2.4 Objective 2

Identify region-specific correlations between aboveground and belowground organic carbon stocks in mangroves

Hypothesis: After controlling for site-specific effects, mangrove species composition and forest structure will act as key predictors of belowground soil organic carbon stocks across regions

Rationale: Several predictive models of aboveground and belowground carbon stocks in mangroves have emerged within the last five years. The prior work that informs this chapter developed a site-specific predictive model of ecosystem carbon stocks for mangroves of the Indo-West Pacific (IWP) region. This modeling effort was implemented under the premise that global models may lose accuracy at small scales, yet small expanses of mangroves are still ecologically and socioeconomically relevant for conservation. Following external interest in parameterization of the model for regions outside of the IWP, the proposed chapter will repeat the study in the remaining regions of the world where mangroves predominate. The study will allow for cross regional comparisons of correlations found between forest structure and belowground soil organic carbon (SOC) density, which were found to be significant after controlling for site-specific effects in the IWP.

Methods: Building upon the database compiled for the IWP, I will compile plot-level data of forest structure as well as species composition and soil conditions from the published literature. All data will be georeferenced by country, site, and plot, which will allow for investigation of spatial patterning and correlations in aboveground and belowground carbon stocks at multiple spatial scales. Compilation of the database will facilitate additional efforts, such as refining estimates of carbon stocks and losses at the national or regional levels. The study will be a valuable exercise in research reproducibility, and will also provide a fundamental database of in situ measurements of forest structure, species assemblage, and soil conditions that may be employed in other studies.