Our goal is to understand how microbial behavior influences the mechanical stability of illuminated littoral marine sediments. We define “behavior” as the interaction of bacteria and diatoms with environmental signals that are either autoproduced, or arise from another source. A further goal is to investigate whether these processes, which define sediment optical signatures, can be influenced b...

The isotopic fingerprint of the pre-industrial and the anthropogenic N2O source T. Röckmann, J. Kaiser, and C. A. M. Brenninkmeijer Max Planck Institute for Nuclear Physics, Atmospheric Physics Division, Heidelberg, Germany Max Planck Institute for Chemistry, Air Chemistry Division, Mainz, Germany Received: 21 August 2002 – Accepted: 21 October 2002 – Published: 13 November 2002 Correspondence ...

Anthropogenic enrichment of reactive nitrogen (Nr) deposition is an ecological concern. We use the adjoint of a global 3-D chemical transport model (GEOS-Chem) to identify the sources and processes that control Nr deposition to an ensemble of biodiversity hotspots worldwide and two U.S. national parks (Cuyahoga and Rocky Mountain). We find that anthropogenic sources dominate deposition at all c...

Urban environments offer wildlife novel anthropogenic resources that vary spatiotemporally at fine scales. Property damage, economic losses, human injury, or other human-wildlife conflicts can occur when wildlife use these resources; however, few studies have examined urban wildlife resource selection at fine scales to guide conflict mitigation. We studied black bears (Ursus americanus) in the ...

Much attention has been paid to the impacts of plastics and other debris on marine organisms, but the effects of plastic on terrestrial organisms have been largely ignored. Detrimental effects of terrestrial plastic could be most pronounced in intensively human-modified landscapes (e.g., urban and agricultural areas), which are a source of much anthropogenic debris. Here, we examine the occurre...

This paper provides an up-to-date assessment of global mercury emissions from anthropogenic and natural sources. On an annual basis, natural sources account for 5207 Mg of mercury released to the global atmosphere, including the contribution from re-emission processes, which are emissions of previously deposited mercury originating from anthropogenic and natural sources, and primary emissions f...

[1] Mineral dust interacts with radiation and impacts both the regional and global climate. The relative contribution of natural and anthropogenic dust sources, however, remains largely uncertain. Although human activities disturb soils and therefore enhance wind erosion, their contribution to global dust emission has never been directly evaluated because of a lack of data. The retrieval of aer...

by Pavel Povinec, Scott Fowler, and Murdoch Baxter I he Chernobyl nuclear accident in April 1986 had a significant impact on both the terrestrial and marine environments. The total activity of the nuclear debris released was so high (1-2.10 becquerel) that the radioactive fallout distributed widely after the accident actually dominated anthropogenic environmental levels in various parts of the ...

Surface sediment samples (0-5 cm) from 5 tidal salt marshes along the coast in California, USA were analyzed to investigate the occurrence and anthropogenic input of trace metals. Among study areas, Stege Marsh located in the central San Francisco Bay was the most contaminated marsh. Concentrations of metals in Stege Marsh sediments were higher than San Francisco Bay ambient levels. Zinc (55.3-...