׉?4ׁB!בCטu׉׉ 7cassandra://awCEC_vwyTADQmY-VqXmnfyRcuE57wxFi7L1y_ReJ6c`׉ 7cassandra://6I5jVh1eFgvVRHVAVL4ufPxN4dS904se44X6Kuqm46MU`R׉ 7cassandra://fGJlMTK9DPac9iBBxt01cFBGg0K9qf_pVSXNss3VaXc`̴׉ 7cassandra://eiuy16wKYduXjcZIhSBMgStNQt04E2Yssk4TO26hPrAͫTl͠VhOX7RiSנVhOX7RiR xQP9׉H͠VhOY7Riq׉E8 ׉ 7cassandra://I7yY98kvit9DOv-wdY8jqEgqyHwR2MsI47hDVFFevSY*L`̴VhOY7Rir׉EqLiving on air From air to plant nutrient Producing nutrient nitrogen We are surrounded by an endless amount of nitrogen. Almost 80% of the Earth’s atmosphere is made of gaseous nitrogen, known as atmospheric nitrogen or N2. We breathe it in, but our bodies cannot absorb it. It’s as if we were bobbing around in a boat on an immeasurable ocean, surrounded by an endless amount of water that we’re unable to drink. To make atmospheric nitrogen suitable for consumption, it has to be “fixed.” The process of fixation produces nutrient nitrogen, which serves as a plant nutrient. In nature, nitrogen is fixed both in the atmosphere and in the soil. Lightning strikes, for example, will cause some fixation of atmospheric nitrogen, with rain then carrying the result, nutrient nitrogen, to the soil. When bacteria in the soil work together with certain plants, especially clover, they also fix atmospheric nitrogen. Once again, the resulting nutrient nitrogen ends up in the soil. Plants absorb this nitrogen and use it to synthesize proteins and other substances, making it available to animals and people who eat the plants. I 9 ׉ 7cassandra://JSYAbEjzjVa3gloOwgsuZHll8C1TiKRZXjZdQWZzzro`̴VhOY7RisVhOY7RirvבCטu׉׉ 7cassandra://ZfmHvtumfbXfR2Jg-a1rVshVPS2cNqrypIn-2tik8nw)`׉ 7cassandra://Gu9NL_nLyRV1gqlAglHDgN44hRxjq35RXXDgEeTq85oL6`R׉ 7cassandra://C3YohcgPFsuNxPqbhSm4_QIflSFfpgABNOGGf37UNTg`̴׉ 7cassandra://fdcLClPdFPVBd9XTw4Pmti08EAJTyE4jvYJu1GaZ8ccͨs͠VhOY7Rivטu׉׉ 7cassandra://5n8S6p6XUGO0lHRjhK_Z6al_WEuUjmEK_fbcVl4X-lc`׉ 7cassandra://45uxJs4-7uPi27WHxTYM8XAqQ6HBxJ8DQfzX7SXKfd0Dy`R׉ 7cassandra://oZNOH21POdaeXWTur29PTlgPgz4JXh3_DwnO0IZMoLoR`̴׉ 7cassandra://XjCvGeqwwVKZR7QUrbLVoQ_7PCXQZnxg8RcuM0fWjbU͠VhOY7Riw׉E10 ׉ 7cassandra://C3YohcgPFsuNxPqbhSm4_QIflSFfpgABNOGGf37UNTg`̴VhOY7Rix׉EeLiving on air From nutrient back to air Loss of nutrient nitrogen In farming, most of the nutrient nitrogen is lost during harvest. Protein-rich – and therefore nitrogen-rich – plants are simply removed from the land. Farmers obviously need to replace the nutrient nitrogen they have removed in order to restore the fertility of the soil. That is not enough, however. Besides the nutrient nitrogen “lost” to the harvest, nitrogen is also lost to the air and soil in natural processes. Although the soil contains bacteria that convert atmospheric nitrogen into nutrient nitrogen, bacteria that do precisely the opposite are even more common. They convert the nitrogen back into a gas that evaporates into the air, so that it is once more unavailable for plant growth. Nutrient nitrogen that plants can absorb is mobile. The portion that the plant has not yet absorbed can be flushed away into the soil in heavy rain. Depending on the circumstances, part of it will leach from the soil into the ground water and surface water. The loss of valuable nutrient nitrogen is both natural and unavoidable. The nature and scale of nitrogen loss depend on the climate, the weather, the type of crop, the type of soil, and the degree of fertilization efficiency. The scale of the loss is roughly comparable to the amount of nitrogen contained in the crops removed in the harvest. I 11 ׉ 7cassandra://oZNOH21POdaeXWTur29PTlgPgz4JXh3_DwnO0IZMoLoR`̴VhOY7RiyVhOY7RixvבCטu׉׉ 7cassandra://X6fh6W-KAqKfYkw70UNZcvMEMOLft2W8iDpLNkuZMME;`׉ 7cassandra://Yxb-5b9i3SpBHUTZ7rD-EHyz3cHSCSoe3IHA__FC1Dc:I`R׉ 7cassandra://fMI2TKeWivVsGnrNfbwf8QzTMY0DRrCOs5uVXk3T20s`̴׉ 7cassandra://ICTdfxUtAmQ5ygZQe8oz_v4BdElk_gOmFcSf_9RHQnc6k͠VhO[7Ri{טu׉׉ 7cassandra://MPiFEywVpWj2Y7wkzxpU0doJjywFSRaUme7Eldo9T-I`׉ 7cassandra://U17osY1bFCQP-zhx62NLwDAMYJYkZzc-aeg_Dni_wJIHr`R׉ 7cassandra://UF031fZvIxVStyhpavGoBaStPBXl2ms0jfNutxdLEEYf`̴׉ 7cassandra://5JLwOzHV9wkyrwoUcpf9TdpSrdpfKMN5870_6Tndwng,͠VhO[7Ri|׉E12 N N N N ׉ 7cassandra://fMI2TKeWivVsGnrNfbwf8QzTMY0DRrCOs5uVXk3T20s`̴VhO[7Ri}׉E"Living on air I 13 Keeping the nitrogen cycle in balance with supplementary nitrogen N Almost 80% of the Earth’s atmosphere is made of gaseous or atmospheric nitrogen. To make atmospheric nitrogen suitable for consumption, it has to be “fixed.” In nature, nitrogen fixation takes place in the atmosphere and in the soil. Atmospheric nitrogen can be fixed in the atmosphere by lightning strikes, for example. Rain then carries it to the soil in the form of nutrient nitrogen. In the soil, bacteria fix atmospheric nitrogen. N Nutrient nitrogen disappears when crops are removed from the land. In addition, natural processes cause it to disappear into the air, soil and water. To meet the world’s growing demand for food, early twentieth-century scientists developed a method for producing nutrient nitrogen. The fixation of atmospheric nitrogen now occurs on an industrial scale, with mineral fertilizers as the product. Together with the nutrient nitrogen produced by natural fixation in the atmosphere and soil, they make an unbeatable combination. ׉ 7cassandra://UF031fZvIxVStyhpavGoBaStPBXl2ms0jfNutxdLEEYf`̴VhO[7Ri~VhO[7Ri}vבCטu׉׉ 7cassandra://tJwF_6XGtyD9Sz4HxexOeupW0e97DUtQmCeBwnj-86oͥ`׉ 7cassandra://r7_UhGb1K5l1Su-qDc3mMEYgrqA0rLVLdk--5_D5Oyg,`R׉ 7cassandra://WAHKbXfzEENzGSoXjWzwaIkiRK4pUCHnsSks18A-pAg`̴׉ 7cassandra://k0wkS9TjQmnfwA5n2HUcSO4NHh_pPjprwVsR95I_7Lw|͠VhO[7Riրטu׉׉ 7cassandra://jqpBKw-ro2kOJkPBjZfmELTsKQk_Mp11ew4IVi2qJIs/`׉ 7cassandra://o3igTzYJr7ElLSF81AGgZBGj3madMPQU5hfisLShTHI8S`R׉ 7cassandra://dvVelwc8ewpHhkp_OcvheXp45joIFhydWrvr0W0QvPI`̴׉ 7cassandra://BCrHkjKC97ff73XJ5jvcfKWNDvy3ZtfTFRZk2Ysd9JIJ͠VhO[7Riց׉Ed14 ,, Water, water, everywhere nor any drop to drink ,, Samuel Taylor Coleridge, English poet, 1798 ׉ 7cassandra://WAHKbXfzEENzGSoXjWzwaIkiRK4pUCHnsSks18A-pAg`̴VhO[7Riւ׉ELiving on air I 15 Pulled out of thin air Adding nutrient nitrogen Let’s go back to our little boat bobbing around on the ocean. We’re surrounded by an endless amount of water, and yet we’re thirsty. Our water bottle is empty. Fortunately it starts to rain – but not enough to fill our bottle. We have to come up with something clever. The same is true of nitrogen. We are surrounded by it, and yet we cannot consume it. To do that, we first have to convert it to nutrient nitrogen. The amount of nutrient nitrogen available in natural sources (lightning strikes, soil bacteria) has always been small, but until quite recently it was enough to feed the world population. That was largely thanks to farmers, who are preeminent nitrogen experts. Intent on improving their crops and increasing their harvests, farmers started using nutrient nitrogen many centuries ago, in the form of bird droppings, farmyard dung, and compost. They also let fields lie fallow to “save up” nutrient nitrogen. ׉ 7cassandra://dvVelwc8ewpHhkp_OcvheXp45joIFhydWrvr0W0QvPI`̴VhO[7RiփVhO[7RiւvבCטu׉׉ 7cassandra://RBJNUXU8VIG5lrS168qi-iYUV5HqUkDCMbLewxi4Xqs`׉ 7cassandra://wGQAcQJ4xer1IFhNSc7fAf7aD1Sxmca64SsnN3IJ4ici`R׉ 7cassandra://HNIJpAY_EHYLibHwTs3SRTkduWiZ3DNovzi-aevzZe4&`̴׉ 7cassandra://biiz_qVKCVmxrE7W_wiIr4Mb_rcJ-N8PKcDzGW6pUUE!͠VhO[7Riօטu׉׉ 7cassandra://iiYkDJlVW1lp3eFjuS6NJAgI5xpWF3Rkq66NHpyIPhQ`׉ 7cassandra://08n7b3DQMDOFj7_X47RkAWjsfoqf6x-LdQ1otzOD-wo0?`R׉ 7cassandra://LOgLyNSvNKrVDGCmuM4TCVMXG4PA_jcrZFZ3CRhyLBc `̴׉ 7cassandra://R_9j4O_WJqQ0upyaZrIPRunvC1DTp3Nc03nU9JmFb8sb͠VhO[7Riֆ׉E16 ׉ 7cassandra://HNIJpAY_EHYLibHwTs3SRTkduWiZ3DNovzi-aevzZe4&`̴VhO[7Riև׉ELiving on air I 17 Nutrient nitrogen no longer comes only from natural sources By the end of the eighteenth century, population growth had led to a shortage of nutrient nitrogen. There simply wasn’t enough to meet the rising global demand for food. In the second half of the nineteenth century, guano – the dried excrement of seabirds – became popular worldwide as an extra source of nutrient nitrogen. It could not solve the manure shortage problem, however. It was time for a bit of cleverness. In the early twentieth century, two researchers came up with the eponymous Haber-Bosch process for the mineral fixation of atmospheric nitrogen. This innovation is still regarded as one of the greatest inventions of all time. The Haber-Bosch process fixes atmospheric nitrogen on an industrial scale with hydrogen obtained from natural gas or electricity. The nutrient nitrogen it produces is used as plant nutrition in the form of mineral fertilizer. ׉ 7cassandra://LOgLyNSvNKrVDGCmuM4TCVMXG4PA_jcrZFZ3CRhyLBc `̴VhO[7RiֈVhO[7RiևvבCטu׉׉ 7cassandra://8JYajx3r437SNdIsbfUaRUuu1Z2Z9unO2jkAHRgokb0`׉ 7cassandra://JDJkAkwL9thz50oHnS6YTFmq51J9PoEoTLCkufGhEmo^`R׉ 7cassandra://4niMnL4mwrK6aoarSq3pcCTJ1XvG3LCDoEcEssBpvOA&!`̴׉ 7cassandra://UGJSWjns7gKhRjlNyKQIHYhGTsbWLsNTQjOMNzOckX4Ɓ͠VhO[7Ri֊טu׉׉ 7cassandra://mVc7D2LBjxU2yV3RoZ4lld1iBf8gvg2JQXoP3nNsdSI`׉ 7cassandra://7jV7buNCALRLENfvDRa7Q_5ERpUsvr8MdBf-PLyXKrwJ`R׉ 7cassandra://SG1UnRWoBYZ4IFau6mkX8bcfrtgo40eBEfu-72lpLo0 `̴׉ 7cassandra://pltjNoUOmSineoDOPytEwPoesWNL5dwQsc85XFSRjrc!͠VhO\7Ri֋׉E18 ׉ 7cassandra://4niMnL4mwrK6aoarSq3pcCTJ1XvG3LCDoEcEssBpvOA&!`̴VhO\7Ri֌׉ELiving on air I 19 Ready for the future A hundred years have passed and we now share our world with more than seven billion people. According to forecasts, the Earth’s nine billionth inhabitant will be born in 2050. Our food production cannot lag behind population growth. If we depended solely on the nutrient nitrogen produced by lightning strikes and soil bacteria, our Earth would only be able to support four billion people. Much of our diet would be vegetarian and we would have to take a considerable amount of farmland out of production every year so that we could save up nutrient nitrogen by growing clover. The natural world would suffer because we would need to reclaim much more land for farming. Fertilizers are therefore inevitable in our day and age. In theory, we can produce an endless amount of nutrient nitrogen. However, we need to be economical in our use. Nitrogen fixation takes a lot of energy, and excessive use of nutrient nitrogen would be harmful to the environment. Today’s efficient farming methods allow us to achieve high crop yields while maintaining the long-term fertility of our soil. The key factor in all this is optimal fertilization: organic manure as the basis, supplemented by the smart use of mineral fertilizers. Mineral fertilizers help plants to absorb nitrogen efficiently, and organic manure ensures that nutrient nitrogen is properly recycled. It’s an unbeatable combination. Adding nutrient nitrogen is both efficient and economical. It makes perfect sense. ׉ 7cassandra://SG1UnRWoBYZ4IFau6mkX8bcfrtgo40eBEfu-72lpLo0 `̴VhO\7Ri֍VhO\7Ri֌vבCטu׉׉ 7cassandra://6OPc_QnggEzs0iDgZyitVNCLq49VJMbc3109m5AIsgwC`׉ 7cassandra://xbXvXJjUCGn0p9eeYQ0W5A8n_GwH0AzyFh04E8YT8nQ)`R׉ 7cassandra://6TrqP3BHPhrxlQACfFZOwiIBkf9FGUETuGChB1IcKow `̴׉ 7cassandra://tk49Scli-KLazKcoPCsNfZH4pB_JK2T6JqHJSskWcyU2͠VhO\7Ri֓טu׉׉ 7cassandra://hzZgGzfbLaoV19r55aTidMmDej9GMV1HwNHLtmZZQNM\`׉ 7cassandra://VDMuRzOJ0xxuRONt1aOuOOmgc_E8cPf2J49ocK18xZEp`R׉ 7cassandra://EwMvIdjfSWzagSZrojBDAOhQJtzuzjinh44uZbWbM7k&`̴׉ 7cassandra://zySjJiJ5hx8aZRn7sAn967pnlLidqzJqhBFclwEOTLA͠VhO\7Ri֔נVhO\7Ri֏:U>9׉Hhttp://edepot.wur.nl/329671Gׁ ׁ rנVhO\7Ri֐:(U"9׉H(http://www.thomashager.net/recent-books/Gׁ ׁ rנVhO\7Ri֑:GU"9׉Hhttp://www.fao.org/home/en/Gׁ ׁ rנVhO\7Ri֒:eU29׉H!http://www.fertilizerseurope.com/Gׁ ׁ r׉EP20 About this publication Publisher OCI Nitrogen B.V. Mijnweg 1 6167 AC Geleen The Netherlands tel. + 31 46 7020111 www.ocinitrogen.com Editors Elisabeth Koot, Jan Jaap Nusselder Translation Balance, Amsterdam/Maastricht Sources Schröder, J.J. (2014) The Position of Mineral Nitrogen Fertilizer in Efficient Use of Nitrogen and Land: A Review. Natural Resources, 5, 936-948 Hager, T. (2008) The Alchemy of Air, Harmony/Crown Food and Agriculture Organization of the United Nations (FAO) Fertilizers Europe (represents the largest fertilizer manufacturers in Europe) Postbus 601 6160 AP Geleen Disclaimer OCI Nitrogen is making the data in this publication available for information purposes only. Although the data has been compiled to the best of its knowledge and is based on recent information, OCI Nitrogen accepts no liability in this connection. Although OCI Nitrogen has reviewed the accuracy and completeness of the data and information provided in this publication with the greatest possible care, it does not guarantee that they are without error or flaws. OCI Nitrogen accepts no responsibility whatsoever for any damage that may arise owing to the use, incompleteness or inaccuracy of the information offered in this publication. No rights may be derived from the information in this publication. The copyright in this publication rests with OCI Nitrogen or third parties who have consented to make material or images available to OCI Nitrogen. Third parties are prohibited from disclosing or reproducing any part of this publication without the prior consent of OCI Nitrogen. © 2015 OCI Nitrogen B.V. ׉ 7cassandra://6TrqP3BHPhrxlQACfFZOwiIBkf9FGUETuGChB1IcKow `̴VhO\7Ri֕׉E׉ 7cassandra://EwMvIdjfSWzagSZrojBDAOhQJtzuzjinh44uZbWbM7k&`̴VhO\7Ri֖VhO\7Ri֕vבCטu׉׉ 7cassandra://U1-9koDDZV0GJhDDNXxI1Cf3DZXU064SNa2DBoEc9q8`׉ 7cassandra://QQpllOLagm9IXJ6Sk1RCONqmO092Kpk7VoVo49Mb_sA'`R׉ 7cassandra://lpxvsVnq33-md5KCILc96wsl8iOq8FXh2k2zZSswToc `̴׉ 7cassandra://kh0kbJcgQ5CAdXC86kA5NRprsQXKM2Cdgv9T2nbeHNg#͠VhO\7Ri֚נVhO\7Ri֘YQP9׉H