1、 Population Regulation 種群種群調(diào)節(jié)調(diào)節(jié) Density-dependent regulation& Density-independent regulation Bionomic strategies of populations toward environmental changes Population Regulation 種群種群調(diào)節(jié)調(diào)節(jié) The population regulation is divided into two groups according to relationship between population size and p

2、opulation density : density-dependent regulation & density-independent regulation2Density-dependent factors Density-dependent factors(密度制密度制約約因素因素）： Biotic factors， including intra-specific regulation(種內(nèi)調(diào)節(jié)）, interspecific competition（種間競(jìng)爭(zhēng)），predation, parasitism, etc, vary with the population den

3、sity.34Density-dependent factorscompetitionpredation Density-independent factors : a biotic factorsWeather, temperature, moisture, sun-exposure, rainfall, etc5 The population of Yangtze alligator has decreased sharply due to water pollution and natural disasters such as drought, flood, etc.Density-i

4、ndependent factors6Density-independent factorsBionomic strategies toward environmental changes Bionomic strategies: the adaptation of a species or population to the environment conditions to survive. Species living in long-term, stable environment utilize the environment as evenly as possible. In qu

5、ickly appearing and subsiding environment , organisms are capable of finding advantageous surviving locations in time.7所謂生態(tài)對(duì)策（bionomic strategies）就是一個(gè)物種或一個(gè)種群在生存斗爭(zhēng)中對(duì)環(huán)境條件采取適應(yīng)的行為；在長(zhǎng)期穩(wěn)定的環(huán)境中生活的種群盡可能均勻地利用環(huán)境；在迅速出現(xiàn)隨后又消逝的環(huán)境中，生物能及時(shí)地尋找有利的繼續(xù)生存的地點(diǎn)。We could divide the creatures into two kinds of strategies: r-sel

6、ection &K-selection.8Bionomic strategies toward environmental changesr-selection: appearing in places where the climate is unstable, and unpredictable disasters always appear, such as frigid zone or arid zone, they live in an ecological empty place, free of the influences of density. In such env

7、ironment, the species density stay in growing stage below the K value, and we call it the r-selection, the corresponding strategy-r-strategy.9r-selection (unstable environments)r選擇：氣候不穩(wěn)定，難以預(yù)測(cè)的天災(zāi)多的地方，如寒帶或干旱地區(qū)，它們居于生態(tài)上的真空，沒(méi)有密度影響，沒(méi)有競(jìng)爭(zhēng)類(lèi)型。在這一環(huán)境中，種群密度處于K值以下的增長(zhǎng)段，稱(chēng)為r選擇，該類(lèi)適應(yīng)對(duì)策為r對(duì)策。r-selection (unstable enviro

8、nments) In unstable or unpredictable environments, r-selection predominates as the ability to reproduce quickly is crucial. There is little advantage in adaptations that permit successful competition with other organisms, because the environment is likely to change again. 10 K選擇：氣候穩(wěn)定，很少有難以預(yù)測(cè)的天災(zāi)的系統(tǒng)，如

9、熱帶雨林就屬于這種情況，它是生態(tài)飽和的系統(tǒng)，動(dòng)物密度很高，競(jìng)爭(zhēng)劇烈；在這一環(huán)境中，動(dòng)物種群數(shù)量達(dá)到或接近環(huán)境容納量水平，即與種群邏輯斯諦增長(zhǎng)模型的飽和度K值接近，因此稱(chēng)為K選擇，該類(lèi)適應(yīng)對(duì)策為K對(duì)策11K-selection: a system where the climate is stable, few unpredictable disasters appear, such as the tropical rain forest. An ecologically saturated system, with high animal density, severe competition

10、; in this environment, the animal density has reached or got near to the environmental capacity, that is to say close to the carrying capacity- K of Logistic Equation.K-selection (stable environments)K-selection (stable environments) In stable or predictable environments, K-selection predominates as

11、 the ability to compete successfully for limited resources is crucial and populations of K-selected organisms typically are very constant and close to the maximum that the environment can bear (unlike r-selected populations, where population sizes can change much more rapidly).12The theory of r/K se

12、lection(MacArthur1962) Important Logistic parameters: r & K r-selection: reproduction stratagem that is beneficial to increasing the intrinsic growth rate r. K-selection: reproduction stratagem that is beneficial to boosting the competitiveness.13Characteristics of r-selection(opportunistic) r-s

13、election: high fecundity, small body size, early maturity onset, short generation time, and the ability to disperse offspring widely. Organisms with r-selected traits range from bacteria and diatoms(硅藻屬), through insects and weeds, to various semelparous cephalopods（首足類(lèi)動(dòng)物） and mammals, especially sm

14、all rodents（嚙齒動(dòng)物）14Characteristics of K-selection(equilibrium) K-selection : large body size, long life expectancy, and the production of fewer offspring that require extensive parental care until they mature. Organisms with K-selected traits include large organisms such as elephants, trees, humans

15、and whales, but also smaller, long-lived organisms such as Arctic Terns15r-selection & K- selection17Summary of population regulation Actually, r/K selections are just two basic types of natural selection of organisms. In the same region, under the same ecological condition, we could find many d

16、ifferent types. Most species stay between these two types with one, some or most traits. Thus, it is more appropriate to view these two types as two continuously varying extremes.18實(shí)際上， r-K選擇只是有機(jī)體自然選擇的兩個(gè)基本類(lèi)型，在同一地區(qū)，同一生態(tài)條件下能找到很多不同的類(lèi)型，大多數(shù)物種則是以一個(gè)、幾個(gè)或大部分特征居于這兩個(gè)類(lèi)型之間，因此，將這兩個(gè)類(lèi)型看作是連續(xù)變化的兩個(gè)極端更為恰當(dāng)intra-specific

17、 relationship 種內(nèi)關(guān)系種內(nèi)關(guān)系 constellation effect 集群效集群效應(yīng)應(yīng)： Constellation effect is beneficial to the whole, improving the predation efficiency and defensive quality, promoting breeding, strengthening the learning efficiency. Only under the “smallest race principle “ could constellation effect appear.19In

18、tra-specific relationship 種內(nèi)關(guān)系種內(nèi)關(guān)系 constellation effect 集群效集群效應(yīng)應(yīng)： Alices principle Under certain conditions, when the population density is on a moderate degree, the population grow fastest-either too low or too high density would restrain the population growth. too small-dissatisfy the “smallest ra

19、ce principle”too large-contribute to “crowd phenomenon”20Intra-specific relationship 種內(nèi)關(guān)系種內(nèi)關(guān)系Intra-specific competition 種內(nèi)種內(nèi)競(jìng)競(jìng)爭(zhēng)爭(zhēng)： ： competition among individuals of the same species Scramble competition 資資源利用性源利用性競(jìng)競(jìng)爭(zhēng)爭(zhēng): growth and reproduction are depressed equally across individuals in a populationA

20、ll individuals receiving insufficient resources local extinction Contest competition 相互干涉性相互干涉性競(jìng)競(jìng)爭(zhēng)爭(zhēng): some individuals claim enough resources while denying others a shareA fraction of the population suffers. Successful competitors to sustain the population.21Inter-specific relationship種種間間關(guān)系關(guān)系 Inter-

21、specific relationship is the interaction of different species. It could be divided into three groups: Neutral interaction Positive interaction: including commensalism 偏利共生,original cooperation原始協(xié)作, mutualism互利共生 negative interaction: including competition, predation, parasitism, amensalism 偏害共棲2223A

22、dvantageous, detrimental , no interest effect : +， -，0Interaction typesS 1S 2traitsneutral interactionno effect from each other contest competitionone inhibits the other directlyscramble competitionindirect inhibition under limited sourcesamensalisms1 inhibited, s2 no effect. parasitism+infestor s1,

23、 usually smaller than host s2predation+predator s1, usually larger than prey s2commensalism+beneficial to s1, no effect for host s2original cooperaction+beneficial to both, but not necessarymutualism +necessarily beneficial to bothInter-specific competition: two or more species utilize and compete f

24、or the same resources. The result of the competition is usually asymmetric Gauses hypothesis: when two species utilize and compete for the same resource and space, the more similar they are, the more their niches overlap, thus the severer the competition.24Inter-specific relationship種種間間關(guān)系關(guān)系Parameci

25、um aurelia& Paramecium caudatum experiment雙小核草履蟲(chóng)和大草履蟲(chóng)試驗(yàn)25Inter-specific relationship種種間間關(guān)系關(guān)系Competition exclusion principle競(jìng)競(jìng)爭(zhēng)排斥原理爭(zhēng)排斥原理 In a stable environment, two or more species, limited by resources, sharing the same way to utilize resources, could not coexist in the long term, i.e. complete

26、 competitors could not survive together. 26在一個(gè)穩(wěn)定的環(huán)境內(nèi)，兩個(gè)以上受資源限制的、但具有相同資源利用方式的種，不能長(zhǎng)期共存在一起，也即完全的競(jìng)爭(zhēng)者不能共存。Inter-specific relationship種種間間關(guān)系關(guān)系Competition typesnScramble competition資資源利用性源利用性競(jìng)競(jìng)爭(zhēng)爭(zhēng): only through consuming the limited resources, without direct interaction . .nContest competition相互干涉性相互干涉性競(jìng)競(jìng)爭(zhēng)爭(zhēng)

27、: through direct organism interaction.27Inter-specific relationship種種間間關(guān)系關(guān)系Competition traits The asymmetry of the competition result. The competition for one resource could influence the competition for another resource.28（1 1）競(jìng)爭(zhēng)結(jié)果的不對(duì)稱(chēng)；）競(jìng)爭(zhēng)結(jié)果的不對(duì)稱(chēng)；（2 2）對(duì)一種資源的競(jìng)爭(zhēng)能影響對(duì)另一種資源的競(jìng)爭(zhēng)結(jié)果。）對(duì)一種資源的競(jìng)爭(zhēng)能影響對(duì)另一種資源的競(jìng)爭(zhēng)結(jié)果。I

28、nter-specific relationship種種間間關(guān)系關(guān)系Lotha-Volterra ModelSPECIES 1：dN1/dt=r1N1（1-N1/K1）SPECIES 2：dN2/dt=r2N2（1-N2/K2）SPECIES 1：dN1/dt=r1N1 （K1- N1 - N2） /K1SPECIES 2：dN2/dt=r2N2 （K2- N2 - N1） /K2（、 : competition coefficient of s1 and s2 ）29Inter-specific relationship種種間間關(guān)系關(guān)系30K1 K2 / ， ，K2 K1 /： ： N1取取

29、勝勝, N2滅滅亡亡在在K2， ，K2 / ， ， K1 /， ， K1 這塊這塊面面積積內(nèi)，種群內(nèi)，種群2已已經(jīng)經(jīng)超超過(guò)過(guò)最最大容大容納納量而不能增量而不能增長(zhǎng)長(zhǎng)，而種群，而種群1仍能仍能繼續(xù)繼續(xù)增增長(zhǎng)長(zhǎng)， ，N1取取勝勝， ，N2被排被排擠擠掉掉dN1/dt=0K1 /K2K1K2 / N1=K1dN2/dt=031N2K2K2K1/K1K2 / dN1/dt=0dN2/dt=0K1 K1 /： ： N2取取勝勝， ，N1 滅滅亡亡由于在由于在K2， ，K2 / ， ， K1， ， K1 /這塊這塊面面積積內(nèi)，種群內(nèi)，種群1已已經(jīng)經(jīng)超超過(guò)過(guò)最大容最大容納納量而不能增量而不能增長(zhǎng)長(zhǎng)，而種群，

30、而種群2仍能仍能繼續(xù)繼續(xù)增增長(zhǎng)長(zhǎng)， ， N2取取勝勝， ， N1被排被排擠擠掉。掉。32K2K1/K1K2 / dN1/dt=0dN2/dt=0l K1 K2 / ， ，K2K2 / ， ，K2 K1 /:不不穩(wěn)穩(wěn)定共存定共存l在三角形在三角形K1 E K2 / 中，種群中，種群2不能增不能增長(zhǎng)長(zhǎng)，種群，種群1繼繼續(xù)續(xù)增增長(zhǎng)長(zhǎng)， ， 三角形三角形K2EK1 /中，種群中，種群1不能增不能增長(zhǎng)長(zhǎng)，種，種群群2繼續(xù)繼續(xù)增增長(zhǎng)長(zhǎng)。 。N2和和N1出出現(xiàn)現(xiàn)不不穩(wěn)穩(wěn)定的平衡點(diǎn)。定的平衡點(diǎn)。(c) 2001 W.H. Freeman and Companyp the Theory of Niche Nic

31、he-functional role an organism plays in its surroundings. In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other. It is mainly point to a populations position of time and space in a natural ecological system, and also the relationsh

32、ip with related populations.34生態(tài)位生態(tài)位(niche)(niche)：物種在生物群落或生態(tài)系統(tǒng)中的地：物種在生物群落或生態(tài)系統(tǒng)中的地位和角色。主要指在自然生態(tài)系統(tǒng)中一個(gè)種群在時(shí)位和角色。主要指在自然生態(tài)系統(tǒng)中一個(gè)種群在時(shí)間、空間上的位子及其與相關(guān)種群之間的功能關(guān)系。間、空間上的位子及其與相關(guān)種群之間的功能關(guān)系。(c) 2001 W.H. Freeman and Company35(c) 2001 W.H. Freeman and Company Fundamental Niche 基基礎(chǔ)礎(chǔ)生生態(tài)態(tài)位位 describes the total range of e

33、nvironmental conditions that are suitable for a species existence without the effects of inter-specific competition and predation from other species. Realized Niche 實(shí)際實(shí)際生生態(tài)態(tài)位位 describes the part of the fundamental niche that a species actually occupies. 36p the Theory of Niche(c) 2001 W.H. Freeman a

34、nd CompanyDifferences among some concepts A. Ecological Niche生生態(tài)態(tài)位位: the status of species using resources. B. Biotope 生活小區(qū)生活小區(qū): the ambientenviroment that a creature lives. C. Ecotope 生生態(tài)態(tài)區(qū)區(qū): The total resources utilized by a species are considered the term ecotope. D. Habitat 棲息地棲息地: Location where a plant or animal lives.37p the Theory of Niche(c) 2001 W.H. Freema