Global airborne bacterial community-interactions with Earth's microbiomes and anthropogenic activities.

Airborne bacteria are an influential component of the Earth's microbiomes, but their community structure and biogeographic distribution patterns have yet to be understood. We analyzed the bacterial communities of 370 air particulate samples collected from 63 sites around the world and constructed an airborne bacterial reference catalog with more than 27 million nonredundant 16S ribosomal RNA (rRNA) gene sequences. We present their biogeographic pattern and decipher the interlacing of the microbiome co-occurrence network with surface environments of the Earth.

Particulate-phase mercury emissions from biomass burning and impact on resulting deposition: a modelling assessment.

Mercury (Hg) emissions from biomass burning (BB) are an important source of atmospheric Hg and a major factor driving the interannual variation of Hg concentrations in the troposphere. The greatest fraction of Hg from BB is released in the form of elemental . However, little is known about the fraction of Hg bound to particulate matter (Hg) released from BB, and the factors controlling this fraction are also uncertain.

Atmospheric mercury concentrations observed at ground-based monitoring sites globally distributed in the framework of the GMOS network.

Long-term monitoring of data of ambient mercury (Hg) on a global scale to assess its emission, transport, atmospheric chemistry, and deposition processes is vital to understanding the impact of Hg pollution on the environment. The Global Mercury Observation System (GMOS) project was funded by the European Commission (http://www.gmos.

Mercury contamination in fish and human hair from Hainan Island, South China Sea: Implication for human exposure.

Hair has long been recognized as a good biomarker for human exposure to Hg. The mercury concentrations in 14 species of marine fish and hair samples from 177 coastal residents in Hainan, South China Sea were investigated to assess the status of mercury exposure associated with marine fish consumption. Concentrations of total Hg (THg) and methylmercury (MeHg) in the fish muscles were 0.

Atmospheric mercury inputs in montane soils increase with elevation: evidence from mercury isotope signatures.

The influence of topography on the biogeochemical cycle of mercury (Hg) has received relatively little attention. Here, we report the measurement of Hg species and their corresponding isotope composition in soil sampled along an elevational gradient transect on Mt. Leigong in subtropical southwestern China.

In vivo mercury methylation and demethylation in freshwater tilapia quantified by mercury stable isotopes.

In vivo methylation and demethylation processes were simultaneously investigated in freshwater tilapia after dietary exposure to mercury ((198)Hg(II) and methyl(200)Hg). During one month dietary exposure followed by two month depuration, both MeHg and THg increased continuously in muscle tissues but decreased in liver during depuration, indicating the inter-organ transportation of MeHg from liver toward muscle. Direct evidence of in vivo net methylation process in freshwater tilapia was observed.

[Geochemical cycling of mercury in the sediment of Hongfeng Reservior].

Spatial and temporal distributions of total and methyl mercury and controlling factors were investigated based on cold vapor atomic fluorescence detection. Total mercury levels in the whole sediments are (0.392 +/- 0.

[Seasonal variation of total gaseous mercury in Changbai Mountain area].

An intensive field campaign monitoring was conducted from August 2005 to July 2006 using the automatic atmospheric mercury analyzers for one year' s measurement of total gaseous mercury (TGM) in Changbai Mountain area. Results show the mean concentration of TGM is (3.22 +/- 1.

[Mercury exchange fluxes between air and soil interface over different type of land in Wanshan Hg mine area].

Air/soil Hg exchange fluxes were measured using field chamber-automated air mercury analyzer method over different land in Wanshan Hg mine area in two seasons. The results showed that the air/soil Hg exchange fluxes were very strong. The highest Hg emission flux from soil was 27 827 ng/(m2 x h), the highest Hg deposition flux from the atmosphere was 9 434 ng/(m2 x h).

[Mercury emission from the indigenous method of mercury smelting in Wuchuan mercury mining areas, Guizhou Province].

By determining mercury concentrations in mercury ore and smelting slag samples, we used a mass balance method to calculate mercury emission factors and annual mercury emission from the indigenous method of mercury smelting in Wuchuan mercury mining areas, Guizhou Province. The mercury emission factors of the indigenous method ranged from 6.9% to 32.

[Evaluation of phytoavailability of zinc and cadmium in contaminated soils by a short sequential extraction procedure].

Cultivated soils and maize samples from heavy metal contaminated locations affected by zinc smelting activities were collected in Hezhang County, Guizhou Province. Chemical fractions of zinc and cadmium (extracted by 0.01 mol x L(-1) CaCl2 and 0.

[Pathways of mercury emissions to atmosphere from closed municipal landfills].

Using the automated mercury vapor analyzer and dynamic flux chamber (DFC) method, the pathways of mercury emissions to atmosphere were measured at a closed landfill in Wuhan, China. The results show that the mainly pathway is by the surface cover, and emissions from vent pipes is negligible. Average Hg fluxes during the observation period was (192.

[Comparison of air/soil mercury exchange between warm and cold season in Hongfeng Reservoir region].

In July 2002 and March 2003, the mercury exchange flux between soil and air was measured using dynamic flux chamber method in Hongfeng Reservoir region. Mercury exchange flux is (27.4 +/- 40.