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Full-Text Articles in Medicine and Health Sciences
Global-Scale Patterns In Anthropogenic Pb Contamination Reconstructed From Natural Archives, Samuel K. Marx, Shaqer Rashid, Nicola Stromsoe
Global-Scale Patterns In Anthropogenic Pb Contamination Reconstructed From Natural Archives, Samuel K. Marx, Shaqer Rashid, Nicola Stromsoe
Faculty of Science, Medicine and Health - Papers: part A
During the past two centuries metal loads in the Earth's atmosphere and ecosystems have increased significantly over pre-industrial levels. This has been associated with deleterious effects to ecosystem processes and human health. The magnitude of this toxic metal burden, as well as the spatial and temporal patterns of metal enrichment, is recorded in sedimentary archives across the globe. This paper presents a compilation of selected Pb contamination records from lakes (n = 10), peat mires (n = 10) and ice fields (n = 7) from Europe, North and South America, Asia, Australia and the Northern and Southern Hemisphere polar regions. …
On The Intrinsic Accuracy And Precision Of The Standardised Growth Curve (Sgc) And Global-Sgc (Gsgc) Methods For Equivalent Dose Determination: A Simulation Study, Jun Peng, Vasilis Pagonis, Bo Li
On The Intrinsic Accuracy And Precision Of The Standardised Growth Curve (Sgc) And Global-Sgc (Gsgc) Methods For Equivalent Dose Determination: A Simulation Study, Jun Peng, Vasilis Pagonis, Bo Li
Faculty of Science, Medicine and Health - Papers: part A
In optically stimulated luminescence (OSL) dating, the single aliquot regenerative-dose (SAR) method has been used extensively for determining equivalent doses (De) in quartz. A variation of the SAR method is the “standardised growth curve” (SGC) method, which has been used as an efficient procedure to save measurement time during dating studies. During the application of the SGC method one establishes the SGC and calculation of the De of an aliquot requires only measurement of the standardised natural dose signal. Recently, a “global standardised growth curve” (gSGC) method was developed as an improved version of the SGC procedure. During the application …
The Significance Of Carbon-Enriched Dust For Global Carbon Accounting, Nicholas P. Webb, Adrian Chappell, Craig L. Strong, Samuel K. Marx, Granth Mctainsh
The Significance Of Carbon-Enriched Dust For Global Carbon Accounting, Nicholas P. Webb, Adrian Chappell, Craig L. Strong, Samuel K. Marx, Granth Mctainsh
Faculty of Science, Medicine and Health - Papers: part A
Soil carbon stores amount to 54% of the terrestrial carbon pool and twice the atmospheric carbon pool, but soil organic carbon (SOC) can be transient. There is an ongoing debate about whether soils are a net source or sink of carbon, and understanding the role of aeolian processes in SOC erosion, transport and deposition is rudimentary. The impacts of SOC erosion by wind on the global carbon budget, and its importance for carbon accounting remain largely unknown. Current understanding of SOC losses to wind erosion is based on the assumption that the SOC content of eroded material is the same …
Global Change And Fire Regimes In Australia, Geoffrey J. Cary, Ross A. Bradstock, A Malcolm Gill, Richard J. Williams
Global Change And Fire Regimes In Australia, Geoffrey J. Cary, Ross A. Bradstock, A Malcolm Gill, Richard J. Williams
Faculty of Science, Medicine and Health - Papers: part A
Global change can be defined strictly in terms of changes in atmospheric composition, climate and land use (Walker and Steffen 1996), although broader definitions also include human population, economy and urbanisation (Steffen et al. 2004). In Australia, global change significantly affects the drivers of fire activity and there is potential for considerable changes in fire regimes. It is widely accepted that carbon dioxide (C02) concentration in the atmosphere is steadily increasing (see Steele et al. 2007), as is nitrous oxide (Forster et al. 2007). Atmospheric methane concentration has also risen significantly, but is now relatively constant (Beer et al. 2006). …
Identifying The Agricultural Imprint On The Global N2o Budget Using Stable Isotopes, T Perez, S E. Trumbore, S C. Tyler, P A. Matson, I Ortiz-Monasterio, T Rahn, D W T Griffith
Identifying The Agricultural Imprint On The Global N2o Budget Using Stable Isotopes, T Perez, S E. Trumbore, S C. Tyler, P A. Matson, I Ortiz-Monasterio, T Rahn, D W T Griffith
Faculty of Science, Medicine and Health - Papers: part A
Agricultural soils are the most important anthropogenic source of nitrous oxide to the atmosphere. We observed large shifts with time in the emission rate (from 170 to 16 ng N cm−2 h−1) and in δ15N of N2O emitted (from −46‰ to +5‰ relative to atmospheric N2) from a urea-fertilized and irrigated agricultural field in Mexico. We calculated overall instantaneous enrichment factors for the sampling period, which suggest that the microbial N2O production shifts from nitrification (week 1) to denitrification (week 2). Isotopic signatures of N2O emissions were …