Monday, November 13, 2006

Long-Term Composted Biosolids Land Application Affects Rangeland Soils and Plants.

Jim Ippolito, Kenneth Barbarick, and Mark Paschke. Colorado State Univ, Dept of Soil and Crop Sciences, 200 W Lake St, Fort Collins, CO 80523

The city of Fort Collins, Colorado owns 10,390 ha of semi-arid rangeland for use in recycling municipal wastes via land application.  In 1991, a study was initiated to determine the potential short-term impacts of composted biosolids application on soils and vegetation.  Treatments consisted of 0, 2.5, 5, 10, 21, and 30 Mg composted biosolids ha-1 applied to 15 x 15 m plots.  All treatments were replicated four times.  In October 2002, the plots were divided in half with one half of each plot receiving rates identical to the 1991 application.  Soils and vegetation data were collected in June 2004 and June 2005 to access the short-term impacts of a repeated co-application and the long-term impacts of a single application on ecosystem dynamics.  Results will be discussed.