{"id":206148,"date":"2023-10-31T09:07:43","date_gmt":"2023-10-31T13:07:43","guid":{"rendered":"https:\/\/today.uconn.edu\/?p=206148"},"modified":"2023-10-31T09:46:10","modified_gmt":"2023-10-31T13:46:10","slug":"humans-are-disrupting-natural-salt-cycle-on-a-global-scale-new-study-shows","status":"publish","type":"post","link":"https:\/\/today.uconn.edu\/2023\/10\/humans-are-disrupting-natural-salt-cycle-on-a-global-scale-new-study-shows\/","title":{"rendered":"Humans Are Disrupting Natural \u2018Salt Cycle\u2019 on a Global Scale, New Study Shows"},"content":{"rendered":"

The planet\u2019s demand for salt comes at a cost to the environment and human health, according to a new scientific review published in the journal Nature Reviews Earth & Environment<\/a>. The paper reveals that human activities are making Earth\u2019s air, soil, and freshwater saltier, which could pose an \u201cexistential threat\u201d if current trends continue.<\/p>\n

Geologic and hydrologic processes bring salts to Earth\u2019s surface over time, but human activities such as mining and land development are rapidly accelerating the natural \u201csalt cycle.\u201d Agriculture, construction, water and road treatment, and other industrial activities can also intensify salinization, which harms biodiversity and makes drinking water unsafe in extreme cases.<\/p>\n

\u201cIf you think of the planet as a living organism, when you accumulate so much salt it could affect the functioning of vital organs or ecosystems,\u201d says lead author and University of Maryland Geology Professor Sujay Kaushal. \u201cRemoving salt from water is energy intensive and expensive, and the brine byproduct you end up with is saltier than ocean water and can\u2019t be easily disposed of.\u201d<\/p>\n

The researchers describe these disturbances as an \u201canthropogenic salt cycle,\u201d establishing for the first time that humans affect the concentration and cycling of salt on a global, interconnected scale.<\/p>\n

\u201cTwenty years ago, all we had were case studies. We could say surface waters were salty in New York or in Baltimore\u2019s drinking water supply,\u201d says study co-author Gene Likens, Distinguished Research Professor in UConn\u2019s Department of Ecology and Evolutionary Biology and Emeritus at the Cary Institute of Ecosystem Studies. \u201cWe now show that it\u2019s a cycle — from the deep Earth to the atmosphere — that\u2019s been significantly perturbed by human activities.\u201d<\/p>\n

The new study considers a variety of salt ions that are found underground and in surface water. Salts are compounds with positively charged cations and negatively charged anions, with some of the most abundant ones being calcium, magnesium, potassium, and sulfate ions.<\/p>\n

When dislodged in higher doses, these ions can cause environmental problems. The researchers show that human-caused salinization affected approximately 2.5 billion acres of soil around the world\u2014an area about the size of the United States. Salt ions also increased in streams and rivers over the last 50 years, coinciding with an increase in the global use and production of salts.<\/p>\n

Salt has even infiltrated the air. In some regions, lakes are drying up and sending plumes of saline dust into the atmosphere. In areas that experience snow, road salts can become aerosolized, creating sodium and chloride particulate matter.<\/p>\n

Salinization is also associated with \u201ccascading\u201d effects. For example, saline dust can accelerate the melting of snow, which can harm communities — particularly in the western United States — that rely on snow for their water supply. Because of their structure, salt ions can bind to contaminants in soils and sediments, forming \u201cchemical cocktails<\/a>\u201d that circulate in the environment and have detrimental effects.<\/p>\n

Road salts have an outsized impact in the U.S., which churns out 44 billion pounds of the deicing agent each year. Road salts represented 44% of U.S. salt consumption between 2013 and 2017, and they account for 13.9% of the total dissolved solids that enter streams across the country. This can cause a \u201csubstantial\u201d concentration of salt in watersheds, according to Kaushal and his co-authors.<\/p>\n

To prevent U.S. waterways from being inundated with salt in the coming years, Kaushal recommends policies that limit road salts or encourage alternatives. Washington, D.C., and several other U.S. cities have started treating frigid roads with beet juice, which has the same effect but contains significantly less salt.<\/p>\n

The study\u2019s authors also call for the creation of a \u201cplanetary boundary for safe and sustainable salt use\u201d in much the same way that carbon dioxide levels are associated with a planetary boundary to limit climate change. Kaushal says that while it\u2019s theoretically possible to regulate and control salt levels, it comes with unique challenges.<\/p>\n

\u201cThis is a very complex issue because salt is not considered a primary drinking water contaminant in the U.S., so to regulate it would be a big undertaking,\u201d Kaushal says. \u201cBut do I think it\u2019s a substance that is increasing in the environment to harmful levels? Yes.\u201d<\/p>\n

And like so many other environmental concerns, Likens stresses that now is the time to take action.<\/p>\n

 <\/p>\n

This research was supported by the National Science Foundation (Award Nos. GCR 2021089 and 2021015), Maryland Sea Grant (Award No. SA75281870W) and the Washington Metropolitan Council of Governments (Contract No. 21-001). This article does not necessarily reflect the views of these organizations.<\/em><\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

The influx of salt in streams and rivers is an \u2018existential threat,\u2019 according to researchers from UConn and the University of Maryland\u00a0<\/p>\n","protected":false},"author":58,"featured_media":206382,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_crdt_document":"","wds_primary_category":0,"wds_primary_series":0,"wds_primary_attribution":0,"footnotes":""},"categories":[2226,2460,2387,2235],"tags":[],"magazine-issues":[],"coauthors":[117],"class_list":["post-206148","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-clas","category-faculty","category-sustainability","category-today-homepage"],"pp_statuses_selecting_workflow":false,"pp_workflow_action":"current","pp_status_selection":"publish","acf":[],"publishpress_future_action":{"enabled":false,"date":"2026-04-23 15:35:52","action":"change-status","newStatus":"draft","terms":[],"taxonomy":"category","extraData":[]},"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts\/206148","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/users\/58"}],"replies":[{"embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/comments?post=206148"}],"version-history":[{"count":5,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts\/206148\/revisions"}],"predecessor-version":[{"id":206383,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/posts\/206148\/revisions\/206383"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/media\/206382"}],"wp:attachment":[{"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/media?parent=206148"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/categories?post=206148"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/tags?post=206148"},{"taxonomy":"magazine-issue","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/magazine-issues?post=206148"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/today.uconn.edu\/wp-rest\/wp\/v2\/coauthors?post=206148"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}