The afforestation of abandoned farmland significantly influences soil organic carbon (OC). However, the dynamics between OC inputs after afforestation and the original OC are not well understood. To learn more about soil OC dynamics after afforestation of farmland, we measured the soil OC content in paired forest and farmland plots in Shaanxi Province, China. The forest plots had been establish...

The revegetation of abandoned farmland significantly influences soil organic C (SOC) and total N (TN). However, the dynamics of both soil OC and N storage following the abandonment of farmland are not well understood. To learn more about soil C and N storages dynamics 30 years after the conversion of farmland to grassland, we measured SOC and TN content in paired grassland and farmland sites in...

Recent findings have confirmed the importance of black carbon (BC) in the global biogeochemical cycles of carbon and oxygen through its important contribution to the slowly cycling organic carbon (OC) pool. Yet, most BC determination methods published to date measure operationally defined BC fractions, oftentimes with a high potential for artifacts and a lack of specificity for one of the two m...

The Mediterranean Sea (MS) is a large oligotrophic sea whose productivity sensitive to riverine nutrient inputs. More specifically, phosphorus (P) river supply crucial for the MS, with an important role of estuarine/deltaic filter especially storage and recycling in sediments. A benthic dataset from Rhône River prodelta was used derive P budgets, by means early diagenetic model including cycle....

The sorption behaviors of 4 cyclic and linear volatile methyl siloxane (VMS) compounds between water and organic matter in 3 United Kingdom soils were studied by a batch equilibrium method using(13)C-enriched sorbates. Sorption and desorption kinetics and isotherms were determined for octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), octamethyltrisiloxane (L3), and decamethy...

Although acute adverse effects on asthma have been frequently found for the U.S. Environmental Protection Agency's principal criteria air pollutants, there is little epidemiologic information on specific hydrocarbons from toxic emission sources. We conducted a panel study of 22 Hispanic children with asthma who were 10-16 years old and living in a Los Angeles community with high traffic density...

Carbonaceous aerosols are present in many workplace and environmental settings. Some of these aerosols are known or suspect human carcinogens and have been linked to other adverse health effects. Exposure to diesel exhaust is of particular concern because it has been classified as a probable human carcinogen and use of diesel-powered equipment is widespread in industry. Because previously used ...

Understanding the organic matter/organic carbon (OM/OC) ratio in ambient particulate matter (PM) is critical to achieve mass closure in routine PM measurements, to assess the sources of and the degree of chemical processing organic aerosol particles have undergone, and to relate ambient pollutant concentrations to health effects. Of particular interest is how the OM/OC ratio varies in the urban...

Continuous measurements of atmospheric organic and elemental carbon (OC and EC) were taken during the high-pollution fall and winter seasons at Xi’an, Shaanxi Province, China from September 2003 through February 2004. Battery-powered mini-volume samplers collected PM2.5 samples daily and PM10 samples every third day. Samples were also obtained from the plumes of residential coal combustion, mot...