Editing Potash (section)

===Fertilizers===
Potassium is the third major plant and crop nutrient after [[nitrogen]] and [[phosphorus]]. It has been used since [[Ancient history|antiquity]] as a [[soil]] [[fertilizer]] (about 90% of current use).<ref name=usgs/> Fertilizer use is the main driver behind potash consumption, especially for its use in fertilizing crops that contribute to high-protein diets.<ref name=":02" />{{Rp|page=23}} As of at least 2010, more than 95% of potash is mined for use in agricultural purposes.<ref name=":02" />{{Rp|page=24}}

Elemental potassium does not occur in nature because it reacts violently with water.<ref name="HollemanAF">{{cite book|publisher = Walter de Gruyter|year = 1985|edition = 91–100|isbn = 978-3-11-007511-3|title = Lehrbuch der Anorganischen Chemie|author = Arnold F. Holleman, Egon Wiberg and Nils Wiberg|chapter = Potassium| language = de}}</ref> As part of various compounds, potassium makes up about 2.6% of the [[Earth's crust]] by mass and is the seventh most abundant element, similar in abundance to sodium at approximately 1.8% of the crust.<ref name="Greenwood">{{cite book|last=Greenwood|first= Norman N|year=1997|title=Chemistry of the Elements |url=https://archive.org/details/chemistryelement00earn_612|url-access=limited|edition=2|place=Oxford|publisher= Butterworth-Heinemann|isbn=978-0-08-037941-8|page=[https://archive.org/details/chemistryelement00earn_612/page/n89 69]}}</ref> Potash is important for agriculture because it improves water retention, yield, nutrient value, taste, color, texture<ref name=":02" />{{Rp|page=24}} and disease resistance of food crops. It has wide application to fruit and vegetables, rice, wheat and other grains, sugar, corn, soybeans, [[palm oil]] and cotton, all of which benefit from the nutrient's quality-enhancing properties.<ref>[http://www.activex.com.au/reports/2008-09/AIV_20081114_ASX_Announ_Potash_Outlook.pdf Potash Price Close to all time highs – Future Outlook] {{webarchive|url=https://web.archive.org/web/20090918050005/http://www.activex.com.au/reports/2008-09/AIV_20081114_ASX_Announ_Potash_Outlook.pdf |date=2009-09-18 }}. ASX Release (14 November 2008). activex.com.au. Retrieved on 2013-06-21.</ref>

Demand for food and animal feed has been on the rise since 2000. The [[United States Department of Agriculture]]'s [[Economic Research Service]] (ERS) attributes the trend to average annual population increases of 75&nbsp;million people around the world. Geographically, economic growth in Asia and Latin America greatly contributed to the increased use of potash-based fertilizer. Rising incomes in developing countries also were a factor in the growing potash and fertilizer use. With more money in the household budget, consumers added more meat and dairy products to their diets. This shift in eating patterns required more acres to be planted, more fertilizer to be applied and more animals to be fed—all requiring more potash.

After years of trending upward, fertilizer use slowed in 2008. The worldwide economic downturn is the primary reason for the declining fertilizer use, dropping prices, and mounting inventories.<ref>[https://web.archive.org/web/20091008015109/http://southernstates.com/articles/ca/potash-global.aspx Potash Around the World]. southernstates.com</ref><ref>[http://www.indmin.com/Article/2188737/Channel/0/Potash-global-review-tunnel-vision.html "Potash global review: tunnel vision"] {{Webarchive|url=https://web.archive.org/web/20220331085627/https://www.indmin.com/Article/2188737/Channel/0/Potash-global-review-tunnel-vision.html |date=2022-03-31 }}, ''Industrial Minerals'', May 2009</ref>

The world's largest consumers of potash are China, the United States, Brazil, and India.<ref name="Potassio Do Brasil">[http://www.potassiodobrasil.com.br/index.php/pagina/view/9/supply-demand#x1 Supply and Demand] {{Webarchive|url=https://web.archive.org/web/20101210053902/http://www.potassiodobrasil.com.br/index.php/pagina/view/9/supply-demand#x1 |date=2010-12-10 }}. Potassiodobrasil.com.br. Retrieved on 2013-06-21.</ref>  Brazil imports 90% of the potash it needs.<ref name="Potassio Do Brasil"/> Potash consumption for fertilizers is expected to increase to about 37.8 million tonnes by 2022.<ref name="auto">{{Cite journal|last1=Rawashdeh|first1=Rami Al|last2=Xavier-Oliveira|first2=Emanuel|last3=Maxwell|first3=Philip|date=2016|title=The potash market and its future prospects|journal=Resources Policy|volume=47|pages=154–163|doi=10.1016/j.resourpol.2016.01.011|bibcode=2016RePol..47..154R |issn=0301-4207}}</ref>

Potash imports and exports are often reported in K<sub>2</sub>O ''equivalent'', although fertilizer never contains potassium oxide, per se, because potassium oxide is [[Causticity|caustic]] and [[hygroscopic]].