Adding any chemicals to the soil, can have far-reaching effects due to the fact that producers rely on soil for their growth. Therefore, any added potassium or nitrates will fertilize the soil and enable plants to proliferate. This in turn affects herbivores that use them for their food at that trophic level. Increased herbivores means more food for carnivores, thus the entire food web in the area is affected. Agrochemicals can also include fungicides, herbicides and insecticides, to control pests. However, as water infiltrates the soil, it will also have dissolved agrochemicals in it. Eventually, because water flows downhill due to gravity, the water table will contain some of these chemicals. Thus, anyone pulling well water out of the ground, could have levels of substances that may become toxic to human health. Also, water flows eventually to rivers and oceans, and this may increase the algae levels causing a bloom, and a subsequent die-off, eventually causing the oxygen levels to decrease as bacterial decomposition increases. For every action, there is always a trade-off.