Tillage Management and Soil Organic Matter, 2005

Tillage systems play a significant role in agricultural production throughout Iowa and the Midwest. It has been well documented that increased tillage intensities can reduce soil organic matter in the topsoil due to increased microbial activity and carbon (C ) oxidation. The potential loss of soil organic matter due to tillage operations is much higher for high organic matter soils than low organic matter soils. Tillage effects on soil organic matter can be magnified through soil erosion and loss of soil productivity. Soil organic matter is a natural reservoir for nutrients, buffers against soil erosion, and improves the soil environment to sustain soil productivity. Maintaining soil productivity requires an agriculture management system that maintains or improves soil organic matter content. Combining cropping systems and conservation tillage practices, such as no-tillage, strip-tillage, or ridge-tillage, are proven to be very effective in improving soil organic matter and soil quality.

Global Prospects for Dairy in Argentina and Chile: Evidence from Field Visits and Model Simulations, August 2006

We assess the international competitiveness of the dairy industries in Argentina and Chile, combining recent market intelligence gathered from field visits with quantitative simulations of global policy reform scenarios. Both countries exhibit strong potential for export growth but face significant internal and external barriers to expanding their dairy industries. Global policy reforms would resolve some of the international obstacles to their expansion. Argentina has great potential, but it is handicapped by its current macroeconomic policies, trade policy distortions, and the uncertainty associated with policy implementation. Chile is more limited in terms of natural capacity for expansion, but it has a positive trade and investment environment.

Does Health Information Matter for Modifying Consumption?, October 2006

A field experiment was conducted in France to evaluate the impact of health information on fish consumption. A warning given to the treatment group revealed the risks of methylmercury contamination in fish and also gave consumption recommendations. Using difference-indifferences estimation, we show that this warning led to a significant but relatively weak decrease in fish consumption. However, consumption of the most contaminated fish did not decrease despite advice to avoid consumption of these types of fish. Accompanying questionnaires show that consumers imperfectly memorize the fish species quoted in the warning. The results point to the relatively poor efficacy of a complex health message, despite its use by health agencies around the world.

Hydrologic Simulations of the Maquoketa River Watershed Using SWAT Working Paper 09-WP 49,June 2009

This paper describes the application of the Soil and Water Assessment Tool (SWAT) model to the Maquoketa River watershed, located in northeast Iowa. The inputs to the model were obtained from the Environmental Protection Agency’s geographic information/database system called Better Assessment Science Integrating Point and Nonpoint Sources (BASINS). Climatic data from six weather stations located in and around the watershed, and measured streamflow data from a U.S. Geological Survey gage station at the watershed outlet were used in the sensitivity analysis of SWAT model parameters as well as its calibration and validation for watershed hydrology and streamflow. A sensitivity analysis was performed using an influence coefficient method to evaluate surface runoff and base flow variations in response to changes in model input hydrologic parameters. The curve number, evaporation compensation factor, and soil available water capacity were found to be the most sensitive parameters among eight selected parameters when applying SWAT to the Maquoketa River watershed. Model calibration, facilitated by the sensitivity analysis, was performed for the period 1988 through 1993, and validation was performed for 1982 through 1987. The model performance was evaluated by well-established statistical methods and was found to explain at least 86% and 69% of the variability in the measured stream flow data for the calibration and validation periods, respectively. This initial hydrologic modeling analysis will facilitate future applications of SWAT to the Maquoketa River watershed for various watershed analysis, including water quality.

A Matter of Substance, January 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, April 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, July 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, August 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, October 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, September 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, November 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, December 2009.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, January 2010.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, March 2010.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.

A Matter of Substance, May 2010.

A publication of the IDPH Division of Behavioral Health to find out what's happening with Substance Abuse Prevention and Treatment.