Enhanced benthic nitrous oxide and ammonium production after natural oxygenation of long‐term anoxic sediments

Twenty-one U.S. Navy divers were given several standard visual tests, the Purdue Peg-board, the Bennett Hand Tool Dexterity Test, and the Wechsler Memory Scale while breathing air or 30% nitrous oxide. The results showed that visual function, fine and gross motor performance, and long-term memory were normal under nitrous oxide, while learning and short-term memory were significantly impaired. The subjective effects of breathing nitrous oxide were similar to those experienced during compressed air narcosis. The selective impairment of short-term memory suggests that divers might be able to perform useful work at depths deeper than those currently authorized, provided the tasks were well learned and practiced.

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Anesthesia With and Without Nitrous Oxide and Long-term Cognitive Trajectories in Older Adults

Anesthesia & Analgesia ◽

10.1213/ane.0000000000004490 ◽

2019 ◽

Vol 131 (2) ◽

pp. 594-604

Author(s):

Juraj Sprung ◽

Arnoley S. (Arney) Abcejo ◽

David S. Knopman ◽

Ronald C. Petersen ◽

Michelle M. Mielke ◽

...

Keyword(s):

Older Adults ◽

Nitrous Oxide

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Long-term nutrient addition increases respiration and nitrous oxide emissions in a New England salt marsh

Ecology and Evolution ◽

10.1002/ece3.3955 ◽

2018 ◽

Vol 8 (10) ◽

pp. 4958-4966 ◽

Cited By ~ 8

Author(s):

Rose M. Martin ◽

Cathleen Wigand ◽

Elizabeth Elmstrom ◽

Javier Lloret ◽

Ivan Valiela

Keyword(s):

Nitrous Oxide ◽

Salt Marsh ◽

New England ◽

Nutrient Addition ◽

Nitrous Oxide Emissions ◽

England Salt Marsh

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High nitrous oxide fluxes from rice indicate the need to manage water for both long- and short-term climate impacts

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1809276115 ◽

2018 ◽

Vol 115 (39) ◽

pp. 9720-9725 ◽

Cited By ~ 35

Author(s):

Kritee Kritee ◽

Drishya Nair ◽

Daniel Zavala-Araiza ◽

Jeremy Proville ◽

Joseph Rudek ◽

...

Keyword(s):

Nitrous Oxide ◽

Greenhouse Gas ◽

Indian Subcontinent ◽

Inorganic Nitrogen ◽

Climate Impacts ◽

Rice Cultivation ◽

Farming Practices ◽

Short Term ◽

Continuous Flooding

Global rice cultivation is estimated to account for 2.5% of current anthropogenic warming because of emissions of methane (CH4), a short-lived greenhouse gas. This estimate assumes a widespread prevalence of continuous flooding of most rice fields and hence does not include emissions of nitrous oxide (N2O), a long-lived greenhouse gas. Based on the belief that minimizing CH4 from rice cultivation is always climate beneficial, current mitigation policies promote increased use of intermittent flooding. However, results from five intermittently flooded rice farms across three agroecological regions in India indicate that N2O emissions per hectare can be three times higher (33 kg-N2O⋅ha−1⋅season−1) than the maximum previously reported. Correlations between N2O emissions and management parameters suggest that N2O emissions from rice across the Indian subcontinent might be 30–45 times higher under intensified use of intermittent flooding than under continuous flooding. Our data further indicate that comanagement of water with inorganic nitrogen and/or organic matter inputs can decrease climate impacts caused by greenhouse gas emissions up to 90% and nitrogen management might not be central to N2O reduction. An understanding of climate benefits/drawbacks over time of different flooding regimes because of differences in N2O and CH4 emissions can help select the most climate-friendly water management regimes for a given area. Region-specific studies of rice farming practices that map flooding regimes and measure effects of multiple comanaged variables on N2O and CH4 emissions are necessary to determine and minimize the climate impacts of rice cultivation over both the short term and long term.

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