生态学复习要点

1、1复习要点复习要点第一章第一章 IntroductionIntroduction toto ecologyecology 生态学概述生态学概述What is ecology?Eeraction: action on each other;Organism：an animal, plant, human orany other living things;Environment: Physical environment and biotic environm

2、ent.Physical environment ： Comprising such things as temperature, wateravailability, wind speed, soil acidity);Physical environment can be natural or man-made. Mostly, it is a mix of thetwo.Questions:What is an urban physical environment? Natural or man-made?What are some of the major elements that

3、comprise the urban physicalenvironment?In what ways does the urban physical environment influence its residents?Biotic environment：Comprising any influences on an organism that are exerted by otherorganisms, including competition, predation, parasitism, and cooperation.Give some examples of the abov

4、e influences you observe in yoursurroundings.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 naturalenvironment in its true sense?What is urban ecology?the study o

5、f interactions between urban organisms and their environment.Urban organisms VS natural organisms:Urban environment VS natural environment:2UrbanorganismHuman beings (Demographic features)Animals (home-kept animals and wide animals)Micro-organism (bacteria and viruses)Plants ( flowers, grasses, tree

6、s)Human beings are the dominant species of urban organismsUrban environmentPhysical: Man-made elements (buildings, streets, infrastructures);Biotic: animals and plants (home kept such as petsgardens) and wild (birds,rats, mosquitoes)Size of your study in ecologyIndividualsPopulationsCommunitiesEcosy

7、stemsIndividualsAny single living thing. Study the response of individuals to theirenvironment;PopulationsThe total number of animals or plants of one species. Study species,population abundance, and population fluctuations;CommunitiesA mixture of populations of different species. Study the process

8、determiningtheir composition and structure.EcosystemsComprise the biotic community in conjunction with the associated complexof physical factors that characterize the physical environment.We study system components, biomass, energy flow, nutrient cycle, andsystem functions.Discussons:Discuss the fou

9、r levels of study in terms of urban ecology.Key issues:Definition of EcologyDefinition of urban ecologyFour levels of study in ecology3Four levels of study in urban ecologyHome work:Compare the natural environment with urban environment, and see whatdifferences they have.Prepare Chapter Two: Underst

10、anding Ecosystems.第二章第二章 EcosystemEcosystem andand energyenergy flowflow 生态系统与能量流动生态系统与能量流动What is an ecosystem?A defined space which includes plants, animals (organisms) and physicalinteractions.An ecosystem can be of any size depending on the communities to bestudied.Ecologists tend to think of ec

11、osystem in terms of energy flow, carbon flowor nutrient cyclesComponents of an EcosystemBiotical elements:1. Producers (plants, grass),2. Consumers (cows, rabbits, lions, tigers, and so on)3. decomposers (bacteria, and fungus);Non-biotical elements: Organic elements, non-organic elements andclimatic

12、 elements.Components of an ecosystem4Energy flowSome key words of ecosystemEcosystem 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 dest

13、royed.Second law: Every transformation results in a reduction of the freeenergy of the system.Transfer efficiency:Theproportion of net primary production that flows through trophiclevels ( 营养层营养层） depends on the transfer efficiencies in the way energy isused and passed from one step to the next.Ther

14、e are threecategories oftransfer efficiency:Consumption5Efficiency (CE), Assimilation Efficiency (AE), and Production Efficiency(PE).Disturbance and recovery:Disturbance: Interruption or interference that occurs sufficiently oftenfor it to have exerted some selection pressure on the species experien

15、cingit.Internal disturbance and external disturbanceEnergy flow through a community:The pathway of energy at different trophic levels for differentcommunities.From CE toAE to PE.Nutrient recycle:Water cycleCarbon cycleNitrogen cycleQestions:Where does the energy on the earth come? Where does the ene

16、rgy in acity 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 ofan ecosystem.Discussion:Discuss the components and energy flow of an urban ecosystem.第三章第三章 UrbanUrban ecosystemecosystem 城市生态系统城市生态系统What is urban？

17、Different Countries have different definitions;Three elements count in defining a city:1.Population2.Industry3.Municipation.U.S. definition:Urban: Populated regions with a density of 1600 people/km2or greater6and a minimum population of 2,500.Metropolitan: Those consist of a central city with a mini

18、mumpopulation of 50,000,the county in which at least 50% of the populationof the central city lives, and outlying counties with well-defined links tothe central county or counties based on commuting patterns.SouthAfrica definition:Urban:Built up areas, including vacant space within a proclaimed muni

19、cipalor local authorized boundariesGeneral DefinitionIdentifiable places with defined or fixed boundaries and a high densityof population.Chinas DefinitionThe capital of a province or a county with a population over 2,000, ofwhich more than 50% are urban registered residents. ( 1995)What is an urban

20、 ecosystem?Urban ecosystem models are based on the interaction of the social,biological ,and physical components of a city.Asimplified model of urban ecosystem中国学者对城市生态系统的定义中国学者对城市生态系统的定义城市生态系统城市生态系统(Urban Ecosystem)指的是城市空间范围内的居民与自然指的是城市空间范围内的居民与自然环境系统和人工建造的社会环境系统相互作用而形成的统环境系统和人工建造的社会环境系统相互作用而形成的统体体

21、， 属人工属人工生态系统生态系统。 （杨小波等，（杨小波等，2000）人、自然环境和社会环境是城市生态系统的三大组成部分。人、自然环境和社会环境是城市生态系统的三大组成部分。Human-beings （人）（人）人口数量（人口数量（populations)人口结构人口结构 (Population structures)空间分布空间分布 (Spatial distribution of populations)Natural environment自然环境系统包括大气、水体、土壤、岩石、矿产资源、太阳能等非自然环境系统包括大气、水体、土壤、岩石、矿产资源、太阳能等非生物系统和动物、植物、微生物等

22、生物系统；生物系统和动物、植物、微生物等生物系统；Natural environment consists of such non-biotical elements as air,water, soil, rocks, minerals, solar energy and biotical elements asanimals, plants, and micro-organisms.Social Environment （社会环境）（社会环境）社会环境系统包括人工建造的物质环境系统社会环境系统包括人工建造的物质环境系统(包括各类房屋建筑包括各类房屋建筑、道桥道桥及运输工具、供电、供能、通风

23、和市政管理设施及娱乐休闲设施等及运输工具、供电、供能、通风和市政管理设施及娱乐休闲设施等)和和7非物质环境系统非物质环境系统(包括城市经济包括城市经济、文化与群众组织系统文化与群众组织系统，社会服务系统社会服务系统、科学文化教育系统等科学文化教育系统等) (man-made physical elements and non-physicalelements)城市生态系统的组成结构城市生态系统的组成结构(structure of urban ecosys)中国生态学家马世骏教授指出中国生态学家马世骏教授指出： “城市生态系统是一个以人为中心的自城市生态系统是一个以人为中心的自然界、经济与社会的

24、复合人工生态系统然界、经济与社会的复合人工生态系统”第四章第四章 Ecological Succession 生态演替生态演替Ecological Successtion：Ecological succession, a fundamental concept in ecology, refers tomore-or-less predictable and orderly changes in the composition orstructure of an ecological community.Primary Succession：Begins in a place without

25、any soil, such as sides of volcanoes,Landslides,Flooding. It starts with the arrival of living things such aslichens （ 地 衣 ）（ 地 衣 ） that do not need soil to survive. They are calledPIONEER SPECIES.Explain the pregress of primary succession: (See class presentations)Secondary Succession:Begins in a p

26、lace that already has soil and was once the home of livingorganisms. It occurs faster and has different pioneer species than primarysuccession. Example:after forest fires.Colonization by Species:The process of arrival and habitation of alien species at a new site and theestablishment of a community.

27、Climax Community:The final or stable community in the process of ecological succession is theclimax community or climatic vegetation. It is self-perpetuating and inequilibrium with the physical habitat. There is no net annual accumulation of8organic matter in a climax community mostly. The annual pr

28、oduction isbalanced in such a community.第五章第五章 Biodiversity 生物多样性生物多样性What do you think biodiversity means?Biodiversity is the variety of life on Earth and the essential interdependenceof all living thingsThere are 3 components of biodiversity ：1. Diversity of genesChihuahuas, beagles, and rottweile

29、rs are all dogsbut theyre not the samebecause their genes are different.2. Diversity of speciesFor example, monkeys, dragonflies, and meadow beauties are all differentspecies3. Variety of ecosystemsPrairies, Ponds, and tropical rain forests are all ecosystems. Each one isdifferent, with its own set

30、of species living in it.Why should we protec biodiversity?1.Biodiversity has utilitarian ValueUtilitarian Value = the value something has as a means to anothers end.Utilitarian values include:GoodsServicesInformation2.Biodiversity can provide us different services.OxygenFoodClean WaterMedicine9Aesth

31、eticsIdeas3.Biodiversity is good for ecosystem stabilityMore diversified, more stable;Threats to biodiversity:Habitat destructionPollutionSpecies IntroductionsGlobal Climate ChangeExploitation第六章第六章Urban Population and Environment 城市人口与环境城市人口与环境Urbanization：Why do people want to live in cities?Urban

32、ization:The process of people moving from rural areas to the urbanareas.Developed Countries: over 70% of the population live in cities;China: 36% in 2004，and about 50% in 2011.Population structure：Age structure: young, mid, and oldSex structure: male and femalenationality structure: han and minoriti

33、esHousehold registration Structure: rural or urbanFamily structure: married or singleEducation: high, literate and illiterateEmployment: employed and unemployedEnvironment Problems in China： Water pollution Air pollution Solid wastes Acid rain Desertification10 Forestry reduction Resource shortage F

34、armland reduction Loss of bio-diversity Ozone damage Global warming Ongoing biotic pollution第七章第七章Ecosystem service 生态服务功能生态服务功能What is ecosystem service functions?Ecosystem service function isthe capacity of natural processes andcomponents to provide goods and services that satisfy human needs,dire

35、ctly or indirectly.Ecosystem provides a variety of products for human beings, andmaintains the functions of life-support system.What benefits a forest can bring us? moderate weather extremes and their impacts disperse seeds mitigate drought and floods protect people from the suns harmful ultraviolet

36、 rays cycle and move nutrients protect stream and river channels and coastal shores from erosion detoxify and decompose wastes control agricultural pests maintain biodiversity generate and preserve soils and renew their fertility contribute to climate stability purify the air and water regulate dise

37、ase carrying organisms pollinate crops and natural vegetationClassification of ecosystem services:11第八章第八章 Global climate change 全球气候变化全球气候变化What is climate change?Climate change is a change in the average weather or a change in thedistribution of weather events around an average (for example, great

38、er orfewer extreme weather events). Climate change may be limited to a specificregion, or may occur across the whole Earth (global warming or greenhouseeffect).What is Greenhouse effect?The greenhouse effect is a natural mechanism that retains the heat emittedfrom the earths surface. Climate change

39、is believed to be the result ofGreenhouse Effect.Consequence of global warming :a. More droughts and more flooding:When the weather gets warmer, evaporation from both land and seaincreases. This can cause drought in areas of the world where the increasedevaporation is not compensated for by more pre

40、cipitation. The extra watervapor in the atmosphere has to fall again as extra precipitation, which cancause flooding in other places in the world.12b. Less ice and snow:Glaciers are shrinking rapidly at present. The ice is melting faster. In areasthat are dependent on melt water from mountain areas,

41、 this can causedrought and a lack of drinking water. Up to a sixth of the worlds populationlives in areas that will be affected by this.c. More extreme weather incidents:The warmer climate will most probably cause more heatwaves, more casesof heavy rainfall and also possibly an increase in the number and/or severityof storms.d. Rising sea level:The sea level rises for two reasons. Partly because of the melting ice andsnow, and partly because of the thermal expansion of the sea. Thermalexpansion takes a long time, but even an increase in temperature