632 research outputs found
The evolution of a coastal carbon store over the last millennium
This work was financially supported by the Natural Environment Research Council (grant number: NE/L501852/1), the EU FPV HOLSMEER project (EVK2-CT-2000-00060) and the EU FPVI Millennium project (contract number 017008), Biotechnology and Biological Sciences Research Council (grant number: BB/M026620/1) with additional support from the NERC Radiocarbon Facility (Allocation 1154.1005 and 2195.1019).Fjord sediments are recognized as hotspots for the burial and storage of organic carbon, yet little is known about the long-term drivers of significant terrestrial organic carbon (OC) transfers into these coastal carbon stores. The mid-latitude fjord catchments of Scotland have a long history of human occupation and environmental disturbance. We provide new evidence to show that increased anthropogenic disturbances over the last 500 years appear to have driven a step change in the magnitude of terrestrial OC transported to the coastal ocean. Increased pressures from mining, agriculture and forestry over the latter half of the last millennium have destabilized catchment soils and remobilized deep stores of aged OC from the catchment to the coastal ocean. Here we show that fjord sediments are capable of acting as highly responsive and effective terrestrial OC sinks, with OC accumulation rates increasing up to 20 % during the peak period of anthropogenic disturbance. The responsiveness and magnitude of the fjord OC sink represents a potentially significant time-evolving component of the global carbon cycle that is currently not recognized but has the potential to become increasingly important in the understanding of the role of these coastal carbon stores in our climate system.PostprintPeer reviewe
Impacts of Water Development on Great Salt Lake and the Wasatch Front
Although droughts and floods produce shortāterm fluctuations in the elevation of Great Salt Lake, water diversions since the arrival of 19th Century pioneers represent a persistent reduction in water supply to the lake, decreasing its elevation by 11 feet and exposing much of the lake bed. As Utah moves forward, we need to be aware of the impacts of lowered lake levels and make decisions that serve the interests of all Utahns. In particular, proposals to further develop the water supply of the Great Salt Lake should carefully consider potential impacts to the health of the lake and examine the tradeoffs. There are no water rights to protect Great Salt Lake, so water development currently focuses solely on whether there is water upstream to divert. If future water projects reduce the supply of water to the lake, its level will continue to drop.1 Although water conservation has reduced urban per capita use by 18 percent, overall municipal water use has increased by 5 percent because of our growing population.2 To significantly reduce water use, a balanced conservation ethic needs to consider all uses, including agriculture, which consumes 63 percent of the water in the Great Salt Lake Basin.
Increased awareness of how water use is lowering Great Salt Lake will help us avoid the fate of other salt lakes such as the Aral Sea in Central Asia or Californiaās Owens Lake, both of which have been desiccated and now cause severe environmental problems. We must look beyond the next few decades and decide how we value the lake for future generations. Lower lake levels will increase dust pollution and related human health impacts, and reduce industrial and environmental function of Great Salt Lake. We must be willing to make decisions now that preserve Great Salt Lakeās benefits and mitigate its negative impacts into the coming centuries
Rodent-Mediated Interactions Among Seed Species of Differing Quality in a Shrubsteppe Ecosystem
Interactions among seeds, mediated by granivorous rodents, are likely to play a strong role in shrubsteppe ecosystem restoration. Past studies typically consider only pairwise interactions between preferred and less preferred seed species, whereas rangeland seedings are likely to contain more than 2 seed species, potentially leading to complex interactions. We examined how the relative proportion of seeds in a 3-species polyculture changes rodent seed selectivity (i.e., removal) and indirect interactions among seeds. We presented 2 rodent species, Peromyscus maniculatus (deer mice) andPerognathus parvus (pocket mice), in arenas with 3-species seed mixtures that varied in the proportion of a highly preferred, moderately preferred, and least preferred seed species, based on preferences determined in this study. We then conducted a field experiment in a pocket mouseādominated ecosystem with the same 3-species seed mixtures in both ātreatedā (reduced shrub and increased forb cover) and āuntreatedā shrubsteppe. In the arena experiment, we found that rodents removed more of the highly preferred seed when the proportions of all 3 seeds were equal. Moderately preferred seeds experienced increased removal when the least preferred seed was in highest proportion. Removal of the least preferred seed increased when the highly preferred seed was in highest proportion. In the field experiment, results were similar to those from the arena experiment and did not differ between treated and untreated shrubsteppe areas. Though our results suggest that 3-species mixtures induce complex interactions among seeds, managers applying these results to restoration efforts should carefully consider the rodent community present and the potential fate of removed seeds
Healing Through History: a qualitative evaluation of a social medicine consultation curriculum for internal medicine residents
Background: Social context guides care; stories sustain meaning; neither is routinely prioritized in residency training. Healing Through History (HTH) is a social medicine consultation curriculum integrating social determinants of health narrative into clinical care for medically and socially complex patients. The curriculum is part of an internal medicine (IM) residency outpatient clinical rotation at a Veterans Health Administration hospital. Our aim was to explore how in-depth social medicine consultations may impact resident clinical practice and foster meaning in work. Methods: From 2017 to 2019, 49 categorical and preliminary residents in their first year of IM training were given two half-day sessions to identify and interview a patient; develop a co-produced social medicine narrative; review it with patient and faculty; and share it in the electronic health record (EHR). Medical anthropologists conducted separate 90-min focus groups of first- and second-year IM residents in 2019, 1ā15 months from the experience. Results: 46 (94%) completed HTH consultations, of which 40 (87%) were approved by patients and published in the EHR. 12 (46%) categorical IM residents participated in focus groups; 6 PGY1, and 6 PGY2. Qualitative analysis yielded 3 themes: patient connection, insight, and clinical impact; clinical skill development; and structural barriers to the practice of social medicine. Conclusions: HTH offers a model for teaching co-production through social and narrative medicine consultation in complex clinical care, while fostering meaning in work. Integration throughout training may further enhance impact
Substantial stores of sedimentary carbon held in mid-latitude fjords
This work was supported by the Natural Environment Research Council [Grant Number: NE/L501852/1].Quantifying marine sedimentary carbon stocks is key to improving our understanding of longterm storage of carbon in the coastal ocean and to further constraining the global carbon cycle. Here we present a methodological approach which combines seismic geophysics and geochemical measurements to quantitatively estimate the total stock of carbon held within marine sediment. Through the application of this methodology to Loch Sunart a fjord on the west coast of Scotland, we have generated the first full sedimentary carbon inventory for a fjordic system. The sediments of Loch Sunart hold 26.9 Ā± 0.5 Mt of carbon split between 11.5 Ā± 0.2 Mt and 15.0 Ā± 0.4 Mt of organic and inorganic carbon respectively. These new quantitative estimates of carbon stored in coastal sediments are significantly higher than previous estimates. Through an area normalised comparison to adjacent Scottish peatland carbon stocks we have determined that these midālatitude fjords are significantly more effective as carbon stores than their terrestrial counterparts. This initial work supports the concept that fjords are important environments for the burial and long-term storage of carbon and therefore should be considered and treated as unique environments within the global carbon cycle.Publisher PDFPeer reviewe
Comparing predictive abilities of longitudinal child growth models
Ā© 2018 John Wiley & Sons, Ltd. The Bill and Melinda Gates Foundation's Healthy Birth, Growth and Development knowledge integration project aims to improve the overall health and well-being of children across the world. The project aims to integrate information from multiple child growth studies to allow health professionals and policy makers to make informed decisions about interventions in lower and middle income countries. To achieve this goal, we must first understand the conditions that impact on the growth and development of children, and this requires sensible models for characterising different growth patterns. The contribution of this paper is to provide a quantitative comparison of the predictive abilities of various statistical growth modelling techniques based on a novel leave-one-out validation approach. The majority of existing studies have used raw growth data for modelling, but we show that fitting models to standardised data provide more accurate estimation and prediction. Our work is illustrated with an example from a study into child development in a middle income country in South America
- ā¦