Research Poster 36 x 48 - A

1
19. Bedrock Composition, Soil Chemistry, and
Animal Health Global Case Studies in Applied
Medical Geology
Rachel Johnson
Swedish Moose
Abstract
Introduction
Kenyan Herbivores
Livestock
This poster examines relationships between
regional bedrock geology, soil composition, and
plant nutrient quality. Animals are affected by
changes in bedrock composition and attendant soil
mineralogy. Mineral deficiencies and poisonings
occur due to geochemical anomalies in a given
region. Mineral imbalances can also cause
diseases as the excessive uptake of one element
blocks absorption of other necessary nutrients.
Changes in soil moisture, organic matter content,
clay content, ph levels, and cation exchange
capacity affect bulk soil chemistry and hence
plant nutrient uptake. Plants in turn absorb
these elements and sicken foraging animals if
they do not contain the proper mineral balance.
Deficiencies are further exacerbated by droughts,
excessive snowfall, and temperature extremes that
restrict animal diets to less efficient food
sources. Case studies are presented to illustrate
bedrock-plant nutrient associations. Farmers have
experienced ruminants succumbing to molybdenosis
and copper deficiency. Molybdenum creates an
endocrine imbalance leading to weight loss,
lethargy, emaciation, and behavioral Disturbances.
Wild herbivores are most affected by excessive
or deficient mineral quantities in plants. For
example, Swedish moose commonly develop type-2
diabetes due to chronic molybdenosis and elevated
glucose levels. In Africa, animal migration
patterns follow the availability of plants that
contain essential trace elements that are endemic
to a particular geologic terrain.
Soils in southwestern Sweden are highly acidic.
Acidic soils cause plants to absorb more
molybdenum (Mo). Mo in turn blocks the absorption
of copper and cadmium in ruminants (Frank, 2003).
Copper deficiency causes a condition known as
mysterious moose disease and wasting disease
in moose. It is characterized by diarrhea, loss
of appetite, discoloration or loss of hair,
apathy, neurologic problems, hemorrhages,
gastrointestinal lesions, and dilated flabby
hearts in ruminants, see Figure 4 (Frank, 2003).
Symptoms dont all appear in the same animal.
This moose disease is molybdenosis which causes
copper deficiencies as molybdenum blocks the
absorption of copper. Copper deficiency leads to
glucose intolerance. Moose with molybdenosis were
also affected by diabetes due to long-term high
glucose levels (Frank, 2003).
Much of the native wildlife of Kenya resides in
national parks and wildlife reserves in order to
preserve them while using their old rangeland for
other purposes. Soil samples show that each
reserve is abundant in some nutrients, but
lacking in others (Maskall and Thornton, 1996).
Lac of migration prevents herbivores from
reaching more plentiful minerals. Arid conditions
also create layers of salt at the soil surface
(Maskall and Thornton, 1996). African elephants
rely on these sources of sodium as well as cave
salts in order to meet their nutritional needs
(Bowell et al., 1996), see Figures 1 and 2. The
reliance on confined reserves to provide the
nutritional needs of many animals is inadequate.
Competition for quality lands means that these
reserves are located on marginal quality land
(Maskall and Thornton, 1996).
Animals require the proper balance of trace
elements in their diets. Improper levels of these
elements leads to deficiencies or intoxications,
both of which can be fatal. Plants absorb the
elements in the local soil and wild herbivores
are most susceptible to geochemical anomalies
(Jones, 2005). Nutrient deficiencies are often
prevented by animal migrations. Habitat
destruction prevents migration and animals are
often restricted to reservations which do not
contain of the nutrients that they would have
received by migrating (Maskall and Thornton,
1996). In regions that are seeing an increasing
demand for agricultural lands the local animals
die from lack of food or suffer from mineral
deficiencies on reservations. Agriculture and
other activities cause changes to the local soil
conditions. Increases or decreases in the total
amount of trace elements, or changes in the
floras ability to absorb them leads to regional
diseases in animals.
Latin American cattle suffer from calcium and
phosphorus deficiency. This causes subnormal
growth, low reproduction, and pica the regions
pigs suffer from poor growth, gait disturbances,
lameness, bone deformation, and vertebrae
fractures (Jones, 2005). Iodine deficiency is
common in mountainous regions (inner Siberia,
Africa, and South America Himalayas, Alps,
Pyrenees, Andes) and places where excessive
leeching has occurred. This condition is known as
goiter and causes enlargement of the thyroid
gland (Jones, 2005). It causes newborn lambs and
calves to die of suffocation soon after birth due
to increased pressure on the trachea by the
thyroid. (Jones, 2005). Adult ruminants dont
produce sufficient thyroid hormones and this
leads to lethargy, increased fat deposits, and
impaired reproduction in the form of irregular or
suppressed estrous cycles (Jones, 2005). Arsenic
poisoning is common in Bangladesh, Argentina,
Mexico, and the US. It is used in herbicides and
pesticides and remains in the soil (Jones, 2005).
Exposed cattle suffer from diarrhea, weight loss,
eye inflammation, respiratory infection, changes
in hair coat, and is lethal in acute cases
(Jones, 2005)
Soil Properties
Conclusions
Soil properties that influence the amount of
trace elements that are absorbed by plants
include the total amount of the element, soil pH,
and moisture content. The parent bedrock material
of the soil is the main source of elements in the
soil, but organic decomposition also plays a role
(Maskall and Thornton, 1996). Soil pH is a
negative logarithm that represents the number of
hydrogen ions in the soil and is related to
sodium and calcium concentrations (Maskall and
Thornton, 1996). Different plant species grow in
acidic and alkaline soils. Soil pH also
determines how much of an element a plant can
absorb. Moisture content is determined by
precipitation and evapotranspiration rates. When
there is more precipitation leeching occurs
causing soil to become more acidic. pH determines
how much of the surrounding trace elements can be
absorbed by the plants.
Anthropogenic activity has caused soils to
change. Irrigation increases leeching. Herbicides
and pesticides add trace elements that are meant
to hurt unwanted competitors, but also poison
livestock. We have also moved animals to new
lands with different nutrient balances and
prevented migration, prohibiting animals from
reaching their ideal food sources. Increased
production needs will create more problems for
animals. As long as people continue to modify
landscapes animals that have relied on the way
the land previously was will starve or suffer
from malnutrition.
Figure 1. African Elephant scraping a cave for
salts (Bowell et al., 1996).
Figure 2. Elephant with a worn tusk, most likely
from digging rocks and soil (Bowell et al., 1996)
References
Bowell, R., Warren, A., Redmond, I. (1996)
Formation of cave salts and utilization by
elephants in the Mount Elgon region, Kenya
Geological Society, London, Special Publications,
v. 113 p. 63-79. Fordyce, F., Masara, D.,
Appleton, J. (1996) Stream Sediment, soil and
forage chemistry as indicators of cattle mineral
status in northeast Zimbabwe  British Geological
Survey, Overseas Geology Series, no.
WC/94/3. Frank, A. (2003) Molybdenosis Leading to
Type 2 Diabetes Mellitus in Swedish Moose, in
geology and health closing the gap. By Skinner,
H., Berger, A. p. 79-81. Jones, B. (2005) Animals
and Medical Geology in Essentials of Medical
Geology , edited by Selinus, O. p.
513-526. Maskall, J., Thornton, I. (1996) The
distribution and major elements in Kenyan soil
profiles and implications for wildlife nutrition
Geological Society, London, Special Publications,
v. 113, p. 47-62.
Figure 3. Thyroid glands from cattle. The middle
is a normal thyroid gland the others show growth
due to insufficient iodine intake (Jones, 2005).
Figure 4. Sheep wool discoloration caused by
molybdenosis (Jones, 2005)