@inbook {JRN52670,
	title = {Long-term trends in precipitation and surface water chemistry},
	booktitle = {Long-Term Trends in Ecological Systems: A Basis for Understanding Responses to Global Change},
	year = {2013},
	pages = {115-161},
	publisher = {National Technical Information Services},
	organization = {National Technical Information Services},
	chapter = {12},
	address = {Springfield, Virginia},
	abstract = {<p>This chapter shows long-term data and trends in precipitation and surface water chemistry for each site.\&nbsp; It contains a brief introduction to the topic, and methods of measurements, selection of variables, and their data source. It consists primarily of a large number of figures showing long-term data for different variables.\&nbsp; Volume-weighted concentration (mg/L) and area-based wet deposition (kg/ha) from precipitation, and concentration in surface water (mg/L) of nitrogen (as nitrate and ammonium), sulfur (as sulfate), chloride, and calcium are selected.\&nbsp; Two types of graphs are included to show trends in the variables and to provide a sense of change across a range of spatial scales (continent, site) for each variable: maps at continental scale showing either the mean across years or the slope of the regression line (if significant) across time, and site-scale data through time.\&nbsp; Nitrate and sulfate deposition are decreasing in many Eastern sites, consistent with efforts to control emissions of acid-causing nitrogen and sulfur from power plants in this part of the country.</p>
},
	keywords = {atmospheric chemistry, climate change, cross-site comparisons, disturbance, ecological response, ecology, ecosystem, EcoTrends, experimental forests, global change, human demography, human population growth, Long Term Ecological Research (LTER), long-term datasets, precipitation, rangeland, rangeland research stations, surface water chemistry},
	url = {/files/bibliography/13-029-12.pdf},
	author = {Debra C. Peters and C. Laney and Ariel E. Lugo and S.L. Collins and Charles T. Driscoll and Peter M. Groffman and Grove, J. Morgan and A. K. Knapp and T. K. Kratz and Mark D. Ohman}
}
