ethanol is a kind of resource & as the use of a resource increases, the use of materials that resource is made out of increases ->  as the use of ethanol increases, the use of materials that ethanol is made out of increases  as the use of ethanol increases, the use of materials that ethanol is made out of increases & ethanol sometimes is made of corn ->  as the use of ethanol increases, the use of corn increases  as the use of ethanol increases, the use of corn increases & if the use of something increases then more of that something will have to be produced ->  as the use of ethanol increase, more corn will have to be produced  corn is a kind of crop & producing crops requires using farm land ->  producing corn requires using farm land  as the use of ethanol increase, more corn will have to be produced & producing corn requires using farm land ->  as the use of ethanol increases, more farm land will be used  if something becomes less available then the amount of that something that is available decreases & if more farm land is used then less farm land will be available ->  if more farm land is used then the amount of available farm land will decrease  as the use of ethanol increases, more farm land will be used & if more farm land is used then the amount of available farm land will decrease ->  as the use of ethanol increases, the amount of available farm land will decrease  a farmer farms crops / plants for food & producing crops requires using farm land ->  producing food requires using farm land  as the use of ethanol increases, the amount of available farm land will decrease & producing food requires using farm land -> as the use of ethanol increases, the amount of available farm land for food production decreases