Global-Change Controls on Soil-Carbon Accumulation and Loss in Coastal Vegetated Ecosystems

Journal Article Resource
March 2021

Parallel grid ditches were dug in approximately 90% of mid-Atlantic and New England salt marshes in the 1920s through the 1940s. Today, managers must navigate the effects of past actions when making decisions about marsh hydrology and drainage that impact human health, ecosystem services, and marsh sustainability. Managers must also consider how stressors such as sea level rise impact marshes. A collaborative research project helped to address this challenge by working iteratively with end user groups to develop a decision support tool for marsh hydrology management strategies that promote sustainability and delivery of valuable ecosystem services under future sea level scenarios.

About this article

This 2019 article, which appeared in Nature Geoscience, suggests the importance of the integration of decomposition mechanisms into blue carbon models for predicting soil organic carbon stores. These findings were generated as part of a 2017-2020 collaborative research project.

Abstract

Coastal seagrass, mangrove and salt-marsh ecosystems—also termed blue-carbon ecosystems—play an important role in the global carbon cycle. Much of the organic carbon they store rests in soils that have accumulated over thousands of years. Rapidly changing climate and environmental conditions, including sea-level rise, warming, eutrophication and landscape development, will impact decomposition and thus the global reservoir of blue soil organic carbon. Yet, it remains unclear how these disturbances will affect the key biogeochemical mechanisms controlling decomposition—mineral protection, redox zonation, water content and movement, and plant–microbe interactions. We assess the spatial and temporal scales over which decomposition mechanisms operate and how their effectiveness may change following disturbances. We suggest that better integration of decomposition mechanisms into blue-carbon models may improve predictions of soil organic carbon stores and facilitate incorporation of coastal vegetated ecosystems into global budgets and management tools.

Citation: 

Spivak, A.C., Sanderman, J., Bowen, J.L. et al. Global-change controls on soil-carbon accumulation and loss in coastal vegetated ecosystems. Nature Geoscience. 12, 685–692 (2019). https://doi.org/10.1038/s41561-019-0435-2