Cottage cheese (acid) whey is an effective amendment in sodic soil reclamation,
but the high chemical oxygen demand (COD) of whey is of concern in land
application. The objective of this research was to determine the fate of COD from
cottage cheese whey applied to a sodic soil. Treatments of 0, 25, 50, and 100 mm (0,
20, 40, and 80 Mg COD ha-1) of whey were applied to dry-unacclimated Freedom
silt loam (fine-silty, mixed, mesic, Xerollic Calciorthids) in greenhouse lysimeters.
The COD from lysimeter leachate at 1 m depth was monitored. Ninety days after
whey application, total accumulative leachate COD for 0-, 25-, and 50-mm whey
applications was not significantly different. Leachate COD concentrations from the
100-mm application reached 37% (29 400 mg COD L-1) of the applied whey COD.
Twenty-eight days after whey treatment, infiltration was reduced in all whey-treated
lysimeters, probably as a result of increased microbial activity. Barley (Hordeum
vulgare L cv. Ludd) grain yield was 0.0, 0.0, 0.44, and 0.26 kg m-2 and total dry
matter yield was 0.54, 0.72, 2.0, and 1.4 kg m-2 for the 0-, 25-, 50-, and 100-mm
treatments, respectively. Salts and/or organic overloading appeared to inhibit initial
barley growth in the 100-mm treatment. Results indicate a single 100-mm application
to be excessive in terms of organic matter and/or salts
