Over the past century, farming practices in the Midwest have led to increasing soil salinization. Excessive irrigation has caused salts to accumulate on soil surfaces, decreasing fertility. Other issues like overgrazing, wildfires, and lowering water tables further exacerbate the problem. Nearly 50 million acres of cropland and pasture are currently affected by high salt levels, rendering the soil unsuitable for agriculture. To sustainably manage soils into the future, improved practices are needed to prevent further salinization and degradation of these important agricultural regions.

1. Jesse Jones
Principle to Soil Science: Semester Paper
3/20/2015
Salinization of the Midwest
Over the past 100 years farming has been a main life line for our country economically and
culturally. In the United States, there have been large amounts of agricultural practices that have been
used on the soils of the Midwestern states in the last century. In this short time scale of an environmental
viewpoint of only 100 years,societies in these states have had to figure out how to mitigate for the
consequences seen through the large scale farming practices. The process of salinization within these soils
have been an ongoing issue for the farmers of the early 20th century to present. The process of this issue
will be described and explained through this paper. As well as a large scale study of the Colorado River
being saturated with the salts of the soils of the Midwestern state of Colorado. In the past we have been
greatly mistaken with thinking the proper care of the soils beneath our feet was in thought of water.
Farmers have been paying for this mistake and have been trying to find better ways to balancing out the
salts within the soils throughout all sorts of studies. Salinization as a whole isn’t completely direct with
the misunderstanding of the farming society, salinization can also be exploited through nature causes as
well.
The process of salinization is a concept at first is pretty hard to grasp. Many people misperceive
this issue of the soils being dried out and have evaporates showing up within the soil content. This is
actually not the case in this problem of salinization. The problem occurs when farms irrigate their land
with too much water and over time the water doesn’t infiltrate fully or in a timely manner and gets
evaporated and leaves evaporate behind. In lack of terms, these salts stand on the surface of the soil
profiles throughout the Midwest and pretty much dehydrate the nutrient rich soils to unfertile soils that are

2. too salty and in this matter create salt water which then is to potent for crops and other habitats to use for
food and hydration purposes. When this occurs the nutritional value of the soils breaks down over time
and the farmer of that area cannot use those agricultural fields for a very long time until the salinity levels
are low enough that the plants can use the water and other elements within the soils for a proper food
source. The greatest areas of salinization occur mostly throughout the Midwest due too there being large
amounts of time of being arid throughout the year. This dryness is a great factor for potential sodic soils
to form within the surface layer of the soil units. When there is extreme droughts the surface layer can
erode down into a clay based soil which can inhibit salinization to occur and crusting to form as well.
Throughout the mid-western states there have been a varied of overwhelming human impacts to
the soils. Impacts that can range from urbanization of big cities around the region, to a large amount of
farming practices like, over grazing of cattle and too much tilling of agricultural fields. There are natural
occur impacts as well, for example, natural brush fires that happen in this arid climate quite frequently.
Impacts have primarily come from the over excessive farming and tillage of the soils around the many
states in the Midwest. In the past century the soils of the Midwest have seen a lot of change and all
different types of weather elements as well as different farming practices being done to them. With the
temperature getting warmer as the years go on and the gusting of winds around the plains, intake of water
from farmers wells are sucking more water than the aquifers can handle which causes the water table to
drop significantly and brings risk to having aquifers running dry. According Michigan States own Bruno
Basso,“Already, there are regions in Texas and Kansas where farmers can’t pump enough water to meet
the demands of their crops (Basso 39).” When this starts to occur the water table will then drop and the
concentrations of salts will start to rise over time as the surface of the soil profiles. Being humans our
reaction is to keep watering and watering the soils so the roots wont dry up and the surrounding soils will
be able to give the crops the nutrients they truly need to grow. When this natural reaction occurs water is
then pumped from an aquifer that is already low and this water is unable to infiltrate the surface soil due
to the process called surface crusting. This process of infiltration is key to making food for these crops.

3. This crust layer will speed up the process of evaporation, which is bad because the water that was just
used to irrigate the farmer’s crops is then evaporated away leaving behind the sodium that was within the
water. The water being put on these agriculture fields which came from the aquifers below has rising
sodium content from the water table lowering. The process of percolation is being cut off and is not
playing its role of recharging the water table and the aquifers below. The start of this whole process
comes from the improper practices of farmers excessively tilling their soils and on top of that irrigating
these bare soils. Which then, dries up the soil surface and creates this crust and then this plays a role in
negating the natural process of infiltration and percolation of the water being put on these fields and
evaporates into a thin layer of sodium. According to Soils Quality a NRCS collaboration website, “A
surface crust is an indicator of poor infiltration, an unstable seedbed,and reduced air exchange between
the soil and atmosphere. It can also indicate that the soil has a high sodium content that increases soil
dispersion when it is wetted or irrigated (NRCS 1).” This is basically saying what we have been doing for
the past century was the wrong way to sustaining the soils of the Midwest. Over irrigation the last 100
years is starting to show signs of its use through many different variables in the environment. This is a
vital impact that is ongoing and is showing its consequences with the degradation of our soils through
salinization and the large amounts of water being put out on these fields around the Midwest.
There are other impacts that causes saline levels to rise in the Midwest. One by which comes
from the wicked forces of nature called, wild fires. These fires occur during the dry season which can
trigger immense amounts of drought and can spark vegetative fire throughout the lands. This is not good
because this natural process leads to lots of bare soil exposure. When this bare soil is exposed the rate of
salinity levels can increase at large amounts. This is due to the fact of these soils being covered by dense
prairie grasses and these soils were getting proper moisture and nutrients from the root structure of these
grasses above the soil layers. When these fire occur the nutrient content is stripped away from the soils
and in due time these soils will dry up quickly and saline evaporates will appear on the surface from the
extreme effects of the hot temperatures and winds whipping across these arid plains. These fires occur

4. from the water table receding from high irrigation rates and the decrease to precipitation during the
elongated periods of extreme dryness.
Another variable that needs to be taken into account is the practices of the other farming industry
of the Midwest and the horrific effect of overgrazing. These cattle farmers are coming to the same
problems of these crop farms only taking place within the pastures that these huge numbers of cattle head
are roaming. The proper practices of rotating pastures and splitting up herd cattle is not being taken into
consideration and in this case these farmers are seeing a decreasing soil quality every year and spikes in
salinity on their fields. As the cattle compacts the soils within the pasture the drying of the soils speeds up
exponentially. According to Hurburt Kelly, “The destruction of grazing land follows an all too familiar
sequence of events. Overgrazing by cattle reduces plant cover, eliminating the most desirable forage
species first. This opens land to undesirable weeds,brush, and tress and leads to increasing soil erosion
and lower soils fertility. The land becomes less and less productive (Kelly 19).” This is a prime example
of how overgrazing can increase the level of severity in degrading soils. The relationship of compaction
from the large counts of cattle going over the soils and the elements of high temperature and winds will
trigger the right mixture for unstable saline soils throughout the Midwest. According to NRCS’s
publication of The State of The Land, about 570 million acres of the contiguous United States have a
moderate to serve potential for soil and water salinity problems. At least 48 million acres of cropland and
pasture are currently affected (NRCS 10). This gives a great overview to the big picture on how much
land is used in farming of cattle in the Midwest and how much land is at stake if these farmers don’t
change their traditions. When the salinity levels reach a threshold of not being able to produce any type of
crop or grasses due to the high concentration of salts the soil is considered unfertile and will take long
periods of time before the soil can be used again for agricultural uses like grazing and growing crops. In
the years to come these impacts that are inhibiting salinization will be interesting to see if humans can
adapt to the problems and learn from the mistakes and change farming methods to sustaining great source
of fertile soils around the Midwestern.

5. One of the biggest bodies of water in the United States that is seeing some of the worst saline
levels is the Colorado River. Flowing through mountainous regions with very arid environments it’s a
body of water that has some of the highest concentrations of sodium due to the surrounding soils and
other geological variables. There is a case study that was done not too long ago that gives a good stand
point for where some of these drier western states along the Colorado River are heading in terms of soils
quality containing high amounts of soluble salts within them. This journal brings our attention to a
different angle to how these soils and geological structures truly become the culprits to saltiness of the
water table and larger bodies of water like the Colorado River. This study was done in 2009 which is very
resent to our knowledge in the environmental mindset. In understanding geological changes which occur
at a very slower rate and we should definitely should be taken into consideration since these geological
issues cannot be fix in the matter of a couple years. The outline to this writing is as so, anthropogenic
activities in the Colorado River basin (for example mining, farming, petroleum exploration, and urban
development) can greatly accelerate the release of constituents from these geologic materials, thus
increasing the salt load of nearby streams and rivers (Tuttle 1). This is an interesting statement to take into
consideration as we move forward in studying how to control these salinity levels throughout the
Midwestern states like Colorado. These human impacts which have developed over the past century have
caused salinity levels to rise in the soils beneath the feet of the societies in the states along the Colorado
River but as water flow there is always more places downstream that will be affected. Mexico has been in
communication the last thirty years due to the fact of huge amounts of sodium loads in the waters of the
Colorado River being brought down to the United States and Mexico border.
Within this study of the many watersheds and geological units in the state of Colorado the
number given from the journal were absolutely demoralizing to see for the future of this state and raises
many red flags to the farming industry and the societies around the area. For example, at least 33 million
people and 4 million acres of farmland throughout the United States depend on the water of the Colorado
River (Tuttle 1). This is a good point to be made with the detrimental impacts of salinization. With there

6. being 33 million people in the vicinity of the Colorado River there for means large amounts of
urbanization and farming to support these huge communities along the Colorado River. Throughout this
study there is a direct relationship between the anthropogenic activities these communities bring to the
soils and waterways of the Colorado River Basin. With the rise of human activities like farming for
example, there is a decrease in soil quality at the surface which starts a domino effect. With the rise in
sodium levels which in time will leach through the soils down into the bedrock and then goes straight to
the water table and out to the Colorado River Basin. With this cycle consistently happening over the last
century the salinity levels of the Colorado River have sky rocketed and have gotten so bad it has started to
effect international communities in the country of Mexico 30 years strong and after the Clean Water Act
of 1972 was past soon after one of the first state of the art desalinization plants were implemented on the
Colorado river at the United States and Mexico border.
This study along the Colorado River has a pretty interesting concept in methodology to tracing the levels
of sodium throughout nonpoint sources using trace methods in the various sites of study. Throughout the
study the major elements that were formed around the ground and the surface water were calcium,
magnesium, sodium, potassium, chloride, sulfate, and bicarbonate. These solutes are generally
conservative in water,although precipitation of calcite can occur and calcium and magnesium can be
absorbed during cation exchange. The one objective that appeared interesting throughout the study was
the use of tracers in the major geological sources of sodium to the Upper Colorado River. (Tuttle 2).
Using this type of method is helpful to understanding the process of salinization within the soils and water
table below. Reading through the article this study gained lots of information that uncovered levels of
evaporates at the surface and the concentrations from weathering material leading to the increase of
salinization levels. The latter results have important implications for health of human and organisms as
severalenvironments where acidification can occur in the animal’s lungs and stomach, plant root zones,
and amended soils (Tuttle 2). After getting the results through the methodology of using tracers the
concentration levels led to conclusions that the saline levels throughout the water and geologic features

7. were to be taken with caution due to high acidic levels and could potential cause human and animal health
issues.
As human beings we have played a significant role in the development of the soil erosion process
called salinization. The acceleration of this impact has been made through many farming practices like
lash and burning and over grazing which has led to the tragedy of the Dust Bowl of the 1930’s as well as
other natural effects like grass fires. With the aquifers and water tables on the decline and these soluble
salts on the raise, impacts are starting to form all over these farming communities due to salinization.
Looking to the future, have we come too far to look back and learn from these mistakes or is this a new
beginning to seeking out ways to overcome the degradation of these important soils that truly are the
blood line to these Midwestern communities and the life line to our country’s economy. Research
surveys like the one put together by Michele Tuttle along the Colorado River raises awareness and gives a
true setting for what environmentalist will have to face in order to sustain these soils for future
generations. Studies like this will give way to opening many eyes throughout the environmental soil
studies to understanding and figuring out what will need to be done to set forth sustainable habits for
farmers and to educate the people of these communities on where these generational soils are heading if
change doesn’t start now.

8. Work Cited
Basso, Bruno, Anthony Kendall, and David Hyndman. "The Future of Agriculture over the
Ogallala Aquifer: Solutions to Grow Crops More Efficiently with Limited Water - Basso - 2013 -
Earth's Future - Wiley Online Library." The Future of Agriculture over the Ogallala Aquifer:
Solutions to Grow Crops More Efficiently with Limited Water - Basso - 2013 - Earth's Future -
Wiley Online Library. Earth's Future. Web. 22 Apr. 2015.
<http://onlinelibrary.wiley.com/doi/10.1002/2013EF000107/full>.
Andrews, Susan, Michelle Wander, and Holli Kuykendall. "Indicators: Soil Crusts." Soil
Quality: For Environmental Health. NRCS East National Technology Support Center. Web. 22
Apr. 2015. <http://soilquality.org/indicators/soil_crusts.html>.
Tuttle, Michele L., and Richard I. Grauch. Salinization of the Upper Colorado River--
fingerprinting Geologic Salt Sources. 1st ed. Vol. 1. Reston: U.S. Geological Survey, 2009. 61-
62. Print.
Kelley, Hubert W. "How Soil Is Destroyed." Keeping the Land Alive: Soil Erosion--its Causes
and Cures. Vol. 50. Rome: Food and Agriculture Organization of the United Nations, 1983. 19.
Print.
"Protecting and Enhancing Agricultural Productivity." State of the Land. Vol. 1. Washington
DC: Natural Resources Conservation Service (NRCS), U.S. Dept. of Agriculture (USDA), 1997.
9-10. Print.