AQU127 – AQUATIC ECOLOGY AND ENVIRONMENT
CHAPTER 1 – INTRODUCTION OF AQUATIC ECOLOGY
i. Ecological terms
ii. Scope of ecological research
iii. Functions of aquatic system
iv. Ecological functions based on thermodynamics
v. Ecological principles
vi. Living organisms in aquatic environment
1. Definition and component
- The study of the interactions among organisms and between organisms and
their abiotic environment
- Enormously complex:
i. Organisms affected by environment, but their activities also can change
the environment
ii. E.g., photosynthesis by phytoplankton, nutrient cycling
- 2 components: AQUATIC & ECOLOGY
- Aquatic: 3 major types
i. Freshwater
ii. Estuarine
iii. Marine
- Study of aquatic ecosystem:
i. Limnology: mostly about freshwater
ii. Oceanography: mostly on marine, sometimes include brackish
2. Scope of ecological research
- Organismal ecology: how an organism’s structure, physiology, behaviour meet
the challenges posed by environment (exp: how do sharks select a mate)
- Population ecology: analyses factors that affect population size and why it
changes through time (exp: what environmental factors affect the reproduction
rate of deer)
- Community ecology: examines how interactions between species (predation &
competition) affect community structure and organization (exp: what factors
influence the diversity of species that make up a forest)
- Ecosystem ecology: emphasizes on energy flow and chemical cycling between
organisms and the environment (exp: what factors control photosynthetic
productivity in a temperate grassland ecosystem)
- Landscape ecology: studies on the factors controlling exchanges of energy,
materials, and organisms across multiple ecosystems (exp: what extent do the
riparian trees serve as corridors of dispersal for animal)
, - Global ecology: examines how the regional exchange of energy and materials
influences the functioning and distribution of organisms across the biosphere
(exp: how does ocean circulation affect the global distribution of crustaceans)
3. Biomes: major ecosystem spread over a wide geographic area, and characterized by
certain types of flora and fauna
4. Freshwater biomes: large lakes, large river deltas, polar freshwaters
5. Marine biomes: polar, temperate shelves and sea, tropical coral
6. 2 components:
i. Biotic – living environment
ii. Abiotic – non-living entities in the ecosystem
7. Aquatic ecosystem: ecosystem in a body of water, communities of organisms are
dependent on each other and on their environment live
8. Function of aquatic ecosystem:
i. Recycle nutrient
ii. Purify water
iii. Attenuate flood
iv. Recharge ground water
v. Provide habitat for aquatic life
vi. Tourism industry (human recreation)
9. Ecological concepts: general understandings about ecosystem, provide a foundation
for developing ecological principles
10. Key concepts in ecology:
i. Adaptation: organisms are adapted to their environments
ii. Thermodynamics: ecological systems function according to the law of
physics, particularly thermodynamics
iii. Physical controls: controls and influences the development of the biological
community and its population dynamics
iv. Community: dependent on a number on interspecies interactions
v. Alteration: human alter ecological processes
,11. Organisms are adapted to their environments:
- Crucial determinates of an organism’s habitat:
i. Water
ii. Soil
iii. Temperature
iv. O2 & CO2
v. Inorganic nutrients
vi. Osmotic potential
vii. Light
viii. Size of the organism
- Interlinked for all organisms:
i. Salt balance
ii. Water balance
iii. Nitrogen excretion
iv. Gas exchange
v. Temperature regulation
- Individual organisms try to maintain internal homeostasis in a variety of
parameters
12. Ecological system function according to The Laws of Physics -> Thermodynamics
- All ecosystems rely on the sun the energy
- Energy use in not 100% efficient, energy lost from ecosystems in the form of heat
- Nutrients can be cycled through an ecosystem
- Biomes are controlled by climatic factors, habitats by local irregularities of
topography, distribution of organisms determined by climatic factors &
topography
13. Thermodynamics:
- Definition: study of energy and its transformations
- System: 2 systems
i. Closed system – not exchange energy with surroundings
ii. Open system – exchanges energy with surroundings
- Laws of thermodynamics: 2 laws
i. First Law of Thermodynamics – energy cannot be created or destroyed; it
can transform from one form to another (Solar energy)
ii. Second Law of Thermodynamics – whenever energy is transformed,
there is a loss energy through the release of heat (food web, respiration,
movement in trophic levels)
, - Passage of energy through an ecosystem:
i. Producers – autotrophic plants
ii. Primary consumers – herbivores
iii. Secondary consumers – carnivores
iv. Decomposers
14. Energy flows (in=sunlight, out=heat)
i. Light energy falls on plants, part of it is transformed into chemical energy in
the plants
ii. Herbivores consume plants, chemical energy accumulated in plant products
convert to kinetic energy, degradation of energy will occur through heat
iii. Herbivores consumed by carnivores (secondary consumers) further
degradation will occur
iv. Chemical energy in dead organic will be used by decomposers, some will
release to environment (heat)
15. Food chain
- Shows a sequence of organisms, starting with producer, ending with top
consumer
- The food chain in an ecosystem is interconnected, can be shown ad a food web
CHAPTER 1 – INTRODUCTION OF AQUATIC ECOLOGY
i. Ecological terms
ii. Scope of ecological research
iii. Functions of aquatic system
iv. Ecological functions based on thermodynamics
v. Ecological principles
vi. Living organisms in aquatic environment
1. Definition and component
- The study of the interactions among organisms and between organisms and
their abiotic environment
- Enormously complex:
i. Organisms affected by environment, but their activities also can change
the environment
ii. E.g., photosynthesis by phytoplankton, nutrient cycling
- 2 components: AQUATIC & ECOLOGY
- Aquatic: 3 major types
i. Freshwater
ii. Estuarine
iii. Marine
- Study of aquatic ecosystem:
i. Limnology: mostly about freshwater
ii. Oceanography: mostly on marine, sometimes include brackish
2. Scope of ecological research
- Organismal ecology: how an organism’s structure, physiology, behaviour meet
the challenges posed by environment (exp: how do sharks select a mate)
- Population ecology: analyses factors that affect population size and why it
changes through time (exp: what environmental factors affect the reproduction
rate of deer)
- Community ecology: examines how interactions between species (predation &
competition) affect community structure and organization (exp: what factors
influence the diversity of species that make up a forest)
- Ecosystem ecology: emphasizes on energy flow and chemical cycling between
organisms and the environment (exp: what factors control photosynthetic
productivity in a temperate grassland ecosystem)
- Landscape ecology: studies on the factors controlling exchanges of energy,
materials, and organisms across multiple ecosystems (exp: what extent do the
riparian trees serve as corridors of dispersal for animal)
, - Global ecology: examines how the regional exchange of energy and materials
influences the functioning and distribution of organisms across the biosphere
(exp: how does ocean circulation affect the global distribution of crustaceans)
3. Biomes: major ecosystem spread over a wide geographic area, and characterized by
certain types of flora and fauna
4. Freshwater biomes: large lakes, large river deltas, polar freshwaters
5. Marine biomes: polar, temperate shelves and sea, tropical coral
6. 2 components:
i. Biotic – living environment
ii. Abiotic – non-living entities in the ecosystem
7. Aquatic ecosystem: ecosystem in a body of water, communities of organisms are
dependent on each other and on their environment live
8. Function of aquatic ecosystem:
i. Recycle nutrient
ii. Purify water
iii. Attenuate flood
iv. Recharge ground water
v. Provide habitat for aquatic life
vi. Tourism industry (human recreation)
9. Ecological concepts: general understandings about ecosystem, provide a foundation
for developing ecological principles
10. Key concepts in ecology:
i. Adaptation: organisms are adapted to their environments
ii. Thermodynamics: ecological systems function according to the law of
physics, particularly thermodynamics
iii. Physical controls: controls and influences the development of the biological
community and its population dynamics
iv. Community: dependent on a number on interspecies interactions
v. Alteration: human alter ecological processes
,11. Organisms are adapted to their environments:
- Crucial determinates of an organism’s habitat:
i. Water
ii. Soil
iii. Temperature
iv. O2 & CO2
v. Inorganic nutrients
vi. Osmotic potential
vii. Light
viii. Size of the organism
- Interlinked for all organisms:
i. Salt balance
ii. Water balance
iii. Nitrogen excretion
iv. Gas exchange
v. Temperature regulation
- Individual organisms try to maintain internal homeostasis in a variety of
parameters
12. Ecological system function according to The Laws of Physics -> Thermodynamics
- All ecosystems rely on the sun the energy
- Energy use in not 100% efficient, energy lost from ecosystems in the form of heat
- Nutrients can be cycled through an ecosystem
- Biomes are controlled by climatic factors, habitats by local irregularities of
topography, distribution of organisms determined by climatic factors &
topography
13. Thermodynamics:
- Definition: study of energy and its transformations
- System: 2 systems
i. Closed system – not exchange energy with surroundings
ii. Open system – exchanges energy with surroundings
- Laws of thermodynamics: 2 laws
i. First Law of Thermodynamics – energy cannot be created or destroyed; it
can transform from one form to another (Solar energy)
ii. Second Law of Thermodynamics – whenever energy is transformed,
there is a loss energy through the release of heat (food web, respiration,
movement in trophic levels)
, - Passage of energy through an ecosystem:
i. Producers – autotrophic plants
ii. Primary consumers – herbivores
iii. Secondary consumers – carnivores
iv. Decomposers
14. Energy flows (in=sunlight, out=heat)
i. Light energy falls on plants, part of it is transformed into chemical energy in
the plants
ii. Herbivores consume plants, chemical energy accumulated in plant products
convert to kinetic energy, degradation of energy will occur through heat
iii. Herbivores consumed by carnivores (secondary consumers) further
degradation will occur
iv. Chemical energy in dead organic will be used by decomposers, some will
release to environment (heat)
15. Food chain
- Shows a sequence of organisms, starting with producer, ending with top
consumer
- The food chain in an ecosystem is interconnected, can be shown ad a food web
