MEXICO CITY (AP) — Cassandra Garduño squinted in the sunlight, her pink boots smudged by dirt as she gazed out over her family’s chinampa — one of the islands first built up by the Aztecs with fertile mud from the bottom of a lake that, later drained, would one day become Mexico City. Food from these islands has fed people for hundreds of years, but the chinampas are under threat from urbanization. The produce grown here doesn’t fetch much money, and many families are abandoning the ancient practice to rent out or sell their land for more lucrative uses such as soccer fields.

“People don’t want to farm anymore,” said Garduño. “They don’t see it as a necessity, they don’t want to produce, and people don’t want to buy the products.” Some of those remaining, like Garduño, are banding together to preserve and promote the traditional use of the chinampas.

“None of this can exist without human hands, the hands of those who worked here and created the chinampa a thousand years ago,” she said on a recent morning as the smell of celery growing nearby filled the air. The gardens crisscrossed by canals in the capital’s southern Xochimilco borough are built up from layers of dredged soil, held together by tall, thin ahuejotes — a kind of willow tree — planted around their perimeter. Xochimilco has more than 2,500 acres of protected land owned by generations of local chinamperos, as those who farm the islands are known.

Garduño’s earliest memori.