Soil volume and carbon storage shifts in drained and afforested wetlands of the Paraná River Delta

Authors
Ceballos, Dario Sebastian; Frangi, Jorge L.; Jobbagy Gampel, Esteban Gabriel
Publication Year
2013
Language
English
Format
article
Status
Published version
Description
Wetland ecosystems have a high carbon storage potential as a result of high primary productivity and low decomposition rates dictated by water saturation. In the herbaceous wetlands of the Paraná River Delta, drainage and afforestation with poplars represents one of the dominant land uses. We explored the effects of these interventions on the volume and carbon storage of the young sedimentary soils of the region. At three sites we identified paired stands occupying similar landscape positions and soil types but subject to natural flooding and covered by natural herbaceous communities or drainage and flood control by dikes and covered by poplar plantations established 12, 17 and 19 years ago. Soil sampling at these sites revealed a reduction of the litter compartment (−86 %) and decreasing volume and porosity of its underlying mineral layer (0–10 cm in the wetland reduced to 0–4 cm in the plantation). Our comparisons of carbon storage accounted for these volumetric shifts by using accumulated mineral mass rather than depth as a reference, showing that tree plantations gained in the mineral soil (22 Mg C ha−1) almost as much as what they lost in the litter. These gains were particularly large at intermediate depths (4–43 cm in the plantations) were soil porosity remained unaffected and C was raised by 64 % explained by (1) the pulse of inputs from overlaying litter and organic layers subject to rapid decomposition and mobilization after drainage and (2) root colonization, since tree plantations had 75 % of their fine root biomass at these intermediate soil depths, whereas roots in the wetlands did not explore the mineral soil profile and were completely confined to the organic layer. A neutral C balance following wetland drainage and afforestation resulted from the opposing effects of aeration, favoring decomposition in the organic layer, root colonization and organic matter stabilization, favoring its accumulation in the mineral soil.
EEA Delta del Paraná
Fil: Ceballos, Darío Sebastián. INTA. Estación Experimental Agropecuaria Delta; Argentina
Fil: Frangi, Jorge L. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo-Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigación de Sistemas Ecológicos y Ambientales; Argentina
Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis. Grupo de Estudios Ambientales; Argentina. Universidad Nacional de San Luis; Argentina
Source
Biogeochemistry 112 (1–3) : 359–372 (March 2013)
Subject
Tierras Húmedas
Suelo
Carbono
Compactación del Suelo
Control de Inundaciones
Secuestro de Carbono
Wetlands
Soil
Carbon
Soil Compaction
Flood Control
Carbon Sequestration
Delta del Paraná
Access level
Restricted access
License
Repository
INTA Digital (INTA)
Institution
Instituto Nacional de Tecnología Agropecuaria
OAI Identifier
oai:localhost:20.500.12123/3176