Lecture review on environmental science

1. Lecture Review in Environmental
Science
John Mark M. Mayor, M.A.Bio.Ed.

2. Description of the Planet Earth
• Our planet is completely isolated from
everything in the universe
• Its totally exposed to sunlight
• Life support system consists of communities of
organisms

3. Components of the Ecosystem
• Abiotic (nonliving)
– Solar radiation
– Atmosphere
– Ocean climate and fire
• Biotic (living)
– Producers/Autotrophs
– Consumers/Heterotrophs
– Decomposers

4. Definition of Terms
• Ecology – the study of the relationships
between organisms and their environment
• Ecosystem – an integrated unit consisting of a
community of organisms and the physical
environment
• Environment – the sum of external forces and
conditions acting an organism or community
of organisms

5. • Environmental Science - the study of the
interactions among physical, chemical and
biological components of the environment

6. Interactions
• Competition – occurs when two or more
individuals attempt to use the same essential
source
– Competetive exclusion principle (exclusion of another
as a result of interspecific competition)
• Predation – the consumption of one species, the
prey and the predator
– Coevolution (predator prey evolution)
– Pursuit (pelican and fish)
– Ambush (predators attracting preys)

7. Predator-Prey Interaction
• First Way – Warning Coloration Mimicry and
Cryptic Coloration
• Second Way – Chemical Defenses
• Third Way – Predator Satiation (young survival)
• Hunting Ability Adaptations – social hunting
(lions)
– Fangs (snakes)
– Webs (spiders)
– Speed (falcon and cheeths)

8. Symbiosis
• Association in which two species live together
in a close relationship
– Protocooperation (cattle and cattle egrets)
– Mutualism (clown fish and sea anemone, lichens,
legumes)
– Commensalism (epiphytes)
– Parasitism (pathogens)

9. Community
• Niche – ecological role and functioning
• Habitat – Local environment
• Ecotone – a transitional zone where two or
more communities meet

10. Succession
• A process of community development over period of
time
• Described in terms of changes in the species
composition
• Primary succession – the change in species over time in
a habitat that was not previously inhabited by
organisms
• Secondary succession – is the change in species
composition that takes place after some disturbance
removes the existing vegetation
• Climax community – progressed, stabled and persistent
community

11. 7 Environmental Principles
• Nature knows best (cyclic flow of nutrients in the
ecosystem)
• All forms of life are important (all organisms were
created by God to serve a purpose)
• Everything is related to everything else
(interaction of living and non-living things)
• Changes (linear-physical and biological evolution,
cyclic-seasons, random-catastrophic forces) Man-
Made (accelerated-siltation of lakes due to rapid
soil erosion, inhibited – incomplete development
of fetus, introduced- urban communities)

12. • Everything must go somewhere (waste
management)
• Finiteness of resources (limits of Earth’s
capacity)
• Nature is beautiful and we are stewards of
God’s Creation (man created in God’s image
and have dominion overall dominion overall
his creations)

13. Feeding Relationships
• Food Chain – occurrence of energy flow in
which energy from food passes from one
organism to another.
• Food Web – complex interconnected food
chains in an ecosystem
• Trophic levels – nourishment
• Persistence – synthetic pesticides and
industrial chemicals is a result of novel
chemical structures and it is hard to degrade

14. • Bioaccumulation – build up of toxins in an
organisms body
• Biological accumulation – increase of toxin
level as it passes through successive levels of
the food web

15. Biogeochemical Cycles
• Carbon Cycle
• Nitrogen Cycle – nitrogen fixation, nitrification
(conversion N2-NH3, assimilation (absorption
NH3, NH4, NO3), ammonification (conversion
N2 – NH3 and NH4) and denitrification
• Phosphorus Cycle
• Hydrologic Cycle

16. Biomes
• Large, relatively distinct terrestrial region that has
similar climate, soil, plants and animals regardless
where it occurs
• Terrestrial Biomes – tundra, taiga, temperate
rainforest, temperate deciduous forest,
temperate grassland, chaparral, desert, savanna
and tropical rainforest
• Aquatic Ecosystems –determined by salinity,
aquatic organisms plankton(free floating), nekton
(strong swimming organisms), Benthos (bottom
dwellers)

17. • Freshwater – streams and rivers, lakes and ponds,
wetlands, estuaries
• Marine Ecosystems – large and complex marine
environment divided into:
– Intertidal zone, shoreline area between low and high
tide
– Benthic environment, ocean floor
– Neritic province, open ocean with continental shelves,
ocean floor and shoreline
– Oceanic province, covers the deep ocean basin

18. Air Pollution
• Earth’s Atmosphere
– Thermosphere, above about 450 km down 80 km
– Mesosphere, down to 50 km
– Stratosphere, about 15-50 km above us
– Ozone, thin layer in the stratosphere
– Troposphere, bottom 15 km

19. Sources of Air Pollution
• Natural Sources
• Man-made Sources
• Stationary Industrial Plants
• Mobile Engine Driven Vehicles
• Pollutants, sulfur dioxide smog ; photochemical
(combustion engines); carbon oxides; carbon
monoxide; sulfur oxides, nitrogen oxides, volatile
organic compounds (CFC); tobacco smoke,
formaldehyde, forest fires smoke emissions

20. Water Pollution
• Water usability: farming, industry, human
health and life
• Water pollutants: bacteria, oxygen demanding
wastes, acids, salts, mercury and lead,
fertilizers, oil, gasoline, sediments, silt and
sediments

21. Sources of Energy
• Non-renewable – coal, oil and crude oil,
natural gas, nuclear (Japan, China, India,
Korea, Taiwan, Vietnam, Indonesia)
• Renewable – solar, geothermal, hydropower,
wind, biomass, wastes

22. Causes of damaged to forest
• By atmospheric agents
– Excessive high temperature - poisonous gas
– Low temperature - animals (man)
– Shortage of water - fungi
– Excess water - weeds
– Wind - fires
– Mechanical injuries - insects
– lightning

23. Global Issues and Concerns
• Deforestation - Algal Bloom
– uncontrolled exploitation) - Biodiversity Loss
– Subsistence Agriculture
– Logging
– Housing
• Global Warming -Hydrological Imbalance
• Ozone Depletion -
• Acid Precipitation

24. Sustainable Living and Development
• Principles of sustainable society
– Respect and care for the community of life
– Improve the quality of human life
– Conserve vitality and diversity
– Minimize depletion and non renewable resources
– Keep with Earth’s carrying capacity
– Change personal attitudes and practices
– Enable communities to care for their own
environment
– Integrated conservation
– Create a global alliance

25. • Environment Policy
– Energy
– Business
– Industry and commerce
– Human settlements
– Farm and range lands
– Freshwaters
– Coastal areas