Too much carbon dioxide may not be the only thing that is not good for our planet. Experts believe that the increase in phosphorous and nitrogen being used in industrial fertilizers could be worse.
Stephen Carpenter, director of the Center for Limnology at the University of Wisconsin-Madison, says Western agriculture requires using far more fertilizer than farmers actually need to produce adequate crops. Carpenter, a limnologist, or one who studies inland waters, says the lands in the United States are naturally rich in phosphorus and nitrogen that there is no need to use excessive amounts of fertilizers, warning that it could push the Earth beyond its "planetary boundaries" if farmers continue the profligate use of fertilizers.
"We've changed nitrogen and phosphorus cycles vastly more than any other element," says Carpenter. "(The increase) is on the order of 200 to 300 percent. In contrast, carbon has only been increased 10 to 20 percent and look at all the uproar that has caused in the climate."
This is particularly harmful to water quality, he says, as phosphorus and nitrogen runoff are washed into waterways, over-fertilizing lakes and reservoirs and creating low-oxygen areas called dead zones, such as those found in Lake Erie and the Gulf of Mexico, and promoting the growth of harmful algal blooms.
It's a "distribution problem," says Carpenter. He explains that while American lands may have enough phosphorus and nitrogen to fertilize farmlands, other places such as Africa are largely lacking in these elements, which explains the problems Africans have with providing adequate food without the use of fertilizers.
"We've got certain parts of the world that are over-polluted with nitrogen and phosphorus, and others where people don't even have enough to grow the food they need," says Carpenter.
Carpenter's recommendation is for Western industrial farmers, especially those in the Midwestern U.S., to cut down on the excessive use of artificial fertilizers because the extra phosphorus and nitrogen knocks out the balance of the ecosystem, while nutrient-poor regions increase their use of these elements.
For thousands of years, throughout the entire Holocene period until the early 1900s, Carpenter says the Earth's ecosystem had been in a "remarkably stable state," which paved the way for "everything important to civilization," including the invention of agriculture, the rise and fall of the Roman Empire, and the Industrial Revolution. By the start of the 20th century, however, man's activities began to tilt the balance of the ecosystem, Carpenter says.
"We are simply saying that since the Holocene had great conditions for human civilization and we are now causing many planetary conditions to exceed those boundaries into new and different ranges, we're not sure what that will mean for human civilization," says Adam Hinterthuer, a spokesperson for the Center of Limnology, in a statement to Tech Times.
Carpenter and his colleagues have recently published a paper in the scientific magazine Science, where the researchers discuss the various ways we humans are rendering our planet inhabitable. The report, which will be presented at the World Economic Forum in Davos, Switzerland next week, also discusses other topics such as biodiversity loss and climate change caused by global warming.