复习要点
第一章 Introduction to ecology
生态学概述
What is ecology?
Ecology is the study of interactions between organisms and their environment. interaction: action on each other;
Organism： an animal, plant, human or any other living things; Environment: Physical environment and biotic environment.
Physical environment ： Comprising such things as temperature, water availability, wind speed, soil acidity);
Physical environment can be natural or man-made. Mostly, it is a mix of the two. Questions:
What is an urban physical environment? Natural or man-made?
What are some of the major elements that comprise the urban physical environment? In what ways does the urban physical environment influence its residents?
Biotic environment ：
Comprising any influences on an organism that are exerted by other organisms, including competition, predation, parasitism, and cooperation.
Give some examples of the above influences you observe in your surroundings. Questions：
What are some of the biotic elements you observe in a city? How do they influence the human residents in the city?
Are all kinds of environments human-controlled ? Is there any natural environment in its true sense?
What is urban ecology?
the study of interactions between urban organisms and their environment. Urban organisms VS natural organisms:
Urban environment VS natural environment: Urba n orga nism
Huma n beings (Demographic features)
An imals (home-kept ani mals and wide an imals) Micro-orga nism (bacteria and viruses) Plants ( flowers, grasses, trees)
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Huma n beings are the dominant species of urba n orga ni sms Urba n en vir onment
Physical: Man-made eleme nts (build in gs, streets, i nfrastructures);
Biotic: an imals and pla nts (home kept such as pets\\garde ns) and wild (birds, rats, mosquitoes)
Size of your study in ecology In dividuals Populati ons Commun ities Ecosystems
In dividuals Any single living thing. Study the response of individuals to their en vir onment; Populati ons The total number of animals or plants of one species. Study species, population abundance, and population fluctuations;
Commun ities A mixture of populatio ns of differe nt species. Study the process determ ining their compositi on and structure. Ecosystems Comprise the biotic com mun ity in conj un cti on with the associated complex of physical factors that characterize the physical en vir onment.
We study system comp onen ts, biomass, en ergy flow, nu trie nt cycle, and system fun cti ons.
Discuss ons:
Discuss the four levels of study in terms of urban ecology. Key issues:
Definition of Ecology
Definition of urban ecology Four levels of study in ecology
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Four levels of study in urba n ecology Home work:
Compare the natural environment with urban environment, and see what differe nces they have.
Prepare Chapter Two: Un dersta nding Ecosystems. 第二章 Ecosystem and energy flow
生态系统与能量流动
What is an ecosystem?
*A defi ned space which in cludes pla nts, an imals (orga ni sms) and physical in teracti ons.
?An ecosystem can be of any size depending on the communities to be studied.
?Ecologists tend to thi nk of ecosystem in terms ofenergy flow carbon flow or nutrient cycles
Components of an Ecosystem ?Biotical eleme nts:
1. Producers (pla nts, grass),
2. Consumers (cows, rabbits, lions, tigers, and so on) 3. decomposers (bacteria, and fun gus);
?Non-biotical elements: Organic elements, non-organic elements and climatic eleme nts. Components of an ecosystem
r无生命成巧 无机物质
〔有机物质
'生产者（绿色植物） I生命成分^消费者
（动物） 还原者（微生物）
图2-1生态系统的组成 （据云南大学生
物系编＞ 19S3）
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Energy flow
Some key words of ecosystem
?Ecosystem and the laws of thermodynamics: ?Transfer efficiency:
?Disturbance and recovery:
?Energy flow through a community: ?Nutrient recycle:
Ecosystem and the laws of thermodynamics:
?First law: Energy can neither be created nor destroyed ?
?Second law: Every transformation results in a reduction of the free energy of the system ?
Transfer efficiency:
?The proportion of net primary production that flows through trophic levels （营养层）depends on the transfer efficiencies in the way energy is used and passed from one step to the next ?
?There are three categories of transfer efficiency: Consumption
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Efficiency (CE), Assimilation Efficiency (AE), and Production Efficiency (PE). Disturbance and recovery:
?Disturbance: Interruption or interference that occurs sufficiently often for it to have exerted some selection pressure on the species experiencing it. ?Internal disturbance and external disturbance Energy flow through a community:
?The pathway of energy at different trophic levels for different communities ? ?From CE to AE to PE. Nutrient recycle: ?Water cycle ?Carbon cycle ?Nitrogen cycle Qestions:
?Where does the energy on the earth come? Where does the energy in a city come? *Is an ecosystem open or closed?
?What is the balance of an ecosystem?
?Give an example to show how human activities destroy the balance of an ecosystem.
Discussion:
?Discuss the components and energy flow of an urban ecosystem.
第三章Urban ecosystem 城市生态系统
What is urban?
?Different Countries have different definitions; ?Three elements count in defining a city: *1. Population *2. Industry
?3.M unicipation. U.S. definition:
?Urban: Populated regions with a density of 1600 people/kmor greater and a minimum population of 2,500.
?Metropolitan: Those consist of a central city with a minimum population of
50,000,the county in which at least 50% of the population of the central city lives, and outlying counties with well-defined links to the central county or counties based on commuting patterns ? South Africa definition:
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生态学复习要点
