In 1502, Columbo and Bartrolomeo encountered Maya traders. The Classic Period Maya were indeed a trading society. Each geographic location exported goods unique to its environment and geological resources. Those of the lowlands traded tobacco, honey, pottery, skins, vegetable dyes and rubber. In the highlands, they exported jade, obsidian, cinnabar and quetzal feathers. Coastal dwellers specialized in salt, pearls, shells and dried fish.

Like the Olmec before them, the Classic Maya were also accomplished farmers. Challenged by a thin layer of topsoil that would be nutrient deplete after just two years of cultivation, they developed a slash-and-burn farming method. Aerial photography of higher elevations shows the remains of terraced farmlands. In the lowlands, the Maya created gridlike networks of drainage canals. Conquistador Diaz del Castillo would later say this same canal system was used for inland canoe travel. Farms and cities were situated near local dzonot or cenotes; natural rainwater filled reservoir pools created by the collapse of cave ceilings

The main agricultural focus was maize, but farmers also grew kidney beans, sweet potatoes, squash, cacao, avocados, tomatoes, peppers, guavas, melons, and cotton. Cacao in particular was highly valued, the beans of which were used as currency. In addition to farming, the Classic Maya raised stingless bees and collected their honey, but only three domestic animals were known to them; acehpek (dogs), turkeys, and javelina (peccary). With blowguns, spears, bows/arrows and darts, they would hunt deer, armadillo, monkey, iguana and quail as game. Their seafood diet staples included salt water fish, turtles, and oysters. But the increasing population eventually strained their natural protein supply. Studies have shown that as time passed, the rate of malnutrition amongst Maya steadily progressed.

~from Zama Roca's TULUM
http://www.quia.com/files/quia/users/titian1/member/Zama/TulumSplash.htm