About: http://webisa.webdatacommons.org/261963500

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	There are tests for organic forms of nitrogen (that which has been taken up by plants and other organisms), but they are typically more complicated and expensive than tests for the inorganic (available) forms.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com