- Proceedings of the National Academy of Sciences of the United States of America
- Published about 4 years ago
Ground-level ozone is adverse to human and vegetation health. High ground-level ozone concentrations usually occur over the United States in the summer, often referred to as the ozone season. However, observed monthly mean ozone concentrations in the southeastern United States were higher in October than July in 2010. The October ozone average in 2010 reached that of July in the past three decades (1980-2010). Our analysis shows that this extreme October ozone in 2010 over the Southeast is due in part to a dry and warm weather condition, which enhances photochemical production, air stagnation, and fire emissions. Observational evidence and modeling analysis also indicate that another significant contributor is enhanced emissions of biogenic isoprene, a major ozone precursor, from water-stressed plants under a dry and warm condition. The latter finding is corroborated by recent laboratory and field studies. This climate-induced biogenic control also explains the puzzling fact that the two extremes of high October ozone both occurred in the 2000s when anthropogenic emissions were lower than the 1980s and 1990s, in contrast to the observed decreasing trend of July ozone in the region. The occurrences of a drying and warming fall, projected by climate models, will likely lead to more active photochemistry, enhanced biogenic isoprene and fire emissions, an extension of the ozone season from summer to fall, and an increase of secondary organic aerosols in the Southeast, posing challenges to regional air quality management.
Rather than exploring how indigenous people have been alienated from resources by environmental policies, this paper explores how indigenous peoples have worked with environmental organizations to use the broad protections provided by environmental laws to protect cultural resources. The Eastern Band of Cherokee Indians, along with other concerned groups, partnered with environmentalists in opposing the destruction of the endangered snail darter’s critical habitat by the Tennessee Valley Authority’s Tellico Dam. The dam had been opposed by a shifting alliance of Cherokees, local farmers, trout fisherman, and environmentalists since it was announced in 1963. A previous lawsuit by this coalition delayed the project from 1972 to 1974 under the National Environmental Policy Act. The Endangered Species Act provided this coalition with a powerful tool for opposing the destruction of burial grounds and sacred village sites throughout the lower Little Tennessee River valley. The coalition of environmental organizations, Cherokees, and others was ultimately unsuccessful in stopping the dam from being built, but was successful in establishing a strict precedent for the enforcement of the Endangered Species Act. The lawsuit also created a space for the Eastern Band to negotiate for the return of Cherokee remains and halt the removal of any additional burials. In this situation, the strategic support of environmental regulation enabled the Eastern Band to exert some degree of control over the fate of cultural resources in the valley, and also demonstrates the significant role American Indian peoples played in one of the seminal events of the environmental movement during the 1970s.
Mercury stable isotope abundances were used to trace transport of Hg-impacted river sediment near a coal ash spill at Harriman, Tennessee, USA. δ202Hg values for Kingston coal ash released into the Emory River in 2008 are significantly negative (-1.78±0.35‰), whereas sediments of the Clinch River, into which the Emory River flows, are contaminated by an additional Hg source (potentially from Y-12 complex near Oak Ridge, Tennessee) with near-zero values (-0.23±0.16‰). Nominally uncontaminated Emory River sediments (12 miles upstream from the confluence with the Clinch) have intermediate values (-1.17±0.13‰) and contain lower Hg concentrations. Emory River mile 10 sediments, possibly impacted by an old paper mill (δ202Hg values of -0.47±0.04‰). A mixing model, using δ202Hg values and Hg concentrations, yielded estimates of the relative contributions of coal ash, Clinch River, and Emory River sediments for a suite of 71 sediment samples taken over a 30 month time period from 13 locations. Emory River samples, with two exceptions, are unaffected by Clinch River sediment, despite occasional upstream flow from the Clinch River. As expected, Clinch River sediment below its confluence with the Emory River are affected by Kingston coal ash; however, the relative contribution of the coal ash varies among sampling sites.
Smoke-free air laws in restaurants and bars protect patrons and workers from involuntary exposure to secondhand smoke, but owners often express concern that such laws will harm their businesses. The primary objective of this study was to estimate the association between local smoke-free air laws and economic outcomes in restaurants and bars in 8 states without statewide smoke-free air laws: Alabama, Indiana, Kentucky, Mississippi, Missouri, South Carolina, Texas, and West Virginia. A secondary objective was to examine the economic impact of a 2010 statewide smoke-free restaurant and bar law in North Carolina.
To characterize treatment patterns and outcomes in eyes with treatment-naïve myopic choroidal neovascularization (mCNV) in the United States.
To evaluate the effectiveness of a multilevel intervention designed to prevent underage alcohol use among youths living in the Cherokee Nation.
A long-term assumption in ecology is that species distributions correspond with their niche requirements, but evidence that species can persist in unsuitable habitat for centuries undermines the link between species and habitat. Moreover, species may be more dependent on mutualist partners than specific habitats. Most evidence connecting indigenous cultures with plant dispersal is anecdotal, but historical records suggest that Native Americans transported and cultivated many species, including Gleditsia triacanthos (“Honey locust”). Gleditsia triacanthos was an important medicinal/culinary (e.g., sugar), cultural (e.g., game sticks) and spiritual tree for the Cherokee (southeastern U.S. Native Americans). This study tests the hypothesis that a Cherokee cultivation legacy drives current regional G. triacanthos distribution patterns. Gleditsia triacanthos occurs in rocky uplands and xeric fields, but inexplicably also occurs in mesic riverine corridors and floodplains where Cherokee once settled and farmed. I combined field experiments and surveys in the Southern Appalachian Mountain region (U.S.) to investigate G. triacanthos recruitment requirements and distribution patterns to determine whether there is a quantifiable G. triacanthos association with former Cherokee settlements. Moreover, I also investigated alternate dispersal mechanisms, such as stream transport and domestic cattle. The results indicate that a centuries-old legacy of Native American cultivation remains intact as G. triacanthos' current southern Appalachian distribution appears better explained Cherokee settlement patterns than habitat. The data indicate that the tree is severely dispersal limited in the region, only moving appreciable distances from former Cherokee settlements where cattle grazing is prevalent. Human land use legacy may play a long-term role in shaping species distributions, and pre-European settlement activity appears underrated as a factor influencing modern tree species distributions.
Since its discovery in 2009, the tickborne Heartland virus (HRTV) has caused human illness in Missouri, Oklahoma, and Tennessee USA. To better assess the geographic distribution of HRTV, we used wildlife serology as an indicator. This retrospective evaluation determined that HRTV is widespread within the central and eastern United States.
Approximately 8,500 vape shops in the United States sell a variety of electronic nicotine delivery systems (ENDS). This study examined vape shop operators' perceptions of benefits and risk of ENDS use, what they perceive to be the reasons for ENDS use, their source of product information, what information they shared with customers, and the impact of existing and future regulation of ENDS on its use and on their business.
- Clinical journal of the American Society of Nephrology : CJASN
- Published almost 5 years ago
The prevalence of nephrolithiasis in the United States has increased substantially, but recent changes in incidence with respect to age, sex, and race are not well characterized. This study examined temporal trends in the annual incidence and cumulative risk of nephrolithiasis among children and adults living in South Carolina over a 16-year period.