Our sources of freshwater are being invaded by salt; we are paying the price

Salt and brine is applied to roads, parking lots, and sidewalks in winter to help melt ice and snow … and then washes off into streams, rivers, and lakes.  Burning coal and other fossil fuels in power plants creates emissions which makes rain acidic–and then slowly dissolves rocks, soils, buildings, and roads releasing yet more salt into the environment.  The amount of concrete and asphalt used globally continues to expand … and slowly break down.  More and more salts get into freshwater streams and rivers.

The result?  “At least a third of the rivers and streams [in the United States] have gotten saltier in the past 25 years.”  “By 2100, more than half of them may contain at least 50% more salt than they used to.”  

The impact?  Think Flint, Michigan; a decision to take drinking water from a “saltier local river” resulted in the salt leaching lead from old pipes and putting it into the water supply causing a very dangerous and expensive tragedy.  “Nationwide, salts are crusting the insides of home boilers and the cooling tanks of power plants.  They are also coating the land where crops grow.  And they are stressing plants and animals in freshwater ecosystems, in some cases until they disappear.”

Too much salt flowing into our sources of freshwater reduces the amount of available drinking water and increases the amount of water too salty for irrigation use.  The saltiest freshwater areas in the U.S. are the northern Great Plains (due to mining and oil and gas extraction), the urban Northeast, and the Midwest (due to agriculture).

But, the arid Southwestern U.S. may see the largest increases in salt in the future due to expanding agricultural irrigation and less rainfall.  The economic cost of too much salt in the Southwest is already huge–$300 million annually in the Colorado River basin; $3.7 billion (as of 2014) in lost agricultural production in California alone.

All this, of course, is just the immediate impact on people.  The price being paid by plants, animals, and our ecosystems is and will be high.  “The natural streams that collect water across the landscape and carry it along to the rivers and lakes we get our drinking water from are like a neural network connecting us to nature.”  “If they are unhealthy, sooner or later we’ll pay the price.”

Read the article (Tim Vernimmen, Scientific American, December 6, 2018).

For more information about the impacts of salinity, search the Science Primary Literature Database and the Headline Science Database.

Guns are the second-leading cause of death for children in the United States

For the period 2006-2016, guns were the second-leading cause of death for children (1-18 years of age) in the United States (according to statistics compiled by the Centers for Disease Control and Prevention).  Gun violence deaths surpassed deaths from cancer and trailed only deaths due to motor vehicle crashes.  Of the gun violence deaths, nearly 63% were homicides, 31% were suicides.

Research that could help track, analyze, and contribute toward solutions for gun violence has been hobbled by U.S. Congressional action in 1996 that prevented the “CDC—the government’s lead injury prevention agency—from spending money ‘to advocate or promote gun control.’  That law was widely interpreted as banning any CDC studies that probe firearm violence or how to prevent it.”

This may be changing.  The Firearm Safety Among Children and Teens (FACTS) Consortium has received “the largest firearm research grant that the U.S. National Institutes of Health has awarded in at least 30 years” ($4.9 million).   The grant is a 5-year project “to build capacity for researching firearm injuries in children.”   The grant is unique in gun violence research in the last 20 years in the United States in that “this is the first time that an award has been made not just to do a project, but to set up an infrastructure that would allow a lot of projects to be done.”

The politics in the United States about guns and gun violence and the reluctance of decision makers to change the status quo have contributed to these thousands of deaths.  The FACTS project could be/may be a fresh start–to search for common ground among all involved parties.

“We are not having any conversations here that are an ‘us and them’ narrative.”   “We are about reducing kids dying.”

(Meredith Wadman, Science, December 6, 2018).

For more information about gun violence and public health issues, search the Science Primary Literature Database and the Headline Science Database.




Increasing frequency of drought and decreasing yields for soybeans

Soybeans are one of the major food crops globally–along with corn, rice, and wheat.  The midwestern United States (particularly Iowa, Illinois, Minnesota, Nebraska, and Indiana) may be the primary production area for soybeans on the planet.

Rising carbon dioxide (CO2) concentrations in the atmosphere have many negative climate change impacts.  However, a long-held view (from research since at least 1997) has been that elevated CO2 may actually enhance production/yields in plants like soybeans–from the CO2 fertilization effect (CFE).  In fact, research had indicated that the CFE was expected in many cases “to mitigate the effect of drought on crop productivity”, and offset crop losses due to drought and heat stress.”  This finding had led some to conclude that climate change is not so bad for agriculture.

However, more recent research does not support this view–including research involving wheat and grasses as well as soybeans.  The yield stimulation effect of CO2 “may be far less than expected under future growing conditions that are characterized by concurrent increases in CO2 and drought intensity.”

Research by Jin, et al. (2018) found that multiple climate models project that the frequency of drought in the U.S. Midwest will increase to once every other year by 2050 (from once every 5 years at present).  “The increased frequency of drought conditions poses a formidable challenge to maintaining soybean yield progress, in part by diminishing the potential benefits of elevated CO2.”  And, the U.S. Midwest is a much more favorable environment for growing crops compared to drier regions like parts of Australia and Sub-Saharan Africa.  There, any anticipated benefits of increased CO2 are likely even less and climate change disruption to crop yields will likely be even more.

While genetic engineering of soybeans and a major shift to irrigation could help “stabilize soybean yield,” the challenges are formidable and diverse.

Will society accept more genetically-modified crops?  And, as droughts become more frequent and more intense, where would the extra water come from for greatly-expended irrigation?  What choices will we make between water for people and water for crops?  And, what about heat stress?  The research projects “a sharp decline” in soybean yields in the period 2071-2090 as a result of greater heat stress alone.

Greater heat, more frequent and intense droughts, rising CO2 levels happening all at the same time–all these factors point to plateaus and declines in major food crop yields globally within the lifetimes of us and our children.

(Kevin Engel, December 1, 2018)

For more information about the impacts of climate change on agriculture, search the Science Primary Literature Database and the Headline Science Database.