Publications by authors named "P R Leavitt"
Article Synopsis
- The deoxygenation of freshwater and marine ecosystems is proposed as an important planetary boundary process that influences and is influenced by other planetary boundaries.
- Urgent global monitoring, research, and policy initiatives are necessary to tackle the challenges of rapid deoxygenation, emphasizing the need to include it as a recognized boundary within the planetary boundaries framework.
Article Synopsis
- Eutrophication, driven by nutrient pollution, continues to be a serious issue for inland waters, and its effects on greenhouse gas (GHG) emissions are not well understood.
- A study was conducted to observe how GHG emissions changed in small nitrogen-limited agricultural reservoirs after inducing eutrophication from June to September 2021.
- The results revealed distinct responses from different GHGs: carbon dioxide shifted from a source to a sink, nitrous oxide increased slightly, while methane showed no significant change, indicating that the expected rise in GHG emissions due to agricultural fertilization may not occur uniformly across different ecosystems.
Article Synopsis
- * Salinity significantly affects methane cycling, affecting small water bodies more than larger rivers and lakes, leading to inaccuracies in existing emission estimates.
- * Ignoring salinity in methane emissions calculations could result in an overestimation of up to 81%, highlighting the need to account for salinization in future emissions projections.
Article Synopsis
- Eutrophication affects bacteria by changing nutrient and organic matter processing, but there isn't much research on how bacteria, their diversity, and phytoplankton interactions respond to nutrient management.
- A study compared bacterial communities in a prairie stream upstream and downstream of a wastewater treatment plant before and after a nitrogen removal upgrade, finding shifts in bacterial diversity and composition.
- After the upgrade, which significantly reduced nitrogen levels, some bacterial genera increased while diversity decreased, indicating that effective nutrient removal can improve microbial communities impacted by eutrophication.
Atmospheric warming heats lakes, but the causes of variation among basins are poorly understood. Here, multi-decadal profiles of water temperatures, trophic state, and local climate from 345 temperate lakes are combined with data on lake geomorphology and watershed characteristics to identify controls of the relative rates of temperature change in water (WT) and air (AT) during summer. We show that differences in local climate (AT, wind speed, humidity, irradiance), land cover (forest, urban, agriculture), geomorphology (elevation, area/depth ratio), and water transparency explain >30% of the difference in rate of lake heating compared to that of the atmosphere.
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