<http://webisa.webdatacommons.org/prov/193823169>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/78576999> .
<http://webisa.webdatacommons.org/78576999>	<http://www.w3.org/ns/prov#value>	"Especially in the drylands, where demand chronically outstrips renewable supply, management is a challenge." .
<http://webisa.webdatacommons.org/78576999>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/78576999>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<columbia.edu> .