Copper contamination as well as the oxytetracycline/
captan treatment reduced the majority of soil respiration
rates, but to different degrees in the two soil types
(Table 2). The mean soil respiration rate in treatments with
the highest Cu concentration and oxytetracycline/captan
was 42% of the control rate for UP soil, but only 28% for P
soil. The P soil controls had a higher respiration rate than
UP soil controls, but after Cu treatment the decrease of the
respiration rate was larger for P soil than for UP soil
(Fig. 2a).