Ecosystem & Energy Flow
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Transcript of Ecosystem & Energy Flow
12/03/2014
1
KA40803 - Advanced Environmental Engineering
Topic : Ecosystems and Energy Flows
By Dr. Nurmin [email protected]
Learning outcome
This topic will provide the learners with the ability to:• Explain ecosystem & its role and importance
to environmental engineer• Identify and analyze energy and material flows• Distinguish the Circulation of energy and
matter in human
• List out the meaning/definition of an ecosystem…
5-10 min
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• An ecosystem consists of the biological community that occurs in some locale, and the physical and chemical factors that make up its non-living or abiotic environment
http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/ecosystem/ecosystem.html
• An ecosystem is a community of living organisms (plants, animals and microbes) in conjunction with the nonliving components of their environment (things like air, water and mineral soil), interacting as a system
Tansley (1934); Molles (1999), p. 482; Chapin et al. (2002), p. 380; Schulze et al. (2005); p. 400; Gurevitchet al. (2006), p. 522; Smith & Smith 2012, p. G-5
Eco?• a prefix mostly relating to ecological or environmental termsSystem?• a set of connected things or parts forming a complex whole, in
particular.• a set of things working together as parts of a mechanism or an
interconnecting network.• a set of organs in the body with a common structure or
function.(physiology)• a group of related hardware units or programs or both, esp. when
dedicated to a single application. (computing)• a set of principles or procedures according to which something is
done; an organized scheme or method. (organization)
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Ecosystem processes
List the processes, and explain(at least one – provide your reference)*do make sure no duplication with other friends/team
Work in group (3-5) 10-15 min task
Write down and explain
10 mins+ 10 mins
• Study of plants, animals, and their physical environments – and how energy-materials behave in ecosystem
• Ecosystem → complex yet possible to be narrowed and linked to the role u are in. (ie. Engineers, Geologist, zoologist, scientists, etc)
Remarks!
STD PROJECT: PRESENTATION topic:TOPIC #1-Discuss two examples of ecosystems and explain the connection towards current global issues.
20 min
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STD PROJECT- Presentation on: TOPIC#2 Human activities impact on ecosystems and environment. Why we as engineers should care.
10 mins+ 10 mins
Environmental engineers need to consider the ecosystems impacted by designs-by incorporating the expertise of professionals in other disciplines
Black bear in south carolina
An example of a bear-proof trash can in Shenandoah national Park, USexample
Energy & material flows in ecosystem
• Inside ecosystem – both energy & materials flows with fundamental difference– Energy flow only in one direction– Material flow is cylndrical
[Nutrients] + CO2→ → → O2+ [high energy molecules]
All energy originates from sun (as light energy)
sunlight
Example in photosynthesis (simple way)
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An Example of a one-way flow of energy
Rate of energy extracted or decreasingAnd NOT recycled
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An Example of a nutrient flow through an ecosystem
Start with dead organic (also termed as detritus)
Produces compounds as ammonia etc
Stabilized or fully oxidized & forms as a more stable compounds
CO2 use by plants & others as nutrients
Plants then die or use by other
Formation of new plant tissue
3 types of microbial decomposers:• Aerobic• Anaerobic• facultative 5 min
think & answer
What are major properties?
[detritus]+O2→CO2+H2O+[nutrients][detritus]→CO2+CH4+H2S+NH3+….+[nutrients]
Facultative – use oxygen when available and also can use anaerobic reactions if not available
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The arrow shows how energy is received from the sun and flows through the system
Balance equation: [IN]=[OUT]
Human influence on ecosystem
(1) Effect of pesticides• Organic pesticides such as
DDT• Decomposed very slowly• Stored in fatty tissus of
animals – transferred through food chain
Biomagnified in the food chain
Data from Woodell, G.M et al, 1967, Science 156:821-824
Human influence on ecosystem
(2) Effect of nutrients on a lake• Model of lake shows the
producers (algae) receive energy from sun (photosysthesis) –produce biomass & oxygen
• Consumers: fish, plankton etc –use oxygen & produce CO2, transfer nutrients
• Decomposers: eg worms, microorganism also respire (use energy) & use oxygen & produce CO2
• When not in balance –eutrophication can be reversed
ALGAE
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Human influence on ecosystem
(3) Effect of organic wastes on a stream• Problem also due to oxygen
depletion• Water can hold only limited
amount of gas; amount of oxygen can be dissolved depends on :– water temp, atms pressure,
concentration of dissolved solids
Stream – flushed out compared to lake
Ref: Vesilind, Morgan, Heine; 2011
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Mechanism of re-aeration in natural streams (constant noted as k)
consume
If the rate of oxygen use> the dissolved oxygen level drop (cannot keep up with oxygen consumption)=Deficit (D)
Deficit (D) = saturation of oxygen in water (S)-Concentration of DO (C)
Unit mg/L
[IN]=[OUT]Qs+Qp=Q0
S=upstreamp=pollution source
0=downstream
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Human influence on ecosystem
(4) Effect of Design on an ecosystemRemodel & incorporate :• energy-efficient• Water-efficient• Environment-friendly
materials• Green and sustainable
design
Example?
5 min think & answer
Energy flows and balances
Flow of energy in the living ecosystem
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More example of energy flow occurrences
Energy is NEVER produced or consumed – but changed form
[Rate of energy IN] = [Rate of energy OUT]
The first law of thermodynamics: The total amount of energy in the universe can neither created nor destroyed, only exchanged.
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A power plant uses 1000 Mg of coal per dayThe energy value of the coal is 28,000 kJ/kgThe plant produces 2.8 x 10exp6 kWh of electricity each dayWhat is the efficiency of the power plant?
Try!(ans: eff=36%)
The Circulation of Matter and Energy
• Humans being will always seek to improve their quality of life, and without doubt, this will harm the environment.
• The Earth’s entire biosphere can be viewed as a single, self-regulating “body” as which will react to disturbances much as a human reacts to attack by disease - Gaia Hypothesis - (such as extreme weather)
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THANK YOU