Ecology
• Relations between organisms and their environment and between
organisms reciprocally (classical conception – Ernst Heackel, german
ecologist, 1866, human as a species)
• Human Environment – the part of Earth, which is used by human and
which human affects
• Functional relations in nature, „Nature Economy“ Science
• Configuration of organisms and environment relations Environmental
science (E.P.Odum, americn ecologist, 1977).
• Ecosystem Science – biotic and abiotic systems relations (Paul
Duvigneaud: Ekologická syntéza, 1980)
Present day view:
Environmental aspects, Social aspects, Economy aspects, Biomedicine
aspects....
Human Ecology
Human ecology is an academic discipline that deals
with the relationship between humans and their natural,
social and created environments. Human ecology
investigates how humans and human societies interact
with nature and with their environment.
New discipline of antropology – investigates all
environment components, which influence individual and
human population
The aim is protection of population as well as of
ecosystem
Human Ecology
• Man can´t understand mechanisms and powers of nature
and thus disturb its basic cycles and systems (cycles of N,
C, water, energy….)
• Earth can´t bear all human interventions, it can´t adapt to
it as quickly
• Comes out from classical disciplines – population
dynamics, ecosystems and its energy cycles, society
behaviour, biomass production, world´s bioms
Human ecology - history
• Early agriculture (Eufrat, Tigris) – irrigation caused salinization and
barleycorn couldn´t be grown
• Deforestation in Greece and subsequent errosion
• XIX . Century – human population studies - demogrphy (Essay on
Population from Malthus)
• XX. centruy - Ch.Elton - Animal ecology (1927) – biological factors,
that affects human population
• Mathematical modeling of limiting factors for various
population in various ecosystems. New methods and
preparations for worse situations (soil errosion,
ecosystem pollution, rain forest devastation,….)
Environment and medical sciences
• Environment (natural and artificial) influences state of
health to a large degree
• Individual – from the begining of pregnancy over all live,
affects the quality and lenght of life
• Population – long term selecting of genotypes (special
blood diseases,…)
• Abiotic factors – radiation, clime, chemical matters, soil
condition, water quality, air pollution
• Biotic factors – food quality and quantity, infections.
• Social factors – welfare, stress, possibility/impossibility of
regulation of life quality (lifestyle)
Environment and medical sciences
• The patient comes to doctor as a mirror of his life
environment (with his inherited and non-inherited
diseases and characteristic).
• Doctor´s interest in patient environment results from his
interest of patient and population health
• Technocrats and ekonomists – the only one argument is
profit
• Doctors and Environmentalists – argument is also the
health and welfare and nature itself.
Environment and medical
Sciences - Epidemiology
• Disease – outcome of human being
(endogenic factor) and environmental
factors (exogenic)
• Zoonozis – infectious disease (from
animal to man) Ebola, Yellow fever,
Monkey smallpox, Rabies, Hanta virus,
Nipah, Marburg fever, variety of
influenza,....
Kalong – carrier of Hendra virus (1994),
Ebola (1996), Nipah, SARS
Toxicology
• Branch of knowledge, which studies toxic effects of
xenobiotics (introduced chemical compound) or
their mixtures on living organisms.
• Disease – outcome of human being (endogenic
factor) and environmental factors (exogenic)
• Exposure – contact of chemical matter and living organism,
when chemical matter spread into organism
• Toxikinetics
• Toxidynamics
Toxicology
• Xenobiotics – synthetical and natural
• Plant, animal (snake, insect, ….), bacterial
• By affected organs - neurotoxins,
hepatotoxins, haemotoxins, myotoxins….
Toxicology
• Dosis Letalis Media LD50 – matter concentration, when
50% of tested organisms die in 24 hours.
• Tempus Effectivum Medium ET50 – time from entering
to effect proving at 50% of tested organisms
• Tempus Letale Medium LT50 – time from entering to
death of 50% of tested organisms.
• Accute exposure (max 4 hours)
• Repeated exposure
• 1. Subaccute toxicity (4 weeks)
2. Subchronic toxicity (1 – 3 months)
3. Chronic toxicity – longer than 3
months
Toxicity
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Selective toxicity (species, organ)
Local toxicity
System toxicity
Toxicity Tests (TT)
Acute toxicity tests
Alergy
Only 20-25% of newborn defects is caused by genetics,
others are in combination with environmental
conditions
Abiotic and Biotic Factors of Environment
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Hydrosphere (water)
Atmosphere (air)
Paedosphere (soil)
Biosphere
Baby = 75% water
Biosphere - World´s forests
Forest functions
Deforestation
- Forests cover a third of our planet's dry land.
-They provide raw materials, maintain biodiversity, protect land and
water resources, and play a role in climate change mitigation.
- Forests are heavily exploited, but important efforts are being made to
use and manage them more sustainably.
but 60 000 km2 (an area roughly the size of Ireland) continue to be lost
or modified by logging or other human interventions each year.
-When forests grow, carbon is removed from the atmosphere and
absorbed in wood, leaves and soil.
- world’s forest ecosystems are estimated to store more carbon than the
entire atmosphere.
Biodiversity
• Biodiversity reflects the number, variety and variability of
living organisms as well as how these change from one
location to another and over time. It includes diversity
within species, between species, and among ecosystems, in
sum the diversity of all life on earth.
• The impact of humans on the natural environment is
significant and growing: changes in biodiversity have been
more rapid in the past 50 years than at any time before in
human history.
• Over the past few hundred years, it is estimated that
humans have been responsible for up to a thousand times
more extinctions than the natural rate
Biodiversity
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Three levels of diversity:
Ecosystems (tropical rain forrest, sea,....)
Species
Genetical diversity
• Two types of conservation:
• Area protection (National parks, Protected areas,....)
• Species protection (Restriction or prohibition of
hunting or marketing, special areas and programes,
ZOOs,....)
Biodiversity
loss
Biodiversity loss
Five major threats to biodiversity
• Invasive alien species
• Climate change
• Nutrient loading and pollution
• Habitat change
• Overexploitation
Biodiversity for Medicine