From farm to filter: Restored wetlands remediate nitrogen pollution

[NeoGreen]

https://www.earthmagazine.org/article/farm-filter-restored-wetlands-remediate-nitrogen-pollution


Each summer, a dead zone appears off the coast of Louisiana in the Gulf of Mexico. Reds and oranges on this map indicate high concentrations of phytoplankton and sediment. Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio, 2004.

From farm to filter: Restored wetlands remediate nitrogen pollution
by Nia Hurst

Nitrogen giveth and nitrogen taketh away: It’s been estimated that roughly half of the world’s population today could not exist without nitrogen fertilization. Although land area on Earth remains roughly the same on human timescales, population continues to rise, requiring more intensive and rigorous use of existing agricultural land and the creation of more agricultural lands to meet the ever-growing demand for food. One way humanity has supported population growth is through the manipulation of nitrogen, a limiting nutrient in terrestrial ecosystems. In 1913, the advent of the Haber-Bosch process, which artificially converts nitrogen gas to bioavailable ammonia, revolutionized access to nitrogen and all but eliminated nitrogen limitation in terrestrial ecosystems. Now, nitrogen fertilizers are often heavily applied to croplands to increase plant growth and productivity.

The problem, however, is that nitrogen fertilizers don’t remain on agricultural lands. Much of what’s applied is washed into local waterways and eventually makes its way into larger water bodies. The Mississippi River, for example, delivers 1.5 million metric tons of nitrogen (60 percent of which is in the form of nitrate) per year to the Gulf of Mexico. Thus, despite the many benefits of nitrogen fertilization, nitrogen pollution of our aquatic systems has become pervasive, resulting in a range of detrimental impacts, from harmful algal blooms to enormous dead zones.

Wetland scientists have long suggested that wetlands — which, because of their filtration abilities, are sometimes called the “kidneys” of an ecosystem — could provide the panacea for the nitrogen problem. But few large-scale projects (besides those specifically designed for wastewater management) have been implemented to test this theory. Now, thanks to a wetland restoration project in Louisiana that’s been running since 1998, scientists have more evidence that restoration and reconnection of floodplain wetlands can significantly reduce nitrogen delivery to the Gulf of Mexico.

[mopinko]

1. hugelkultur!!

if farmers would ring their fields w hugelpiles, something they could be paid to do, this problem would be solved.
landscapers have to pay to dump waste, and they could be paying that to farmers. but waste management is lobbying against that.

better to keep it close to the fields. the decomposing landscape waste sucks it up, and later it can be returned to the fields.