08 October, 2024
Five important facts about fertilisers
In December 1905, Sam Eyde and Kristian Birkeland successfully produced nitrogen fertilizer at Notodden, Norway. This groundbreaking achievement has helped increase agricultural productivity and today, half of the world’s population has food on their table due to fertilizers. Here are five important facts you should know about fertilizers and their importance in safeguarding lives and nourishing our world!
Fact 1: Fertilisers do not deplete the soil
Fertilisers are key to rejuvenating the soil by providing nutrients the plants need to grow healthily.
In nature, there are 17 critical plant nutrients: the macronutrients nitrogen, phosphorus, potassium, calcium, sulphur, magnesium, oxygen, hydrogen, carbon, and the micronutrients iron, boron, chlorine, manganese, zinc, copper, molybdenum and nickel.
When crops are harvested, the nutrients follow the crop. Important nutrients are therefore removed from the soil. Often the soil is not able to replenish all the nutrients by itself, that is where fertilisers are crucial in supplying the nutrients that are lacking. In turn, this maximizes crop yield and quality.
In the US alone, the average corn yields have more than doubled since 1968(1), through more effective farming.
Both organic and mineral fertilisers can be used to replenish the soil. While the nutritional content of organic fertilisers can be inconsistent, influenced by soil health and climate, mineral fertilisers offer high nutrient concentration and immediate availability. However, as mineral and organic fertilisers complement each other, a comprehensive nutrient program should incorporate both.
"Fertilisers are essential for reducing deforestation, rejuvenating soil health, and ensuring sufficient food production for a growing global population."
Fact 2: Fertilisers are made of natural elements
All the nutrients contained in different fertilisers are found in nature.
The most common sources of nutrients in mineral fertilisers are nitrogen, potassium and phosphate. These natural sources are processed industrially and transformed into mineral fertilisers.
Nitrogen makes up 78 percent of the air we breathe, but plants cannot get it directly from the air - they need to take it up through the roots from the soil.
The most common process in nitrogen fertiliser manufacturing is to create ammonia from a mixture of nitrogen from the air and hydrogen from natural gas.
Potassium is sourced from old sea and lake beds formed millions of years ago. Since potassium sources are often located far below the soil surface (1-2km depth), plant roots are unable to reach them naturally.
Potassium fertilizers are based on naturally occurring potassium chloride. This is somewhat similar to table salt – sodium chloride.
The ash from burning wood or straw is high in potassium, this is where the name ‘potash’ originates.
Phosphate is sourced from insoluble calcium phosphate rocks – often referred to as “rock phosphate”. In this form it is not available to plants. Rock phosphate is made available for the plant usually through a chemical process to create plant friendly fertilisers.
Nitrogen (N), phosphate (P), and potassium (K) can also be combined to form NPK compound fertilisers, that provides the crop with the three major nutrients at the same time.
Like mineral fertilisers, organic fertilisers are also made of natural elements - or materials with a biological origin. These include animal wastes, crop residues, compost, biosolids and more.
Fact 3: Fertilisers are not the same as pesticides
"The most prevalent misconception is the belief that mineral fertilisers are pesticides and are considered harmful or poisonous," says Ole-Jacob Siljan, Plant Manager at Yara Porsgrunn, home to the world's largest NPK fertiliser production facility.
Pesticides are synthetic or natural chemicals used to control pests. Pesticide is a commonly used term for all crop protection chemicals, which also include fungicides that control fungal diseasesand herbicides that control weeds.
Fertilisers, on the other hand, supply natural nutrients to make crops grow.
The role of fertilisers is to increase yield and ensure healthy produce by supplying the right balance of nutrients to the soil.
Fact 4: Fertilisers do not alter the plants we eat
Fertilisers do not alter the DNA of crops. Instead, they improve the growth and quality of the crop by adding important nutrients.
The amount of nutrients added is chosen by the farmer after analyzing the soil and determining the requirements of individual crops.
Fertilizing in the correct way can have a great impact on crops' yield, appearance and nutritional value.
Fact 5: Fertilisers do not make you ill
Eating crops from a fertilized field, or meat from animals that have grazed on a fertilized pasture, does not pose any health risks for animals or humans.
On the contrary, the nutrients in the fertilizer required for crop growth, are the same nutrients required for human growth and development.
Fertilisers are critical to the quality and nutritional properties of the food we rely on.
Mineral fertilisers serve as a vital source of nutrients for soils, livestock, and ultimately, human consumers. Without the precise and balanced application of mineral fertilizers to ensure plants receive the necessary nutrients, resulting food may lack the crucial nutrition required for human health and wellbeing.
Ultimately, careful fertilizing can help combat disorders caused by malnutrition. In countries where specific nutrient deficiencies are a problem, fortifying fertilizers with the relevant micronutrients have also helped better the health of large populations.
Zinc and selenium are two examples of minerals that have been successfully applied to fertilisers to combat deficiencies in large populations.
External resource:
1 - Historical Corn Grain Yields for the U.S. (Purdue University website/Corny News Network)
