Editing PH (section)

=== pH in soil ===
{{See also|Soil pH}}

[[File:Soil_pH_effect_on_nutrient_availability.svg|thumb|Nutritional elements availability within soil varies with pH. Light blue color represents the ideal range for most plants.]]
The United States Department of Agriculture [[Natural Resources Conservation Service]], formerly Soil Conservation Service classifies [[soil pH]] ranges as follows:<ref>{{cite web |author=Soil Survey Division Staff |title=Soil survey manual.1993. Chapter 3, selected chemical properties. |url=http://soils.usda.gov/technical/manual/contents/chapter3.html |url-status=dead |archive-url=https://web.archive.org/web/20110514151830/http://soils.usda.gov/technical/manual/contents/chapter3.html |archive-date=14 May 2011 |access-date=2011-03-12 |publisher=Soil Conservation Service. U.S. Department of Agriculture Handbook 18}}</ref>
{{Table alignment}}

{| {{table|class=defaultright}}
! scope="col" |Denomination
! scope="col" |pH range
|-
|Ultra acidic
|< 3.5
|-
|Extremely acidic
|3.5–4.4
|-
|Very strongly acidic
|4.5–5.0
|-
|Strongly acidic
|5.1–5.5
|-
|Moderately acidic
|5.6–6.0
|-
|Slightly acidic
|6.1–6.5
|-
|Neutral
|6.6–7.3
|-
|Slightly alkaline
|7.4–7.8
|-
|Moderately alkaline
|7.9–8.4
|-
|Strongly alkaline
|8.5–9.0
|-
|Very strongly alkaline
|9.0–10.5
|-
|Hyper alkaline
|> 10.5
|}
Topsoil pH is influenced by soil parent material, erosional effects, climate and vegetation. A recent map<ref>{{Cite journal |last1=Ballabio |first1=Cristiano |last2=Lugato |first2=Emanuele |last3=Fernández-Ugalde |first3=Oihane |last4=Orgiazzi |first4=Alberto |last5=Jones |first5=Arwyn |last6=Borrelli |first6=Pasquale |last7=Montanarella |first7=Luca |last8=Panagos |first8=Panos |date=2019 |title=Mapping LUCAS topsoil chemical properties at European scale using Gaussian process regression |journal=Geoderma |language=en |volume=355 |pages=113912 |bibcode=2019Geode.35513912B |doi=10.1016/j.geoderma.2019.113912 |pmc=6743211 |pmid=31798185 |doi-access=free}}</ref> of topsoil pH in Europe shows the alkaline soils in Mediterranean, Hungary, East Romania, North France. Scandinavian countries, Portugal, Poland and North Germany have more acid soils.