Passage V
In wetlands, the herbicides atrazine and alachlor are removed from the water by plant uptake or by adsorption onto soil particles and subsequent bacterial decomposition. Atrazine can also spontaneously break down to form deethylatrazine (DEA).
Three pairs of herbicide-free wetlands were established for a study: open water (O1, O2), submergent (S1, S2), and emergent (E1, E2), as described in Table 1. On 1 day, atrazine was added to O1, S1, and E1 and alachlor was added to O2, S2, and E2 to produce an initial herbicide concentration of 25 g/L in the water in each wetland. Atrazine, alachlor, and DEA concentrations in the water were measured at intervals over the next 120 days (see Figures 1-3).
27. Is the statement “Over the 120 days of the study, atrazine concentration was most reduced in the water in the open water wetland"supported by the data in Figure 1 ?
Your Answer is
Correct Answer is D
Explanation
Look at O1 in figure 1. At 120 days, the atrazine concentration in O1 is the highest, indicating that the atrazine reduction is not as much as in the other two wetlands, so the statement in the question is wrong