Increased carbon capture by a silicate-treated forested watershed affected by acid deposition
oleh: L. L. Taylor, C. T. Driscoll, P. M. Groffman, P. M. Groffman, G. H. Rau, J. D. Blum, D. J. Beerling
| Format: | Article |
|---|---|
| Diterbitkan: | Copernicus Publications 2021-01-01 |
Deskripsi
<p>Meeting internationally agreed-upon climate targets requires carbon dioxide removal (CDR) strategies coupled with an urgent phase-down of fossil fuel emissions. However, the efficacy and wider impacts of CDR are poorly understood. Enhanced rock weathering (ERW) is a land-based CDR strategy requiring large-scale field trials. Here we show that a low 3.44 t ha<span class="inline-formula"><sup>−1</sup></span> wollastonite treatment in an 11.8 ha acid-rain-impacted forested watershed in New Hampshire, USA, led to cumulative carbon capture by carbonic acid weathering of 0.025–0.13 t CO<span class="inline-formula"><sub>2</sub></span> ha<span class="inline-formula"><sup>−1</sup></span> over 15 years. Despite a 0.8–2.4 t CO<span class="inline-formula"><sub>2</sub></span> ha<span class="inline-formula"><sup>−1</sup></span> logistical carbon penalty from mining, grinding, transportation, and spreading, by 2015 weathering together with increased forest productivity led to net CDR of 8.5–11.5 t CO<span class="inline-formula"><sub>2</sub></span> ha<span class="inline-formula"><sup>−1</sup></span>. Our results demonstrate that ERW may be an effective, scalable CDR strategy for acid-impacted forests but at large scales requires sustainable sources of silicate rock dust.</p>