Everglades peats: using historical and recent data to estimate predrainage and current volumes, masses and carbon contents

Abstract

The Florida Everglades is a patterned peatland formed from sawgrass and other aquatic plant material that has accumulated over millennia. This peatland was initially drained in the late 1800s for agricultural and urban development and has been highly modified by the construction of canals and levées. Restoration plans include providing additional surface water flow which should help to prevent further peat loss by oxidation and encourage the accretion of peat that has been lost through drainage and peat fires. But how much peat has been lost? We know that about 50 % of the original surface area is gone; but what about the driver of ecological processes, the soil? Using Geographic Information Systems (GIS) technology, we compared predrainage and current peat volumes using historical and recent datasets, spatially-referenced soil bulk density values and carbon content to determine peat mass and carbon mass for each Everglades region. Given the uncertainties in the datasets, this analysis should be viewed as providing rough order-of-magnitude values. Our calculations indicate that the current Everglades contains less than 24 % of the original peat volume, 17 % of its mass and 19 % of its carbon.

Keywords

• aquatic plants
• bulk density
• restoration
• sawgrass