Seafriends: Summary of threats to
the environment By Dr J Floor Anthoni (2001 - )
by existing, people have made major impacts on the world's living ecosystems.
This summary attempts to list most of these, so that the enormity of the
situation can be observed. A century ago, this list would have been quite
short, because human use of the planet's resources was much less, and not
perceived as damaging. Today, not only can damage be seen or predicted,
it can also be felt personally in the form of shortages and hindrance.
Little do we realise, however, to what extent we have changed this planet.
In reading this compiled summary, please remember that it reflects just
a snapshot of today's situation, and that the world's population is still
to double in the coming forty years! Also remember that it lists the doom
side of developments, and not the positive actions (like conservation)
to alleviate these. So far, such remedies have, at best, been able to postpone
the inevitable for a few years. (recycling, fuel efficiency, green engineering,
crop genetics, etc.)
Not all changes to the planet's ecosystems are perceived as problems.
Only those that affect us are, particularly those that affect us
All our problems are caused by people, for without people there would be
no problems. Thus the more people and the more affluent their lifestyle,
the more resources they will use and the more numerous and severe our problems
will become. Ecological problems grow faster than the rate of population
and the growth of the world economy. For instance, a simple compounded
growth of 3% per year will double the world's problems in 25 years; growth
of 6% in 12 years! It is not surprising then, that the present generation
of school children will experience change as never witnessed before and
never to be witnessed again, as humanity exhausts some of its most precious
resources, while also causing serious trauma to the environment. The summary
below has been divided into four sections, for its effect on humans, the
atmosphere, the land, and the sea.
In this summary, we have omitted the benefits of humanity's growth and
development, such as major improvements to living standards, security,
health, education and the availability and quality of food, comfort, recreation
and sport, mobility and so on. These are amply experienced by those who
have the fortune to be economically secure. But the downsides of these
developments, are often not seen because they happen invisibly, unnoticeably,
slowly and somewhere else, and they are not advertised. The tremendous
progress made in conservation, is not mentioned here, like the cleaning
of rivers, progress in recycling, alternative farming methods and so on.
On the other hand, the summary presented here reflects only the tip of
the iceberg, being very incomplete.
threats to humans: health, food and water, shelter,
recreation, hindrance, social cohesion, wealth.
This article is particularly of benefit to people living in 'clean' developed
countries, not being aware that they depend on products that have been
farmed or manufactured in other countries, causing environmental problems
far away. Their needs ultimately result in environmental degradation that
they themselves do not experience, and are not aware of.
Seafriends is a small organisation championing the cause of our seas.
Our seas have become the sumps of civilisation, since all water runs down-hill,
taking with it all of society's soluble wastes. It is therefore also a
good indicator of the damage humans are causing to the natural environment.
Not surprisingly, the seas are becoming sicker, everywhere in the world.
You may not be directly interested in the sea, but in order to better understand
this summary of the world's threats, you may also wish to read from the
Seafriends web site:
soil: our most important
resource and most maligned, probably also most needed. How we are losing
sitemap: discover the gems of this
web site from our extensive and complete site map (11p)
Please note that this page is updated regularly and that it may never become
complete. The information has been derived from many sources, and is not
to be used for exact figures, but rather as an indication of the overall
picture. Please do not hesitate to inform the author of new environmental
problems or incorrect statements: e-mail Dr
-- seafriends home -- environmental
issues -- sitemap --
Revision: 20010518,20010630,20011016,20011119,20020723,20070725, threats to humans:
although the threats to humans cannot easily be expressed quantitively
or financially, their trends can be described qualitatively. We will get
more comfort, but at the cost of considerably more cost or hindrance. Economists
estimate that a 200% growth in population causes a growth in Gross National
Product of 300%, trickling down into a personal gain of no more than
30% (being 30% better off). However, discomfort and hindrance are likely
to grow more than 300%. It is an unwise trade-off that most people are
unaware of. Between 1950 and 1990, US per-capita GNP more than doubled,
whereas fewer people considered themselves 'very happy' (35% down to 32%).
In the past 150 years, world population grew five-fold and per capita consumption
four-fold, while a wide range of technologies was adopted, which were harmful
to the environment. The result is an escalation of human pressure on the
environment, of over twenty times since 1850.
weaker genome: by keeping people alive at all cost, while allowing
those with genetic defects to breed further, the human genome is weakened.
It appears that the underprivileged with low genetic qualities, breed more
prolific than those who have been more fortunate, inevitably lowering the
genetic quality of humans. Note that the mixing and intermarriage of races
counteracts this effect.
resistance to antibiotics: the widespread and unrestrained use of
antibiotics has created many strains of resistant disease organisms. Once
infected by these, death almost certainly follows by MDRs= Multiple Drug
Resistant bacteria. Incurable strains of tuberculosis, pneumonia, dysentery,
cholera, malaria emerged.
resistance to chlorine in drinking water: in 1993 400,000
people got sick in Milwaukee from a water-borne protozoon Cryptosporidium
which had become resistant to chlorine.
sick city syndrome: dense populations encourage the rapid spread
of diseases. City people are always a bit ill. Inside cocoons of comfort,
the air is recycled through air conditioners, and so are disease germs,
which are capable of travelling long distances through air ducts. Constant
environmental conditions inside shops, malls and offices promote strange
illnesses such as legionnaire's disease and many unidentified ones.
lack of sleep: late night TV, loud traffic, parties, keep people
up too late. It affects cheerfulness, induces illness and dulls learning.
It also reduces performance and weakens resistance to disease.
stress: people are hindering each other. More traffic lights. More
traffic. More traffic jams. More rules to live by. Quick communication
has hastened the pace of life. We do everything faster than 50 years ago,
but the human constitution has not evolved for such life.
noise pollution: Since 1960, noise has increased: cars + 162%, airline
+438%, trucks +483%. Helicopter overflights are increasing rapidly. Noise
at relatively low levels causes serious stress symptoms to some and hindrance
to many. Noise diminishes our sense of civility, numbs compassion, and
breeds aggression and hostility. Noise ranks higher than crime and traffic
as cause of dissatisfaction. About half of Americans live in areas with
noise above recommended levels. The EPA office of Noise Abatement and Control
was shut down by Ronald Reagan in the 1980s.
sperm count: over the past 50 years, world average
sperm count for human males has dropped by 40% and will continue to do
spread of contagious diseases: global warming, warm cities and urban
areas keep insects alive that would otherwise not be able to survive the
winter. Diseases and pest become established. Intensive travelling around
the world spreads pests and diseases. Increasing population densities make
outbreaks more frequent and their spreading more rapid. Malnutrition (both
fat, thin and wrongly nourished) makes people more susceptible to disease.
Chemical pollutants can affect immune response. High levels of nutrients
in the atmosphere rained down, make algae grow in pure rainwater, forming
breeding pools for mosquitos.
new diseases: hitherto unknown diseases are popping up everywhere.
More people are coming into close contact with infected wild animals when
clearing forests, living primitively, or eating bushmeat. Ebola, AIDS,
Marburg, Hanta, Machupo, West Nile viruses. Also new livestock diseases
such as BSE (mad cow disease). The disease agent of BSE, or CJD (Creutzfeld-Jacobs
Disease) is a prion, the most primitive of all life forms, which until
now, has not been harmful to humans.
poisons from mining, transport and industry:
Mining moves rock and soil to obtain its minerals, but once disturbed,
these can easily leach into the biosphere, often accumulating in plants
and animals. Poisons belched into the atmosphere by industrial processes,
cause respiratory diseases, birth defects (teratogenic) or cancer (carcinogenic),
and may affect immune and hormonal systems. They can also cause genetic
alterations (mutagenic). Recent findings have found most chemicals to be
more toxic than thought before. New chemicals are produced faster than
can be tested. Permissible standard for cancer: one death in 1 million
sulphuric acid: produced in the atmosphere from sulphur dioxide
emissions from burning coal and oil. It irritates lung tissue, causing
excessive amounts of mucus, which can suffocate a patient. London smog
of 1952 left 4000 dead at concentrations of 4.5ppm; that of Dec 1962 700
at 3 ppm.
low-altitude ozone: produced in the atmosphere from nitrous oxides
and sunlight. Ozone irritates the throat and lungs, with symptoms that
may be mistaken for hay fever, and likely to occur when ozone concentrations
exceed 80ppb (0.08ppm).
lead: is acutely toxic and causes subtle impairment of children's
brain development. It damages nervous system and inhibits mental development.
mercury, particularly methyl-mercury: the mad-hatter syndrome. Madness,
loss of balance, brain damage.
cadmium: the ouch-ouch syndrome of painful bones and joints.
asbestos: Asbestos was widely used for its resistance to heat. But
this finely fibred mineral can lodge itself in the fine tissues of the
lungs, causing lung cancer at a much later date.
formaldehyde from plastics:
chlorinated hydrocarbons (DDT):
food & water: humans are already consuming
some 40% of the terrestrial supply of all animals, and almost 50% of surface
water runoff (1995). Most water is used for agriculture. Then follows industry
and finally domestic use. Of domestic use, most is used for sewage, washing
and bathing. Of the 6 billion people on Earth, some 1.2 billion people
struggle to survive on $1 a day or less. 1.2 billion people lack access
to safe drinking water and 2.9 billion have inadequate access to sanitation.
About 150 million children are malnourished, and more than 10 million children
under 5 will die in 2001 alone.
poisonous rainwater: water collected from rain has become poisonous,
particularly in areas of high population densities and industry. Its nutrient
component of nitrites, nitrates, sulphur dioxide and sulphates has become
poisonous to humans.
poisonous aquifers and groundwater: particularly in highly productive
farming areas, where productivity is achieved by generous applications
of fertiliser and agrichemicals for pest control, ground water, aquifers
and rivers are becoming more and more polluted. It becomes more difficult
to find drinkable water.
salinated water: as aquifers become overexploited
and their levels drop, it allows seawater to penetrate and to take its
river salination: as river water is repeatedly used for irrigation,
it becomes saltier and polluted by agrichemicals, and totally unsuitable
for drinking, further downstream.
water cost: everywhere in the world, water is obtained with very
expensive means: long canals and pipes, pumping up-hill, distant dams,
desalination, etc. The cost of desalinised water is US$ 2-4; that of piped
water US$ 0.20 per m3. We've become dependent on fossil fuel, even for
our water. Desalinating 100Mm3 of water costs over US$ 100M. Already some
7,500 desalination plants are working worldwide. These prices are based
on the low cost of fuel in the 1990s.
safe water: more than a billion people do not have access to safe
water, and their numbers are increasing. Water is unsafe for drinking,
when mixed with surface run-off, human or animal excrement, or when it
is too muddy.
food cost: the fertility of croplands is diminishing rapidly, as
more and more fertiliser is used, resulting in dearer produce. Rich people
will command an ever larger share of the pie, while driving food prices
up, to the detriment of those who cannot afford to pay.
food quality: as more and more fertiliser is used, and food is produced
by hydroponics, it becomes less tasty. New varieties are produced for their
keeping ability and appearance; not for health and taste.
poisonous food: harmful and poisonous
plankton blooms are now so frequent that in 1998 Canada had 160 shellfish
closures each year along its British Columbia coast. Shellfish and fish
tainted with poisons can cause diurethic shellfish poisoning (DSP), neurotoxic
shellfish poisoning (NSP) and paralytic shellfish poisoning (PSP). In some
countries, humans die each year from these and a similar poison, ciguatera
in tropical areas. Harmful algal blooms (HAB) are increasing in both frequency
infected food: despite thorough sanitary regulations, food poisoning
is on the rise due to people eating out more frequently, and due to stocking
densities in feedlot farming. In several countries the dreaded BSE (bovine
spongiform encephalitis) has scared people away from eating meat. Other
food-transmissible diseases are on the rise too.
world food demand: will increase by a factor of 3 in the next 50
years, but agricultural production has reached a maximum.
paving the best soils: settlements developed where living was good,
usually where good soils were found. As cities sprawled, all the best fertile
lands were paved over, being lost forever, and threatening our source of
food. It also affects underlying groundwater and aquifers.
climate/ atmosphere: more severe weather,
more storms, heavier rainfall, more cloud. Air pollution was known in industrial
places with dense populations and metal smelters, already 2000 years ago,
but it has spread and intensified. Since 1940 various clean air regulations
reduced it by at least half, but subsequent use of the motor car has undone
all progress. Now it rules in all cities, causing discomfort, disease and
air pollution: In the 20th century, air pollution killed 25-40 million
people, roughly equal to the combined kill of World Wars 1 and 2. In the
USA 30-60,000 people are killed this way, each year, the same as in Poland
or Czechoslovakia, but it mainly affects elderly people.
ultraviolet radiation: due to industrial gases like CFCs, the protective
ozone layer has thinned and will remain so to past 2050. It causes more
monster rains: rainfall has become heavier almost everywhere in
the world. In some cases, a single rain may drop up to two years of rainfall
in a single day. Such monster rains destroy lowland infrastructure while
killing tens of thousands of people (Bangladesh 1991, Hurricane Andrew
1992, Mississippi 1993, Cyclone Mitch 1998, India Gujarat 1998, Venezuela
1999, India Orissa 1999), and they are becoming more common (4 times more
common than 50 years ago, and economic losses 15 times). As megametropolises
swell with large numbers of people (shantytowns), they also put themselves
in harm's way, resulting in increasing numbers of casualties. The huge
economic losses affect wealth, earnings and debt.
storms: storm intensity is increasing, as storms become more erratic,
accompanied by higher losses.
droughts: people are killed by famine from droughts and by forest
fires. These are increasing alarmingly.
cost of real-estate: as space becomes more heavily competed for,
its price goes up. The cost of dwellings will be dominated by the cost
of the land they are built on.
expanding cities: urban sprawl makes carbon emission the fastest
growing issue. As cities grow, people need to travel longer distances to
meet, recreate and work. It also pollutes the air faster than growth, causing
respiratory and other illness. Between 1950 and 1990 Chicago's population
grew by 38% but its area increased by 124%. While cities sprawl, public
transport also becomes less efficient. 300,000 hectares of forest are lost
in the United States every year, all of it due to 200 cities spreading
out over the land.
shantytowns: as more and more people become
displaced from the countryside, due to failing agriculture and agricultural
automation, they come to the cities to find jobs and a means to survive.
These people have usually lost everything they possess, and are able to
subsist only in densely populated shantytowns. Living in cardboard boxes
and deprived of sanitation, life is very unfair to them. The number of
people in this condition is rising frightfully.
decaying neighbourhoods: people who are feeling disenfranchised
and marginalised by more successful people, may lose interest in life and
the maintenance of their dwellings and neighbourhoods. Slums develop and
antisocial behaviour. As the difference between poor and rich grows larger,
more people become disenfranchised and more slums develop, and with it
acid rain damage to monuments: Most old buildings were built with
limestone, cemented together with limestone cement. Acid rains of sulphuric
and nitric acid dissolve both stone and mortar, resulting in irreparable
damage. Statues made of marble, a form of limestone, are also susceptible
to acid rain. The Acropolis in Athens was damaged more in 25 years than
in all 2400 years before. It cost Europe $9 billion per year to replace
corroded stone. Other pieces of art like frescos (paintings on wet plaster)
are beginning to break up. Arms fall off statues. Marble in London needs
to be polished every 4 weeks, due to the etching effect of acid rain. Most
of the stone of London's West abbey has been replaced by modern Portland
stone at a cost of nearly $15 million. Erosion proceeds at 0.08-0.2mm/yr.
Limestone dissolves 70 times faster in typical rain (pH=4) than in
unpolluted rain (pH=5.25). Buildings appear to receive most damage from
a few heavy rainstorms. Acid rain also ruins stained glass windows. Since
the 1950s, deterioration of medieval glass has accelerated that total loss
is feared before the new millennium. Modern glass is less at risk. The
carillon of the Dom church in Utrecht (Holland), made of bronze bells,
has corroded in 30 years to the effecct that it is now permanently out
acid drinking water damaging pipes and valves: even drinking water
is now acid enough to dissolve the steel pipes and valves through which
it is transported. Corrosion blisters inside pipes reduce their flow dramatically.
The cost of upgrading the drinking water infrastructure is crippling.
libraries: books in city libraries decay twice as fast as those
held in country libraries. Acid gases make paper acid, turning the paper
brown and brittle, while destroying the paper's cellulose molecules. Leather
shows a 'red rot' disease, caused by acid air.
ozone: low-altitude ozone oxidises almost every kind of material
from paper to fabrics and from metal to paint, causing mayhem to museum
clean water disappearing: clean rivers, springs and coasts have
become a thing of the past. Most people today can't even remember them.
beaches disappearing: beaches all over the world are disappearing
because of erosion and pollution.
beach closures: everywhere, the beaches are closed for extended
periods in summer, each year. In 2000, the USA suffered over 11,000 beach
closures (twice that of 1999), mainly due to stormwater runoff, sewage
pipes breaking, sewage discharge, etc. In 2002 over 12,000 beaches were
closed due to fecal contamination (USA).
hindrance: as more and more people vie for
a smaller piece of the cake, they will hinder one another more and more,
resulting in daily friction, increase in stress levels, etc. In 1950 only
3 cities exceeded 10 million inhabitants; by 1997, their number had risen
less parking space: parking becomes dearer and more difficult to
more traffic jams: travelling becomes slower; more of one's time
is spent travelling.
less free time: despite the benefits of fossil fuel, computers and
robots, and although the economy will keep providing jobs, more and more
of these will be spent on solving new problems. Instead of having more
spare time, people will have to work harder.
social cohesion: Water is more important than
any other resource on Earth, and more so as it becomes scarce. Unlike any
other resource, it is both important and in places scarce, while very unevenly
distributed and often being shared between nations. These are compelling
reasons for international conflict. Water shortages also lead to food shortage,
poverty and the spread of diseases.
globalisation: the spread and concentration of globally operating
corporations is threatening the social and cultural diversity. Often referred
to as 'cocacolonisation' it flattens the diversity in food, cities, homes,
transport, music, movies, etc.
social inequality: the rich are becoming richer and the poor poorer.
The poor have to suffer the consequences which the rich can afford to avoid.
unemployment: At least 150 million people
are unemployed and 900 million are 'underemployed'-contending with inadequate
incomes despite long hours of backbreaking work.
generation gap: Some 34 percent of the developing world's population
is under 15 years of age. The young differ more in their values from their
parents than ever before.
dishonesty: dishonesty will be increasing. For many, dishonesty
will become a way of earning a living.
litigation: as people hinder one another more and more, and the
environment is stiffly regulated, litigation will increase, creating wealth
for the legal professions, at the expense of others.
water wars: where water has become scarce, and
rivers are shared by several countries, tensions have risen as the demand
outpaces supply. One can live without a home but not without water. "Whiskey
is for drinking, but water is for fighting over", said Mark Twain.
Wars in many places of the world are looming. (Israel, Turkey, Syria, Iraq,
Egypt, Sudan, Ethiopia, Thailand, Vietnam, Mauritania, Senegal, Brasil,
Argentina ). Two or more countries share some 261 of the world's rivers.
These international water catchments account for about 60 percent of the
world's freshwater supply and are home to about 40 percent of the world's
people. An analysis of 1,831 international water-related disputes over
the last 50 years reveals that two thirds of these encounters were of a
cooperative nature while one fourth were hostile. On 37 recorded
occasions, rival countries went beyond verbal antagonism and fired shots,
blew up a dam, or undertook some other form of military action. This will
increase with time.
poverty wars: as soils degrade and populations famine, despotic
rulers rise and civil wars are fought. (Congo, Nigeria, Afghanistan). large
numbers of people are migrating for lack of food or drinking water, and
for security of life. In China, over 25 million people migrate due to drought,
urban wars: wars will be fought with small arms inside cities and
amongst innocent bystanders.
proliferation of weapons: weapons of mass destruction will become
available to many, shifting the balance of security, and affecting particularly
the secure free world. Small arms, mines and grenades will proliferate
terrorism: terrorism will increase, both
in numbers of attack and severity, as the gap between poor and rich widens,
and as trade favours the rich countries at the expense of the poor ones.
ecological collapse: several global ecosystems are teetering on
the balance of collapse, including the coastal seas, rivers, forests, croplands
and marginal lands. It leads to people shifting, becoming refugees within
their countries, and eventually trying to escape their countries.
drug abuse: the demand for drugs has been increasing steadily and
unstoppably, feeding the need for immediate pleasure of people in rich
countries. Poor countries, assisted by criminals will find new ways to
expand this trade and to invent novel substances. It may lead to drug wars
between western governments and drug lords.
political power shifts: countries with economic strength now hold
the balance of power, but this may change. The USA becoming entirely dependent
on imports of energy, will succumb to increasing balance of trade deficits.
Its agricultural production will reduce, no longer allowing it to trade
food for favours. Eventually it may need to import grain for its burgeoning
cattle and pig feedlots. Oil producing countries will become wealthy instead.
refugees and illegal immigrants: people flee
their countries in ever large numbers, because of oppression or for environmental
reasons like food shortage or for economic systems collapsing. In 1995
the world counted 25 million environmental refugees. Their numbers will
increase dramatically as the environment degrades further, while populations
keep increasing. Many will leave their countries as boat people
in the hope of being accepted into some other country. Illegal trade in
migrants becomes rife. High profits are made by immigration 'consultants'.
wealth: cleaning the environment becomes increasingly
costly, as is space, water and food. The environment may become the highest
cause of litigation, making life unpleasant and expensive.
higher cost of living: more is spent on environment, less remains
available for wealth or comfort. The environment is rapidly becoming the
biggest of all businesses. Spending on mitigating environmental threats
more spending on war: as the West's security diminishes by burgeoning
numbers of disenfranchised people elsewhere, the cost of defending freedom
will escalate. In 2000 some 780 billion was spent on the military, worldwide.
running out of financial resources: as the environment supports
less and less people (becoming dearer while not producing more), society
can no longer afford its current overhead of administrators, scientists,
teachers, police, army and so on. A shortage develops in essential professions
such as teachers and nurses.
insurance becomes insolvent: the amount of capital owned by insurance
companies becomes inadequate to cover the enormity of the problems. Terrorist
attacks, hurricanes, flooding, earthquakes, oil spills.
threats to the atmosphere and water cycle
The atmosphere weighs only 0.03% that of the ocean, and is therefore easily
polluted. The atmosphere is well mixed, both horizontally and vertically,
resulting in problems being spread all over the world.
climate change: warmer climate, more extremes; floods and droughts.
atmospheric change: exhaust gases from transport and industry, methane
from livestock, nitrous oxides and methane from soils, and trace gases
play an important role.
Carbondioxide CO2: was only 0.029% (290 ppm), rendering the planet
33º C warmer than without it. It has increased to 0.035% (350 ppm)
due to human use of fossil fuels. The use of fossil fuel currently accounts
for 80 to 85% of the carbon dioxide being added to the atmosphere.
Methane CH4: produced by fossil fuels, livestock, rice fields, soil,
mining. Used to be 0.9 ppm, but has increased to 1.7 ppm. It is a potent
Chlorofluorocarbons: from refrigerants, foams, aerosols. It destroys
ozone molecules in the troposphere and adds to the greenhouse effect. It
used to be zero, but is now 0.003 ppm.
Nitrous oxide N2O: from deforestation, fertilising, burning biomass.
Was 0.285 ppm; is now 0.31 ppm.
Nitrogen oxides NxO: fossil fuel burning. Causes acid rain and smog.
Its concentration is high close to industries and cities.
Sulphurdioxide SO2: from fossil fuel burning and ore smelting. Produces
acid rain and smog. Is more concentrated near cities. It washes out easily
from the troposphere (4 days residence time) but concentrates in a narrow
band above it at around 20km height.
Ozone O3: from vehicle exhaust reacting with sunshine. Acts as a
greenhouse gas, causing smog. Was 0.01 ppm ad has increased threefold.
This ozone is not caused by solar radiation as that found above the troposphere
smog and vapour: Major improvements have been
made in smog abatement in all cities after the introduction of electricity,
natural gas and clean air regulation, but car exhausts have taken over
where industries left off. A year-round smog over the Indian Ocean and
Asia is blotting out 10 to 15 per cent of the sun's rays, with potentially
very major consequences for the atmosphere. (1995 Nobel prize-winner for
chemistry, Paul Crutzen). Smog is formed by a confluence of geography,
climate, wealth and culture.
London: In London, coal was burnt for industry, cooking and home
heating. Steam vehicles added more. After electrification, most smog disappeared.
But sunlight could now interact with vehicle exhaust gases, creating a
new health problem. London's effective Underground transit system keeps
emissions down. In 1952 a severe smog killed 4000 people. The last serious
smog dates from 1968. Now open fires are prohibited and stoking is done
on natural gas.
Europe: smog is a main problem in East Block countries and cities
like Katowice and Warsaw in Poland. 30% of the trees in what was once Czechoslovakia,
have been damaged by acid. Trees in the Erzgebirge have disappeared and
soils are eroding badly. The smogs from industrial areas in Germany have
abated, but car exhausts on Autobahns are causing a new threat.
Los Angeles: was built for the automobile. It even abolished public
transport. Located in an area with mild winds and surrounded by mountains,
often a thermal inversion layer forms. Smog from the day before may blow
back over the city.
Athens: with an industrial history like that of London, Athens does
not have good public transport. The siesta tradition creates four traffic
peaks a day with long traffic jams. By 1990 Athen's smog was six times
that of LA.
Others: Mexico City, Calcutta, Beijing, Cairo, Shanghai, Seoul,
Dhaka, Lagos, Djakarta, Bombay, Buenos Aires, Caracas, Karachi and so on.
vapour trails: the clear blue skies of the
desert city Las Vegas (USA), every day by 10:00 in the morning, become
overcast by the vapour trails of jet liners visiting the city and passing
over. Vapour trails diminish incoming solar radation over the most populated
acid rain: 85% of the lakes in the Adirondack Mountains have been
acidified by industry. Acid deposition of sulphates and nitrates has made
thousands of lakes in Scandinavia and North America virtually lifeless.
Salmon have disappeared from the southernmost rivers in Norway. Acid rain
has caused forests to die (waldsterben): it affects leaves directly
through its sulphuric acid content, and accumulates in the soil, preventing
roots from functioning. The amount of sulphur produced per person (1985):
Germany 240kg, Czechoslovakia 201kg. It translates to 35ton per km2 or
350kg/ha, about ten times the fertiliser requirement of agriculture. In
the Ukraine, sulphur fallout exceeds 120kg/ha.
black snow: oily soot in rainwater shows itself as relatively harmless
black snow, but it covers leaves in a tarry soot, preventing them
from functioning. Tall chimneys on power plants now belch their pollutants
high into the atmosphere, causing problems far afield where they did not
exist before. Buildings and monuments become covered, requiring additional
maintenance. Lichens (liverworts) disappear.
destruction of the ozone layer: causes an increase
in UVB radiation, causing radiation damage to living tissues of plants
and animals, while affecting plankton ecosystems near the surface of the
oceans. UVB penetrates up to 5m into the oceans.
water cycle: conversion from forest to agriculture and urban areas,
increases the soil temperature while decreasing soil moisture, causing
extreme temperatures, floods and droughts. Rainwater runs off too fast,
being lost for pants, while also causing flooding downstream. All major
continents are seriously affected. A reduction in the water cycle also
promotes more and larger bush fires. Fires in Canada's northern forests,
mostly triggered by lightning, are responsible for some 20% of this country's
carbon dioxide emissions.
Argentine: temperature increase of several degrees C; droughts and
China: droughts, desertification, loss of over 2000 km2 of cropland
loss of agricultural output: Climate change will reduce output in
the tropics and subtropics. Forty of the world's poorest countries (2 billion
people) face losses of more than a quarter of their food production as
a result of global warming. They include India, Brazil, Bangladesh, Ethiopia,
Sudan and other nations with a recent history of famine. Other prominent
losers will include Thailand, Nigeria, South Africa and Colombia. 12% of
all land is now under permanent cultivation.
planting forests: Forests will not be planted in productive but
in marginal areas. It could increase global temperature because forests
absorb more light/heat (than snow/bare land), and could cause more forest
burns (in drying areas). A hectare of immature forest can absorb about
75t of carbon each year, despite growing slowly.
land, terrestrial threats
80% of known species are terrestrial, but only in 20% of the known phyla.
communism: "The environmental desolation created by the Communist
regimes is a warning for the whole of civilsation" (Vaclav Havel, president
of the Czech Republic). In communist countries, bad news about the environment
has been censored. Production quotas overrode all other considerations.
drug use and abuse: the demand for pleasure drugs like cocaine and
marijuana encourages farmers in poor countries to clear forests and to
overexploit their soils.
Traditional Eastern Medicine: ancient beliefs in healing powers
of rare and weird animals, causes these to disappear from the wild. As
their price goes up, it becomes nearly inpossible to protect them from
subsidising unsustainable industries: strapped for overseas exchange,
many governments subsidise industries beyond their levels of sustainability.
distant fishing fleets: fish can be found in low densities but over
large areas in the open oceans where primary productivity is low. They
can be fished with large vessels at the expense of large amounts of fuel.
Not sustainable by themselves, they can work with subsidies. It has led
to overfishing and overcapacity of fishing fleets.
logging native forests: native forests take a very long time to
recover. They contain hardwoods which are in demand overseas, earning valuable
foreign exchange. Governments encourage their exploitation, even when knowing
that recovery may take hundreds of years.
subsidising the cost of water, by public projects: India, California,
Arabia, Israel, Tunisia, Nigeria.
US subsidies to agricultural irrigators amounts to $1250/ha /year.
water: demand for water is increasing twice
as fast as population grows. Water is the most critical issue facing human
development. To live decently, each human needs at least 50 litres each
day (drinking=5, sanitation=20, bathing=15, cooking=10, total= 18 m3 per
year). Agriculture and industry use some 500-1700m3 per year per person.
Less than 200m3 is considered 'critical' to life. Since 1950, the global
renewable freshwater supply per person has fallen 58% as world population
has swelled from 2.5 billion to 6 billion. By 2015, nearly 3 billion people
(40 percent of the projected world population) are expected to live in
countries that find it difficult or impossible to mobilise enough water
to satisfy the food, industrial, and domestic needs of their citizens.
rivers: the water of rivers is used repeatedly for irrigation. Some
of it evaporates, and the returned water becomes more saline while also
more contaminated. Towards the end of their course, rivers often become
intolerably salty and polluted. The flow of rivers has become entirely
unnatural, controlled by human need for either electricity or irrigation,
and marginalising the environment in the process. Freshwater life has become
irrigation & ground water: Per capita irrigated land is shrinking
(nearly 1% annually). About 230Mha is now under irrigation (0.045 ha/ person).
Salinated soil is spreading at over 1Mha/year. As more and more artificial
lakes are made, less and less rain falls on the land. Industry's use of
water produces 50 times more value than that of agriculture, and industry
is growing much faster than agriculture. Tourism even more. Food production
declines. 1 kg of wheat requires 1000kg of water. 1 kg of beef requires
50,000 kg water! Half of the world's supply of fresh water is now appropriated
by humans. More than half the world's diverted water is wasted through
evaporation and infiltration. In 1980 salinisation corroded agriculture
on about 25% of its irrigated lands. By 1990, salinisation affected over
10% of all irrigated land. By 1996, more irrigated land was ruined than
could be created. Reservoirs and canals spread diseases like malaria, schistosomasis,
cholera, typhoid and more. Water tables are falling from the overpumping
of groundwater in large portions of China, India, Iran, Mexico, the Middle
East, North Africa, Saudi Arabia, and the United States. Many major
rivers—including the Colorado, Ganges, Indus, Rio Grande, and Yellow—now
run dry for portions of the year.
The Ogallala aquifer runs beneath 580,000km2 of the Great Plains,
feeding 7Mha of irrigated land (America's bread basket) through 74,000
wells, is drawn down by 17km3/year, dropping its water table by almost
1m/year in 1995, and threatening half a million farmers. In places its
water table dropped from -230 to -450m! Already over 60% of its volume
The Rio Grande has become one of the most polluted waterways, containing
untreated sewage, pesticides and industrial wastes. Water-related problems
have been identified as the primary health concern of people on both sides
of the border with Mexico. As it enters Mexico, its salinity has risen
to 1500 ppm (the sea is 35000 ppm), totally unsuitable for any use at all.
The southern states California, Colorado, Arizona, Utah, Wyoming,
New Mexico and Nevada are running out of water, despite careful use of
it. Very little water is left for the environment.
Owens Lake in California, dried up and polluted with salt and biocides,
is blowing its saline dust around, polluting the air people breathe. The
waters of the Owens Valley had been drained nearly a century earlier, to
water Los Angeles and surrounding farmland.
The Central Valley of California has subsided 10m in 50 years.
Mexico City has dropped unevenly 7-15m in some places because of
overpumping its aquifers, damaging its sewers and infrastructure.
Middle-East: The level of the Dead Sea has plummeted more than 10m
over the last 100 years. The river Jordan has been reduced to little more
than a drainage ditch. The Sea of Galilee (Lake Kinneret) is shrinking
and threatening to turn saline, being almost undrinkable already. In Gaza
overpumping of aquifers is drawing seawater in, rendering them unsuitable.
Israel overexploits its aquifers by 15% a year. One quarter of its water
comes from the politically disputed West Bank. Most countries near the
Arabian Peninsula are fully using all available ground and surface water.
Other countries will reach that point in a decade.
Russia: the water level in the once pristine Lake Baikal, the deepest
fresh water lake in the world, is sinking steadily while also its quality
deteriorates. The Aral Sea has become the world's greatest man-caused catastrophe
by diverting its waters for irrigation since 1956. By 1960, the lake began
to shrink by some 50 km3 per year. By 1982, commercial fishing had stopped.
With over 28,000 km2 of dried bottom, it became a lifeless stew of salt,
pesticide residues and toxic chemicals.
England: since 1990 the water tables began dropping.
Africa: the Sahara desert is expanding. Lake Chad is shrinking at
nearly 100m a year. Water supplies in the Nile are in peril. The Nubian
Aquifer in the Kufra basin has 40 billion m3 water.
The Nile, largest river in the world, runs through 7 countries and
its waters are already fully utilised. The Aswan Dam creating Lake Nasser,
has caused major ecological damage downstream, all the way to the Mediterranean
Sea. The Nile valley soils are salinising, the Nile Delta is eroding. The
amount of nutrients discharged in the Mediterranean Sea has been reduced
considerably, resulting in the collapse of the sardine and shrimp fisheries.
Through lack of fresh water, the sea is becoming saltier too, resulting
in major ecological change. Improved agriculture with artificial fertilisers
has allowed the Egyptian population to double in less than 30 years. Major
outbreaks of diseases accompany the disaster.
Libya's Great Man-Made River transports water from the Nubian sandstone
aquifer. A network of thousands of kilometres of pipes pumps water from
hundreds of wells, transporting 350 + 700 + 560 + 350 = 2000 Mm3/yr, costing
US$34 billion, while delivering water at the cost of 0.25-0.30 US$ per
m3. It is rapidly depleting huge, ancient aquifers.
Asia: Today Asia has approximately 60% of the world's people but
only 36% of the world's renewable freshwater.
India: in Bangladesh the water table is dropping by more than 1m
China: in millions of ha of northern China, the water table is dropping
by 1m a year. Whereas the USA depends for 17% on irrigated agriculture,
China depends for 70% on it. China's population grew from 0.5 to 1.2 billion
in 1950. China is running out of water where it is needed most: 3/4 of
the water is in the south, whereas 3/4 of the farming is in the north.
80% of the rivers contain water unfit for human consumption. Rains fall
unpredictably from year to year.
Almost half the number of cities (300) have run short of water; some 100
In 1996 the largest river, the Yellow River, was dry for one third of the
year. In 1997 it failed to reach the sea for 2/3 of the year.
Industry is able to pay more for scarce water than agriculture.
drinking water: More than 3 million people—most of them children—die
each year from diarrhea and other illnesses caused by contaminated water.
Between 1990 and 2000, an additional 816 million people acquired access
to safe drinking water.
Saudi Arabia desalinates 2.5 million m3 a day! Its aquifers are
being overpumped by 5 billion m3 a year, running out in 50 years!
dams: By 1980 there were over 36,000 large dams
in the world. Dams prevent flooding, buffer rains, provide drinking water
and allow irrigated intensive agriculture to flourish. But dams affect
the ecology of rivers and the hydrology of the land. As the dam lakes are
filled with silt, they hold less and less water, while depriving downstream
floodlands from fertile mud deposits. Dams in dry countries produce lakes
which evaporate with as much as 2m each year, causing substantial water
losses (5-20% of a river's water, depending on the number of dams). Since
1950, the number of large dams (those at least 15 meters high) has climbed
5,000 to 45,000—an average of two new large dams a day for the last half
Egypt: the Aswan High Dam has become an unmitigated disaster. Silt
from the Nile river can't pass through, resulting in collapse of down-stream
fisheries, erosion of its delta's shore line, and salinisation and degradation
of soils. Its irrigation channels have led to an epidemic of the bilharzia
India: between 1955 and 1985, 13 million ha (the size of Greece)
had to be withdrawn from cultivation due to salinisation.
industrial water: industry is able to pay more for water because
it produces more valuable goods than farming. Likewise, tourism is able
to pay more, for filling their swimming pools and watering their golf courses.
Water is taken from agriculture and sold to industry. Farms dry up. Food
becomes scarce and needs to be imported.
forestry: During the 1990s, the loss of natural forests was 16.1
million hectares per year, of which 15.2 million occurred in the tropics.
The countries with the highest net loss of forest area between 1990 and
2000 were Argentina, Brazil, the Democratic Republic of Congo, Indonesia,
Myanmar, Mexico, Nigeria, the Sudan, Zambia and Zimbabwe. Outside tropical
countries, 0.9 million hectares of natural forest were lost per year. Exotic
forest plantations increasing at 3.6 million hectares annually. Cutting
the forests changes the water cycle, resulting in droughts, which cause
forest fires, and so on.
unsustainable hunting: About 15 primate species are believed to
be threatened by the commercial bushmeat trade. The number of chimpanzees
in Africa is believed to have declined by 85 percent during the 20th century.
Other species threatened by the bushmeat trade include the forest elephant,
the water chevrotain (a small hornless deer), six duiker species (ducklike),
the leopard and the golden cat.
farming: fertilisers, erosion,
intensive farming: hog, poultry and dairy cause nutrient runoff,
resulting in river, lake and coastal plankton blooms.
agrichemicals: the use of agricultural biocides has resulted in
the loss of insects and other organisms, while severely disrupting the
illegal crops: cocaine, marijuana. Forests are cleared and the soil
is farmed exploitatively for large profits. Soil loss and erosion. South
Americas: Andes mounains, Colombia (Cocaine). Papua New Guinea (marijuana).
aquaculture: freshwater aquaculture in
fish ponds has proved successful, while providing food to many, but mariculture
at the margins of the sea has had mixed successes. The shrimp cultivation
has resulted in large scale destruction of coastal mangrove forests. After
a few years of operation, the environment became poisoned by the amounts
of artificial food used, and the fishery was abandoned.
Chinook salmon: declined by 99% since 1969. Others; steelhead: over 50%
of all salmon species under severe threat.
aquarium trade: colourful species are being
harvested from tropical rivers, threatening their existence. Amazon river.
competition for food:
soil erosion and loss: due to deforestation and
subsequent use for cropping and ranging, particularly in areas with either
very low or very high rainfall, soil is lost to deterioration or erosion.
Total amount of arable land is about 3% of the Earth's surface. People
induce 60-80% of all soil erosion. Eroded soil often takes centuries to
find its way to the sea. Soil compaction increases as farm machinery becomes
heavier. 2 billion ha now degraded, about a quarter of all cultivated land.
UNFAO estimates that erosion alone destroys 0.3-0.5% of the world's cropland
every year. (Population grows at 2.2%). Overgrazing is the most pervasive
cause of soil degradation, affecting 679 million hectares (35 percent of
all degraded land)
China: in 2001 the largest dust storms ever, reached the USA. It
signals a rapid deterioration in the quality of China's rangelands and
croplands. In 1994 a law required the government to develop as much new
land as was taken by industry. Numbers of cattle and sheep have increased
to sustainable levels. Each year 2330 km2 is turning into desert. In 1978
erosion had forced the abandonment of 31% of all arable land.
Australia: overgrazing caused up to 80% of land degradation.
drought and desertification: More than 100
countries in all climatic regions on all continents are seriously affected
by desertification, the United Nations Food and Agriculture Organization
USA: Several parts of the nation, from the Pacific Northwest to
the Southeast, are suffering from severe, ongoing droughts.
forest: Since 1700, nearly 20 percent of the world's forests and
woodlands have disappeared. Large areas of forest are burned during war,
in order to flush out guerilla fighters. Chemical defoliants like Agent
Orange caused permanent damage to forests in Vietnam. Forests were cleared
to build wooden war ships and merchant ships.
Florida lost over 3.5 million ha.
By 1970, the USA had lost roughly 50% of its original coastal wetlands.
Thailand has lost more than 50% of its mangroves (shrimp mariculture).
Maryland lost over 50% of dune habitat.
USA barrier islands: 95% of natural dune habitat lost.
disturbance: through mining and soil erosion,
humans moved 42 billion ton of earth, compared to volcanoes above and under
water 44 billion. By 1980, mining moved more rock than natural erosion
damming rivers: most rivers in the world have been dammed several
times, disrupting their normal flow and wildlife.
development: development for housing is particularly destructive
along the coast, where dunes and wetlands have all but disappeared.
disappearing wetlands: wetlands are easy targets for land reclamation.
Most wetland habitat has disappeared worldwide.
roading: roading causes a permanent disruption due to the policy
of gradual improvement. Road sides are continually scraped to widen roads,
to clear up slips, and so on. In the process, they contribute enormously
to the amount of silt reaching rivers and the sea.
mining: mining creates a profound disturbance to the soil and subsoil.
It causes mud to run off into rivers. Minerals, once safely locked underground,
now become exposed and poison the environment.
species diversity: Extinctions happen
about 10,000 times faster than natural replacement by evolution. Natural
species represent a living library of options for adapting to local and
global environmental changes, on which future generations depend. Humans
have already destroyed one quarter of all bird species in the past 2000
years. Extinction now proceeds at the rate of 1,000 and expected to rise
to10,000 species per year, or 3-30 per day! Most will be in insects because
they comprise 98% of all species. Normal extinction rate is 1 out of 5000
mammals every 200 years, but since 1600, at least 484 animals and 654 plants
have gone extinct, most on islands and in lakes. Mammals die out 40x faster,
birds 1000x than normal. 1% of all birds and mammals went extinct in the
20th century. Many experts think that 30-50% of all species will go extinct
in the 21st century, based on calculations of habitat loss.
(See McNeill 'Something new under the sun')
loss of endemic species: endemic species are severly threatened
by habitat loss, predation by introduced predators, and extraction. (See
zebra mussel: Great Lakes USA/Canada, catching a ride in ballast
water from the Black Sea. These mussels have successfully smothered all
habitats, causing severe hindrance to water inlets and power stations,
while disrupting the natural balance.
USA: in 500 years, more than 30,000 foreign species have been introduced,
ranging from valuable crops to harmful pathogens. The impact of invading
species has been estimated at US$ 138 billion/yr. The Kudzu vine is spreading
rampantly in southren US. Fire ants have invaded agricultural land, resulting
in loss of productivity and native species.
Africa: the introduced Nile Perch into Lake Victoria has extinguished
almost all native fish species there (over 200), resulting also in loss
Islands in the Indian and Pacific Oceans: have lost as many as one
quarter of the world's bird species through predation by rats, stoats,
pigs and dogs.
inbreeding: the loss of sufficient habitat is causing populations
to lose genetic diversity. All large carnivores (tiger, lion, etc) and
large herbivores (rhinos, etc) now suffer from a substantial degree of
inbreeding, eventually leading to complete extinction.
chemical pollution: chemical wastes from
industry have been dumped in hundreds of thousands of sites, often illegally.
The cleanup effort is going much more slowly than anticipated. Chemicals
disposed of in sewage systems, poisons sewage and sludge treatment.
energy: the burning of fossil fuels causes major pollution to the
atmosphere, causing acidified lakes and dying forests (waldsterben). Nuclear
energy generation has other problems. Acidified lakes surprisingly, look
crystal clear and healthy, supporting green carpets of algae but the cycle
of decomposition, which provides nutrients for other species, has slowed
down. Fish can no longer live there, poisoned by aluminium compounds generated
from the soils by acids. Many lakes have lost their ability to neutralise
transport: rubber, mineral oil and heavy metals are spread all around,
washing from the road into rivers and then to the sea.
mining: By 1980 about 10% of Japanese rice paddies had become unsuitable
for human production due to Cadmium poisoning of the soil. Polish Silesia
showed unhealthy concentrations of cadmium, mercury, lead and zinc. Canada
Ontario: nickel and copper mining killed almost all vegetation down-wind.
Lead persists for 300 years in soil.
industry: PCB, CFC, PAH,
dumping/ incineration of hazardous wastes: USA chemical companies
and the military dumped 80-85% of their wastes into nearby pits, ponds
and rivers, resulting in cancers and other diseases (Love Canal). 50,000
toxic waste dumps in America.
toxic trade: poor countries are paid to take the toxic wastes of
rich countries, much of the trade is illegal.
harmful algal blooms (HABs): toxic or harmful blooms are increasing
in frequence and severity. Many bloom species produce virulent toxins that
accumulate or kill outright. Pfiesteria piscicida kills fish. (N Carolina,
Maryland, Virginia); causes memory loss.
light pollution: in many places the night has
become so light (due to the light from cities and roads) that it upsets
the nocturnal animals. Daytime predators are now able to hunt by night.
road kill: the road has become a major sink for wildlife.
introduced species: see above.
disease: diseases are spread by the transport of livestock across
habitat fragmentation: roads cut through habitats, carving them
up into smaller fragments, with insufficient interaction between them.
Roads introduce boundary effects, thereby reducing the effective sizes
of the fragmented habitats.
long-term unspecific decline: the cause of
decline is unknown. New diseases are emerging, caused by pathogens that
may have been harmless in their original setting, but turned nasty when
released among previously unexposed hosts. All over the planet, lethal
infections are killing off populations of creatures ranging from abalone
to kangaroos, from coral to honeybees, and from pilchards to flamingoes.
humans: see effects on humans above.
mammals: Rinderpest, a virus brought to Kenya with imported cattle
in 1887, killed three-quarters of the native antelope, kudu, wildebeest
and other ungulates in southern Africa within ten years. When distemper
virus was brought to the North Sea in 1988 by hungry harp seals-driven
from the Atlantic by overfishing-it killed three-quarters of the local
birds: Griffon Vultures (USA). After West Nile virus arrived in
New York from Israel last September, the virus also killed ten thousand
crows in New York City alone. Migrating birds might now have spread the
virus across North America (New Scientist, 8 July, p 4).
reptiles and amphibians: a fungal disease is killing off amphibians
worldwide. The world’s amphibian population is undergoing a die-off of
unprecedented proportions, most ikely as a result of a combination of human-caused
environmental problems. According to researchers at the World Conservation
Union, almost a third of the 5,743 known species of frogs, toads, newts
and salamanders on Earth are facing extinction within the next few years.
diseases: are spreading and increasing in number. Sudden mass mortalities.
rising sea livels, drowning land: Scientists predict a sea level
rise of 1m by the end of the 21st century (1995 estimat), and their estimates
have gone up to 4m (2001 estimate). It would drown much productive land,
some cities and some enitre countries.
Maldives: would disappear entirely.
sea, marine threats.
20% of the known species are marine, but they comprise 80% of the phyla.
Many marine species (bacteria, viruses, etc.) have been poorly studied.
Several lifestyles are totally absent on land, such as filterfeeding. Marine
foodwebs are more complex than terrestrial ones. There is less spatial
complexity (trees/coral), less variation (temperature, etc) thus more sensitivity
to environmental changes.
The basic nature of water, that of dissolving many chemicals, makes
water pollution a threat to marine organisms. Since nutrients in the ocean
are naturally hard to come by, many marine organisms are capable of concentrating
these, including human-made chemicals. The chemistry of pollution reacts
with the chemistry of life.
Traditional Eastern Medicine: sea horses, pipefishes and sharks
are threatened because of their supposed medical properties.
Western health beliefs: sharks and green-lipped mussels are used
to make extracts which are supposed to ward off cancer.
global climate change: the conversion of (cool by day) forests into
(warm by day) agricultural land and urbanisation, warms (by day) the atmosphere
and causes droughts. Emissions of hothouse gases blanket the atmosphere,
causing it to warm up.
rising sea level: due to the expansion of the water column and the
melting of polar and mountain ice caps.
sinking atolls: atolls were formed by living coral, swept together
by storm waves. As a result, they rise just above sea level. As the sea
level rises, so do the corals, but can they keep up, while producing enough
debris to raise the atolls? Scientists don't believe they can.
loss of beaches, mangroves and saltmarshes: as the sea level rises,
beaches move further inland, as do salt marshes and mangroves. But the
land is occupied by people, and there is no room to move. Many will disappear.
warming seas: seas have an enormous inertia to warming, and heat
moves downward only reluctantly. As a consequence, surface waters will
warm up much sooner than the deep sea.
coral reef bleaching: warm water (combined with other stresses)
is blamed for coral bleaching and consequential death of corals. As seas
warm further, serious disturbance of coral reefs may result, resulting
in major ecosystem changes.
melting tundras: as the permanently frozen soils of the tundras
warm up, they start decomposing and could release vast quantities of nutrients
nutrient rain: see nutrient discharge.
ozone depletion: an increase of the level of ultraviolet radiation
could affect the plankton ecosystems close to the ocean surface. One of
the main plankton upwellings is along Antarctica, precisely where the ozone
(over) exploitation: The seas have suffered
major damage from overfishing, resulting in the collapse of nearly alll
major finfisheries. It also caused disruption of social structure among
whaling/sealing: although whaling is by no means as intensive as
it once was, and all the great whales enjoy protection, the large species,
already hunted to below survival levels, are not recovering. The small
minke whale has taken over, being more than eight times more numerous than
a century ago.
Caribbean monk seal: hunted to extinction. Also Steller's sea cow
and great Auk
Hawaiian monk seal:
Hookers sea lion;
fishing: At least 80% of commercially important
marine species live within 300km off the coast. The USA EEZ contains 20%
of the world's fisheries resources! Nearly 70% of fish species are over-fished,
fully exploited or depleted. Global catch is being sustained only by increased
fishing at lower trophic levels, and a higher subsidy from fossil energy.
Peru anchovy fishery lost 7.5 Mt (drop from 9.5 to 1.5 megaton) or 80%
of its catch potential due to overfishing. FAO estimated sustainable level
Driftnet fishing: has been halted in the South Pacific, but is rife in
the North Pacific and Atlantic. 'Walls of death' of hundreds of miles catch
anything large enough to be ensnared. Designed to catch tuna, they also
San Francisco sardine fishery collapsed in 1947
Canada's West Coast Coho salmon fishery in the Columbia River collapsed
by 90% not only because of overfishing, but also because of pollution and
habitat destruction (dams). It is now completely protected. Salmon fish
farmers, fighting to save their fish from fatal algal blooms, have screened
their pens, and pump water from the deep into them. Halibut have disappeared
from southern waters. Stocks of lingcod and red snapper have crashed too.
Sea urchin harvest declined 90%. Overall fisheries in the Strait of Georgia
have declined 50%. Fletcher Challenge's Crofton pulp mill has pollluted
a large sea area with dioxins, although closed for 20 years. Seafood, particularly
crabs, caught there is poisonous to humans. Abalone stocks are endangered
and closed to fishing. The ground fishery on Georges Bank has collapsed
and 30% has been closed to let stocks recover.
USA: Gulf of Maine fishery collapse. Stocks of Pacific ocean perch
alutus) have not recovered from 90% decline in the 1960s. Bocacio (Sebastes
oaucispinis) are now regarded as critically endangered. Many species
of rockfish have been fished to critical levels.
coral reef fish: nassau groper, jewfish in Carribbean, Gulf of Mexico,
Atlantic virtually disappeared.
oyster: in Chesapeake Bay USA, declined by 95%.
white abalone: The California abalone fishery (5 species) has collapsed,
and the red urchin fishery has become over exploited.
giant clams (Tridacna gigas): fished to near extinction on most coral reefs:
Fiji, Guam, New Caledonia, Northern Marianas and more. It is now a protected
species, but protection is nearly impossible to enforce.
turtles: return to shore to lay their eggs. Most turtles under threat.
by-catch/ incidental catch: unwanted catches
affect young fish of commercial species and many other species. Dolphins
(everywhere), seals, sea lions, small-toothed sawfish (USA), sharks. Entanglement
in fishing nets (set nets, pelagic and bottom-set) and longlines. Old fish
species are caught at the same rate as target fish, which affects their
populations severely. 50-300% of the trawl catch is bycatch.
ghost-fishing: lost fishing nets, pots and baited lines keep fishing,
often for many years, catching mainly old animals, a short-circuit of the
shrimping: shrimp are caught by shallow water trawling with fine-meshed
nets. All species are caught. Only fast fish escape. A large part (200-400%)
is bycatch. Coastal benthos is destroyed.
aquarium trade: small fish are caught on reefs, with cyanide. The
aquarium trade threatens many species, including lower animals like shells,
worms and corals.
marine farming/ mariculture: the sea is used for its water quality,
while food is supplied in unnatural quantities. As a result, the seabottom
becomes covered in faecal pellets and food remains, threatening the fish
stock with disease. Shrimp farming in the tropics has suffered a serious
decline because of this. Salmon farms much less so. The farming of oysters,
mussels and scallops has met with more success. These are not fed artificially,
but filter the plankton from the water. However, they produce faecal pellets
and pseudofaeces (the discarded sediment) which can cause problems.
destructive fishing: in many places, particularly
in poor nations, destructive fishing is widely used. Note in this context
that many forms of trawling are also destructive: shrimping, scalloping,
deep sea trawls, etc.
blast fishing: using commercial, military or home made explosives.
Significant problem to coral reefs in Malaysia, Thailand, Indonesia, Philippines.
poison fishing: fish for the aquarium trade are teased out of their
holes and shelters by means of poison. It causes death to sensitive species,
and produces a high degree of unwanted 'by-catch'.
mining: mining the seabed for minerals destroys benthic communities.
In the course of mining, many spills occur at various times of the planned
process. Unplanned spills occur too.
competition for food: as people catch more and more effectively,
stocks become depleted and other organisms who are not as efficient as
people, hunger and die.
Dolphins stressed: dolphins and toothed whales worldwide are under stress
from having to work longer hours and play less.
soil erosion: the mud from soil erosion is
one of the largest threats to the marine environment, in places far exceeding
that of exploitation. Often exploitation is blamed for a fish stock collapse,
where spoiled water was responsible for spawning, breeding and recruitment
sediment: sediment smothers water-breathing and filter-feeding organisms.
Sediment in the water causes loss of light, so that algae can no longer
live at depth. Sediment clogs the gills of water-breathing animals, including
phyto and zoo plankton. Fish larvae are sensitive to the quality of the
loss of coral reefs: Most coastal reefs have degraded severely due
to run-off from the land. Of a total of 600,000km2 of coral reef, about
10% have been eroded beyond recovery.
Great Barrier Reef: only recently have scientists acknowledged that
the entire barrier reef is under severe threat from the rivers nearby.
Between the reef and the mainland (Australia), a sheltered 'lagoon' exists,
where deposited mud remains forever. Recently, the rains here have become
many times more severe, and with it the mud from rivers. Sediment plumes
fan out over the entire reef after a large storm, changing the marine ecosystems,
while soiling the bottom. Due to the sheltering nature of reefs, sediments
are not easily stirred by waves and washed away by currents. The GBR has
lost 60% of all life.
coastal habitats: mud from rivers stays suspended due to the action
of waves, and once settled on the bottom, is suspended again with each
period of swell. It causes the loss of algae (due to shading) and filter
feeders such as sponges and seasquirts, due to clogging of their pores
and gills. Combined with fine algae, mud tenaciously sticks to organisms
and substrate, preventing larvae from settling, and killing a wide range
eroding beaches: 70% of the world's sandy beaches are eroding. Beach
renourishment costs US$60 million per mile, needs to be redone every 50
nutrients: see below. As mud interacts with sea water and bottom
organisms, it releases the nutrients that were attached to its clay bonds.
When subsoil clays erode, the nutrients destined for future forests are
lost, causing the release of high concentrations of nutrients.
reclamation: the direct loss of marine habitat, usually in estuaries,
by housing development, tourist facilities, causeways. The habitats most
affected are saltmarsh and mangrove, and to some extent eelgrass.
marine farming: people want their marine farms close to home, and
modify the seashore accordingly.
mangroves: are threatened for fire wood, being converted into
shrimp farms, and infilled for housing and industry, airports, etc. Mangroves
often provide the nursery grounds of young benthic and pelagic fish.
seagrass meadows: are an important habitat and food source for many
Johnson's sea grass: USA
estuary: estuaries are productive places because of the nutrient
runoff from the land, and the repeated inflow of fresh seawater. Inside
estuaries the temperature rises by several degrees, which promotes productivity.
Phytoplankton responds favourably to estuarine conditions.
saltmarsh/mangrove: are often feeding grounds for the juveniles
of marine species, which are sensitive to pollution.
USA lost over 50% of original saltmarsh and mangroves.
seabed/ trawling: trawling causes massive damage to the sea bed.
In places, each part of the seabed is trawled 3-10 times a year. Where
rocky outcrops are found, the seabed fauna is long-lived and very sensitive
to disturbance (sponges, corals, hydroids, bryozoa). Such habitat is found
around sea mounts, and where the bottom slopes steeply. As fish becomes
harder to catch, trawling effort is going up.
propeller scouring: the number of recreational motor boats has risen
dramatically in the past 40 years. Many marine organisms living close to
the surface are affected, particularly those which grow old, like whales.
Dolphins are agile and able to dodge fast speed boats, but shags, penguins,
stingrays, are often just too slow. In Florida, manatees are killed by
disruption of family- and social structure: marine creatures live
in social structures, as do land animals. The way we fish creates havoc
to such structures. Many marine fish mate up for life. The loss of one
amounts effectively to the loss of two, when it comes to reproduction.
It particularly affects old fish, which are the most prolific and effective
species diversity: little is known about
biodiversity in the seas.
loss of endemic species: little is known.
introduced exotic species: exotic species can travel on the hulls
of ships or inside their ballast water. Those that were successful, have
created havoc in various places.
chemical pollution: 10,000 of 65,000 synthetic chemicals are used
regularly. Many accumulate in tissues of plants and animals. Some can cause
cancer or disrupt endocrine systems. Stunted growth, missing spiness, scale
disorientation, jaw deformities, disrupted immune systems, recruitment
failure, chromosome abnormalities. Contaminants concentrate (up to 1000
times) in the sea surface layer, where fish larvae also concentrate (foodchain
oil: from ships, transport, pipelines, storage tanks. Oil floats
on the surface, where it does most harm. As water moves into and out of
estuaries, and up and down with the tides, it leaves an oil slick behind.
In this manner, oil can soil an unexpectedly large area. Species living
within its reach are all very sensitive.
smoke: CO2, contaminants, nutrients. See nutrient discharge.
40% of Europe's coastal pollution comes from the air.
transport: cars leave rubber, oil and lead behind on roads and their
margins. Rains wash these into the sea.
industry: PCB, DDT
contamination of sediment: sediments attract and bind pollutants such as
agriculture: USA 135,000 tonnes pesticides applied annually, which
incineration: under high temperatures, dioxin forms from plastics
like PVC. It is a highly potent poison, which affects animal reproduction
and eggs in minute concentrations.
blackfooted albatros on Midway Atoll USA,
nutrient discharge: vastly more nutrients
reach the sea today than a century ago, from agricultural runoff, industry,
refineries and the burning of fossil fuels in energy generation and transport.
They reach the sea by river or through the atmosphere. In the sea, the
nutrients feed the plankton which blooms excessively, particularly in coastal
harmful algal blooms (HAB): loss of light, suffocation, toxicity.
They are increasing in frequence and severity. Many bloom species produce
virulent toxins that accumulate or kill outright.
Amnesiac Shellfish Poisoning (ASP): Pfiesteria piscicida kills fish.
(N Carolina, Maryland, Virginia); causes memory loss in people.
Paralytic Shelfish Poisoning (PSP): domoic acid poisoned many people
in Canada and west coast USA 1987, 1991. Accumulates in various shellfish
and crustaceans: razor shells, Dungeness crabs, mussels (NZ), oysters,
Diurethic Shellfish Poisoning (DSP):
nuisance plankton blooms: not of direct consequece to people. Water
may become discoloured or smelly. Beaches are closed.
Bluff oysters, mussel culture in New Zealand severely threatened.
Pfiesteria piscida, cell from hell: predator microbe has 24 life stages,
from green plant to predator. Dangerous to humans too: loss of consciousness,
memory loss, fatigue, vomiting, diarrhea, muscle contractions, respiratory
Florida: In 1994 130 manatees died. In 1995 more than 300 endangered manatees
killed by a red tide of dinoflagellates. 5% of Florida manatees 1996. In
1999 red tides struck again, causing fish kills and eye and respiratory
irritations for beachgoers. In 2002 305 died. In 2003 120 died in 4 months,
all from poisonous plankton blooms (PSP suspected).
Texas: In 1997 a red tide killed millions of fish and sent tourists fleeing
with hacking coughs.
California: in 1998, 400 sea lions died in Monterrey Bay after eating
anchovies that had consumed toxic algae.
New Zealand: in 1993-1997 shellfish fisheries were closed repeatedly. Several
people got ill from walking over a beach.
eutrophication: nutrients create plankton
blooms. When organisms die in deeper layers, all oxygen is used up in their
decomposition. The environment becomes anoxic and toxic. Eutrophication
events are becoming more frequent and more serious (Gulf of Mexico, north-east
dead zones: oxygen-lacking and dead-looking zones in the Gulf of
Mexico, lasting 8 months each year while covering a million ha (7700sqMi).
Thought to be caused by nutrients from the Mississippi River.
suffocating blooms: many diatoms form strings that can clog the
gills of water breathing animals like clams, seasquirts and sponges. Such
strings accumulate 'snot' from deceased jellyfish, and form oceanic 'snow',
which clogs gills and breathing pores.
shading blooms: dense plankton blooms which last long enough to
reduce the penetration of sunlight, thereby killing submerged vegetation
such as eelgrass and macroalgae.
USA: 7000 beach closures/year.
debris pollution: plastics, fish nets, garbage
dumping from ships,
noise pollution: ships produce high levels of noise. It can affect
the navigation systems of whales, and their ability to catch food. Cetaceans
may become deaf over their life span, in the same way humans do. After
a working life, most Western people are 15-20dB deaf (6-10 times impaired).
Present-day city youths reach that level much earlier in life, due to their
exposure to loud music.
transport: transport of goods and people is intensifying
ship strikes: large species hit by ships: whales, manatees.
ballast water: to weigh down empty cargo ships, they take in ballast
water. Larvae can the disperse far afield. Yearly about 43 million tonnes
of ballast water is dumped into US coastal environments.
150 introduced (non-indigenous) species in San Francisco Bay. Chinese clam
exceeds 10,000 animals per square metre.
long-term unspecific decline: the causes
are not known, but species are seen in continuous decline. Some decline
precipitates suddenly. Reproduction failure is often not noticed until
fish stocks suddenly decline from natural causes.
sea birds: kittiwakes, murres, red-throated loons, 8 species of
sea ducklings, spectacled eiders. Numerous Alaskan wildlife species.
coral reefs: declining and becoming sick everywhere. Florida Keys
severely affected. Black band, white band, aspergillus disieases; coral
plankton: Off southern California the abundance of zooplankton --
the food source for most marine life -- has decreased 80% since 1951
Black Sea: The Black Sea is spiralling into decline as a result
of chronic overfishing, high levels of pollution and the devastating impacts
of alien species. During the past 20 years around a third of fish
stocks have been lost. The Black Sea is bordered by 6 nations, and 4 major
rivers flow into it.
diseases: are spreading and increasing
in number. Sudden mass mortalities.
fibropapilloma disease: turtles Florida & Hawaii, Caribbean. Also leatherback
turtles in Florida.
canine distemper type of virus: skin lesions in bottlenose dolphins US
east coast 1987.
cancer: in 18% of stranded sea lions off California.
coral diseases: elliptical star coral Florida Keys,
eelgrass wasting disease: USA northesast coast, Australia,