Answer:
They drained swamps.
Explanation:
The population increase during the Early and Late Classic Periods in Tikal, forced the rulers to find alternatives for high-productive harvests. Intensive methods were introduced that made use of irrigation in Tikal, by means of channels and elevated lands related to hydraulic agriculture that was complemented with gardens of vegetables, fruit trees. Its intensive agriculture, which used the special techniques associated with hydraulic engineering, was also carefully planned, when the entire city was built to collect water in immense deposits, called chultunes, which were silos dug under the subsoil coated with stucco to prevent absorption of water. This was a great feat of Maya engineering, driven by an economic need.
