Connect with us

Hi, what are you looking for?

CleanTechnica

Agriculture

Worse Than Acid Rain? Agricultural Sulfur Is Wreaking Havoc On Our Ecosystems

A new study says that the amount of agricultural sulfur is up to 10 times higher than peak load during time of acid rain.

For the longest time, coal-fired power plants were the greatest source of reactive sulfur (think: acid rain) to the biosphere. A new study reveals that that fertilizer and pesticide applications to croplands have overtaken coal as the most significant source of sulfur to health and the environment. Rachel Carson must be weeping from the grave as agricultural sulfur contaminates human and wildlife ecosystems.

The study, published in the journal Nature Geoscience, is titled, “A Shift in Sulfur-Cycle Manipulation from Atmospheric Emissions to Agricultural Additions.” The authors outline how emissions of sulfur dioxide and reactive sulfur to the atmosphere have caused widespread health and environmental impacts. Yet calls to decrease sulfur emissions through anthropogenic modification of the sulfur cycle aren’t over.

Instead, the study indicated that high levels of sulfur are added to croplands as fertilizers and pesticides and constitute a major environmental disturbance. Long-term sulfur additions to crops have consequences for the health of soil and downstream aquatic ecosystems just as those impacted by acid rain.

Agricultural Sulfur

Image retrieved from PA Dept. of Agriculture

Acid Rain’s Insidious Effects on Ecosystems

Acid rain results when sulfur dioxide (SO2) and nitrogen oxides (NOX) are emitted into the atmosphere and transported by wind and air currents. The SO2 and NOX react with water, oxygen, and other chemicals to form sulfuric and nitric acids. These then mix with water and other materials before falling to the ground.

Sulfur is a naturally occurring element that exists primarily in stable geologic forms and is an important plant nutrient. Through mining activities, including fossil fuel extraction as well as synthesis of fertilizers and pesticides, sulfur is brought into air, land, and water systems. It can react quickly, affect ecosystem health, and cycle toxic metals that pose a danger to wildlife and people.

Acid rain gained attention in the 1960s and 1970s when scientists linked degradation of forest and aquatic ecosystems across the northeastern US and Europe to fossil fuel emissions from industrial centers often hundreds of miles away. As it flows through the soil, acidic rain water can leach aluminum from soil clay particles and then flow into streams and lakes. The more acid that is introduced to the ecosystem, the more aluminum is released.

According to the EPA, at pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Some acidic lakes have no fish. Acid rain also removes minerals and nutrients from the soil that trees need to grow. At high elevations, acidic fog and clouds can strip nutrients from trees’ foliage, leaving them with brown or dead leaves and needles. The trees are then less able to absorb sunlight, which makes them weak and less able to withstand freezing temperatures.

acid rain pathway

This image retrieved from the EPA illustrates the pathway for acid rain in our environment: (1) Emissions of SO2 and NOx are released into the air, where (2) the pollutants are transformed into acid particles that may be transported long distances. (3) These acid particles then fall to the earth as wet and dry deposition (dust, rain, snow, etc.) and (4) may cause harmful effects on soil, forests, streams, and lakes.

It was thought that the Clean Air Act and its Amendments, which regulated air pollution, would drive down sulfur levels in atmospheric deposition so that there would be no further threat such as was evident through acid rain to ecosystems.

“It seemed like the sulfur story was over,” said Eve-Lyn Hinckley, assistant professor of environmental studies at the University of Colorado, Boulder and lead author of the study. “But our analysis shows that sulfur applications to croplands in the US and elsewhere are often ten times higher than the peak sulfur load in acid rain. No one has looked comprehensively at the environmental and human health consequences of these additions.”

Image of California vineyard retrieved from NASA

Agricultural Sulfur’s Detrimental Effects: Soils & Downstream Waters

Researchers from the University of Colorado, Boulder, University of Southern Illinois at Carbondale, and Syracuse University participated in this study. They examined trends in sulfur applications across multiple important crops in the US, including corn in the Midwest, sugarcane in Florida, and wine grapes in California. Their models of surface water sulfate export demonstrate that while areas like New England show declining trends in response to recovery from historic atmospheric deposition, sulfate export from agricultural areas is increasing.

“Although sulfur is applied to agricultural lands to improve the production and health of crops, it can have detrimental effects to agricultural soils and downstream waters, similar to what occurred in remote forest landscapes under acid rain,” concludes Charles Driscoll, a professor at Syracuse University and co-author of the study.

Agricultural Sulfur

Image retrieved from USDA

Driscoll says an example of the impacts of agricultural applications of sulfur is the enhanced formation of methylmercury in waters draining agricultural lands, such as the Everglades Agricultural Area in Florida. Methylmercury is a potent neurotoxin which accumulates in food chains leading to high concentrations in fish and increasing exposure of mercury to humans and wildlife that consume these fish.

The researchers predict that increasing trends will continue in many croplands around the world, including places like China and India that are still working to regulate fossil fuel emissions.

To date, much research has focused on understanding and regulating nitrogen and phosphorus fertilizers, which can cause eutrophication, fish kills, and harmful algal blooms downstream of agricultural areas.

Final Thoughts

Hinckley and Driscoll say it is time for the research community to apply lessons obtained from investigations into the effects of nitrogen and phosphorus fertilizers to studies involving the implications of high sulfur use in agriculture. Further inquiry, the researchers continue, must seek not only to document its environmental and human health effects but also to collaborate with farmers to investigate how to optimize sulfur use.

“Sulfur in agriculture is not going away,” said Hinckley, “Yet there is an opportunity to bring science and practice together to create viable solutions that protect long-term environmental, economic, and human health goals.”

 
 
Appreciate CleanTechnica’s originality? Consider becoming a CleanTechnica Member, Supporter, Technician, or Ambassador — or a patron on Patreon.
 
Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.

New Podcast: Cruise Talks Autonomous Driving Tech, Regulations, & Auto Design

New Podcast: Battery Mineral Mining Policies & Regional Trends

Written By

Carolyn Fortuna (they, them), Ph.D., is a writer, researcher, and educator with a lifelong dedication to ecojustice. She's won awards from the Anti-Defamation League, The International Literacy Association, and The Leavy Foundation. As part of her portfolio divestment, she purchased 5 shares of Tesla stock. Please follow her on Twitter and Facebook.

Comments

#1 most loved electric vehicle, solar energy, and battery news & analysis site in the world.

 

Support our work today!

Advertisement

Power CleanTechnica: $3/Month

Tesla News Solar News EV News Data Reports

Advertisement

EV Sales Charts, Graphs, & Stats

Advertisement

Our Electric Car Driver Report

30 Electric Car Benefits

Tesla Model 3 Video

Renewable Energy 101 In Depth

solar power facts

Tesla News

EV Reviews

Home Efficiency

You May Also Like

Clean Power

By the end of this century, global climate change may impact the wind resources in many regions of the Northern Hemisphere, decreasing hotspots in...

Air Quality

A new study in Nature Geoscience, led by Richard Zeebe of the University of Hawaii, looked at an anomalous time period called the Palaeocene-Eocene Thermal Maximum,...

Air Quality

Somebody call Donald Trump — Chinese pollution has joined the long list of illegal immigrants making its way across the seas and into America....

Clean Power

Originally published on The Lenz Blog by Karl-Friedrich Lenz Says this article at Nature Geoscience. Their numbers: If the contribution from wind turbines and solar...

Copyright © 2021 CleanTechnica. The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by and do not necessarily represent the views of CleanTechnica, its owners, sponsors, affiliates, or subsidiaries.