Dynamics of CO<sub>2</sub> and CH<sub>4</sub> fluxes in Red Sea mangrove soils
<p>Red Sea mangroves have a lower carbon burial rate than the global average, whereby small greenhouse gas fluxes may offset a large proportion of carbon burial. Monthly soil core sampling was conducted across 2 years at two sites within a central eastern Red Sea mangrove stand to examine carb...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2025-01-01
|
| Series: | Biogeosciences |
| Online Access: | https://bg.copernicus.org/articles/22/117/2025/bg-22-117-2025.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | <p>Red Sea mangroves have a lower carbon burial rate than the global average, whereby small greenhouse gas fluxes may offset a large proportion of carbon burial. Monthly soil core sampling was conducted across 2 years at two sites within a central eastern Red Sea mangrove stand to examine carbon dioxide (CO<span class="inline-formula"><sub>2</sub></span>) and methane (CH<span class="inline-formula"><sub>4</sub></span>) fluxes under dry and inundated conditions. Fluxes were highly variable, characterized by a prevalence of low emissions punctuated by bursts of high emissions. At the landward site, average <span class="inline-formula">±</span> SE (median) flux from the soil–air interface was 3111 <span class="inline-formula">±</span> 929 (811) <span class="inline-formula">µ</span>mol CO<span class="inline-formula"><sub>2</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> and 1.68 <span class="inline-formula">±</span> 0.63 (0.26) <span class="inline-formula">µ</span>mol CH<span class="inline-formula"><sub>4</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> under light conditions and 8657 <span class="inline-formula">±</span> 2269 (1615) <span class="inline-formula">µ</span>mol CO<span class="inline-formula"><sub>2</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> and 0.84 <span class="inline-formula">±</span> 0.79 (0.59) <span class="inline-formula">µ</span>mol CH<span class="inline-formula"><sub>4</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> under dark conditions. Average <span class="inline-formula">±</span> SE (median) sea–air fluxes were <span class="inline-formula">−</span>55 <span class="inline-formula">±</span> 165 (<span class="inline-formula">−</span>79) <span class="inline-formula">µ</span>mol CO<span class="inline-formula"><sub>2</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> and 0.12 <span class="inline-formula">±</span> 0.23 (0.08) <span class="inline-formula">µ</span>mol CH<span class="inline-formula"><sub>4</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> under light conditions and 27 <span class="inline-formula">±</span> 48 (53) <span class="inline-formula">µ</span>mol CO<span class="inline-formula"><sub>2</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> and 0.16 <span class="inline-formula">±</span> 0.13 (0.09) <span class="inline-formula">µ</span>mol CH<span class="inline-formula"><sub>4</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> in dark conditions. The seaward site recorded a higher CH<span class="inline-formula"><sub>4</sub></span> flux, averaging 18.7 <span class="inline-formula">±</span> 8.18 (1.7) and 17.1 <span class="inline-formula">±</span> 4.55 (7.7) <span class="inline-formula">µ</span>mol CH<span class="inline-formula"><sub>4</sub></span> m<span class="inline-formula"><sup>−2</sup></span> d<span class="inline-formula"><sup>−1</sup></span> in light and dark conditions. Mean fluxes offset 94.5 % of carbon burial, with a median of 4.9 % skewed by extreme variability. However, reported CO<span class="inline-formula"><sub>2</sub></span> removal by total alkalinity emission from carbonate dissolution greatly exceeded both processes and drives the role of these ecosystems as intense CO<span class="inline-formula"><sub>2</sub></span> sinks.</p> |
|---|---|
| ISSN: | 1726-4170 1726-4189 |