To Cornell University professor Dr. Robert Howarth, nitrogen pollution is threatening America’s coastal waters — and the public could not care less.
“It’s not a sexy topic,” Howarth said, when asked why more people are not aware of nitrogen pollution’s potential danger.
Howarth discussed these problems and gave an overview of nitrogen pollution yesterday afternoon, in a talk entitled “Nitrogen Pollution in the U.S. — Trends in Sources, Fluxes, and Steps Toward Solution.”
Though oil pollution is a more glamorous and publicized issue, Howarth said based on his previous experience working with oil spills and oil cleanup operations — like those associated with the Exxon-Valdez spill — the danger from nitrogen is far greater than the danger from oil.
“We’ve actually had better control of oil pollution in the last 20 to 30 years,” he said. “Nitrogen is a far greater problem.”
Howarth said the amount of nitrogen on earth has increased explosively since 1960 because of waste created by humans.
“Humans are now in the range of matching the nitrogen production of nature,” he said.
Two-thirds of coastal rivers and bays in the United States are moderately to severely polluted because of excess nitrogen, Howarth said. The pollution causes eutrophication — the process by which waters rich in mineral and organic nutrients encourage the abundance of certain plant life, thereby choking off the oxygen needed by other organisms. This in turn reduces biodiversity. Other negative effects include acidification of freshwater bodies, ozone-related damage to forests, and nitrate carcinogens in drinking water.
However, Howarth admitted that some research still needs to be conducted to be completely sure of the magnitude of the danger.
“Seventy-five percent of nitrogen is not coming out of coastal waters,” he said. “At some point, it might saturate, and then we’re going to have a bigger problem. But if it is being denitrified, maybe it’s not so bad. We don’t know what’s going to happen.”
Nonetheless, Howarth said policy-makers should create policies to reduce nitrogen pollution regardless of the lack of information.
“Yes, we need more research, but don’t use it as an excuse to not do anything now,” he said.
Such policies, Howarth said, are not only possible, but affordable. He said the country only lacks the political will to create policies that tighten emission standards from vehicle exhaust and power plants, improve sewage treatment, and reduce the fertilizer amounts and planting cycles used by farmers. All these, he claims, could drastically reduce the amount of nitrogen in the environment.
“Technical solutions for reducing nitrogen exist, from all known sources, at reasonable costs,” Howarth said.
The lecture was attended mostly by graduate students associated with the School of Forestry & Environmental Studies. Audience members said they found the lecture informative and relevant.
“Nitrogen pollution is a big issue,” Haiying Hu FES ’06 said. “It was good to see a scientist talk about this issue.”
Howarth’s was the final lecture in the series entitled “The Science and Policy of Coastal Eutrophication and Restoration,” organized by the Center for Coastal and Watershed Systems and the School of Forestry & Environmental Studies, and sponsored by the Curtis and Edith Munson Foundation. Martha Smith, director of the Center for Coastal and Watershed Systems, said the lecture was an overview of the other lectures in the series.
“The other ones focused each on a case study — for example, Chesapeake Bay or the Long Island Sound,” she said.
Howarth is the David R. Atkinson Professor of Ecology and Environmental Biology at Cornell University. He has also served as the editor-in-chief of the scientific journal “Biogeochemistry” for the past 20 years.