Browse on keywords: fertility heavy metals
Search results on 12/06/13
26. Lerch, R.N., K.A. Barbarick, D.G. Westfall, R.H. Follett, T.M. McBride, and W.F. Owen. 1990. Sustainable rates of sewage sludge for dryland winter wheat production. 2. Production and income.. J. Production Agric. 3:66-71.
A sewage sludge application rate of 3 T/ac on hard red winter wheat increased gross income by an average of $45/ac/year compared to wheat grown with the typical 50-60 lb fertilizer N/ac. This was primarily due to premiums paid for higher grain protein. Grain levels of P an Zn were increased by sludge application, while levels of Cd, Ni, and Pb have remained low.
82. Lerch, R.N., K.A. Barbarick, D.G. Westfall, R.H. Follett, T.M. McBride, and W.F. Owen. 1990. Sustainable rates of sewage sludge for dryland winter wheat production. 1. Soil nitrogen and heavy metals.. J. Production Agric. 3:60-65.
This study determined that a 3 T/ac rate was the maximum allowable for the dryland wheat-fallow system. The sludge significantly increased heavy metal concentrations in the soil at all loading rates. Increased ntirates in the root zone resulted from a 12 T/ac sludge rate, compared to a 50 lb N/ac fertilizer application.