The drive was unexpectedly beautiful: a lonely road meandered through the hills, the scenery a juxtaposition of wild growth and arid land.

BBC: A colourful journey into California��s wild interior

Farmers soak up about 85% of the border region's scarce water, and on the semi-arid land on both sides they grow thirsty cash crops like sugar cane.

ECONOMIST: IOU H2O

It is an arid, lonesome land, cut only by the blue scalpel line of the Rio Grande.

ECONOMIST: The Mexican border

Biomes such as river, estuary (the mouth of the Limary River), coastline, semi-arid sclerophyll shrub land and evergreen relict forest are represented.

UNESCO: EDUCATION

"But I could only teach them this, " he says, pointing to the arid cornfields on his small parcel of land.

BBC: Mexico seeks 'end of world' Maya tourism boost

Drylands, which range from "dry sub-humid" to "hyper-arid" regions, make up more than 40 percent of the world's land surface and are home to two billion people.

CNN: Growing deserts 'a global problem'