What is the effect of herbicide treatments on invertebrate populations?

Herbicide treatments can significantly impact invertebrate populations in aquatic environments. The correct interpretation of option B reflects the common effects observed following herbicide application. This option suggests that while the overall number of invertebrates may increase, the diversity or number of different species tends to diminish.

When herbicides are applied, they can eliminate or severely reduce specific aquatic plants, which serve as crucial habitat and food sources for various invertebrate species. The removal of certain vegetation can lead to an increase in some invertebrate populations that thrive in disturbed or altered environments, thereby resulting in an overall higher number of individuals. However, this can come at the expense of biodiversity, as the loss of plant diversity often leads to the decline or elimination of specialized invertebrate species that rely on those particular plants for survival.

In summary, herbicide treatments can create a scenario where some invertebrate populations flourish due to changes in habitat, while others decline or disappear, leading to an overall increase in number but a decrease in species richness.