Important Questions on Fertilizer and the Environment

Important questions on fertilizerand the environment

Qs

A Mineral fertilizers - Essential plant nutrients for sustainable food production

Contents

Do fertilizers increase soil fertility (productivity)?How are fertilizer application rates derived?How much fertilizer does a crop need?What constitutes balanced and timely applications of fertilizers?Does precision farming give any benefit to the farmer or the environment?Is the condition of fertilizer spreaders important?What is the effect of uneven spreading of fertilizers and how can it be minimised?How efficiently is fertilizer nitrogen used by crops?What is the efficiency of different forms of nitrogen in crop production?Do fertilizers acidify the soil?Does fertilizer use make plants susceptible to pests, disease and weed infestation?Do fertilizers cause soil compaction and/or erosion?Does fertilizer use contribute to drought problems in agriculture?

Q1Q2Q3Q4Q5Q6Q7Q8Q9Q10Q11Q12Q13

Yara – the global company

The role of fertilizers in: Feeding the world - the social dimension of sustainability

Making crop production competitive - the economic dimension of sustainability

Protecting the environment - the ecological dimension of sustainability

What is fertilizer?How and when were fertilizers invented?Why are mineral fertilizers necessary?How are fertilizers produced?Where do fertilizer raw materials originate?How long will the natural deposits of raw materials for fertilizers last?Why manufacture soluble mineral fertilizers? Why not just grind up natural minerals?Why are manufactured fertilizers called “mineral fertilizers” and sometimes “chemical fertilizers”?Which nutrients are most needed?Why is adding sulphur to fertilizers more necessary now than previously?Organic fertilizers: Are they environmentally better or worse than mineral fertilizers?Can nature make up for nutrient deficiencies?What happens to nitrogen fertilizer?

Q14Q15Q16Q17Q18Q19Q20Q21Q22Q23Q24Q25Q26

What environmental problems occur if application rates are well below recommended rates?What detrimental effects can excessive nitrogen application cause?Do fertilizers leach to ground water?Isn’t there an increased risk of leaching when applying highly soluble nitrogen fertilizers?Do fertilizers give off ammonia, which is an atmospheric pollutant?What problems does ammonia volatilization cause?Is the economic optimum fertilizing intensity in conflict with environmental consideration?Do we gain or lose useful energy by using mineral fertilizers?How much energy (fossil fuel) does it take to make one kg of nitrogen fertilizer?Are fertilizers free of toxic substances and safe to handle?What is the company’s policy regarding fertilizers and the wider environment?

Introduction

B Fertilizer use in agriculture

C Fertilizer – Environmental impacts

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Yara

Yara - the global company

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Yara is the worlds leading producer and supplier of mineral fertilizers providing farmersand growers with essential plant nutrients required for sustainable crop production.With more than 6,500 employees worldwide, Yara is operating from 50 countries,and with sales to more than 120 countries through an extensive marketing anddistribution network of more than 160 plants, terminals and warehouses, ‘The rightproducts in the right place, at the right time ‘are the keys to success in the internationalfertilizer industry.

Yara is the most international player in this industry.

The company’s core business is the production and marketing of plant nutrients in theform of nitrogen fertilizers and complex NPK compound fertilizers, together with otherproducts to offer customers a balanced nutrient portfolio of mineral fertilizers. Theproduct range includes ‘value added’ speciality fertilizers especially formulated forcash crops like fruit and vegetables where the contribution to quality and nutritionalcontent is equally important to yield. Agronomic competence and support is a uniqueand integral part of Yara’s offer to growers, wherever they are in the world.

Fertilizers play an important role in harvesting energy and capturing CO2. Theystimulate plant growth, and the solar energy stored in the plants may be 5-10 timeshigher than the energy needed to make the fertilizer products. Furthermore, growingplants capture CO2 in their biomass. If this biomass is used as an energy source toreplace fossil fuel, fertilizer can help reduce global climate gas emissions. Optimumfertilizer input gives optimum yields and at the same time produces high amounts ofcrop residues, which contribute to organic matter in soil.

Mineral fertilizers are made from naturally occurring raw materials (nitrogen is extractedfrom the air and combined with natural gas to form ammonia, whilst phosphate andpotash are extracted from mined rock) containing nutrients which are transformed byindustrial processes into forms that are available to plants. Yara is committed to thefurther development of fertilizer products which meet high demands on quality,agronomic efficiency, safety and environmental care. Yara’s operational proceduresand technical standards are continuously reviewed to match best industry practices.

The role of fertilizers is to supplement the natural supplies of nutrients so that thecrop can reach its full growing potential and produce optimum yields. On average, theuse of mineral fertilizers doubles the yield of crops in developed countries and increasesyields by 30 - 40% elsewhere. This brings four main benefits:

It generates food for the non-farming population It makes farming profitable for the farmer It reduces the cost of food production and increases its efficiency It minimises the land area needed for agriculture

In a world characterized by continuous population growth and limited availability ofnew land for farming and cultivation, soil productivity must be continuously increasedin order to satisfy the demand for food. Without the use of mineral fertilizers, a largeproportion of the worlds population would starve. A further benefit is reduced pressureon natural vegetation through increased production from cropped land.

The role of fertilizers

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Between 1950 - 1996 the world population increased from 2,000 million to 6,000million. If growth rates continue there will be 8,000 million by 2020. More than90% of this growth is expected to occur in developing countries.

Crop growth and yield are governed by climatic conditions and the availability of waterand plant nutrients. At harvest, nutrients are removed from the soil by the crop andthey need to be replaced. The nutrients in the soil reserves and from organic manuresare not sufficient, mineral fertilizers provide the additional input required for increasingcrop yields. Yield increase has followed the increase in world population and mustcontinue to do so if hunger is to be avoided.

Mineral fertilizers play a vital role in feeding the world. The rising food demandto feed the expanding population since the 1960’s has been met from increasedfood production largely on existing agricultural land. This was made possiblefrom more use of mineral fertilizers combined with other developments, includingplant breeding, plant protection products, cultivation techniques and use ofirrigation.

Global trends in population growth, grain yield and origin of plant nutrients

Gra

in y

ield

t/h

a

Pop

ulat

ion,

10

00

mill

ion

Year1950 1960 1970 1980 1990 2000 2010 2020

8 -

7 -

6 -

5 -

4 -

3 -

2 -

1 -

0 -

Actual dataProjected

- 4

- 3

- 2

- 1

- 0

Fertilizers

Manure

Soil reserves of nutrients

Population

Grain yield

Source: Stapel (1982) with latest data added.

The role of fertilizers in:

Feeding the world- the social dimension of sustainability

"Because synthetic nitrogen fertilizers provided about half of the nutrient inharvested crops, roughly 40% of the world's dietary protein supply in themid-1990's originated in the Harber-Bosch synthesis of ammonia."

(Abstract: Professor Vaclav Smil, University of Manitoba, Canada. 1999 Travis P Hignett Lecture, IFDC, AL, USA. IFDCReference: LS-2, October 1999.)

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Making crop production competitive- the economic dimension of sustainability

Fertilizers maintain soil fertility and productivity through supplying/replacing essentialplant nutrients and therefore make a vital contribution to economic crop production.Cultivated soils do not usually contain sufficient amounts of plant nutrients for highand sustained crop yields. Harvesting crops removes nutrients and if they are notreplaced (through use of fertilizers) soil mining results, yields will diminish,crops will develop deficiency symptoms and in extreme cases, fail altogether.

The world's population is expanding, thus creating a need for increased food productionat affordable prices. Fertilizer use on an expanding scale is required for enhanced andeconomic agricultural productivity.

Fertilizers are necessary to support affordable and sustainable agriculture. Yarahas a range of fertilizer products to provide those nutrients in short supply. Optimalfertilizer application with the correct balance of nutrients is required to ensurethe economic production of both high yielding and high quality crops.

0 50 100 150 200 250 300

The use of mineral fertilizers pays off

Fertilizer application, kg N/ha

1200 -

1000 -

800 -

600 -

400 -

200 -

100 -

0 -

Source: Yield data: Long term trial (since 1856), Broadbalk, Rothamsted, UK.

The investment in nitrogenfertilizer is highly profitablefor growers

Net return is 7x theinvestment

Wheat yield response (monetary value)to N fertilizer rate

The role of fertilizers

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Transformation of land in the period 900 - 2000

Water

Ice

Other land

Unexploitable forest

Primary forest

Secondary forest

Natural grass

Grass

Crops

1000 million ha

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13 -

12 -

11 -

10 -

9 -

8 -

7 -

6 -

5 -

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3 -

2 -

1 -

0 -900 1700

18501900 2000

1950

World =44.8bha

Land = 13bha(29% ofworld area)

Freshwater= 3%(70% ‘frozen’)


Protecting the environment- the ecological dimension of sustainability

Man has caused major changes to the land on planet earth. Most notably since the1850’s.

The Earth’s land area is 13 thousand million hectares which is 29% of the Earth’ssurface. Currently about 10% of all land is cultivated, with FAO projections suggestingonly small further expansion is possible. The reserves are mainly in Africa and LatinAmerica.

There are serious constraints on the use of the remaining reserves, such as lack ofwater, land quality, sparse population, preservation of forests and other environmentalconcerns.

Sustainable agriculture with more intensive use of the areas already employed forfood production will help to conserve the land reserves.

This can be achieved by improving the soil’s fertility through the judicious, and greater,use of fertilizers.

Mineral fertilizers play a vital role in conserving the land. Reducing the mineralnutrient input could mean that more virgin land would have to be ploughed up.In sustainable agriculture, the need for good quality food at affordable pricesshould be met with minimum adverse effects on the environment. Excessive ratesof fertilizer application are potentially environmentally harmful as well aseconomically wasteful. Applying fertilizer responsibly and according to goodfarming practices can limit the risk of this occurring.

A Mineral fertilizers - Essential plantnutrients for sustainable food production

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Fertilizers are nutrients for plants, regardless of source.

Besides sunlight, carbon dioxide, oxygen and water, thirteen elements are consideredessential for plant growth. These are divided into:

Major nutrients - N, P, K (nitrogen, phosphorus, potassium). Secondary nutrients - Ca, Mg, S (calcium, magnesium, sulphur). Micro nutrients - Fe, Mn, B, Zn, Cu, Mo, Cl (iron, manganese, boron, zinc, copper, molybdenum, chlorine).

Some crops may benefit from other elements, e.g. Na (sodium) for sugar beet andsome tropical crops, and Si (silicon) for maize, grasses and particularly rice.

The primary and secondary nutrients are required in the largest amounts, althoughthere are large variations of requirement between crops. They are the constituentsof many plant components including proteins, nucleic acids and chlorophyll, and areessential for processes such as energy transfer, maintenance of internal pressure andenzyme function. Micronutrients are the ‘vitamins’ of plants. They are not needed inlarge quantities but are necessary for plant health.

The components of mineral fertilizers are normal constituents of the soil in theinorganic form and are environmentally benign. In organic fertilizers the nutrients arepartly tied up in organic compounds that have to be mineralized to be available toplants.

Mineral fertilizers can supply the balance between the amount of nutrientsavailable from other sources like the soil, air or organic manures, and a cropsnutrition requirement.

What is fertilizer?Q1

PN K

Ca Mg S B Zn Fe Cu Mn Mo Cl

Primary nutrients

Secondary nutrients Micro-nutrients

H2O

CO2

O2

Primary, secondary and micro-nutrients

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How and when were fertilizers invented?Q2

JUSTUS VON LIEBIG1803 - 1873

A Deficiency of any SingleNutrient is Enough to Limit Yield

SMg

Ca

K

P

N

plant residues

organicmatter

mineralization

plant residues are decomposed into minerals

manures

fertilizers

How plants take up nutrients

Manufactured fertilizers were introduced to European agriculture in the middleof the 19th century, after the discovery of the principles of plant nutrition.

In the 1830’s, Justus von Liebig (1803-1873) discovered that minerals like nitrogen,phosphorus and potassium were plant nutrients. The scientist concluded that thesemineral plant nutrients originated from mineralized plant residues and other organicsoil material. It was concluded that a deficiency of any single nutrient was enoughto limit yield.

The value of fertilizers was demonstrated in the worlds first agricultural field trialsat Rothamsted in the UK. These trials continue to provide valuable information infertilizer efficiency, with the long term trial on the Broadbalk site in continuous existencesince 1856.

The history of fertilizer manufacture begins around 160 years ago. Some importantmilestones are:

1842 - J B Lawes produces superphosphate from rock phosphate at Rothamsted 1905 - First production of synthetic nitrogen fertilizer at Notodden in Norway 1911 - Haber-Bosch process introduced to manufacture ammonia 1927 - Nitrophosphate process developed in Norway

Yara’s history goes back to 1905 when Norsk Hydro was established followingthe revolutionary invention of Birkeland & Eyde, utilizing Norway’s vast reservesof hydroelectric power to capture nitrogen from the air.

Yara has responded to the global need for mineral fertilizers through developingfertilizer products and expert advice systems and services, which promote theresponsible use of the Company’s products and support sustainable agriculturalproduction systems. Agronomic competence is a unique and integral part of Yara’soffering to growers of crops, wherever they are in the world.

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Sod

ium

Oxy

gen

Bor

on

Car

bon

Dio

xide

Soil Conditions& Other

Growth Factors

Wat

er

Nit

roge

n

Pho

spho

rus

Pot

assi

um

Cal

cium

Mag

nesi

um

Sul

phur

Iron C

hlor

ine

Yield

War

mth

Ligh

t

Yield

soil

The ‘law of the minimum’ illustrated bybarrel staves of varying lengthsrepresenting growth-controlling factors.

Fertilizers maintain soil fertility/productivity through supplying/replacing essentialplant nutrients and therefore make a vital contribution to economic crop production.

Cultivated soils do not usually contain sufficient amounts of plant nutrients for highand sustained crop yields. Harvesting crops removes nutrients and if they are notreplaced (through use of fertilizers) soil mining results, yields will diminish, crops willdevelop deficiency symptoms and in extreme cases, fail altogether.The world's human population is increasing, demanding increased food productionfrom agricultural land, at affordable prices. Fertilizer use on an expanding scale isrequired for enhanced and economic agricultural productivity.

Fertilizers are necessary to support an affordable and sustainable agriculture.Yara has a balanced nutrient range of fertilizer products to provide those nutrientsin short supply. Optimal fertilizer application, with the correct balance of nutrientsis required to ensure the economic production of both high yielding and highquality crops.


Why are mineral fertilizers necessary?Q3

The economic gains from applying mineral fertilizer

Treatment

No fertilizer

Mineral fertilizer192 kg N/ha

2.1 235 593 -358 282

9.3 1042 885** 157 95

* Assuming grain market price: 112 EUR/tonne (EU intervention price = 101 EUR/tonne)** Cost increase due to intensive production including purchase of N fertilizer

Source: Winter wheat, long term trial, Broadbalk, Rothamsted (since 1856).Production cost: data from KTBL Germany.

9 Yara ©

0 50 100 150 200 250 300

The use of mineral fertilizers pays off

Fertilizer application, kg N/ha

1200 -

1000 -

800 -

600 -

400 -

200 -

100 -

0 -

Source: Yield data: Long term trial (since 1856), Broadbalk, Rothamsted, UK.

The investment in nitrogenfertilizer is highly profitablefor growers

Net return is 7x theinvestment

Wheat yield response (monetary value)to N fertilizer rate

The production processes vary in accordance with the nutrients needed to beincluded in the fertilizer.

The components of finished fertilizer products are relatively simple chemicals, buthighly developed manufacturing technologies are employed in the production of highquality mineral fertilizers. There are various steps involved in their manufacture, fromthe raw materials, through intermediates, to the finished products.

Nitrogen (N) Fertilizers:The supply of nitrogen, determines a plant’s growth, vigour, colour and yield. Increasingthe nitrogen supply to a crop tends to increase the crop’s content of substances thatcontain nitrogen such as proteins and vitamin B1.

The intermediate product in the case of nitrogen fertilizers is ammonia (NH3), whichis produced by combining nitrogen extracted from the air with hydrogen which isobtained from natural gas, or through the hydrocarbon steam reforming process.Approximately 85% of the ammonia plants in the EU use natural gas. Measures toimprove production processes have focused on reducing the amount of hydrocarbonfeedstock required to produce a tonne of ammonia.The further processing of ammonia produces straight N fertilizers such as urea,ammonium nitrate and calcium ammonium nitrate, as well as solutions of the abovefertilizers and ammonium sulphate. Ammonia is also the main intermediate for manymulti-nutrient fertilizers.

Phosphate (P) Fertilizers:Phosphorus is required for good rooting and resistance to drought, for plant growthand development, for the ripening of seed and fruit and in the manufacture and useof sugars and complex carbohydrates. A good supply of phosphorus is essential in thefirst stages of a plant’s life and for early maturity.This nutrient is often described or declared as phosphate (P2O5) rather than phosphorus(P). This is just a convention and the terms can be used interchangeably but care needsto be taken with fertilizer recommendations, as 1 kg P is equivalent to 2.291 kg P2O5.

Rock phosphate (27 - 38% P2O5) is the raw material source from which most typesof phosphate fertilizers are produced, with minor exceptions such as basic slag (12 -18% P2O5), which is a by-product of steel production.

In its unprocessed state, rock phosphateis not suitable for direct application, asthe phosphorus it contains is insoluble atsoil pH above 6.5. To transform thephosphorus into a plant-available formand to obtain a more concentratedproduct, phosphate rock is processed usingsulphuric acid, phosphoric acid and/ornitric acid. Acidulation by means ofsulphuric acid produces either phosphoricacid, an intermediate product in theproduction of triple superphosphate (TSP),monoammonium phosphate (MAP),diammonium phosphate (DAP) andcomplex fertilizers, or singlesuperphosphate (SSP). Acidulation usingphosphoric acid produces TSP, andacidulation using nitric acid produces NPslurries for use in the manufacture ofcomplex fertilizers.


How are fertilizers produced?Q4

Ammonia plant

Nitric acid plant

Nitrophosphate plant

Phosphoric acid plant

Sulphuric acid plant

Urea plant

Ammonium nitrate plant

Calcium nitrate plant

NPK fertilizer plant

Ammonium phosphate plant

Natural gasWaterAir

WaterAir

Rock

Rock

Sulphur

CO2

Superphosphate plant

H2PO4H2SO4

HNO3

NH3

Salts of K, Mg, S

Rock

AN

Fertilizer production routes

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Potash (K) Fertilizers:Potassium controls water relations in plants and helps give plant cells their turgor orstiffness. This is important for crop quality and resistance to disease. Sufficientpotassium is also critical for vitamin and mineral content, for texture, firmness andresistance to drought. It is particularly significant in plants that store large amountsof sugar and starch, like potatoes. It is also vital for the root nodule bacteria onlegumes which fix nitrogen from the air.This nutrient is often described or declared as potash (K2O) rather than potassium (K).Whilst just a convention, the terms can be used interchangeably but care needs tobe taken with fertilizer recommendations, as 1 kg K is equivalent to 1.205 kg K2O.

Most potassium used in fertilizer production is taken from natural deposits of potassiumchloride. The mined material is crushed and purified by the removal of rock particlesand salt and then applied direct, or more usually incorporated in NPK fertilizers.Relatively small amounts of potassium sulphate also are used in fertilizers.

Multi-nutrient Fertilizers:Multi-nutrient fertilizers produced in the EU are either complex fertilizers (every particlecontains the same ratio of nutrients), or blends (made by mixing particles of differentmaterials). Typically, complex NPK fertilizers are manufactured by producing slurriesof ammonium phosphates, to which potassium salts are added prior to granulationor prilling. PK fertilizers, on the other hand, are generally produced as compounds bythe steam granulation of super phosphates (SSP or TSP) with potassium salts.

Yara has a balanced nutrient range of fertilizer products, which has been speciallydeveloped for the world’s major crops. The Company produces and marketscomplex NPK’s, Nitrates (ammonium nitrate, calcium ammonium nitrate andcalcium nitrate), UAN, Urea, Ammonia and other differentiated and value addedspeciality fertilizers containing one or more micronutrients.

Yara Glomfjord - Emissions to Air

Every year all Yara sites publish an environmental map with emission figuresand performance relative to the environmental permits.

11 Yara ©

Nitric acid plants A and BNitric oxides (NOx): 0.28 tonne/dNitric Acid Plant A Nitric oxides (NOx): 0.15 tonne/dNitric Acid Plant B Nitric oxides (NOx): 0.13 tonne/d

Complex fertilizer plantNitrogen (N) 4.4 kg/hFluorides (F) 0.04 kg/hAmmonia (NH3) 16.2 kg/hSulphur dioxide (SO2) 0.14 kg/hFertilizer dust 21.4 kg/h

To water:Nitrogen (N) 1.88 t N/dPhosphorus (P) 0.13 t P/d


Where do fertilizer raw materialsoriginate?Q5Most are from natural sources like the air, and minerals mined from the earth.

The principal raw materials for fertilizer production are:

Air to provide nitrogen. Natural gas and oil to provide hydrogen and energy (for production of ammonia). Rock phosphate (natural minerals with largest known reserves in North Africa, South Africa, USA, China). Potassium salts (natural minerals with largest reserves in Canada, Russia, Belarus, Germany). Sulphur (for production of sulphuric acid used in the production of most phosphate fertilizers (mainly from desulphurization/cleaning of oil and gas).

Extraction and processing of any raw materials can have environmental effects andproduction plants must comply with local regulations.

Mining of phosphate and potash minerals can cause landscape changes. Phosphaterock mines are often operated as opencast sites, with large amounts of waste rockgenerated and considerable landscape restoration is required to minimize the impact.

Some phosphate rock contains minor amounts of naturally occurring radioactiveelements, e.g. uranium. Special precautions may be necessary to provide safe storagefor mining wastes. Uranium has occasionally been a commercial by-product ofphosphate mining.

Potassium extraction can give brines as a by-product, which could cause pollution towater.

Sulphur is extracted from stack gases e.g. electric power plants burning fossil fuels.Much of this sulphur is utilized by the fertilizer industry. This helps to reduceenvironmental pollution from sulphur dioxide in gas emissions from industry.

Yara has participated in the development of the EuropeanFertilizer Manufacturers Association’s (EFMA) ProductStewardship Programme to ensure that proper care istaken along the whole chain-from product developmentand purchase of raw materials, during production andstorage and in the distribution network. The Companyhas adopted and expanded on the requirements in itsown application of the principles, and works accordingto the highest standards, complying with legislationwith regard to health, occupational and public safety,environment and security. Best available technologiesare adopted.

Product Stewardship (from mine to farm)

Application &Farmer services

ProductStewardship

Marketing& Sales

Storage

Transportation Manufacturing

Sourcing ofmaterials

Packaging

Productdevelopment

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Phosphorus and potassium are considered to be among the most abundant elementsin the earth's crust. Scarcity of fossil fuels as a raw material and for energy usein production is of concern.

Agriculture is a relatively minor user of energy, using less than 5% of total EU energy,with food processing, transport and preparation accounting for a further 10%.

There are known reserves of oil and natural gas for approximately 40 to 60 years.New deposits are found each year, but at some time in the future, scarcity may appear.When this happens other methods for fertilizer production will be needed, for examplethat based on hydro electric power discovered by Norsk Hydro in 1905.

Lifestyles in the developed world and rising demand from growing economies in China,South America and elsewhere, will affect the future price, and perhaps supply, of oiland gas. This will directly affect production of nitrogen fertilizers.

Phosphorus and potassium are considered to be among the most abundant elementsin the earth's crust. Easily available resources of phosphate are expected to last forabout 90 years, and it is likely with ongoing exploration activities, that more will bediscovered.The same is true for potassium reserves.

Raw materials for other plant nutrients are also available in sufficient amounts comparedwith agricultural needs. Boron is a possible exception.

Yara develops and manages the Company’s activities to make efficient use ofenergy and raw materials. It works systematically to reduce emissions to air,water and the ground and to minimize waste and ensure the safe handling of theCompany’s products.

How long will the natural deposits ofraw materials for fertilizers last?Q6

Industry, traffic, households, public services 85%

Food industry 10%

Agriculture production (inclusive mineral fertilizer production) 5%

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European energy use

Why manufacture soluble mineralfertilizers?Why not just grind up natural minerals?Q7Manufacturing processes are necessary for the nutrients in fertilizers to be in aform which is readily available to plants in the quantities required.

Nitrogen:The only naturally occurring source that contains nitrogen in a plant-available formis "Chile saltpeter" (sodium nitrate). This "mineral" in a purified form is used as fertilizer,but supplies are inadequate for world agriculture.

Phosphorus:Nutrients are only available to plants when dissolved in water. Most minerals containingphosphorus are so insoluble that they are ineffective as a phosphorus source thoughsome rock phosphates are sufficiently reactive for use on acidic soils. Even reactivephosphates are too insoluble where a rapid response (on soils with low phosphorusstatus) is needed. Fine grinding of these rock phosphates does not sufficiently improvetheir availability.

Potassium:Most potassium fertilizers contain a ground-up natural mineral, potassium chloride.With a few exceptions, other minerals containing potassium are so insoluble that theyare relatively ineffective as a nutrient source. Very high application rates would berequired, but even then the results would be unreliable.

Production processes developed and used by Yara ensure nutrients are convertedinto forms that can be taken up by plants.

Yara is a truly global fertilizer company with a presence in approximately 50countries around the world, and selling to more than 120 countries through anextensive marketing and distribution network consisting of more than 160 plants,terminals and warehouses.


Plants need three main nutrients:Nitrogen, Phosphorus and Potassium

YIELD ANDQUALITY

YIELD ANDQUALITY

Nitrogen, the main driver of yield

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Major Plants

Office

No. of plants/terminals/warehouses

“On the ground” in 50 countries, sales to more than120 countries, more than 160 infrastructure points.

Yara International -unique global presence and infrastructure

© Yara 14

Why are manufactured fertilizers called“mineral fertilizers” and sometimes“chemical fertilizers”?Q8


Mineral fertilizers is the best descriptive name, as they are manufactured fromminerals.

Mineral fertilizers contain plant nutrients that occur naturally in the soil, in a concentratedform. For more detailed information, please refer to the answers to previous Questions,1-7. Fertilizers that are manufactured are sometimes called ‘mineral’, ‘artificial’,‘inorganic’, ‘industrial’ or ‘chemical’. Of these, ‘mineral’ is the best description as thisdescribes the source. The other terms can be applied to a wide range of material,for example, all nutrients, regardless of source, are inorganic when taken up by plants.Sludge and often organic waste used as fertilizer can be called ‘artificial’, ‘industrial’or ‘chemical.

Yara produces mineral fertilizers to high quality standards, which means:

Nutrients are available to crops. Fertilizer can be spread evenly and accurately. Production processes minimise energy use and emissions.

Nitrogen content in 1 tonne of fertilizer

kg/T

400 -

300 -

200 -

100 -

0 -Cattle

manure

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Mineralfertilizer (AN)

350

5

Fertilizer requirement to apply 100 kgof nitrogen per ha

T/h

a

24 -

18 -

12 -

6 -

0 -Cattle

manureMineral

fertilizer (AN)

0.286

20

Which nutrients are most needed?Q9


Nitrogen, followed by phosphorus and potash.

Generally, the limiting nutrient is the most needed one because it limits the uptakeof other nutrients and directly or indirectly, crop yield.The industrial production of mineral fertilizers makes it possible to correct for thesedeficiencies, and thus maintain soil fertility through balanced fertilization.

On a global scale, nitrogen is the most needed nutrient followed by phosphorus andpotassium. Owing to previous imbalanced fertilization with focus on nitrogen needs,deficiencies in phosphate and potash still occur in some parts of the world, e.g. partsof Asia. Phosphate and potash deficiencies also frequently develop in systems thathave been under organic farming for some years.Sulphur and zinc deficiencies are also quite common worldwide.

Yara has a balanced nutrient range of fertilizer products, which has been speciallydeveloped for the major crops in the world.The Company is the most diversified nitrogen fertilizer company in the world,producing and marketing complex NPK’s, Nitrates (ammonium nitrate, calciumammonium nitrate and calcium nitrate), UAN, urea, ammonia and otherdifferentiated products with additional plant nutrients.

Slowlydegradable

organic P

Easilydegradableorganic P

Fast

Phosphorus in the soil

Non-labile Pin apatites andsoil minerals

Fertilizer P

Soil solutionSlow

Slow

Labile P bondsto minerals

Plant residues,manures

Mineralizationsoil microbes

Nitrogen, the most important nutrient

© Yara 16

Source: IFA statistics season 2003/2004.

Potassium (K)

Phosphorus (P)

Nitrogen (N)

Total 145.6 millionnutrient tonnes production

17%

24%

59%

Why is adding sulphur to fertilizers morenecessary now than previously?Q10


There are various reasons:

Phosphate fertilizers are now more concentrated and thus their sulphur contenthas been reduced.

Rain used to provide enough sulphur to prevent sulphur deficiencies in WesternEuropean crops but the significant reduction in industrial sulphur dioxideemissions has decreased the rate of sulphur deposition from rain.

Sulphur deficiency may have gone unnoticed or been confused with nitrogendeficiency.

Sulphur demanding crops e.g. oilseed rape, are now more commonly grown.

Yields are higher than previously, hence more nutrients, including sulphur, areremoved from the system.

Sulphur deficiencies are now causing yield reductions in some regions and in somecrops, necessitating sulphur to be included in fertilizers.

There are four main sources of sulphur for crops:

The soil organic matter.The air.Organic manures.Mineral fertilizers.

Mineral fertilizers can effectively be applied to balance any deficiency from othersources to meet crop need.

Yara has carried out extensive field trials investigating the response to appliedsulphur on a wide range of crops, soil types and climatic conditions. The Company’sfertilizer recommendation systems take account of all sources of sulphur, andformulations increasingly contain this element to meet the rising crop requirements.

Without and with sulphur.

Oilseed Rape often responds to sulphur.

17 Yara ©

Organic fertilizers:Are they environmentally better or worsethan mineral fertilizers?Q11


Both organic and mineral fertilizers have their place in sustainable agriculture.

Manures and crop residues are by-products in agriculture that contain valuable cropnutrients and should be used wherever available and taken into account when makingfertilizer recommendations.

There are not enough nutrients in organic wastes to compensate for those removedby high yielding crops and for unavoidable losses, the balance must be made up frommineral fertilizers.

There are considerable environmental problems with the use of manures. Techniquesfor improved handling and soil application are being developed.Part of the nitrogen in manures is not available to the crop during the growing season,with some mineralized later during non-vegetative periods, then lost through leaching.Ammonia loss during open storage or after surface spreading of manures can besubstantial.

The separation of livestock and arable farming, with the concentration of animals insome regions and arable crops in others, has lead to nutrient distribution inefficiency,with a surplus in the animal farming regions. The low nutrient content and bulky natureof manures makes transportation inconvenient and costly.

Manures table

Source % dry matter Nutrients, % of dry matter

Cattle manuresSlurryFYMSewage sludgeChemical treatment (Fe/Al)Biological treatmentTown refuseCompost

Source: NMI (cattle manure), ifa/fao conf march 2003 (sewage sludge and town refuse).

922

20 - 4017 - 20

70

4.62.6

0.5 - 30.8 - 5

1.17

P KN

0.80.8

0.2 - 30.1 - 1

0.25

4.81.3

<0.10.1

0.76

Fertilizer characteristics;Organic compared to mineral fertilizer

Characteristic Organic fertilizer Mineral fertilizer

Nutrient source

Nutrient concentration

Nutrient availability

Quality control

Crop residues and animal manures

Low concentration

Variable

Often inconsistent

Nitrogen from the air and minerals from the soil

High concentration

Immediately available for the crop

Traceable and consistent

© Yara 18

Origin and quantity of ammoniaemissions to air in Western Europe

Animal husbandryManure spreading 32%Grazing 8%Manure storage 34%

Mineral fertilizerApplication 12.5%Production 0.5%Leaf emissionfrom crop 5%

Miscellaneous 8%

Source: ECETOC Technical Report No. 62Ammonia Emissions to Air in Western Europe.


Can nature make up for nutrientdeficiencies?Q12Not in current intensive agriculture.

If a deficiency problem has occurred, the relevant nutrient or nutrients must be suppliedfor crops to thrive.

Deficiencies of nutrients indicate that the weathering of soil minerals or the releaseof nutrients from organic matter is too slow to sustain a high-yielding crop. In lowproductive shifting agriculture, minerals are made available to subsequent cropsthrough burning and weathering of soil minerals during a previous break from cropping.

Where soil or crop analysis shows deficiencies, mineral fertilizers fortified with oneor several of the nutrient elements listed in Question 1 can be applied to address thesymptoms and correct the deficiency.

Yara has over many years established an extensive and active presence in worldagriculture. Communication and practical interpretation of the results of theCompany’s extensive Research & Development Programme has been a key aim,and has resulted in the production of advisory tools and expert programs whichgive fertilizer recommendations for most crops, and special tools for nitrogenrecommendations. The ‘Plant Master’ series of brochures cover the major growingaspects of the important crops in the world, and are a key part of communicationwith farmers and growers.

Mg shortage (right).Photo: D. D. Warncke, APS Press.

Lack of one or more nutrients reduce yield and quality

P shortage (left).Photo: P Seward, Yara.

K shortage (right).Photo: Kali and Salz, Germany.

S shortage (right).Photo: Rothamsted exp. station.

Sewage sludge - sometimes called bio solids - is available for application to land buthas a low and varying nutrient content, and it may contain undesirable components(e.g. heavy metals). The phosphorous availability from chemically treated sludge islow, hence processes are under development to recover the phosphorous and makeit more plant available. The use of sewage sludge requires careful consideration ofthe quality and the variability of the product. Some countries, e.g. Switzerland, havebanned the spreading of sewage sludge on agricultural land. Others like Germany arecurrently developing strong quality regulations for unwanted components. Some cropprotocols like EUREPGAP do not allow the application of bio solid products.

Yara fertilizer recommendation programmes routinely take account of, and giveguidance on how to combine mineral fertilizers with organic manures for balancedplant nutrition.

19 Yara ©

So long as it is applied to meet crop requirement and in accordance with goodfarming practice, with locally derived rates and timing, it will be largely takenup by the plant. It is then present in agricultural outputs, grains, fruit, vegetables,milk, meat, and eggs.

The soil nitrogen cycle explains the nitrogen pathways.Nitrogen fertilizers dissolve in soil water and release ammonium-N and nitrate –N,both of which are taken up by crops.

Of the fertilizer nitrogen applied:

Much is taken up by the plant.Some is used by soil microbes and incorporated in the soil’s pool of organic matter(called microbial nitrogen immobilization).The remainder is at risk of loss through leaching and gaseous products (ammonia,nitrogen oxides and di-nitrogen) The amounts are variable depending on the quantity,time and type of nitrogen fertilizer applied, as well as the environmental conditionsof soil and climate.

Yara has an extensive R & D programme to improve fertilizer N use and tominimise risks of nutrient loss from the soil.

What happens to nitrogen fertilizer?Q13


The soil nitrogen cycle

Nitrogen in air (N2)

Nitrous oxide(N2O)

Soluble nitrogen

Insoluble nitrogen

Agricultural output: grain,roots, vegetables,fruits

Ammoniavolatilization

NitrogenFertilizer

milk, meat, eggs, etc.

Manure

Insoluble nitrogen,mainly in organic

matter.

Nitrateleaching

Denitri-fication

Soluble nitrogen:nitrate (NO3-)

ammonium (NH4+)

Nitrogenfixation

© Yara 20


© Yara 21


Do fertilizers increase soil fertility(productivity)?Q14Yes. Crops are mining the soil for nutrients; fertilizers replace those nutrientsand can maintain or increase soil fertility through plant residues building organicmatter in the soil.

Appropriate use of fertilizer contributes to good agricultural practice. Mineral fertilizerapplications can increase soil organic matter through higher levels of root mass andcrop residues.

However, incorrect agricultural practices may diminish soil fertility even where fertilizersare used:

Increased yields increase nutrient removal, and those nutrients must be replaced.If nitrogen only is supplied, the soil can be so depleted of other nutrients thatfertility and productivity suffers.Poor rotations, with little or no return of crop residues or manures can result inreduced soil organic matter content and soil fertility. Fertilizers do not cause suchchanges, but can mask soil deterioration for some time.Repeated use of acidifying fertilizers i.e. ammonium sulphate, can cause increasedsoil acidification if not corrected by lime. Crops have varying tolerances to the pHstatus of soils.

SOILQUALITY

SOILQUALITY

Positive effects on soil quality

Increase or maintain organic matter:mineral fertilizers - increased yieldsorganic manures - organic contentcrop residues left in the fieldcrop rotations including grassconservation tillage

Stabilises aggregates:liming

22 Yara ©

The MCL3 soil sampler. Capable of penetrating the hardestsoil, its cylindric probe technology provides samples down to adepth of 120cm.

By taking all the factors involved in the nutrient status of the site, and requirementof the crop, into account fertilizer rates can be calculated to balance the nutrientsupply to produce optimum yield.

Fertilizer recommendations should meet the crop's demand fornutrients, which is dependent on:

Crop type, variety, quality and end use requirements.Nutrient supply from non fertilizer sources i.e. the soil, organicmanures etc.Previous fertilizer applications and cropping.Local climatic conditions.

Fertilizer recommendations can be estimated from:

Local fertilizer experiments.Farmers’ experience.Soil and plant nutrient analysis.Research based expert programs.

Such information is combined to give estimates of the amounts of nutrients thatshould be applied to obtain the best economic result.There is always difficulty in estimating accurate optimum fertilizer rates because:

The amount of nutrient available from the soil is difficult to establish accurately.The weather represents an unpredictable influence on the crop's need for nutrients.

Yara has developed advisory tools and expert programs, which give fertilizerrecommendations for most crops, and special tools for nitrogen fertilization (N-Tester and N-Sensor), which measure the nutrient demand directly from the plant.Fertilizer recommendations, tools and programmes are essential to increase theaccuracy of managing the nutrient supply to crops. The ‘Plant Master’ series ofbrochures cover the major growing aspects of the world’s most important crops.

How are fertilizer application ratesderived?Q15

Feb

kg N

/ha

Mar Apr May Jun Jul Aug

N demandof the crop

N fertilizerdemand

N supplyfrom the soil

The Yara N-Sensor.


The Yara N-Tester.

© Yara 23

Average nutrient content of various crops

Nutrient

Primary

Nitrogen

Phosphorus (P)

Potassium (K)

Secondary

Sulphur

Magnesium

Calcium

Nutrient removal (kg t-1 of produce as harvested)

Wheat

Grain

21

3.6

3

Grain

1.6

1.2

0.4

Rough rice, Philippines

Grain

14.6

2.6

3

Grain

0.6

1.0

0.1

Straw

9

0.6

28

Straw

0.4

1.6

3.2

Total

23.6

3.2

31

Total

1.0

2.6

3.3

Sugar beet, UK

Root

1.4

0.4

2.7

Root

0.3

0.3

0.6

Top

3.6

0.4

3.4

Top

0.65

0.4

1.2

Total

5

0.8

6.1

Total

0.9

0.7

1.8

Potato

Tubers

4

0.7

5

Tubers

0.4

0.4

0.1

How much fertilizer does a crop need?Q16

(Items written in italics are commercial produce).


It depends on the crop in question, its management, place in the rotation and theexpected yield. The N-Sensor is able to detect areas of different nitrogen supplywithin one field and converts this information into a nitrogen application mapthat takes into account the different nitrogen demands of the crop.

More fertilizer is needed if crop residues are removed, than if they remain in the fieldand are available to the following crop. For example, rice and wheat crops yielding2-8 t grain/ha absorb 50-190 kg N/ha, 6-22 kg P/ha and 65-250 kg K/ha. Thecontent in the grain amounts to 30-120 kg N, 4-16 kg P and 6-24 kg K per hectare,hence, the total amount needed for each crop depends on whether the residues fromthe previous crop are left in the field.

Crops such as sugar beet and potatoes have a largerproportion of the nutrients in the crop residues, thus,their fate is important when considering the nutrientneeds for the following crops and should be taken intoaccount when fertilizer plans are made.

Yara fertilizer recommendation programs takeprevious cropping into account, as well as the otherrelevant site-specific factors e.g. variety, soil type,planting date etc. Fertilizer recommendations toolsand programs are essential for increasing theaccuracy of management of the nutrient supply tocrops and for providing a record, required by manycrop growing protocols. The Yara ‘Plant Master’series of brochures has been produced for mostmajor crops.

Sensor map:Without slurryCattle slurryPig slurry

N-Application map

Spectralindex

High

Low

N (kg N/ha)

100

90

80

70

60

50

40

Winter Barley. N-Sensor measurement and N-application on the 25th of May 1999.Source: AgriCon, Germany.

24 Yara ©

Average nutrient content of various crops


What constitutes balanced and timelyapplications of fertilizers?Q17Balanced fertilizer use implies that:

The different nutrients are supplied in the right proportions according to theplant's needs.

All nutrient sources available to the crop are taken into account, i.e. mineralfertilizers, farmyard manure, sewage sludge, crop residues etc.

The total supply of added nutrients from all sources is just sufficient to meetthe crops requirement, so that deficiencies are avoided and nutrient residuesin the soil after harvest are minimized.

Unbalanced fertilizer use, for example only applying nitrogen, can give yields belowthe optimum, increase the crop's susceptibility to insect and fungal damage, andreduce crop quality.Timely fertilizer use means to apply fertilizer at or just prior to the time the croprequires a rapid uptake of nutrients. This also minimises any environmental impactof fertilizers.Plant analysis can be used to determine the nutrient status of the crops and the righttiming of fertilizer application.Fertilizers should not be applied outside and towards the end of the growing season,or when heavy rain is expected.

Yara provides a wide range of fertilizer grades that enable the farmers to selectthe right balance of nutrients for their crops. Yara has developed advisory toolsand programs which give fertilizer recommendations and timing of applicationsfor most crops, with more specific tools for nitrogen recommendations.

© Yara 25

Does precision farming give any benefitto the farmer or the environment?Q18


Yes, it benefits both.

Precision farming technology helps the farmer to apply the optimum amount offertilizer on each spot within a field. The accurate application of fertilizer accordingto the actual nutrient demand of the crop avoids over-fertilization as well as under-fertilization in a field. This variable rate fertilizer application results in higher yieldsand reduced losses to the environment as the applied fertilizer is utilized more efficientlycompared to a standard fertilizer application, which is uniform for the whole field.Standard application doesn't take into account the varying nutrient demand within thefield.

Yara has developed N-Sensor, a system for measuring crop nitrogen status as itvaries within a field and for adjusting fertilizer applications accordingly. Currently,the system has been developed for use with winter cereals, oilseed rape, maizeand potatoes.

Is the condition of fertilizer spreadersimportant?Q19Yes, because a poor spreader will not accurately spread fertilizer.

Spreader manufacturers have developed application machinery which can achievegood levels of spreading accuracy in field conditions so long as:

The machine is set up and adjusted for the type of fertilizer to be applied.The operator is proficient.The fertilizer quality (physical properties) is good and the product is free flowingto enable the machine to work efficiently.

Fertilizer spreaders must be well maintained and calibrated regularly by a trainedmechanic.

Yara’s fertilizers have been developed to have consistently good spreadingcharacteristics of size, bulk density and hardness. The Company has a goodrelationship with the worlds leading manufacturers of fertilizer spreaders, andproduct is supplied to them, so that good spreading advice and guidance isavailable for farmers and growers.

26 Yara ©

Uneven spreading is costly to the farmer and is potentially harmful to theenvironment. It can be minimised by choosing a high quality fertilizer with goodspreading characteristics and using a well-maintained spreader to apply thefertilizer.

Costly to the farmer because only the areas receiving the optimum rate will give a fulleconomic return:

The areas ‘over fertilized ‘are unlikely to produce enough extra yield to cover thecost of the additional fertilizer.The areas ‘under fertilized’ are unlikely to have reached their yield potential.

Harmful to the environment because parts of the field could receive excessive rateswhich depending on field conditions and soil type, could be at risk of leaching. Alsoharmful if uneven spreading means fertilizer enters a watercourse.

Evenness of spreading is measured by the coefficient of variation (CV%):

1-15% is considered acceptable in field conditions

Uneven spreading can lead to a loss of yield as shown on this graph:

If you can see striping,loss in yield could becosting:

11.0 euros/ha in winter wheat. 6.5 euros/ha in silage. 7.0 euros/ha in oilseed rape.

Further financial losses can occur if uneven spreading leads to a

loss of crop quality premium. For example, the loss of milling premium in winterwheat could be worth 187 euros/ha (calculated from 22 euros/tonne for an 8.5t/hacrop)

‘Good quality’ describes fertilizers whichare free flowing, and size- matched, togive an even distribution from the spreader.A pneumatic spreader may have moretolerance than a spinning disc machinebut neither type of spreader is able tosignificantly improve the spreadingperformance of a poor quality fertilizer.

Yara’s fertilizers have been developedto have consistently good spreadingcharacteristics of size, bulk density andhardness. Investment in understandingfinancial implications of poor spreadingof fertilizers has been committed viathe Company’s Research & DevelopmentProgramme.


What is the effect of uneven spreadingof fertilizers and how can it beminimised?Q20

Financial losses due to uneven spreading

0 10 20 30 40

50 -

40 -

30 -

20 -

10 -

0 -

WheatOSR

1st Cut

Coefficient of variation (CV%)

The spreading performance of a range of fertilizer products

EXTRAN

Prilled Urea

Yara Size-MatchedGranules

Non-size MatchedPrilled AN + Granules

Non-Size MatchedPrilled Urea + Granules

Coefficient of Variation (CV%)

Products

403010 20

Faintstriping

Clearstriping Spinning Disc

Pneumatic

Acceptable infield conditions

Very inaccuratespread pattern

Poor spreadpattern

Source: Yara R&D programme.Trials carried out by Silsoe Research Institute 1999.Spinning disc and pneumatic machines tested at 24 metres bout width in field conditions (max wind speed 10kmh-1).

Uneven 1st N application with urea inearly spring (spreading width 36m)

Biomass index

low high

Biomass monitoring in May shows a clear stripedpattern with under-fertilized and over-fertilizedstripes in the field. The stripe pattern is due tobad spreadability of low density urea at 36mworking width. Low biomass is a good indicatorof a potential loss of yield.

© Yara 27


Nitrogen efficiency in arable crop production is high.

Experiments with labelled nitrogen in fertilizers applied to cereals show that commonly40 to 70% of the applied nitrogen is found in the crop.

Much of the remainder stays in the soil organic matter. On average 10 to 20% is notaccounted for. This amount is probably lost as leached nitrate (NO3-) or as gaseousemissions (nitrous oxide (N2O), nitrogen oxide (NO), nitrogen (N2) and ammonia (NH3).

The efficiency varies with crop, soil, climatic conditions, type of fertilizer used andthe application method. Urea applied on the soil surface can lose up to 50% of thenitrogen by volatilization as ammonia. Excessive applications increase nitrogen lossesand reduce the nitrogen efficiency.

How efficiently is fertilizer nitrogen usedby crops?Q21

28 Yara ©


Nitrate fertilizers have generally been found to be the most efficient nitrogenfertilizers. Crops use nitrogen mainly in the nitrate form, but can to a lesserextent also take up the ammonium form.Organic nitrogen, urea and ammonium nitrogen are transformed to nitrate in daysor, at most, a few weeks by microbes in the soil.

Main reasons for the higher efficiency of nitrates are:

A quicker availability (ammonium is adsorbed onto soil minerals).No volatilization losses to the air.A lower uptake by soil microorganisms (ammonium is preferred).

The losses of nitrogen by volatilization after application of urea are in the range from0 to 50%, but difficult to predict. Ammonia tends to be lost from calcareous soil,especially where it is low in organic matter, warm and dry. Smaller losses can occurunder these circumstances where UAN (mixture of urea and ammonium nitrate insolution) is applied and even smaller losses where CAN or ammonium nitrate isapplied. The reduction in crop yield due to these losses is almost always less than10% and usually less than 2%. However, a 2% yield penalty is very significant to afarmer and it will always be best practice to use the more effective nitrogen sourcefor local circumstances. Some farmers tend to apply more than the recommendedrate of urea-based fertilizers as an insurance against poor efficiency. Nitrate basedfertilizers are more accurate, no extra nitrogen is required hence losses are minimized.

Nitrate leaching may occur when nitrogen is applied at low crop N-uptake, e.g. duringautumn and winter. In general, split N application with N rates adjusted to the cropdemand effectively minimises the risk of nitrate leaching.

For high N-input systems it might be difficult to find substantial yield differencesbetween ammonium nitrate / calcium ammonium nitrate and urea, but it is importantto note that even a 2.5% loss in yield can significantly reduce the farmer's profitability.

Yara is the most experienced nitrogenfertilizer company globally. TheCompany has carried out many fertilizerfield trials throughout the world tocompare the efficiency of differentfertilizer nitrogen sources. Although thetrial results are very variable with alarge seasonal effect, in most cases,the nitrate-based fertilizers have beenfound to be generally more efficient andalso more reliable compared to urea orammonium-based fertilizers.

What is the efficiency of different formsof nitrogen in crop production?Q22

Hydrolysis

Conversion of urea to nitrate

Nitrification

UreaCO(NH2)2

NitrateNO3-

NitrateNO2-

AmmoniumNH4+

* In soils of pH <7, nitrate usually does not appear as an intermediate product.

© Yara 29


Do fertilizers acidify the soil?Q23Some do, some don't. Soils tend to acidify naturally but the rate of acidificationcan be affected by fertilizer use.

Fertilizers containing ammonium (NH4+) are usually acidifying. Hydrogen ions are

released and so acidity is increased when ammonium N is oxidized by soil micro-organisms to nitrate N. Also, ammonium can displace the basic cations calcium(Ca2+) and magnesium (Mg2+) from the soil which decreases pH. Ammonium sulphateis especially acidifying as all the nitrogen is in the ammonium form and the sulphatecan contribute to acidity. (Fertilizer use enhances crop growth, which, in itself, isacidifying.) In contrast calcium nitrate has a liming effect.

It is important to know the lime status of the soil and its pH status should be checkedat regular intervals. If the soil is prone to acidification lime should be applied asappropriate for the crop, soil and region.

Soil acidification from ammonium

The amount of lime as calcium oxide (CaO) required to neutralize the acidgenerated from the application of 100 kg N with the fertilizer specified.

Lime demand in kg CaO per 100 kg N/applied on arable soil

100 kg CN-N per ha is equivalent to an application of >80 kg CaO

Ammonium sulphate Urea CAN CN

Nitrate nutrition Ammonium nutrition

4.5

5.5

6.0

6.5

4.5

5.5

6.0

6.5

Plant root

NO3-N maintains/increasespH of the rhizosphere

NH4-N acidifiesthe rhizosphere

pH pH

30 Yara ©

>300 kg>100 kg > 48 kg >-80 kg


Does fertilizer make plants susceptibleto pests, disease and weed infestation?Q24Fertilizers promote rapid growth, which is likely to give the crop a competitiveadvantage over some, but not all weeds. Rapid and lush growth can createsheltered and humid conditions within the crop, which could encourage somepests and diseases.

Healthy plants require an ample and balanced supply of nutrients to ward off andrepair attacks by insects and fungi. Appropriate supplies of potassium, calcium andmicronutrients are especially important for crop resistance to disease, while excessivenitrogen application can increase weed growth, diseases and pests.

To avoid such problems:Correctly timed and balanced fertilizer rates should be applied according torecommendations based on plant and soil analyses.The development of nutrient deficiencies should be avoided.

© Yara 31


Do fertilizers cause soil compaction and/orerosion?Q25

Lack of crop cover increases risk of soil erosion.

Not directly.

Soil compaction can be caused by heavy machinery used for soil preparation, seeding,weed control, pesticide application, and harvesting or fertilizer application. Fertilizersas such do not cause soil compaction. Calcium, which is the main component in limeand some fertilizers, enhances the formation of soil aggregates and counteractscompaction.

Soil erosion is mainly due to poor, short-term management practices e.g. ploughingof slopes and crop rotations that do not provide crop cover. Fertilizer use encouragesan abundant supply of roots and plant residues that build up the organic matter in thesoil to reduce the wind and rain erosion problem and aid the establishment of newvegetation on reclaimed land.

32 Yara ©


Does fertilizer use contribute to droughtproblems in agriculture?Q26No. Fertilizer use contributes to more efficient use of the water available to thecrops.

It takes less water to produce one tonne of grain in high yielding agriculture than inmore extensive systems. A finite water supply would therefore be utilized best if thecrop were fertilized to the economic optimum, well protected against pests anddiseases and the appropriate variety is grown.

© Yara 33

Source: Singh, 1994; Carvalho and Bash (1996)

The relation bewteen crop use of water and nutrients

In rainfed, dryland areas, moisture often is the most limiting factor for cropyield, and it is a major challenge to adjust nutrient applications to themoisture regime. Application rates are usually low; however, experienceindicates that judicious fertilizer use is one of the most important factorsin increasing and stabilizing yields of dryland crops. A fertilized crop yields100-150% more than an unfertilized crop, but requires only 20-25%additional moisture. Hence the rate of fertilizer application should bedecided on the basis of the water-storage capacity of the soil and the typeof crop to be grown.

C Fertilizer - Environmental impacts

© Yara 34

C

What environmental problems occurif application rates are well belowrecommended rates?Q27

Fertilizer - Environmental impacts

withfertilizer

andcompost

withoutfertilizer

What detrimental effects can excessivenitrogen application cause?Q28

Human activity has doubled the amounton N in the environment

LegumesMineral fertilizer

withfertilizer

andcompost

withoutfertilizer

Constant cropping without replacing the removed nutrients reduces soil fertilityand can lead to soil erosion problems.

This situation is more likely to arise in less developed countries e.g. Africa. However,prolonged periods of nutrient removal in excess of input may severely reduce soilfertility and productivity in any farming system. Further, insufficient nutrient supplymay lead to a less dense plant cover, which increases the risk of soil erosion. Heavyerosion can remove fertile soil. Permanent plant cover is necessary on steeply slopingland to protect against erosion.

Land use is another environmental impact, which is often neglected. Ifapplication rates are below recommended rates, yields usually decrease.This means an inefficient use of land, which has to be considered as ascarce resource. To produce the same amount of food, more land has tobe cultivated.

Yara has developed advisory tools and expert programs which givefertilizer recommendations and timing of applications for most crops,and special tools for nitrogen recommendations

Maize in Kenya (Photo from Dr. P. Seward).

Poor economics, as well as crop quality problems and potential pollution to soil,water and air.

To soils: unnecessary acidification.

To crops: lodging, enhanced susceptibility to diseases, quality problems.

To water: acidification, eutrophication and enhanced nitrate concentration that maylead to conflicts with the nitrate limit in drinking water.

To air: unnecessary emissions of ammonia (contributing to soil acidification andeutrophication) and nitrous oxide (increasing the greenhouse gas content in theatmosphere).

To the farmer: excessive application is an expense with no benefit.

These problems are eliminated or minimised by careful fertilizer- planning and use.

Yara has developed advisory tools and expert programs which give fertilizerrecommendations and timing of applications for most crops, and special tools fornitrogen recommendations.

Natural N input is about 113 Mt N/yAnthropogenic N amounts to ca. 140 Mt N/y

- Agriculture is responsible for 80% of theanthropogenic input (two thirds from mineralfertilizers, one third from increased growth oflegumes).

NaturalFossil fuel

35 Yara ©

Generally not.Most potential losses can be negated by adhering to good agriculturalpractice and following local fertilizer recommendation systems for optimumrates and timing of applications to meet crop need.


Do fertilizers leach to ground water?Q29

Nitrate leaching is low, at or beloweconomic optimum N application

Phosphorus, potassium, nitrogen as ammonium (NH4 +) andmicronutrients bind efficiently to soil particles, and leachinglosses are usually negligible. Most ammonium is graduallytransformed to nitrate (NO3-) by soil microbes. This naturalprocess goes on all the time except when the soil is frozen.

It is when nitrogen is in the nitrate form, (NO3-) that it is mostvulnerable to leaching as nitrate does not bind to soil particles,and moves in the soil water unless taken up by the plant rootsor soil microbes. Farmer practice can minimise the risk ofnitrate leaching by:

Avoiding nitrogen applications when heavy rain is expected- particularly in the spring. Planting winter crops or cover crops to take up post harvest nitrate residues.

Using local fertilizer recommendation systems for rates and timing so that the economic optimum rate of nitrogen is not exceeded.

Phosphorus does not readily leach, (except in exceptional circumstances, for exampleat very high soil phosphorus contents and following heavy rains that cause soil erosion).The principle routes of loss are not from fertilizer sources, but from soil surface runoff where winter applications of manures and slurry, have been applied particularlyto “high risk” fields. Notably, sloping land with potential for soil erosion, or riverbanksdamaged by livestock, which may also defecate directly into rivers.

When this occurs, lakes and rivers can become green and cloudy with enhanced algalgrowth and are referred to as eutrophic. This phenomenon causes the ecosystem todeteriorate, and can deleteriously affect fish populations.

Nutrient losses from agriculture to water may increase as a result of changes inagriculture, and where:

Fertilizer is not used at optimum rates but in excess of crop demand.More land is brought into cultivation.Wetlands with the ability to absorb nutrients before they reach watercourses aredrained and converted to agricultural land.Arable and livestock farming are separated with the concentration of animalfarming in certain regions and arable farming in others.

Source apportionment of phosphorusdischarges to Europe’s seas andpercentage reductions

00

0 t

onne

s P

/yea

r

80 -

70 -

60 -

50 -

40 -

30 -

20 -

10 -

0 -Agriculture

19852000

UWWT Industry Aquaculture

00

0 t

onne

s P

/yea

r

50 -

45 -

40 -

35 -

30 -

25 -

20 -

15 -

10 -

5 -

0 -Agriculture

Late 1980’s1995

UWWT Industry Aquaculture

North Sea

Baltic Sea

© Yara 36

Sources:North Sea progress report, 2002.Finnish Environment Institute, 2002.Black Sea Commission, 2002.Caspian Environment Programme (no date).European Environment Agency (EEA 2003).

Yiel

d of

whe

at t/

ha

leac

hing

of N

9 -

8 -

7 -

6 -

5 -

4 -

3 -

2 -

1 -

0 -0 50 100 150 200

- 90- 80- 70- 60- 50- 40- 30- 20- 10- 0

Economic optimum yield Fertilization kg N/ha Leaching kg N/ha

Source: Yara R&D trials programme.

N applied kg/ha

Urban wastewater treatment

Urban wastewater treatment

Some do, others don't.Generally all ammonium-containing fertilizers have the potential for ammoniavolatilization, but urea and anhydrous ammonia have the highest potential.

Urea can lose up to 50% of nitrogen as ammonia (NH3) through chemical transformationsafter surface spreading. In Europe the average ammonia loss from urea is about 15%.Ammonium bicarbonate – mainly used in China – is unstable and emits substantialamounts of ammonia after application.

The soil conditions are also important. Nitrogen volatilization grows with increasingsoil pH. Ammonium-containing fertilizers (particularly ammonium sulphate anddiammonium phosphate) applied to calcareous soils may result in ammonia losses.

Nitrate-based fertilizers such as ammonium nitrate, calcium ammonium nitrate andcomplex fertilizers only lose a very low percentage of the nitrogen in this manner, andnitrate fertilizers e.g. calcium nitrate have no ammonia (NH3) emissions.

The dominant source of atmospheric ammonia is farm animals and their manures. Fertilizer use only contributes about 10% of atmospheric ammonia in Western Europe and North America. Urea (and ammonium bicarbonate) may contribute to higher emissions in rice growing regions such as Asia.


Is there an increased risk of leachingwhen applying highly soluble nitrogenfertilizers?Q30If there is a balance between nitrogen applied and that removed in crops, the riskof leaching is not great.

It is important to apply the optimum rate according to goodagricultural practice. The risk of leaching is increased if excessivenitrogen is applied. The timing of nitrogen applications is alsoimportant and in many cases it is preferable to use splitapplications.

A high yielding cereal variety grown under favourable climaticconditions can yield up to ten tonnes per ha and take upbetween 270 and 300 kg of nitrogen.

Data from Baumgärtel et al.(1989).

Nitrate leaching is low at or beloweconomic optimum N application,example for winter wheat.

Yie

ld t

/ha

Soi

l nit

rate

at

harv

est

(kg

N/h

a)

N rate (kg N/ha)

10 -

9 -

8 -

7 -

6 -

5 -

4 -0 50 100 150 200 250 300

- 100

- 80

- 60

- 40

- 20

- 0

Grain yield

Soil nitrate at harvest(risk of leaching)

Do fertilizers give off ammonia which isan atmospheric pollutant?Q31

NH3

NH4+Ammonium

NO3-NitrateUrea

Urea hydrolysis Nitrification

Ammoniavolatilization

Manure

* on calcareous soils to be multiplied by 10.Based on EEA (2004): EMEP/CORINAIR Emission Inventory Guidebook - 3rd edition September 2004 UPDATE, Technical report No 30.

Emission factors (NH3-N loss as % of total applied N)

Fertilizer type

Urea

Nitrogen solutions (eg. UAN)

Ammonium sulphate & ammonium phosphate

(Calcium) ammonium nitrate

> 13˚C

20

11

2.5*

2

6 - 13˚C

17

9

2*

1.5

<6˚C

15

7

1.5*

1

Mean spring temperature

37 Yara ©


What problems does ammoniavolatilization cause?Q32Ammonia concentrations in the atmosphere are so low that they do not haveany direct toxic effects. Ammonia volatilization though, contributes to theacidification and eutrophication of land and water ecosystems, and plays a rolein the formation of fine dust.

Acidification results mainly from anthropogenic emissions of sulphur dioxide (SO2),nitrogen oxides (NOx) and ammonia (NH3) and is damaging acid-sensitive ecosystemsat a regional to continental level. In particular forests and fresh water lakes are sensitiveto acidification. The consequences range from defoliation and reduced tree vitality todeclining fish stocks and decreasing biodiversity in lakes. NH3 is responsible for 31%of the acidification effect in Europe, SO2 and NOx for 36% and 33%, respectively(EEA, 2001). The gaseous NH3 emission returns back to the surface as dry or wetdeposition partly combined with SO2 as ammonium sulphate. While most of the drydepositions of ammonia take place nearby the emission site, compounds with nitricor sulphuric acid can be transported over distances of several thousand kilometres.

Eutrophication can be defined as an undesired increase in biomass production inaquatic and terrestrial ecosystems caused by high nutrient inputs, which result in ashift in species composition. In surface waters eutrophication is particularly seriousbecause it can lead to algal blooms and the subsequent oxygen-consuming degradationprocesses, which may finally result in the death of fishes and other organisms.Ammonia emissions that deposit on water bodies and nitrate leaching are the mainanthropogenic nitrogen inputs to water. Other important nutrient inputs to wateroriginate from waste water treatment plants and industry. However, land ecosystemsmay also suffer from nutrient enrichment. Naturally nutrient poor areas with greatdiversity of plant species (e.g. certain grassland communities) that receive additionalnitrogen from the atmosphere will deteriorate in terms of biodiversity.

There is increasing concern about negative health effects of particulate matter thatcontributes to dust formation on a local to regional scale. Ammonia and sulphuremissions are the main sources of fine dust with particles of less than 2.5 micrometers(PM2.5) in diameter. The main sources for bigger particles with a diameter up to 10micrometers (PM10) are stationary combustion plants, industry and traffic (EEA,1998).

Source: ECETOC Technical Report No. 62Ammonia Emissions to Air in Western Europe.

Manure storage 34%Grazing 8%Manure spreading 32%

Application 12.5%Production 0.5%Leaf emission from crop 5%

Miscellaneous 8%

Share of different sources of ammoniaemissions in Europe

Animal husbandry

Mineral fertilizer

© Yara 38

Nitrogen turnover in soils

volatilisation

NH3

N2

NH4

binding to clay minerals

Mineralisation

immobilisation

nitrificationNO3

leaching

NO + N2 + N2O

Plantdentrification

fixation

Organic N

Is the economic optimum fertilizingintensity in conflict with environmentalconsideration?Q33No.

Life Cycle Assessment (LCA) studies of different application rates of nitrogen fertilizerhave shown that crop production at rates above the economic optimim N rate as wellas without applying N fertilizer causes the highest environmental damages.The economic optimum fertilizer rate shows only economic and social considerations.The economic fertilizing intensity is therefore preferable from a sustainability pointof view.

In the Yara authored, 2004 paper to the European Journal of Agronomy(vol 20, pp 247-264), entitled “Environmental impact assessment of agriculturalproduction systems using the life cycle assessment methodology. The theoreticalconcept of a LCA method tailored to crop production”. Yara scientist’s based atthe Hanninghof Research Centre have developed an LCA method specificallytailored to plant nutrients in arable crop production in Europe.


39 Yara ©

Inventory ofenvironmental impacts(per/t grain)

Emissions(NO3, NH3, N2O, CO2 etc)

and

Resources(Oil, gas, land etc)

Raw material extraction- Fossil fuels- Minerals

Production & transportation- Fertilizer- Pesticides- Machinery- Seeds

Arable farming- Tillage- Sowing- Plant nutrition- Plant protection- Harvest

Aggregation toeffects (per/t grain)

- Global warming- Acidification- Eutrophication- Land use- Energy consumption

EcoX value(per/t grain)

= Wheat grain

The scope of Life Cycle Assessment studies by Yara using European data

The role of fertilizers, at varying rates in terms of environmental impact

EcoX/t grain0.8 -

0.6 -

0.4 -

0.2 -

0.0 -0 96 192 288

Kg N / ha

Eutrophication(water and land)

Acidification

Global warming

Land use

Conversion to biofuel

Soil organic build-up

Food and feedstuff

Plants for biofuel

Plant residues

5 - 10 energy unitsstored in plants -due to the use of fertilizersSolar

energy

Do we gain or lose useful energy by usingmineral fertilizers?Q34


© Yara 40

1 unit of energy -for production anduse of fertilizers

We gain!

Agriculture produces energy in the form of food or feed for humans oranimals. Generally, the amount of energy stored in the harvested biomass ishigher than the energy required to produce the biomass. Fertilizers greatlyincrease this positive energy balance of agriculture, because the use ofnitrogen fertilizer enables crops to grow more biomass which in turn fixesadditional solar energy.

Fertilizer use consumes fossil fuels in order to produce food or feed, i.e. another formof energy that is not equivalent to what has been consumed. If agriculture producesenergy crops (like rape or maize) which are used to produce biodiesel or bioethanol,more fuel is produced than consumed - and optimum fertilizer supply enhances thispositive energy balance.

Energy is a central issue in agriculture. The very reason foragriculture’s existence is to supply energy to mankind. Itdoes this by converting foliar energy into biomass, which inturn supplies energy to human beings and animals in theform of food and feed. In fact, fertilizers can be considereda catalyst for capturing clean solar energy. Depending on thecrop and the yield, the plants can capture 5-10 times theamount of energy that is used in making and supplyingfertilizers. If the crop or crop residues are used for fuel, thiswill replace the use of fossil fuels and thus lead to an overallreduction of the emission of CO2 climate gases. Also, organicmatter build-up in soils by the plant residues may lead tolong term capturing of CO2.

Fertilizers increase energy

Capture of solar energy due to mineral fertilizers

GJ/

ha g

rain

140 -

120 -

100 -

80 -

60 -

40 -

20 -

0 -

-20 -zero N

GJ/ha

170 kg N/ha

+55

- 7.5

Date: Winter wheat field trials (Germany).Energy content: 15.4 GJ/t grain or straw

- 8- 7.5

7171

4.771.07.5

63.5

8.2126.015.5110.5

Grain yield (t/ha)Energy yield (GJ/ha)Energy consumption (GJ/ha)Net energy yield (GJ/ha)

Solar energycaptured in extrabiomass produceddue to fertilizer use

Solar energy inbiomass producedwithout fertilizer use

Tillage etcFertilizer (170 kg N/ha)

How much energy (fossil fuel) does ittake to make one kg of nitrogen fertilizer?Q35Modern fertilizer plants utilize natural gas or other gases like propane or ethylene.In the most efficient plants it takes 0.6 kg of natural gas to make one kilo ofnitrogen as ammonia or ammonium nitrate, and 0.75 kg to make urea. This isequivalent to 0.8 and 0.93 kg respectively, of fuel oil. Most of the energyconsumption in the nitrogen fertilizer chain is during the production phase.

The energy efficiency in N fertilizer production has been significantly improved sincethe beginning of the 20th century. Modern fertilizer factories are close to the theoreticalminimum of energy consumption.


Production40 GJ/t N

91% 2% 7%

Logistics and transport1 GJ/t N

Application3 GJ/t N

450 -

400 -

350 -

300 -

250 -

200 -

150 -

100 -

50 -

0 -

Reduced energy consumption

GJ/

t N

1910 1915 1930 1950 1960 1975 2000

Birkeland-Eyde electric arc method

Theoretical minimum

Cyanamid method

Haber-Bosch synthesis

Steam reformingnatural gas

41 Yara ©

Are fertilizers free of toxic substancesand safe to handle?Q36


Yara has a complete set of Safety Data Sheets for every product to ensure safehandling.

Fertilizer nutrients are not toxic per se and do not contain toxic substances. There areinternationally agreed criteria to define a substance which is regarded as toxic andrequires a warning label. Fertilizers (except for anhydrous and concentrated ammoniasolutions) are not classified as toxic.

However, most mineral fertilizers are soluble salts, and fertilizer dust on skin willdissolve in sweat and give a concentrated salt solution that can cause irritation,dehydration or skin damage.

Some fertilizers can decompose in a fire to produce fumes that are toxic due to thecontent of chlorine and /or nitrogen oxides. Fertilizer in storage should be separatedfrom sources of heat and combustible materials.

Ammonium nitrate is a recognized oxidizing agent and there are special requirementsfor its safe handling and storage. Local regulations cover these aspects in countrieswhere ammonium nitrate is used.

Yara has a clear policy for health, safety, environment, quality and productstewardship in all its areas of operation. Further information, including SafetyData Sheets can be found on the Company’s website www.yara.com

42 Yara ©

1. Identification of the substance/preparation

and of the company/undertaking

Identification of the substance or preparation and of the

company/undertaking

Product name: SDS Group 4.1

Synonyms:

Solid NPK, NP, NK - not more than 70% ammonium nitrate, NOT

capable of cigar burning, without limestone.

Use of the substance/preparation:

FertilizerCompany/undertaking identification, Manufacturer / Supplier:

Yara UK Limited

Immingham

North East Lincolnshire

DN40 2NS UK

T: +44 (0) 1469 554600

F: +44 (0) 1469 571624

Emergency telephone number:

+44 (0) 1865 407333

National Chemical Emergency Centre (NCEC)

2. Composition/information on ingredients

Substance/preparation:

Preparation

Within the present knowledge of the supplier, this product does not

contain any hazardous ingredients in quantities requiring reporting in

this section, in accordance with EU regulations or National regulations.

May contain some or all of the following:- ammonium sulphate, urea,

mono and di ammonium phosphate, single superphosphate, triple

superphosphate, phosphate rock, potassium chloride, potassium sulphate,

ureaformaldehyde, inert fillers such as sand and coating materials such

as oil, amine, clay or talc.

3. Hazards identification

The preparation is not classified as dangerous according to Directive

1999/45/EC and its amendments.

See section 11 for more detailed information on health effects and

symptoms.4. First aid measures

Inhalation:

Avoid breathing dust. If inhaled, remove to fresh air.

Ingestion:

If large quantities of this material are swallowed, call a physician

immediately. Do NOT induce vomiting unless directed to do so by

medical personnel. Never give anything by mouth to an unconscious

person.Skin Contact:

Avoid prolonged or repeated contact with skin. After handling, always

wash hands thoroughly with soap and water. Get medical attention if

irritation develops.

Eye contact:

In case of contact with eyes, rinse immediately with a copious amount

of water. Get medical attention if irritation occurs.


symptoms.

5. Fire-fighting measures

Extinguishing media:

Use water only in flooding quantities. Do not release runoff from fire to

sewers waterways. Open doors and windows to give maximum ventilation.

Special exposure hazards:

Avoid breathing dusts, vapours or fumes from burning materials. In

case of inhalation of decomposition products in a fire, symptoms may

be delayed. Fire-fighters should wear self-contained positive pressure

breathing apparatus (SCBA) and full turnout gear.

Hazardous thermal decomposition products

Potential Products: Carbon oxides (CO, CO2) and water, nitrogen oxides

(NO, NO2 ...), sulphur oxides (SO

2, SO3, etc.), halogenated compounds

and phosphates. Avoid breathing dusts, vapours or fumes from burning

materials. In case of inhalation of decomposition products in a fire,

symptoms may be delayed.

6. Accidental release measures

Personal Precautions:

Use suitable protective equipment (Section 8). Follow all fire fighting

procedures (Section 5).

Environmental precautions and clean-up methods:

Minimize contact of spilled material with soils to prevent runoff to surface

waterways.Use a tool to scoop up solid or absorbed material and place into appropriate

labeled waste container. Absorb with dry sand or other noncombustible

material. Avoid creating dusty conditions and prevent wind dispersal. Keep

out of waterways. See Section 13 for Waste Disposal Information.

Note: see section 8 for personal protective equipment and section 13 for

waste disposal.7. Handling and storage

Handling:

Avoid creating dust when handling and avoid all possible sources of ignition

(spark or flame). Avoid contamination by any source including metals, dust

and organic materials.

Storage: Store and use away from heat, sparks, open flame, or any other

ignition source. Avoid contact with combustible materials. On farm keep

away from hay, grain, diesel, etc.

8. Exposure controls/personal protection

Occupational exposure limits:

Total inhalable dust - 10 mg/m3

Respirable dust - 4 mg/m3

Exposure controls

Respiratory protection:

Use a properly fitted, particulate filter respirator complying with an approved

standard if a risk assessment indicates this is necessary. Respirator selection

must be based on known or anticipated exposure levels, the hazards of

the product and the safe working limits of the selected respirator.

Hand protection:

Chemical-resistant, impervious gloves or gauntlets complying with an

approved standard should be worn at all times when handling chemical

products if a risk assessment indicates this is necessary.

Eye protection:

Use dust goggles if high dust concentration is generated.

Skin protection:

Personal protective equipment for the body should be selected based on

Safety Data Sheet

Conforms to 91/155/EEC - 2001/58/EC - United Kingdom (UK)4.1

Safety Data Sheet

Conforms to 91/155/EEC - 2001/58/EC - United Kingdom (UK)

3.1

1. Identification of the substance/preparation

and of the company/undertaking

Identification of the substance or preparation and of the

company/undertakingProduct name: SDS Group 3.1

Synonyms:Solid N - less than 70% ammonium nitrate, and not more than 0.4%

combustibles or less than 80% ammonium nitrate with dolomite, inert

filler or less than 45% ammonium nitrate with ammonium sulphate

and not more than 0.4% combustibles.

Use of the substance/preparation:

FertilizerCompany/undertaking identification, Manufacturer / Supplier:

Yara UK LimitedImminghamNorth East LincolnshireDN40 2NS UKT: +44 (0) 1469 554600

F: +44 (0) 1469 571624Emergency telephone number:

+44 (0) 1865 407333National Chemical Emergency Centre (NCEC)

2. Composition/information on ingredients

Substance/preparation:PreparationWithin the present knowledge of the supplier, this product does not

contain any hazardous ingredients in quantities requiring reporting in

this section, in accordance with EU regulations or National regulations.

May contain some of the following ingredients in addition to ammonium

nitrate:- ammonium sulphate, dolomite, gypsum (Calcium Sulphate)

inert fillers such as sand, coating materials such as oil, amino, clay or

talc, secondary nutrients and/or micro-nutrients.

3. Hazards identificationThe preparation is not classified as dangerous according to Directive

1999/45/EC and its amendments.See section 11 for more detailed information on health effects and

symptoms.

4. First aid measuresInhalation:Avoid breathing dust. If inhaled, remove to fresh air.

Ingestion:If large quantities of this material are swallowed, call a physician

immediately. Do NOT induce vomiting unless directed to do so by

medical personnel. Never give anything by mouth to an unconscious

person.Skin Contact:Avoid prolonged or repeated contact with skin. After handling, always

wash hands thoroughly with soap and water. Get medical attention if

irritation develops.Eye contact:In case of contact with eyes, rinse immediately with a copious amount

of water. Get medical attention if irritation occurs.


5. Fire-fighting measuresExtinguishing media:Use water only in flooding quantities. Do not release runoff from fire to

sewers waterways. Open doors and windows to give maximum ventilation.

Special exposure hazards:

Avoid breathing dusts, vapours or fumes from burning materials. In

case of inhalation of decomposition products in a fire, symptoms may

be delayed. Fire-fighters should wear self-contained positive pressure

breathing apparatus (SCBA) and full turnout gear.

Hazardous thermal decomposition products

These products are nitrogen oxides (NO, NO2...). Avoid breathing dusts,

vapours or fumes from burning materials. In case of inhalation of

decomposition products in a fire, symptoms may be delayed.

6. Accidental release measures

Personal Precautions:Use suitable protective equipment (Section 8). Follow all fire fighting

procedures (Section 5).Environmental precautions and clean-up methods:

Minimize contact of spilled material with soils to prevent runoff to surface

waterways.Use a tool to scoop up solid or absorbed material and place into appropriate

labeled waste container. Absorb with dry sand or other noncombustible

material. Avoid creating dusty conditions and prevent wind dispersal. Keep

out of waterways. See Section 13 for Waste Disposal Information.

Note: see section 8 for personal protective equipment and section 13 for

waste disposal.7. Handling and storage

Handling:Avoid creating dust when handling and avoid all possible sources of ignition

(spark or flame). Avoid contamination by any source including metals, dust

and organic materials.Storage: Store and use away from heat, sparks, open flame, or any other

ignition source. Avoid contact with combustible materials. On farm keep

away from hay, grain, diesel, etc.8. Exposure controls/personal protection

Occupational exposure limits:

Total inhalable dust - 10 mg/m3 Respirable dust - 4 mg/m3Exposure controlsRespiratory protection:

Use a properly fitted, particulate filter respirator complying with an approved

standard if a risk assessment indicates this is necessary. Respirator selection

must be based on known or anticipated exposure levels, the hazards of

the product and the safe working limits of the selected respirator.

Hand protection:Chemical-resistant, impervious gloves or gauntlets complying with an

approved standard should be worn at all times when handling chemical

products if a risk assessment indicates this is necessary.

Eye protection:Use dust goggles if high dust concentration is generated.

Skin protection:Personal protective equipment for the body should be selected based on

the task being performed and the risks involved.

Safety Data Sheet

Conforms to 91/155/EEC - 2001/58/EC - United Kingdom (UK)

1.11. Identification of the substance/preparationand of the company/undertaking

Identification of the substance or preparation and of thecompany/undertakingProduct name: SDS Group 1.1

Synonyms:Solid straight AN - must be not less than 20% N, may containammonium sulphate, magnesium nitrate, dolomite, inert fillers.

Use of the substance/preparation:Fertilizer

Company/undertaking identification, Manufacturer / Supplier:Yara UK LimitedImminghamNorth East LincolnshireDN40 2NS UKT: +44 (0) 1469 554600F: +44 (0) 1469 571624

Emergency telephone number:+44 (0) 1865 407333National Chemical Emergency Centre (NCEC)

2. Composition/information on ingredientsSubstance/preparation:PreparationWithin the present knowledge of the supplier, this product does notcontain any hazardous ingredients in quantities requiring reporting inthis section, in accordance with EU regulations or National regulations.

May contain some of the following ingredients in addition to ammoniumnitrate:- ammonium sulphate, magnesium nitrate or dolomite, inertfillers such as sand, coating materials such as oil, amine, clay or talc.

3. Hazards identificationThe preparation is not classified as dangerous according to Directive1999/45/EC and its amendments.

See section 11 for more detailed information on health effects andsymptoms.

4. First aid measuresInhalation:Avoid breathing dust. If inhaled, remove to fresh air.

Ingestion:If large quantities of this material are swallowed, call a physicianimmediately. Do NOT induce vomiting unless directed to do so bymedical personnel. Never give anything by mouth to an unconsciousperson.

Skin Contact:Avoid prolonged or repeated contact with skin. After handling, alwayswash hands thoroughly with soap and water. Get medical attention ifirritation develops.

Eye contact:In case of contact with eyes, rinse immediately with a copious amountof water. Get medical attention if irritation occurs.

See section 11 for more detailed information on health effects andsymptoms.

5. Fire-fighting measuresExtinguishing media:Use water only in flooding quantities. Do not release runoff from fire tosewers waterways. Open doors and windows to give maximum ventilation.

Special exposure hazards:Avoid breathing dusts, vapours or fumes from burning materials. Incase of inhalation of decomposition products in a fire, symptoms maybe delayed. Fire-fighters should wear self-contained positive pressurebreathing apparatus (SCBA) and full turnout gear.

Hazardous thermal decomposition productsThese products are nitrogen oxides (NO, NO2...). Avoid breathing dusts,vapours or fumes from burning materials. In case of inhalation ofdecomposition products in a fire, symptoms may be delayed.

6. Accidental release measuresPersonal Precautions:Use suitable protective equipment (Section 8). Follow all fire fightingprocedures (Section 5).

Environmental precautions and clean-up methods:Minimize contact of spilled material with soils to prevent runoff to surfacewaterways.

Use a tool to scoop up solid or absorbed material and place into appropriatelabeled waste container. Absorb with dry sand or other noncombustiblematerial. Avoid creating dusty conditions and prevent wind dispersal. Keepout of waterways. See Section 13 for Waste Disposal Information.

Note: see section 8 for personal protective equipment and section 13 forwaste disposal.

7. Handling and storageHandling:Avoid creating dust when handling and avoid all possible sources of ignition(spark or flame). Avoid contamination by any source including metals, dustand organic materials.

Storage:Store and use away from heat, sparks, open flame, or any other ignitionsource. Avoid contact with combustible materials. On farm keep away fromhay, grain, diesel, etc.

8. Exposure controls/personal protectionOccupational exposure limits:Total inhalable dust - 10 mg/m3

Respirable dust - 4 mg/m3

Exposure controls

Respiratory protection:Use a properly fitted, particulate filter respirator complying with an approvedstandard if a risk assessment indicates this is necessary. Respirator selectionmust be based on known or anticipated exposure levels, the hazards ofthe product and the safe working limits of the selected respirator.

Hand protection:Chemical-resistant, impervious gloves or gauntlets complying with anapproved standard should be worn at all times when handling chemicalproducts if a risk assessment indicates this is necessary.

Eye protection:Use dust goggles if high dust concentration is generated.

Skin protection:Personal protective equipment for the body should be selected based on

Safety data sheets.

What is the Company’s policy regardingfertilizers and the wider environment?Q37


Yara is committed to continuously improving and developing products, servicesand advice so that the company’s fertilizer products actively:

Contribute to a sustainable agriculture.

Are responsibly used in line with best agricultural practice

Utilize best available technology in production

Meet best agricultural practice.

Comply with legislation.

The responsibility for how the product is actually used remains with the farmer.

Fertilizers are biologically active compounds, and as such, they can influence theenvironment. It is the Company’s policy to reduce environmental impacts along theentire life cycle of a fertilizer, i.e. from production through to the use of our products.

Great improvements have been achieved in production technologies to minimiseenergy use and emissions.

Fertilizers correctly used are environmentally benign products. They are not poisonousto soil or water, and consist of naturally occurring plant nutrients that are necessaryfor maintaining soil fertility and securing adequate and sustainable food production.

The main environmental concerns arise through the irresponsible use of fertilizers.

The company promotes the responsible and correct use of fertilizers throughout thesupply chain, with adherence to good agricultural practices. The understanding of howour products behave in the environment is important to Yara, enabling avoidance ofrecommendations that could have unnecessary environmental effects. Investmentin R & D, adoption of novel technologies and the development of tools for optimalfertilizer use (taking full account of all nutrient sources) works to ensure minimalenvironmental impact.

The Company has for many yearspublished guidelines and has developedexpert systems for the end user whichproduce fertilizer recommendations likethe N-Tester and N-Sensor and Yara Plan.

The Company published a guidebook onenvironmental issues relating to fertilizeruse in 1990: (“Agriculture and Fertilizers”;private publisher), which was updated andextended in 1999 (“Agriculture, Fertilizersand the Environment”; CABI publishing).

Fertilizers, agriculture and sustainability

43 Yara ©

For further information please contact:Yara International ASABygdøy allé 2,N-0202, Oslo, Norwaywww.yara.com

Documents

Important Questions on Fertilizer and the Environment