Nonpoint source water pollution regulations in the United States The primary nutrients found in water due to nonpoint source pollution are nitrogen and phosphorus from fertilizers. An influx of these nutrients can lead to eutrophication within the water. This is when there is an excess of nutrients in water, thus leading to an explosion in the growth of algae. The algae can cover the lake and block sunlight from reaching the organisms below, typically killing them. NPS water pollution is regulated at the federal, state, and local level. Yet, the pollution persists and remains a significant problem. There are a number of reasons why current regulations have failed to
Plant tolerance to herbivory Using simulated herbivory allows for the control of environmental variables, but replicating natural herbivory is difficult, causing plants to respond differently from imposed and natural herbivory (Tiffin and Inouye 2000). Growing plants in the control environment of the greenhouse may also affect their response as it is still a novel environment to the plants. Even if the plots are grown in natural settings, the methods of excluding or including herbivores, such as using cages or pesticides, may also affect plant tolerance (Tiffin and Inouye 2000). Lastly, models have predicted that manipulated herbivory may actually result in less precise estimates of