Nature Conservation Chapter 3.1

RECAP OF PREVIOUS LECTURE

PHYSICAL COMPONENTS

• Lithosphere – rocks and

soils

• Hydrosphere – water

• Atmosphere - air

Exponential growth of human

population began in the 1800s

Human population growth rate in percent

Human population growth issue

China & Mexico and India face more environment stress with

the highest population

Population growth rates are high in poor areas, whereas

resources consumption and well-being are low

Factors human population growth:

a. Migration : the relocation of humans

b. Developments

c. Innovation in agriculture increased food supply

Managing population growth

a. Family planning

b. Development and population – economic development,

education

ENVIRONMENTAL PROBLEMS

Environmental Problem: POLLUTION

What is pollution?

Where does it come from?

• Any addition to air, water, soil, or food that threatens the

health, survival, or activities of humans or other living

organisms

• The particular chemical or form of energy that causes such

harm is called pollutant

• Most pollutants are solid, liquid, or gaseous by-products or

wastes produced when resource is extracted, processed,

made into products, or used

• Pollution can also take the form of unwanted energy

emissions, such as excessive heat, noise or radiation

Environmental Problem: SOIL POLLUTION

Defined as the build-up in soils of persistent toxic

compounds, chemical, salts, radioactive materials, or

disease causing agents, which have adverse effects on

human, plant growth, and animal health

• The wars the hit the Earth are one of the immediate

causes of soil pollution

• Many countries found the necessity to improve their

living standards

• After the WWII (1945), may countries suffered from food

shortage and this facilitated the introduction of fertilizers

and other agricultural chemicals


Sources / Types of soil contamination

• Rupture of underground storage tanks (i.e. septic tanks,

etc.)

• Application of pesticides

• Percolation of contaminated surface water to subsurface

strata

• Oil and fuel dumping

• Leaching of wastes from landfills

• Direct discharge of industrial wastes to the soil


Examples

• Pesticides such as DDT

(dichlorodiphenyltrichloroethane), a potent nerve poison

in insect was widely used to combat fever and malaria

• It was later used to control and/or eradicate disease

carrying and crop eating insects

• Effects: DDT prevents the shelling of bird eggs and in

human causes health threats


Examples

• Arsenic, used by the glass industries is also a pollutant

(very poisonous)

• Arsenic are used to eliminate the green color caused

by impurities of iron compounds

• Other examples: heavy metals such as lead, iron,

chromium, copper, zinc – although small traces are

necessary for plant growth, high concentrations of

these compounds renders the land unsuitable for plant

growth


Impacts of Soil Pollution

• Radical chemistry changes, manifested in the alteration

of metabolism of endemic microorganisms and

arthropods resident in a given soil environment

• Disruption of the food chain

• Alter plant metabolism, reducing crop yields

• More economic losses

Environmental Problem: WATER POLLUTION

Contamination of water bodies such as lakes, rivers, oceans,

and ground water by human activities


Categories of Water Pollution

Point source pollution – contaminants that enter a waterway

through a discrete conveyance, such as ditch or pipe (sewerage

treatment plant, factory, etc.)

Non-point source pollution – diffuse contamination that does not

originate from a single discrete source. It is often accumulative

effect of small amounts of contaminants gathered from a large area

Ground water pollution – groundwater contamination;

contamination of aquifers

Example: spill of chemical contamination of soil, located away from

a surface water body, may not necessarily create point source or

non-point source pollution, but nonetheless, may contaminate the

aquifer below


Causes of Water Pollution

Pathogens

• Coliform bacteria

• Cryptosporidium parvum

• Giardia lamblia

• Salmonella

• Novovirus and other viruses

• Parasitic worms (helminths)



Chemicals and other contaminants

• Detergents

• Disinfection by-products found in chemically disinfected

drinking water, such as chloroform

• Food processing waste (i.e. fats and greases)

• Insecticides and herbicides

• Petroleum hydrocarbons (i.e. gasoline, diesel fuel, jet fuels,

fuel oil)

• Lubricants (motor oil)

• Chemical waste industrial by-products



Chemicals and other contaminants

• Fuel combustion by-products

• Tree and bush debris from logging operations

• Volatile organic compounds (industrial solvents, chlorinated

solvents

• Acidity caused by industrial discharges (sulfur dioxide from

power plants)

• Ammonia from food processing waste

• Chemical waste industrial by-products

• Fertilizers containing nitrates and phosphates

• Heavy metals

• Silt (sediment) in runoff from construction sites, logging,

slash and burn practices or land clearing sites



Macroscopic pollution

• Large visible items polluting waters (marine debris)

• Trash (i.e. paper, plastic, food waste)

• Nurdles (small ubiquitous waterborne pellets)

• shipwrecks



Thermal pollution

• Rise or fall in the temperature of a natural body of water

caused by human influence

• Common cause: use of water as a coolant by power plants

and industrial manufacturers

• Also caused by the release of very cold water from the

base of reservoirs into warm rivers


Impacts of Water Pollution

• Unsuitable for human consumption

• Can cause diseases (i.e. cholera, typhoid, gastroenteritis,

diarrhea, parasitic infection)

• Corrosion potential of water

• Problematic for certain irrigated crops, reduced crop

yields

• Affects biodiversity (i.e. aquatic organisms, birds feeding

on aquatic animals)

• Blockage of drains, overflowing sewerage systems

Environmental Problem: AIR POLLUTION

Introduction of chemicals, particulate matter, or biological

materials that cause harm or discomfort to humans or other living

organisms, or damages natural atmosphere, into the atmosphere


Most common air pollutants in the air

Sulfur oxides (SOx) – e.g. sulfur dioxide (SO2-; SO2)

Anthropogenic sources: industrial processes,

combustion of coal and petroleum

Natural sources: volcanic eruption

Effects: combined with NO2 will cause acid rain

(H2SO4)

Nitrogen oxides (NOx) – e.g. nitrogen dioxide (NO2);

the most prominent air pollutant; reddish-brown toxic

gas that has a sharp, biting odor

Anthropogenic sources: high temperature

combustion



Carbon dioxide (CO2) – (vital to living organisms)

Anthropogenic sources: combustion

Natural sources: plants and animals (natural gas in

the atmosphere)

Carbon monoxide (CO)

colourless, odourless, non-irritating but very

poisonous gas

Anthropogenic sources: combustion

Natural sources: by-products of plant’s chemical

processes



Volatile organic compounds – e.g. methane (CH4),

benzene, tuolene, xylene

Anthropogenic sources: combustion, industrial

processes

Natural sources: plants and animals

Chlorofluorocarbons (CFCs)

harmfil to the ozone layer

Anthropogenic sources: industries (aerosol

propellants, cleaning solvents; refrigerants; plastic

blowing agents, etc.)



Ammonia – NH3-; gas with a pungent odor

Anthropogenic sources: pharmaceutical industries

Natural sources: agricultural processes (use of

fertilizers)


Impacts of Air Pollution

Human health - breathing/respiratory diseases

(emphysema, bronchitis), inflammation of epithelial

linings, long-term exposure causes cancer, asthma,

respiratory infections, pulmonary disease, cardiovascular

disease

Environmental – global warming and climate change

EXAMPLE OF WORLD’S WORST CASE INCIDENT/DISASTER

THE GREAT SMOG OF 1952 - December 1952, London

• To cope up with the very cold winter, Londoners burned more coal than usual

• The resulting air pollution was trapped by the inversion layer formed by the dense

mass of cold air, thereby increasing the concentrations of pollutants dramatically

• Fog was so thick, driving became almost impossible

• Decreased visibility resulted to more crimes

• During the 4-day period of fog, at least 4,000 died as a direct result of the weather

EXAMPLE OF WORLD’S WORST CASE INCIDENT/DISASTER

MALAYSIA’S HAZE PROBLEM 1997-98

• Cause: Forest fire in Sumatra, Indonesia, (manmade, to clear forest for oil palm

plantation?)

• The haze formed when sulphides, nitrous oxides, and ash released by burning are

combined with the industrial pollution and exhaust from cities

• Pollution index = 500 (first time in Malaysia); 200,000 people were hospitalized

• Affected other countries in the region = $9.3 B economic losses

Documents

Nature Conservation Chapter 3.1