Mercury and Methylmercury Concentrations and Litterfall Mass in Autumn Litterfall Samples Collected at Selected National Atmospheric Deposition Program Sites in 2007-2009 and 2012-2015
Dates
Publication Date
2017-04-14
Time Period
2007
Time Period
2015
Citation
Risch, Martin, 2017, Mercury and Methylmercury Concentrations and Litterfall Mass in Autumn Litterfall Samples Collected at Selected National Atmospheric Deposition Program Sites in 2007-2009 and 2012-2015: U.S. Geological Survey data release, https://doi.org/10.5066/F7KH0KHT.
Summary
Mercury (Hg) is a persistent environmental contaminant and can accumulate and concentrate in food webs as methylmercury (MeHg), presenting a health risk to humans and wildlife. Multiyear monitoring and modeling studies have shown that atmospheric Hg in litterfall is an important form of Hg deposition to forests. Annual litterfall consists primarily of leaves with some amounts of needles, twigs, bark, flowers, seeds, fruits, and nuts. Atmospheric Hg accumulates in leaves and reaches an annual maximum concentration at autumn leaf drop. This data set is derived from autumn litterfall collected at 30 selected National Atmospheric Deposition Program (NADP) Mercury Deposition Network (MDN) sites in deciduous and mixed deciduous-coniferous [...]
Summary
Mercury (Hg) is a persistent environmental contaminant and can accumulate and concentrate in food webs as methylmercury (MeHg), presenting a health risk to humans and wildlife. Multiyear monitoring and modeling studies have shown that atmospheric Hg in litterfall is an important form of Hg deposition to forests. Annual litterfall consists primarily of leaves with some amounts of needles, twigs, bark, flowers, seeds, fruits, and nuts. Atmospheric Hg accumulates in leaves and reaches an annual maximum concentration at autumn leaf drop. This data set is derived from autumn litterfall collected at 30 selected National Atmospheric Deposition Program (NADP) Mercury Deposition Network (MDN) sites in deciduous and mixed deciduous-coniferous forests from 16 states in the eastern United States during 2007-2009 and 2012-2015. The NADP administered litterfall collection at the MDN sites. The U.S. Geological Survey (USGS) distributed sets of passive litterfall sample collectors to MDN site operators for systematic retrieval of samples during the 8 to 16 weeks of autumn leaf drop each year at each site. Samples were processed and analyzed at the USGS Mercury Research Laboratory where concentrations of Hg and MeHg and litterfall dry mass and sample moisture were determined. All sites did not have data for all years. Most sites had four Hg concentrations per year and a few sites had less than or more than four Hg concentrations in specific years. MeHg concentrations were determined in one composite sample per site in 2007 and 2012-2015. Litterfall mass was determined from 4 to 8 samples per site per year. Seven annual groups of data were compiled into this dataset. More information is available from the NADP at http://nadp.sws.uiuc.edu/
Click on title to download individual files attached to this item.
Litterfall Data at NADP Sites Final.xml Original FGDC Metadata
View
12.38 KB
application/fgdc+xml
Litterfall Data at NADP Sites Final.csv
19.17 KB
text/csv
Purpose
Information for 23 sites during 2007-2009 from this dataset were interpreted by Risch et al. (2012, http://dx.doi.org/10.1016/j.envpol.2011.06.005). Information for 27 sites during 2007-2009 and 2012-2014 from this dataset were interpreted for a study about atmospheric mercury deposition to forests in the eastern USA, with a publication in review as of January 2017. Information for 18 sites during 2015 from this dataset have not been interpreted for publication as of January 2017.