222-3 Assessment of Soil Carbon Stocks Using Remote Sensing Images in a Carbon Rich Ecosystem: the Everglades, Florida, U.S.

See more from this Division: ASA Section: Global Agronomy
See more from this Session: General Global Digital Soil Map (includes Global Digital Soil Map Graduate Student Competition)

Tuesday, November 5, 2013: 10:50 AM
Tampa Convention Center, Room 20

Jongsung Kim, University of Florida, Gainesville, FL, Sabine Grunwald, 2181 McCarty Hall, PO Box 110290, University of Florida, Gainesville, FL and Rosanna G. Rivero, College of Environment and Design, University of Georgia, Athens, GA
Abstract:
Wetland soils play an important role in regulation of the global carbon (C) cycle. Yet it is challenging to accurately evaluate the actual amount of C storages in wetlands. The incorporation of remote sensing (RS) data into digital soil models has great potential to assess C dynamics in wetland soils. Our objectives were to (i) develop C stock prediction models and (ii) assess the amount of C stored in a prominent nutrient-enriched wetland. We collected a total of 108 soil cores at two soil depths (0 – 10 cm and 10 – 20 cm) in a C-rich ecosystem: Water Conservation Area-2A (WCA-2A), Florida, U.S. Random Forest (RF) models to predict soil C stocks were developed using field observation data, environmental ancillary data, and spectral data derived from RS images including SPOT (spatial resolution: 10 m), Landsat ETM+ (30 m), and MODIS (250 m). The RF models showed high performance to predict total C stocks with a R2 between 0.85 to 0.92 and a root mean squared error between 0.75 to 0.86 kg m-2. The variable importance of the RF models showed that hydrology was the major environmental factor controlling the spatial distribution of soil C stocks in WCA-2A. Our results showed that WCA-2A stores about 4.2 mega tons of C in the top 20 cm soils.

See more from this Division: ASA Section: Global Agronomy
See more from this Session: General Global Digital Soil Map (includes Global Digital Soil Map Graduate Student Competition)