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Abstract Wildfires may increase soil emissions of trace nitrogen (N) gases like nitric oxide (NO) and nitrous oxide (N2O) by changing soil physicochemical conditions and altering microbial processes like nitrification and denitrification. When 34 studies were synthesized, we found a significant increase in both NO and N2O emissions up to 1 year post-fire across studies spanning ecosystems globally. However, when fluxes were separated by ecosystem type, we found that individual ecosystem types responded uniquely to fire. Forest soils tended to emit more N2O after fire, but there was no significant effect on NO. Shrubland soils showed significant increases in both NO and N2O emissions after fires; often with extremely large but short-lived NO pulses occurring immediately after fire. Grassland NO emissions increased after fire, but the size of this effect was small relative to shrublands. N2O emissions from burned grasslands were highly variable with no significant effect. To better understand the variation in responses to fire across global ecosystems, more consistent measurements of variables recognized as important controls on soil fluxes of NO and N2O (e.g., N cycling rates, soil water content, pH, and substrate availability) are needed across studies. We also suggest that fire-specific elements like burn severity, microbial community succession, and the presence of char be considered by future studies. Our synthesis suggests that fires can exacerbate ecosystem N loss long after they burn, increasing soil emissions of NO and N2O with implications for ecosystem N loss, climate, and regional air quality as wildfires increase globally.
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Accounting for nature's intermittency and growth while mitigating NO 2 emissions by technoecological synergistic design—Application to a chloralkali process
By including ecosystems in process design, it becomes possible to develop synergies between technological and ecological systems to establish islands of environmental sustainability. Such an approach can also ensure that human activities do not degrade ecosystems—the very systems that are essential for our sustainability. This work evaluates the idea of including ecosystems as unit operations in process design [1] while accounting for the intermittency and growth of ecological systems. The technology of selective catalytic reduction (SCR) and a forest ecosystem are both capable of mitigating nitrogen dioxide (NO2) emissions and are designed to support a chloralkali process near Galveston, Texas. The cost of the forest ecosystem taking up NO2is found to be one‐fourth of the cost of the SCR. However, as the capacity of vegetation to take up emissions varies with seasons, the chloralkali process needs to adjust its manufacturing rate accordingly. The result of such adaptation to local ecosystems can be manufacturing with net zero emissions and a step toward environmental sustainability. This study demonstrates the need for further research to address the practical and theoretical aspects of industry and ecosystems to establish mutually beneficial relationships that are economically, ecologically, and societally viable.
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- Award ID(s):
- 1804943
- PAR ID:
- 10461619
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Advanced Manufacturing and Processing
- Volume:
- 1
- Issue:
- 1-2
- ISSN:
- 2637-403X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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