Notes on the potential for quantifying carbon sequestration with balloon mapping or other tools

The idea here is to try to quantify carbon sequestered by farming practices, using aerial imagery to do it at large scales. This has been the subject of some discussions on the PLOTS mailing list; the hardest part seems to be developing good measurements of carbon in ground observations on sample sites, and correlating them with remote sensing data. Then the balloon images can be used to generalize and calculate carbon for much larger areas.

Misc notes:

"the earth partners" - estimates of soil carbon

• much of carbon 30cm underground
• poor baseline data

*color change basis from surface imagery, infer underground ones * cover cropping - different color in winter * improving nitrogen use - lowering nitrous oxide emissions * cover cropping for absorbing excess nitrogen * carbon credits - financial reward

Assessing carbon stocks and modelling win-win scenarios of carbon ..., Volume 1 by Raul Ponce-Hernandez, Parviz Koohafkan, Jacques Antoine

The Utility of Remote Sensing Technology in Monitoring Carbon Sequestration Agroforestry Projects - Kim Brown College of Forest Resources, University of Washington, 1996

Factors affecting NDVI: Many researchers believe in an empirical relationship between NDVI and LAI. However, the NDVI:LAI relationship has limits, which should be carefully considered when using values of NDVI as indicators of vegetation biomass. The relationship between NDVI and LAI as measured on the ground is curvilinear, and reaches a plateau at an LAI value of ~6 for coniferous forests (Spanner, Pierce et al. 1990; Spanner, Pierce et al. 1990). [No comparable study has been done in tropical forests.] This could be misleading in monitoring biomass through time. For example, as time passes and temporal images are compared to estimate increase in growth through time, the NDVI may reach a maximum level of 6 but in reality the LAI may be increasing from 6 to 9. This may have particular relevance in considering the task at hand to monitor carbon sequestration in terms of tons.

Relying upon NDVI is based upon the theory that remote biomass measurement a function of chlorophyll (which, as previously explained, NDVI is correlated with). Remote sensing detectors cannot distinguish between fewer leaves with more chlorophyll, and more leaves with less (Baret and Guyot 1991). Leaf display angle is another factor that has been theoretically shown to be confounded with reflectance measurements of LAI (Jacquemoud and Baret 1990). Water stress can also cause decreases in NDVI as it might affect leaf drop and/or chlorophyll reduction which precedes senescence (Peñuelas, Gamon et al. 1994).

Multi-spectral imaging of vegetation for detecting CO2 leaking from underground - Joshua H. Rouse, Joseph A. Shaw, Rick L. Lawrence, Jennifer L. Lewicki, Laura M. Dobeck, Kevin S. Repasky, Lee H. Spangler (for monitoring CO2 stored in underground wells)