gradually releases phosphorus as phosphate ions which are soluble in water. Land plants need phosphate as a fertilizer or nutrient.

Phosphate is incorporated into many molecules essential for life such as ATP, adenosine triphosphate, which is important in the storage and use of energy. It is also in the backbone of DNA and RNA which is involved with coding for genetics.

When plant materials and waste products decay through bacterial action, the phosphate is released and returned to the environment for reuse.

Much of the phosphate eventually is washed into the water from erosion and leaching. Again water plants and algae utilize the phosphate as a nutrient. Studies have shown that phosphate is the limiting agent in the growth of plants and algae. If not enough is present, the plants are slow growing or stunted. If too much phosphate is present excess growth may occur, particularly in algae.

A large percentage of the phosphate in water is precipitated from the water as iron phosphate which is insoluble. If the phosphate is in shallow sediments, it may be readily recycled back into the water for further reuse. In deeper sediments in water, it is available for use only as part of a general uplifting of rock formations for the cycle to repeat itself.

References:
http://sciencelearn.org.nz/Contexts/Soil-Farming-and-Science/Science-Ideas-and-Concepts/The-phosphorus-cycle
http://www.lenntech.com/phosphorus-cycle.htm
http://chemistry.elmhurst.edu/vchembook/308phosphorus.html

Reaction to the 'Story of Stuff' video

The video highlights the bad effects of consumerism on the environment and on our health. I, myself, am a consumer and I have not really thought much about how the things I consume were made until I watched this video. It has awakened my awareness to how bad excessive consumption is to us and to everything around us. I learned that the production of the things I consume is a lot more complicated than I thought. Production costs a lot, in terms of money, labor, and a whole lot of consequences. I learned that because of consumerism, one-third of the earth's resources have already been consumed. It goes on at an alarming rate. And because first-world countries consume more, their resources are getting scarce so now they get their resources from third-world countries. And because production produces so much pollution, big corporations' factories are in third-world countries. I live in a third-world country. The things I consume are badly affecting my country and in the end, if this unhealthy situation goes on, I and my people will be the ones suffering the most. I do not want that to happen.


At least 100,000 toxic synthetic chemicals are being used in production. All the waste and pollution go to my native land but according to the video, we live in the same planet so everyone is affected. It comes back around. I hope corporations realize that but they are too blinded by the amount of money they are earning. The government should do something about it but corporations run the economy so the government is a slave to the corporations. It is sad that the government cares more about the economy than the actual welfare of the people and the environment. Corporations seem to control us like we are puppets. They put ads on tv, on the internet, everywhere to make us, the consumers, think that we need the things they sell even if they are not really necessary. We buy stuff either because we need them or we want them. And most of the stuff we buy are not necessities. The ads and the trends make us want to buy them. We throw away stuff that are working perfectly to buy things that go with the trends.


I learned from this video that 99% of the things we consume goes to waste. They either go to landfills or are being incinerated . Incinerators use dioxin which is the most toxic man-made substance. How much damage can we really make by just consuming way too much? There are people and organizations who are taking a stand against this vicious cycle. If we do not stop it, climate change will just get even worse. Let us not wait until it is already too late. We can do something about it if we maintain sustainability, equity, green chemistry, zero waste, closed-loop production, renewable energy and local living economies. All of these seem ideal but not impossible. We can do it if we work together with genuine will to help make a change to the only planet we have. If it dies, we all die. And we should not let it happen.