Effect of Beef‐Feedlot‐Lagoon Water on Soil Chemical Properties and Growth and Composition of Corn Forage

Abstract

AbstractLand disposal of beef‐feedlot‐lagoon (runoff) water was studied. Rates of 0, 8, 15, 26, and 46 cm/year of lagoon water were applied during the summers of 1970 and 1971 by furrow irrigation to a silty clay loam soil. Corn (Zea mays L.) forage yield and plant content of N, P, K, Ca, Mg, and Na were measured. Surface soil samples and soil cores were taken from the plots after harvest each year.Electrical conductivity ranged from 1.6 to 7.6 (3.1 average) mmho/cm in the lagoon water applied at the study site and from 1.0 to 12.8 mmho/cm in samples taken from 12 Kansas feedlots. Electrical conductivities of extracts from saturated pastes of the surface soil samples were increased linearly by accumulative treatment both years. The 1970 and 1971 soil cores showed accumulations of NO3−‐N, P, K, and Na in the top 30 cm at all treatment rates. Movement of NO3−‐N and Na down to 100 cm was noted in the 1971 cores from plots receiving 46 cm/year. Ca and Mg in the soil cores were not affected by treatment either year. Corn forage yields were a linear function of treatment in 1970 and a quadratic function in 1971. The positive effect on yield both years was attributed to increased soil fertility; the relative decrease in 1971 at the 26 and 46 cm/year rates was attributed to increased soil salinity. Maximum yield and uptake of N and P were reached at the 15 cm/year disposal rate in 1971.