These sources of non-point pollution can transport more than just nutrients to receiving waters: Pesticides from agricultural and suburban uses, bacteria and pathogens (e.g., E.
EPA’s 2000 National Water Quality Inventory showed that, of the U. water bodies assessed, 47 percent of rivers, 53 percent of lakes, and 52 percent of estuaries were polluted or threatened.
In 19, nutrients and siltation (sedimentation) were among the top five causes of impairment for streams, rivers, lakes, ponds, reservoirs, and estuaries.
As such, project managers focused efforts on educating stakeholders on the complexity and differences of different pollutant transport.
To be fair, this discrepancy in attitudes between water quality managers and stakeholders toward water resources is not unique to farming communities.
These harmful algal blooms (HABs) can produce potent toxins, and scientists have implicated them in wildlife, livestock, and pet deaths after the animals had drunk contaminated water.
Long-term low dose exposures of a hepatotoxin, microcystins-LR produced by HABs of Microcystis, is suspected to contribute to high rates of liver cancer in certain parts of China.
Eutrophication, or cultural eutrophication, is the enhancement of the natural process by which streams, lakes, reservoirs, and estuaries become enriched with nutrients (phosphorous and nitrogen), enabling the ecosystem to support higher rates of production as measured by biomass or energy per unit area over time.
This natural process of enrichment can take thousands of years and result in the succession of a glacial lake into a bog and, eventually, a prairie.
However, this process can be greatly accelerated by human activities; while natural eutrophication occurs on geologic timescales, a reservoir undergoing cultural eutrophication can evolve into a bog in less than a hundred years.
This accelerated enrichment can have many detrimental ecological, aesthetic, and human health effects.