Response of soil respiration to changes in soil temperature and water table level in drained and restored peatlands of the southeastern United States
Background: Extensive drainage of peatlands in the southeastern United States coastal plain for the purposes of agriculture and timber harvesting has led to large releases of soil carbon as carbon dioxide (CO2) due to enhanced peat decomposition. Growth in mechanisms that provide fnancial incentives for reducing emissions from land use and land-use change could increase funding for hydrological restoration that reduces peat CO2 emissions from these ecosystems. Measuring soil respiration and physical drivers across a range of site characteristics and land use histories is valuable for understanding how CO2 emissions from peat decomposition may respond to raising water table levels. We combined measurements of total soil respiration, depth to water table from soil surface, and soil temperature from drained and restored peatlands at three locations in eastern North Carolina and one location in southeastern Virginia to investigate relationships among total soil respiration and physical drivers, and to develop models relating total soil respiration to parameters that can be easily measured and monitored in the feld. Results: Total soil respiration increased with deeper water tables and warmer soil temperatures in both drained and hydrologically restored peatlands. Variation in soil respiration was more strongly linked to soil temperature at drained (R2=0.57, p<0.0001) than restored sites (R2=0.28, p<0.0001). Conclusions: The results suggest that drainage amplifes the impact of warming temperatures on peat decomposi tion. Proxy measurements for estimation of CO2 emissions from peat decomposition represent a considerable cost reduction compared to direct soil fux measurements for land managers contemplating the potential climate impact of restoring drained peatland sites. Research can help to increase understanding of factors infuencing variation in soil respiration in addition to physical variables such as depth to water table and soil temperature.
© The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. The Version of Scholarly Record of this Article is published in Carbon Balance and Management, 2022, available online at: https://cbmjournal.biomedcentral.com/articles/10.1186/s13021-022-00219-5 . Keywords: Land-use change; GHG emissions; Pocosin; carbon dioxide; drainage; hydrological restoration; climate change.
Swails, E.E., Ardón, M., Krauss, K.W. et al. Response of soil respiration to changes in soil temperature and water table level in drained and restored peatlands of the southeastern United States. Carbon Balance Manage 17, 18 (2022). https://doi.org/10.1186/s13021-022-00219-5