Good flooding? Scientists use rice cultivation to guard soil in Florida's Everglades Agricultural Area

Nearly 25,000 acres (10,000 hectares) of rice are grown in Florida each summer. Agricultural area of ​​the Evergladesan area of ​​roughly 2,800 square kilometers south of Lake Okeechobee.

Farming here requires an important deal of sensitivity. The area has lost almost 1.8 metres of soil within the last century on account of Process called soil subsidence.

One option to slow this subsidence and preserve the nutrient-rich soil is to flood the world during Florida's rainy season and use the fields to grow rice. The fields are flooded with water from the adjoining canals. Once the water dries up or seeps away, the rice is harvested.

The Conversation asked Associate Professor Jehangir Bhadha, a Soil sustainability expert on the University of Florida, how the university got here to grow rice and what advantages this brings to the environment.

What is the story behind rice cultivation within the Everglades?

In the Fifties, rice was grown for a short while within the Everglades Agricultural Area, but the world was limited to about 2,000 acres (800 hectares).

Then got here the invention of a rice virus in Florida called Hoja Blanca or white leafwhich causes the plants to wither and even kill them. This virus was first discovered within the late Fifties in Colombia and Venezuela.

Rice made a comeback in Florida in 1977 after farmers within the Everglades Agricultural Area demonstrated that it grown on sugar cane fields in the course of the summer fallow period from May to August – when it is simply too hot and wet to grow vegetables in South Florida. By this time, Hoja Blanca disease was under control and recent resistant rice varieties were being developed.

In late spring and summer, greater than 20,000 hectares of fallow sugarcane land within the Everglades Agricultural Area can be found for rice cultivation. In 2023 About half of this area was planted with rice.The remaining land is either left fallow or flooded but doesn’t produce rice – a practice commonly known as “Fallow water flooding.”

On average, every hectare cultivated yields approx. 2 tons (1,800 kilograms) of rice.

What makes rice cultivation on this area so special?

Rice cultivation within the Everglades Agricultural Area doesn’t require initial fertilization with nitrogen, phosphorus or potassium since the region's soils are highly organic and nutrient-rich.

The area covers almost 450,000 acres (180,000 hectares) organic soils generally known as histosols. These soils contain as much as 80% organic matter, making them unique to the region and a vital resource for its thriving agriculture. Histosols are sometimes called bathroom or peat soils.

The Histosols of South Florida were formed over a period of several thousand years as organic material gathered faster than it could decompose within the flooded sawgrass prairies that flourished in the world south of Lake Okeechobee.

But for the reason that land here was drained for agriculture within the early twentieth century, organic material has been decomposing faster than it may possibly grow back. This is especially on account of microbially mediated oxidation, which occurs when organic material is slowly decomposed and consumed by microbes, resulting in a gradual lack of soil and a lowering of surface elevation.

The soil depth on this area varies from just a few centimeters to as much as 1.5 meters. Beneath the Histosols lies hard limestone rock that just isn’t suitable for agriculture. In many places the limestone rock is exposed on the surface or parts of it are incorporated into the soil.

What contribution does rice cultivation make to soil health there?

By flooding the fields for long periods of time, farmers suppress each the microbial activity that results in oxidation and the hatching of Pests. It also increases the water holding capability of the soilwhich allows for higher moisture retention within the drier seasons.

The improved soil health advantages the sugar cane crop and maximizes the lifespan of the soil.

The cultivation of flooded rice has also proven to be Attracting waders How great white heron, Great Egret And Glossy-headed Ibis.

What work is your team currently doing?

In the last 15 years, more rice and more varieties of rice have been grown. While in 2008 only two dominant varieties were grown on around 4,800 hectares, by 2023 there have been already greater than 10 varieties on 9,300 hectares.

To ensure a continuous supply of latest varieties, researchers and others University of Florida Institute of Food and Agricultural Sciencesalong with Company: Florida Rice Growers Inc.conduct annual rice variety trials to guage recent or existing varieties in South Florida. The goal of the trials is to discover high-yielding, disease-resistant rice varieties which might be compatible with the region's subtropical climate and highly organic soils.

Every summer University of Florida IFAS Extension and the Research Faculty hold a rice field day dedicated to presenting their current research.