From 800 BC to 200 AD, a vast wetland-based agroecosystem was managed in southeastern Mexico using canals, raised beds (platforms), and other water management structures that occupied nearly 20,000 hectares. These structures evidence several strategies used by prehispanic Maya of the Yucatan Peninsula to cultivate in conditions of excess water, caused by annual precipitation averaging 2,000 mm of which 76% occurs between May and October. By analyzing the remains of these canal and platform systems, scientists have deduced strategies for their use. Mayans excavated canals down to the bottom of the topsoil layers and formed platforms by mounding the removed soil to create planting surfaces between the canals. Soils eroded from platforms included organic materials that slowly filled canals. It is not known exactly what types of crops were planted in this system due to quick plant decomposition in the tropics, but work in other regions suggests maize and cotton were important crops. 

Many agroecosystems are situated in wetlands or regions that are periodically flooded during a wet season. Management of these wetland systems requires limiting water in times of inundation and extending the cropping season in times of draught. Much can be learned from prehistoric wetland based agroecosystem management and the current indigenous farming techniques in wetland areas of Mexico that were most likely handed down from Mayan ancestors. Periodic cleaning of canals returns rich soils to the planting platforms, and soil studies demonstrate that nitrogen levels were highest on the platforms and dropped off rapidly with increased depth. Maize yields are over four times greater in these traditional indigenous farming systems compared to adjacent fields that have been cleared, drained and farmed using modern techniques. 

Use Renewable Resources

Crop and non-crop residues are left on the soil surface and recycled as fertilizer for the following crop.

Conserve Resources

Efficient irrigation systems conserve water, enabling Mayans and their ancestors in wetland regions to produce food where otherwise impossible. Use of local varieties of seeds conserves genetic resources.

Manage Ecological Relationships

Soil nutrients are recycled from canal bottoms and returned to the raised platforms. After harvest, maize stalks are left on the soil to recycle nutrients and organic materials.

Adjust to Local Environments

Strategies such as raised beds and canals adapt farming systems to the physical limitations of the farm landscape.

Empower People

Farmers in lowland regions of Mexico use indigenous knowledge handed down from generation to generation.

Manage Whole Systems

By harvesting and recycling sediments, aquatic systems are kept clear of sediment accretion while maintaining fertility of raised beds, managing nutrients across entire landscapes.

Maximize Long-Term Benefits

Raised bed and canal systems have proven to be long-term strategies of farming, sustaining productivity under continuous use for more than 1000 years. 

A soil profile through a raised bed