Towards up-scaling restored wetland CO2 and CH4 exchange in the Sacramento - San Joaquin River Delta
Abstract
Returning agricultural land to wetlands in the Sacramento - San Joaquin River Delta of northern California (hereafter, the Delta) can help reverse the land subsidence that is currently threatening a large proportion of California's water supply. Wetland restoration maintains plant productivity while drastically reducing the rapid peat decomposition that has occurred since this region was drained for agricultural use in the 1850s. Rebuilding the peat soils i) protects California's water supply by reducing pressure on levies, and ii) mitigates globally rising atmospheric CO2 concentrations. The more anaerobic soil environment of wetlands, however, promotes methane (CH4) production, a 25x more potent greenhouse gas than CO2. It is therefore important to understand the impact of wetland restoration on both these gases to evaluate both subsidence reversal and climate change mitigation goals. To this end, we are conducting eddy covariance measurements of gas exchange in restored Delta wetlands to quantify ecosystem-scale sequestration/emission of CO2 and CH4. The ultimate goal of these measurements is to be able to predict the effects of wetland restoration on Delta-wide fluxes of these important greenhouse gases. Wetlands, however, are spatially variable ecosystems, varying in substrate, plant species, plant density, and open water fraction, to name a few. Extending site-level measurements to other areas therefore requires attributing spatial variability in CO2 and CH4 exchange to respective sources and identifying spatially available indicators of this change. This poster presents preliminary results evaluating the spatial variability of CO2 and CH4 fluxes in two restored Delta wetlands and how this variability can be up-scaled to region-wide estimates using remotely sensed indicators.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFM.B33A0462S
- Keywords:
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- 0497 BIOGEOSCIENCES Wetlands;
- 0428 BIOGEOSCIENCES Carbon cycling;
- 0426 BIOGEOSCIENCES Biosphere/atmosphere interactions;
- 0480 BIOGEOSCIENCES Remote sensing