نتایج جستجو برای: anthropogenic source

تعداد نتایج: 440868  

2016
Luke Bridgestock Tina van de Flierdt Mark Rehkämper Maxence Paul Rob Middag Angela Milne Maeve C Lohan Alex R Baker Rosie Chance Roulin Khondoker Stanislav Strekopytov Emma Humphreys-Williams Eric P Achterberg Micha J A Rijkenberg Loes J A Gerringa Hein J W de Baar

Anthropogenic emissions completely overwhelmed natural marine lead (Pb) sources during the past century, predominantly due to leaded petrol usage. Here, based on Pb isotope measurements, we reassess the importance of natural and anthropogenic Pb sources to the tropical North Atlantic following the nearly complete global cessation of leaded petrol use. Significant proportions of up to 30-50% of ...

2012
M. R. Cave J. Wragg E. L. Ander

Potentially harmful elements (PHE) occur both naturally from geogenic sources and from anthropogenic derived pollution. Anthropogenic sources can be further categorised into those derived from point sources. A point source is a single identifiable source which is confined to a very small area such as that arising from disposal of waste material or from an industrial plant. Diffuse pollution ari...

Hoda Karimi, Maryam Mohammadi Roozbahani, Rezvan Sorooshnia, Soheil Sobhan Ardakani,

Background: Soil serves as a major reservoir for contaminants as it can bind to various chemicals. The aim of this study was to evaluate the levels of some metals (Cd, Cu, Fe and V) in soil samples collected from different stations of Ahvaz Industrial Complex II to determine the natural and anthropogenic contribution of metal in the soil. Methods: This was an experimental study that carried ou...

2008
D. J. Erickson R. T. Mills J. Gregg T. J. Blasing F. M. Hoffman R. J. Andres M. Devries Z. Zhu S. R. Kawa

[1] Monthly estimates of the global emissions of anthropogenic CO2 are presented. Approximating the seasonal CO2 emission cycle using a 2-harmonic Fourier series with coefficients as a function of latitude, the annual fluxes are decomposed into monthly flux estimates based on data for the United States and applied globally. These monthly anthropogenic CO2 flux estimates are then used to model a...

2012
Aron Stubbins Eran Hood Peter A. Raymond George R. Aiken Rachel L. Sleighter Peter J. Hernes David Butman Patrick G. Hatcher Robert G. Striegl Paul Schuster Hussain A. N. Abdulla Andrew W. Vermilyea Durelle T. Scott Robert G. M. Spencer

Glacier-derived dissolved organic matter represents a quantitatively significant source of ancient, yet highly bioavailable carbon to downstream ecosystems1. This finding runs counter to logical perceptions of age–reactivity relationships, in which the least reactive material withstands degradation the longest and is therefore the oldest2. The remnants of ancient peatlands and forests overrun b...

2015
Jill F. Kerrigan Daniel R. Engstrom Donald Yee Charles Sueper Paul R. Erickson Matthew Grandbois Kristopher McNeill William A. Arnold Chon-Lin Lee

Hydroxylated polybrominated diphenyl ethers (OH-BDEs) are a new class of contaminants of emerging concern, but the relative roles of natural and anthropogenic sources remain uncertain. Polybrominated diphenyl ethers (PBDEs) are used as brominated flame retardants, and they are a potential source of OH-BDEs via oxidative transformations. OH-BDEs are also natural products in marine systems. In th...

Gurugubelli Balakrishna Shamsh Pervez

The components and quantities of atmospheric dusts fallout has been reported to be the pollution indicator of large urban areas. The multiplicity and complexity of sources of atmospheric dusts in urban regions (e.g. industrial complexes composed of a variety of industrial processes, automobiles, construction activities etc.) has put forward the need of source apportionment of these sources indi...

2018
Xueru Guo Rui Zuo Li Meng Jinsheng Wang Yanguo Teng Xin Liu Minhua Chen

Globally, groundwater resources are being deteriorated by rapid social development. Thus, there is an urgent need to assess the combined impacts of natural and enhanced anthropogenic sources on groundwater chemistry. The aim of this study was to identify seasonal characteristics and spatial variations in anthropogenic and natural effects, to improve the understanding of major hydrogeochemical p...

Journal: :Molecular ecology 2010
Kathleen C Parker Dorset W Trapnell J L Hamrick Wendy C Hodgson Albert J Parker

Several Agave species have played an important ethnobotanical role since prehistory in Mesoamerica and semiarid areas to the north, including central Arizona. We examined genetic variation in relict Agave parryi populations northeast of the Mogollon Rim in Arizona, remnants from anthropogenic manipulation over 600 years ago. We used both allozymes and microsatellites to compare genetic variabil...

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