SOIL POLLUTION

Clip Art: Soil Quality Institute

Objectives:

1)  Know different types of soil pollution
2)  Know best management practices BMP for combating soil pollution

What is soil pollution? Degrading soils leaving it less useful or less suitable for the _____________________________
Not all pollution always has to be toxic, mutagenic, or carcinogenic to humans.  In the case of ____________ or _____________
the overall quality of the environment is reduced

I. Types of Soil Pollution

1) Nitrates and Phosphates

One of the most common forms of soil pollution is ______________ and phosphate pollution leading to eutrophication.  Basically, eutrophication
is excessive nutrient enrichment of water bodies leading to explosive algae growth, decreases oxygen content, and fish die-off.  It is more important to
limit ____________________ rather than nitrates because of the principle of the limiting factor. Algae and cyanobacteria can fix nitrogen in sufficient
amounts from normal background levels of nitrogen; phosphorus, however, readily forms insoluble compounds and can act as a limiting factor on algae
growth.

Under anaerobic conditions microbes reduce nitrate ion to nitrite ion in large amounts; this effect is called methemoglobinemia.  The nitrite is absorbed
into the bloodstream where it robs the blood of hemoglobin.

2) Pesticides

Today, agriculture accounts for  1/3, 2/3, nearly all (circle one) of pesticide use.

Acceptable pesticides are
1) not be carcinogenic or _______________________
2) must be effective at killing the insect or fungal pest
3) have a ______________________ in the environment.

While DDT was a less toxic pesticide than many of the pesticides used today, it was extremely ____________________ as highlighted in Rachel
Carson's book, Silent Spring.

3) Heavy Metals

Examples of heavy metals include Cd, _______,  _______,  _______, Cr, and Cu.

Not only are heavy metal toxic but they do not _____________ and tend to bioaccumulate.  Once in the soil, heavy metals are difficult to remove.  Thus, if a
salmon ate 20 alewives, each with .1 g of Pb, the salmon would bioaccumulate 2 g of Pb.

Elements and their inorganic compounds may be absorbed on clay and organic matter surface as exchangeable ions, may be fixed in nonexchangeable
forms, or may be precipitated in the soil.

4) Salts

In the space below, diagram the salinization process

Salts cause land abandonment, lower water quality, and inhibited _________________ in lakes and ponds.

5) Manure and Food Waste

Disposal increases the BOD _____________________________ which is a measure of the amount of oxygen needed to decompose organic matter like
manure and food waste.

Every pound of meat produces around _____________ lbs of manure.

How is today's manure different from manure in the past?

1)
2)

6) Radioactive Elements

Sources include fallout dusts from nuclear testing, accidents like _________________, and natural soil sediments that are radioactive, that is soil
weathered from uranium deposits, or from sand, fill, or mortar used from these deposits. 

A decay product of uranium is radium which produces radon.  An EPA map reveals definite spatial trends for radon gas, although homes with elevated
levels of radon have been found throughout the state.

7) Sediments

1) __________________ effect
2) siltation of ______________________, reducing hydroelectric generation capacity and recreation quality
3) flooding by raising the bed of rivers

8) Airborne Pollutants

1) _____________ from denitrification and __________________ are potent greenhouse gases
2) dusts can transmit disease carrying bacteria across continents and interfere with the creation of rain.

II. Reducing Soil Pollution

Best Management Practices- List four to five management practices to reduce pollution deriving from soils

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