ESRM test 2
Forests

type of biome

 

Forest Area by region
Europe –
historically was almost entirely deforested, is actually increasing the amount of forested land
 
Africa & South America
primary reason for this loss is the clearing of land for agricultural land
 
Asia & America(s)
primary reason for this loss is urbanization.
 

Deforestation in Costa Rica

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Since 1940 
 the rate of deforestation & the change in the nature of the forests has been very dramatic

Forest Products

Most direct use – Wood

 

 

without involving destruction:

 

Latex extraction 

 

latex being extracted from rubber trees. 
 
Collecting nuts/fruits & raking foliage 
for animal bedding and fuel.

 

Wood Consumption

Outranks the use of most other natural resources

 

3.7 billion metric tons of wood that are consumed each year is more than steel and plastic consumption put together (more than 1/2 for Firewood) 
 
Developed countries produce less than half of all "industrial" wood, but account for 80% of wood consumption
 
Demand for wood: Estimated to double in 25yrs 
(twice the current availability) 
*particularly negative on impact poorer countries.
 
25% of world’s forests = managed for wood production ;

;

;

Monoculture Forestry

;

(aka Plantation Forestry);

type of reforestation; – only one species grown

;

example: Brazil

2% of forests (monoculture) produces approx. 50% of demanded product

;

;

*Criticized for extracting wood from native land (drastically less efficient);

Intensive Forestry

;

;

more efficient

;

Ideal: Sustainable Efficiency

;

;

;

protects natural land;

still producing demand but effieciently

;

;

Causes of Tropical Deforestation

;

Logging for valuable hardwoods (Mahogany)

;

Clearing land (Cattle ranch ; exported crops)

ie: bananas ; pineapples;

Slash and Burn Agriculture

burning of vegetation to release natural resources which assist growth of farm productivity;

(worked with low population)

;

Now the amount of people using land rises, so Slash and Burn could lead to deforestation

;

Forest Cutting

Major problem : changing area to non-forest for people

;

Destruction of habitat : leads to increased soil erosion from rain (namely tropical rainforest)

;

Waste of resources : could have been valuable exported somewhere instead of burned

;

;

Biggest Dietary Problem in the Richest Countries

Too much Poor-quality food

(issue in malnutrition)

;

Greatest Threats to ;Food Security;

;

(ability to obtain enough food daily)

;

Poverty

;

Lack of Social Status;

;

;

;

Statistics of Malnutrition

55% of the 12 million child deaths(per year)

;

;

More than 800 million (200million = children) are chronically undernourished

– receive ; 90% minimum caloric intake

;

Most Hungry: East/South Asia

also in Africa:; Tanzania ; Ehiopia

;

;;

;

;

Famines

Large-scale food shortages

;

Massive Starvation

;

Social Disruption

;

Economic Chaos;

Causes of Famines

;;; ;

Economic

;-price gouging

-landlessness

;

Environmental

-drought

-insects

-natural disasters

;

Political

-war

-oppression using famine as weapon

Malnourishment

Nutritional imbalance caused by:

– a lack of specific dietary components

or;

– inability to utilize essential nutrients

;

;

;

;

;

Nutrition Deficiencies

Iron deficiency (India)

anemia. (little oxygen in blood)

affects physical and mental development;

– most common dietary deficiency in world

most extreme in India

;

;Iodine Deficiency

– hyperthyroidism / goiter

;

Protein Deficiency:

Kwashioker;

-inflated belly disease occuring from lack of protein

;

Marasmus

;wasting away; sunken eyes, shriveledness, extreme thinness

;

;

Obesity

Most common dietary problem in Wealthy Countries

;

US:

61% adults

;

Russia:

54% adults

;

United Kingdom:

51% adults

;

Germany:

50% adults;

Major Crops

THREE

rice, corn, wheat

;

these 3 produce ; 50% world’s food

 

 

Vitamin A deficiency

Rice

 

this deficiency in poor countries causes blindness and a million child deaths each year

 

Genetic engineering – Europe

found "cure" in daffodils 

 

Animal Protein

 

Milk, Meat, Seafood

 

provides smaller amount of world food supply

 

90% grain produced is used to feed animals for Milk and Meat, but 20% of world consume 80% of meat/milk

 

 

Seafood

important source of protein

 

overharvesting / habitat destruction has resulted

 

Southeast Asia – destruction of wetlands for shrimp dependency

 

 

Environmental Issues Raising cattle

 

 

Loss of food from feeding cattle

 

Feedlots: 

Manure

produces methane

 

Scrap meat in food: Cannibalism

– spread of Prions (proteins which lead to neurological disease and spreading of TSE

leading to TSE or Mad Cow Disease 

 

Soil

Complete Mixture of:

*Weathered minerals *partially decomposed organic matter and a  *host of living organisms

 

Non-renewable resource

 

Complex living substance

20,000 types of soil

 

topsoil = most fertile part of the soil 

 rate lost > rate to replace

Land Resources

 

Average of 0.7 acres of cropland per person

 in 25 years estimated to be 0.42acres/person

 

land conversion = ecological trade off

refuges/reserves/etc 

 

Erosion

Most serious threat to soil degradation

-topsoil removed & transported elsewhere

reduces crop production by 1% each year

 

Natural Process

gravity,wind,water

 

 

Mechanics of Erosion

 Wind and Water

 

1) Sheet Erosion

Thin, uniform layer of soil removed

* 2) Rill Erosion *

                                    most common                                        small rivulets of water cut small channels into soil

3) Gully Erosion

Rills enlarge and forme small stream (torrent) and moves water deeper into the profile.  These channels are too large to remove through tillage

4) Streambank Erosion

Washing away the soil from an established stream bank

 

US and Canada have high erosion rates

 

 

 

 

Row Crops

leave soil exposed to wind (erosion)

 

intensive farming practice

**US and Canada 

 

 

Water

important agricultural resource

 

Huge costs – irrigation

80% water drawn never reaches intended destination

 

Extremely important in Northwest (apples) 

 

 

Fertilizer

important and Limited agricultural resource

 

Over-fertilization can harm or pollute

 

Three essential elements:

Nitrogen

Phosphorous

Potassium

 

 

Pesticides

90% never reach target  area

 

Precision agriculture

exciting new area of research

 

Crops w/o pesticides have lower yield, but also lower costs and eco damage 

Genetic Engineering

 

Splicing of a gene

from one organism into the gene of another

produces a GMO aka transgenic

 

GMOs Currently:

1/3 soy beans & corn 

60% all processed foods

 

increase costs could hurt small farmers 

 

Sustainable agriculture

 

"Regenerative Farming"

*Soil is essential

 

Goal: Produce food and fiber  w/o destructive agricultural processes

 

 

Soil Conservation

Important elements in conservation: 

Land management

Ground Cover

Climate

Soil Type

Tillage Systems 

 

*Dependent on maintaining groundcover

 

 

Managing Topography

Contour

plowing/planting with contour across slope

slows water flow

 

Strip-farming

planting different crops in alternating strips along the contours

 

Terracing

Shaping land to create level shelves

also with contour to hold water

 

*Also planting perennials (live>2years) 

Examples of Terracing

1960 famine China – Great Leap Forward

-plowed terraces

*no longer held water

 

food productivity didn’t restablize until terraces were; rebuilt

;

;

;

;

;

Most important Factor of;

Long-term Sustainable Agriculture

Keeping area vegetative

;;

(bare soil has higher erosion rates)

;

**Also need water availability

;

;

;

Reduced tillage methods

;

one of the greatest advances in

sustainable agriculture

;

dead vegetation is left on ground

acts as mulch

;

Reduces:

efforts of plowing

runoff (soil erosion)

;

;

;

;

Methods to reduce Bare Ground Erosion

Ground Cover

holds ; protects soil

ie: Alfalfa and clover fix nitrogen in soil

can be harvested for hay;

;ie: Mulching – can prevent erosion and insulate plants

;

Reduced Tillage:requires more pesticides

1) Minimum Tillage – reduces #times soil is turned;

chisel plow/ridge tilling

2) Conserv-tilling – sharp blade ;Coulter;

very little soil disruption;

3) No-tilling – drilled directly through mulch/ground cover;

;

;

;

;

;

Environmental Health Hazards

;

Involve Introduction of pollutants to:

Air, water, soil, ; food

;

**Air pollution has received much attention

-US Clean Air Act (decent job);

Health

state of well-being

physical, mental, social;

;

;

WHO
World Health Organization
Disease

deleterious change in the bodies condition

therefore cannot deal with some

environmental factor(s)

;

;

;

;

;

Morbidity

presence of illness

(in a population);

Mortality

presence of death

(in a population);

Leading causes of Mortality

#1 Worldwide:

Cardiovascular disease

-failure of heart to move blood through body;

;

Others:

*Cancer(s)

*AIDS

*Malaria

*Diarrhea

(among infants);

;

outbreaks of lethal infectious diseases

;

Ebola (Africa)

Buruli Ulcer (W.Africa)

West Nile

;

Factor that contribute to the

Spread of Contagious Disease

;

;

High population densities

-easier to move from person to person

;

Isolated Groups

-haven’t developed basic immunities to othe diseases
 -native americans

 

Environmental Change

global warming

 

Speed of travel

stress decreases resistance

travel allows disease to pass geographical barriers

 

Contamination of Food & Water 

 

 

 

 

 

Toxicology
Antibiotic & Pesticide Resistance

Penicillin

not as effective anymore 

 

Disease-causing protozoa 

*Malaria

now resistant to most antibiotics

 

Pesticide Resistance:

Malaria-carrying mosquitos

resistance developed against pesticides

 

 

Immune System depressants

PCBs

chemicals that affect immune system

 -reduce ability to fight disease

 

Teratogens

Hazardous chemical substance

 

cause mutations (affecting fetus)

ie: alcohol

Fetal Alcohol Syndrome

 

Carcinogens

substances that cause/aggravate cancer

 

US Top 3 Toxic & Hazardous substances

1) Arsenic

2) Lead

weights in fishing lures 

3) Mercury 

 

Risk Assessment

Study of Toxins

how they may harm humans/organisms 

Bioaccumulation

dilute toxins in the environment

-can reach dangerous levels inside cells & tissues

 

 

biomagnification

Effects of toxins

*seen through food web

 

small concentration of toxins increase as we move up through the food chain

ex – DDT and the American Bald Eagle 

 

 

DDT

LD 50 Factor (lethal dose)

measures toxicity of substance

lethal = 50% population dies

 

DDT’s LD 50 = 50mg/kg

*wont be immediate lethal impact, but we can see from historical evidence DDT effected humans;

;

Measuring Toxicity

;

Animal Testing

*can be quite inhumane

*can be unreasonable to compare

-animals ; humans have different immunities;

;*can be time consuming

– toxic effects can take years to appear;

;

Dose/Response Curve

Y-axis

#individuals first responding

;

X-axis

Dose;

;

;

Bell shaped;

Acute Effect

;

immediate health effect

caused by single exposure to toxin

;

Can be reversible

;

ie: You swallow Rat Poison but you’re okay 

Chronic Effect

long lasting or permanent effect

caused by:

1) single exposure to very toxic substance

2) continuous or repeated sub lethal exposure to a toxin 

Risk

Probability of

Harm x Exposure

 

*Biggest daily Risk = Driving

 

Risks change with perception

-therefore difficult to measure 

Main components of Earth

Earth’s Lower Atmosphere:;

Nitrogen – 78%

Oxygen – 21%

Argon – ;1%

;

*Carbon Dioxide extremely important, but low concentration

;

;

Earth’s Zones

Troposphere

Humans live

Stratosphere

Ozone Layer

Mesosphere

&

Thermosphere 

 

*divided by absorbtion of solar energy

 

 

Greenhouse Effect

50% Sun’s energy reaches Earth

;

Energy absorbed by Earth’s surface:

-changed into lower quality heat energy which is re-emitted as infrared energy

*because of Cloud Cover,

– this infrared energy is reflected back to surface to repeat same step

*cause of greenhouse effect / warming

 

 

 

 

 

Hadley Cells

Vertical Convection Currents

 

 

Coriolis Effect
Clockwise & Counterclockwise wind movements
Milankovitch Cycles

causes variation in temperature

 

occurs because of shift in Earth’s tilt, change in orbit, and wobble along axis.

;

Kyoto Protocol

;

Treaty setting limits on greenhouse gases for individual nations

*Based on output before 1990;

Photochemical Oxidants

Secondary pollutants

;

reduce local air quality

Sulfur Dioxide
Colorless gas that harms both plants and animals
Water Table
top layer of Zone of Saturation
Watershed
All land drained by stream or river
Primary Treatment

physically separates large solids from waste stream

(sewage treatment);

Secondary Treatment

(sewage treatment)

aerobic bacteria breakdown dissolved

organic compounds;

Tertiary Treatment

(sewage treatment)

removal of plan nutrients

(such as nitrates and phosphates);

from the secondary effluent

(chemicals, or natural wetlands);

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