Chemical Fertilisers

7/29/2019 Chemical Fertilisers

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CHEMICAL FERTILISERS

WHAT ARE CHEMICAL FERTILISERS?A chemical fertilizer is a substance applied to soils or directly onto plants to

provide nutrients optimal for their growth and development. The essential

nutrients contained in these fertilizers are nitrogen, phosphorous, and potassium

(NPK), as well as other nutritional substances in

smaller amountsall presented in a form that

can easily be absorbed and metabolized by

plants. Chemical fertilizers have become a staple

in many yards and gardens, and can be a key

component of a healthy lawn care routine. Read

on for some basic information on chemical

fertilizer and how you can use it most effectively

in your yard. Fertilizer is any organic or

inorganic material of natural or synthetic origin (other than liming materials)that is added to a soil to supply one or more plant nutrients essential to the

growth of plants. Conservative estimates report 30 to 50% of crop yields are

attributed to natural or synthetic commercial fertilizer. European fertilizer

market is expected to grow to 15.3 billion by 2018.


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WHY DO PLANTS NEED FERTILISRS?In order for a plant to grow and thrive, it needs

a number of different chemical elements. Themost important are:

Carbon, hydrogen and oxygen - Availablefrom air and water and therefore in

plentiful supply

Nitrogen, phosphorus, potassium (a.k.a. potash) - The three macronutrientsand the three elements you find in most packaged fertilizers

Sulfur, calcium, and magnesium - Secondary nutrients Boron, cobalt, copper, iron, manganese, molybdenum and zinc -

Micronutrients

The most important of these (the ones that are needed in the largest quantity by a

plant) are nitrogen, phosphorus and potassium. If you have read the articlesHowCells WorkandHow Food Works, you have heard about things like amino acids,

cell membranes and ATP. Nitrogen, phosphorus and potassium are importantbecause they are necessary for these basic building blocks. For example:

Every amino acid contains nitrogen. Every molecule making up every cell's

membrane contains phosphorous (the

membrane molecules are called

phospholipids), and so does every molecule ofATP (the main energy source of all cells).

Potassium makes up 1 percent to 2 percent ofthe weight of any plant and, as an ion in cells,

is essential to metabolism.
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Without nitrogen, phosphorus and potassium, the plant simply cannot grow

because it cannot make the pieces it needs. It's like

a car factory running out ofsteelor a road crew

running out of asphalt.

If any of the macronutrients are missing or hard to

obtain from the soil, this will limit the growth rate

for the plant. In nature, the nitrogen, phosphorous

and potassium often come from the decay of plants that have died. In the case of

nitrogen, the recycling of nitrogen from dead to living plants is often the onlysource of nitrogen in the soil.

To make plants grow faster, what you need to do is supply the elements that the

plants need in readily available forms. That is the goal of fertilizer. Most fertilizerssupply just nitrogen, phosphorus and potassium because the other chemicals are

needed in much lower quantities and are generally available in most soils.

Nitrogen, phosphorus and potassium availability is the big limit to growth.

How Does Fertilizer Work? There is an old saying that you are what you eat.

This is as true of plants as it is of humans. Without

the proper nutrients, plants will not grow and

produce as expected. For plants, proper nutrition

comes from the nutrients in the soil or fromcommercial fertilizer.

Water soluble fertilizers are designed to mix with water and applieddirectly to the plant with a hose or sprayer. This type of fertilizer is ideal for
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foliar feeding but may also be applied to

roots. By applying the mixed fertilizer to

the leaves, plants are able to utilize the

nutrients right away. Nutrients areabsorbed through the leaves and go

directly to plant growth. Run off

penetrates the soil and provides

nutrients that are absorbed by the roots.

Granular fertilizer is applied to the soil and must be mixed into the existingsoil to prevent burning the young roots of growing plants. This formula

breakdowns over a period of time when exposed to rainfall or regular

watering. It may be applied prior to planting and during the growing

season. Contact with leaves will cause plant damage.

Each of these fertilizer types comes in a premixed formula that consists ofthree main elements: nitrogen, phosphorus and potassium, sometimes

referred to as potash. The numbers indicated on the bag, such as 10-10-

10, represent the percentage of each element in the formula. To determinewhich formula is right for you, you need a basic understanding of the

effect each element has on plant growth.

Nitrogen works to promote lush green leavesand rapid growth. When applied at the right

time, nitrogen will give your plants a boost in

growth, but it is best applied early in the

growing season, well before the onset of

blooming and fruit. If too much nitrogen is

applied close to blooming time, you may

sacrifice blooms and end up with lush


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vegetation that fails to set fruit. A lack of nitrogen will result in yellowing

or curling of older leaves and stunted growth.

Phosphorus promotes vigorous blooms and healthy plant cells. Apply afertilizer high in phosphorus just prior to blooming to encourage profuse

blooms that are brimming with color. Plants suffering from a phosphorus

deficiency may show signs of purpling along the veins.

Potassium is needed to build a strong root system to support the plant'sgrowth and to maintain health. This is especially important for large plants

that require vigorous root systems for support. A lack of potassium will

result in stunted growth and general poor health.

ADVANTAGES OF CHEMICAL FERTILISERS1. Chemical fertilizers have smaller bulk and hence

are easy to store, transport and apply.2. Chemical fertilizers are nutrient specific. Thus for

supplying a particular nutrient we can select somespecific chemical fertilizer. For example, super

phosphate is used in case the soil is deficient in

phosphorus.

3. Chemical fertilizers are soluble in water and hence are easily absorbed by

plants.


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NEGATIVE EFFECTS OF CHEMICALS FERTILISERSThe biggest issue facing the use of chemical

fertilizers is groundwater contamination. Nitrogenfertilizers break down into nitrates and travel easily

through the soil. Because it is water-soluble and can

remain in groundwater for decades, the addition of

more nitrogen over the years has an accumulative

effect.

At the University of Wisconsin, Madison, they discovered the effects of chemical

fertilizers are compounded when mixed with a single pesticide. They discovered

altered immune, endocrine and nervous system functions in mice, as well as

influence on children's and fetus's developing neurological, endocrine and

immune systems. These influences "portend change in ability to learn and in

patterns of aggression."

One popular fertilizer, urea, produces ammonia emanation, contributes to acid

rain, groundwater contamination and ozone depletion due to release of nitrousoxide by gentrification process. With it's increased use and projections of future

use, this problem may increase several fold in the coming decades.

Groundwater contamination has been linked to gastric cancer, goiter, birth

malformations, and hypertension; testicular

cancer and stomach cancer.

Excessive air- and water-borne nitrogen fromfertilizers may cause respiratory ailments,

cardiac disease, and several cancers, as well as

can "inhibit crop growth, increase allergenic

pollen production, and potentially affect the


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dynamics of several vector-borne diseases, including West Nile virus, malaria,

and cholera."

Perhaps one of the scariest effects of chemical

fertilizers is something called

methemoglobinemia. In infants it is

alternatively known as Blue Baby Syndrome.

The risk most often occurs when infants are

given formula reconstituted with nitrate

contaminated water. The condition causes a decrease in oxygen in the blood and

results in a blue-grey skin color, causes lethargy and/or irritability and can lead

to coma or death.111 I've been unable to find whether the same risk exists for

breastfeeding babies whose mothers drank contaminated water.

Nitrogen groundwater contamination also contributes to marine "dead zones".

The increase in the water-soluble nitrates creates an influx of plant-life, which

eats up oxygen and starves out fish and crustaceans. This has an impact not only

on the aquatic ecosystem, but on local societies who depend on food sourced from

those areas.

And then there is the highly questionable use of raw sewer sludge as a fertilizer.

Yes, you heard me right. In some countries, raw, uncomforted and untreated

human waste is applied directly to crops and soil, a practice known as "night soil"

since it's typically applied at night. The risk of disease is obvious and highand this

practice should never be confused with "humanure", a long, highly involved

process of decomposing human waste into a safe resource.


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What is organic fertilizer?

There are natural, organic fertilizers that aren't made bymixing chemicals together. Organic fertilizers are made bymixing natural ingredients, ingredients that are naturally

high in N or P or K or all of them, and that also contain

trace elements.

Chicken poor blood and bone meal or fish extract and things like that. They

contain the NPK in varying ratios, and some trace elements, and maybe other

gobbledygook like growth factors, auxins , macromolecules, enzymes.

However, it's still easily possible to get the balance wrong, especially if you don't

know what exactly is in that bag and what exactly your plants need.

Maybe it's theoretically possible to grow reasonably healthy kids on a diet like

that, if you do add enough different herb, fruit and vegetable extracts, in a high

quality form where most of the goodness in them is actually preserved. And if you

really understand what you are doing there, what EXACTLY the kids need!

Harmful Effects of Fertilizers

According to the Environmental Protection

Agency, most fertilizers contain about the

same basic materials: nitrogen, potassium,

phosphorus and sometimes other nutrients,like zinc, needed for healthy plant growth.

Many people use fertilizers to give extra life

to their lawn and garden, but few people

consider the potential drawbacks of these


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fertilizers. In an effort to be as environmentally conscious as possible, it is

important to consider the potentially harmful effects of fertilizers as well as the

benefits.

Human CarcinogensThe most significant harmful effects come from fertilizer that is designed to kill

or prevent weeds. According to the EPA's Office of Pesticide Programs, 12 of the

most popular pesticides in the United States have ingredients known to cause

cancer. Organic fertilizers are guaranteed to be safe for the

environment, the body and free of pesticides.

Water PollutionWhile fertilizers may be beneficial to the plants,

they are not always as healthy for the rest of the

environment. Many of the "quick-release"

fertilizers have been known to lead to oxygen

loss in waterways due to runoff into the street

and, as a result, into the water. High amounts of

nitrogen can find their way into waterways in

this way, causing an excess of algae and a resulting loss of oxygen in the water.

This can have a negative effect on fish and other wildlife in the water.


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Toxic Waste PotentialMany people do not realize that some fertilizers are made from the residuals of

waste water treatment facilities or recycled from other areas that cause them totest positive for toxic waste. According to the federation of Public Interest

Research Groups (PIRG), 29 popular fertilizers tested positive for 22 toxic heavy

metals, including silver, nickel, selenium, thallium and vanadium. All of the

metals found are linked directly to human

health hazards.

Chemical Fertilisers

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