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D. Schmeltz

Publications and source records attributed to D. Schmeltz.

3 recordsLinked to original sources

MercNet: A national monitoring network to assess responses to changing mercury emissions in the United States

A partnership of federal and state agencies, tribes, industry, and scientists from academic research and environmental organizations is establishing a national, policy-relevant mercury monitoring network, called MercNet, to address key questions concerning changes in anthropogenic mercury emissions and deposition, associated linkages to ecosystem effects, and recovery from mercury contamination. This network would quantify mercury in the atmosphere, land, water, and biota in terrestrial, freshwater, and coastal ecosystems to provide a national scientific capability for evaluating the benefits and effectiveness of emission controls. Program development began with two workshops, convened to establish network goals, to select key indicators for monitoring, to propose a geographic network of monitoring sites, and to design a monitoring plan. MercNet relies strongly on multi-institutional partnerships to secure the capabilities and comprehensive data that are needed to develop, calibrate, and refine predictive mercury models and to guide effective management. Ongoing collaborative efforts include the: (1) development of regional multi-media databases on mercury in the Laurentian Great Lakes, northeastern United States, and eastern Canada; (2) syntheses and reporting of these data for the scientific and policy communities; and (3) evaluation of potential monitoring sites. The MercNet approach could be applied to the development of other monitoring programs, such as emerging efforts to monitor and assess global mercury emission controls.

Ecotoxicology

Results of the acid rain program: Status and trends of emissions and environmental impacts (1990–2002)

Both SO2 and NOx emissions from power generation sources have significantly declined under Title IV. In 2002, SO2 emissions from Title IV-affected sources totaled 10.2 million tons and NOx emissions from all Title IV-affected sources totaled 4.5 million tons, down 35% and 33% respectively from 1990 levels. Sources in states with the highest emissions continue to reduce their emissions the most, and there have been no significant geographic shifts in emissions. The benefits of these emission reductions include improvements in air quality (which are expected to lead to significant human health benefits), broad-scale reductions in sulfate deposition, and improvements in visibility. While surface waters in some areas have begun to show signs of recovery from acidification, acidification is still occurring in many areas. Although there have been no broad-scale regional reductions in nitrogen deposition, nitrogen deposition has declined in some areas, benefiting some nitrogen-sensitive forests and coastal waters and acid-sensitive lakes and streams.

Book chapter

Assessing acid deposition: Advances in the state of science

NAPAP has a long history of conducting research related to acid deposition. Throughout the 1980s NAPAP supported a large number of research projects that confirmed the link between SO 2 and NO x emissions and acidic lakes and streams hundreds of miles away. Recent research is confirming the tight link between emissions of SO 2 and the amount of several different forms of sulfur in the atmosphere and in precipitation, and improving our ability to measure acid deposition. Research has continued since 1990, albeit on a smaller scale, to increase our understanding of how acid deposition affects trees, soils, lakes, streams, coastal waters, and building materials such as stone and copper. Some of the areas where the most research has been done include: the importance of calcium in mediating soil and forest response to acidification; the role of nitrogen in acidification and recovery from acidification; and the role of nitrogen deposition in coastal ecosystems. In addition, substantial advances have been made in understanding the human health impacts of fine particles, including sulfates and nitrates, which are briefly mentioned here.

Book chapter