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普通生态学7 种内与种间关系本章内容关系类型种内关系种间关系种内种间关系的基本类型种内关系：生物种群内部的个体间的相互作用种间关系：同一生境中的不同物种间的相互作用种内、种间相互作用的种类●竞争、捕食(自相残杀)、互利共生、寄生相互作用类型互利共生偏利作用捕食/牧食/寄生种间竞争偏害作用中性作用物种A＋＋＋——０物种B＋０——００种内关系密度效应性别关系领域性和社会等级他感作用密度效应在一定时间内，当种群的个体数目增加时，就必定会出现邻接个体之间的相互影响，这种影响与密度有关，称为密度效应植物的密度效应表现为●最后产量衡值法则：单位面积产量不因密度增加而增加●-3/2自疏法则：密度过大时，将有部分个体死亡最后产量衡值法则在一定范围内，当条件相同时，不管一个种群的密度如何，最后产量差不多总是一样的Y 单位面积产量，植物个体平均重量，d 为密度，K i 常数原因：密度增加时，竞争加强，生长率下降，个体变小应用iK d W Y =⨯=W密度效应-3/2自疏法则自疏：同一种生物因生长而导致部分个体死亡的现象自疏导致的个体重量和密度间的关系为植物个体平均重量，d 为密度，C 常数。

两边取对数则双对数曲线斜率为-3/2，称为-3/2自疏法则生物体的重量(体积)增加比密度降低快得多2/3-⨯=d C w w dC w lg 23lg lg -=黑麦草的自疏Regression lines from self-thinning curves for stands of different species of plants31性别生态学内容：性别关系类型、动态及环境因素对性别的影响两性细胞的结合与有性繁殖性比性选择植物的性别系统动物的婚配制度两性细胞的结合与有性繁殖有性繁殖和无性繁殖的优点●无性生殖：迅速占领生境、保证遗传的稳定性●有性生殖：产生不同基因型的后代、适应变化的环境有性繁殖的种类●雌雄同体,同体受精→雌雄同体,异体受精→雌雄异体红皇后效应：病原体-宿主间的生殖进化病原体进攻遗传一致的宿主种群使其淘汰→行有性生殖、不断变化基因型的宿主得以保存→宿主的多型使病原体也行有性生殖产生多型的后代，保持进攻多型宿主的能力性比表示法：雄体:雌体稀少型有利：数量少的性别具有较高的适合度 Fisher氏性比理论：性比趋于1:1两性相等投入：便宜的性别具有更多的个体数生殖成效最大化●存在局域资源竞争时，雄仔离开家区●存在局域交配竞争时，性比偏雌性选择概念：动物行为、大小、形态等次生性征的差异性选择的产生：配偶竞争中生殖成效区别●性内选择：配偶竞争，如打斗武器●性间选择：异性偏爱，如奢侈特征让步赛理论●拥有奢侈特征的个体有好的基础Fisher氏私奔模型●异性喜欢的特征被编码，从而遗传给后代植物的性别系统雌雄同花(两性花)同株异花(单性花)雌雄异株原因－环境因素和进化策略●藤露兜树实例动物的婚配制度婚配制度●群体内婚配制度类型，异性的相互识别，配偶数目，持续时间，对后代的照顾婚配制度的类型●单配制●一雌多雄制●一雄多雌制环境影响●环境的资源质量和分布领域性和社会等级领域性●领域：指由个体、家庭或其他社群单位所占据的，并积极保卫不让同种其他成员侵入的空间●领域行为：鸣叫、气味标志、威胁、直接进攻入侵者的保护领域的行为●领域面积与动物及环境的关系：体重、食物品质、季节社会等级●社会等级现象：动物种群中个体的地位具有一定顺序的现象●社会等级的形成：支配行为●社会等级的意义：优胜劣汰领域性、社会等级和种群调节●种群数量调节●物种进化他感作用他感作用●植物体通过向体外分泌代谢过程中的化学物质，对其他植物产生直接或间接影响的现象●存在于种内和种间克生物质●乙烯、香精油、酚及其衍生物，不饱和内脂、生物碱、配糖体等生态意义●对农林业生产的影响：歇地现象●影响植物群落的种类组成●植物群落演替的重要内在因素种间关系种间关系●指两个或多个不同物种在共同的时间和空间环境中生活，由于不同物种相互成为环境因子，形成了不同物种之间的相互作用主要研究方向●相互动态：相互作用的不同物种的种群动态●协同进化：物种在进化上的相互作用关系类型●种间竞争、捕食作用、寄生和共生种间竞争高斯假说竞争的类型和特征Lotka-Volterra 模型生态位理论竞争释放和性状替换种间竞争与时空异质性概念●两种或多种生物因利用共同资源而产生的使其受到不良影响的相互关系称为种间竞争竞争结果●一方获胜，另一方被抑制或消灭竞争能力●生态习性●生活型●生态幅度高斯假说(竞争排斥原理)在一个稳定的环境内，两个以上受资源限制的、但具有相同资源利用方式的物种，不能长期共存在一起要求相同资源的两个物种不共存与一个空间长期共存在同一地区的两个物种，由于剧烈竞争，他们必然会出现栖息地、食物、活动时间或其他特征上的生态位分化高斯假说Growth curves for Paramecium aurelia and P. caudatumin separate and mixed culturesP . caudatumP . caudatumP . aureliaP . aureliaSeparatelyMixed星杆藻(Asterionella)和针秆藻(Yynedra)Resource partitioningResource partitioning •Resourcepartitioning isdemonstratedby the feedinghabits of fivespecies ofNorthAmericanwarblers.Each of theseinsect-eatingspeciessearches forfood indifferentregions ofspruce trees.竞争的类型和特征种间竞争的类型●利用性竞争：通过损耗资源●干扰性竞争：竞争个体间直接相互作用种间竞争的特征●不对称性●对不同资源竞争的结果相互影响Lotka-Volterra模型假设两个物种，单独生长时增长曲线为逻辑斯蒂模型若将两个物种放在一起，他们发生竞争，从而影响其他种群增长：●假设α表示在物种1的环境中，每存在一个物种2的个体，对于物种1的效应。

电子产品说明书

ElettrologiaCircuiti a corrente continua e alternataCarica e scarica di un condensatoreMISURAZIONE DEI TEMPI DI CARICA E SCARICAUE3050105 09/16 JöS/UDFig. 1: Apparecchio di carica e scarica in funzione con coppia condensatore/resistenza esterna (sinistra) e interna (destra)BASI GENERALIIn un circuito a corrente continua, attraverso un conden-satore passa corrente solo durante l'accensione o lo spe-gnimento. Tramite la corrente, il condensatore viene cari-cato all'accensione, fino al raggiungimento della tensione applicata, e scaricato allo spegnimento, finché la tensione non ha raggiunto lo zero.Per un circuito a corrente continua con capacità C , resistenza R e tensione continua U 0 vale all'accensione(1) 0()(1)t U t U e -τ=⋅- e allo spegnimento(2) 0()t U t U e-τ=⋅con la costante di tempo(3) R C τ=⋅.Per verificare tale correlazione, nell'esperimento vengono mi-surati i tempi necessari al raggiungimento delle tensioni di con-fronto predefinite. Il cronometro viene pertanto avviato con la fase di carica o scarica e successivamente arrestato per mezzo di un comparatore non appena la tensione di confronto risulta raggiunta. La misurazione di diverse tensioni di confronto con-sente di analizzare punto per punto la curva di carica e scarica. Interessante dal punto di vista pratico è anche il tempo(4) 5%ln(5%)3t R C R C =-⋅⋅≈⋅⋅,in cui la tensione del condensatore in fase di scarica raggiungeil 5% del valore di default U0 e in fase di carica raggiunge il 95% del valore finale U0. Tramite la misurazione di t5% è possibile monitorare ad es. i parametri R e C.ELENCO DEGLI STRUMENTI1 Apparecchio di carica e di scarica@230V 1017781 (U10800-230) o1 Apparecchio di carica e di scarica@115V 1017780 (U10800-115) 1 Condensatore 1000 µF, 16 V,P2W191009957 1017806 (U333106)1 Resistenza 10 kΩ, 0,5 W,P2W19 1012922 (U333030) Ulteriormente consigliato:1 Multimetro digitale P1035 1002781 (U11806)MESSA IN FUNZIONE∙Collegare l'apparecchio di carica e scarica alla rete tramite l'alimentatore a spina fornito in dotazione.AVVERTENZE GENERALINelle posizioni INTERN 1, INTERN 2 o INTERN 3 il condensa-tore interno è collegato ai jack di ingresso per la capacità esterna. I condensatori interno ed esterno sono in questo caso collegati in parallelo.∙Per le misurazioni sulle coppie RC interne non collegare capacità esterne.Il tempo di carica e scarica misurato è influenzato da tempi di rimbalzo, amplificati da una mano insicura nel ruotare il com-mutatore di funzione.∙Ruotare il commutatore di funzione in maniera spedita.∙Per una determinazione più precisa del tempo, ripetere ciascuna misurazione almeno tre volte e ricavare il valore medio.∙Scegliere coppie R/C esterne con costante di tempo 4sR C⋅>.ESECUZIONEMisurazione su coppie condensatore/resistenza interne∙Rimuovere resistenze e condensatori esterni.∙Portare il selettore su INTERN 1, INTERN 2 o INTERN 3. Misurazione su coppie condensatore/resistenza esterne ∙Inserire resistenza e condensatore esterni.∙Portare il selettore su EXTERN.Misurazione del tempo di carica t C∙Portare il commutatore di funzione in posizione CHARGE – STOP. ∙Impostare l'interruttore passo-passo sul valore desiderato. ∙Premere brevemente il tasto RESET per azzerare il conta-tore digitale.∙Portare il commutatore di funzione in posizione CHARGE – START per avviare la carica e la misurazione del tempo. ∙Prendere nota del tempo misurato non appena il contatore si arresta.Misurazione del tempo di scarica t DC∙Procedere come per la curva di carica portando tuttavia il commutatore di funzione rispettivamente in posizione DI-SCHARGE – STOP e DISCHARGE – START. Determinazione del tempo t5%Il tempo t5% può essere determinato con una misurazione sia della carica sia della scarica (v. spiegazioni in merito all'equa-zione (4)). Una maggiore precisione è ottenibile mediante la determinazione della media delle due misurazioni:∙Misurare il tempo di carica t C, 5% per 9,5 V.∙Misurare il tempo di scarica t CC, 5% per 0,5 V.∙Calcolare la media (t C, 5% + t CC, 5%) / 2 = t5% .Registrazione della curva di carica∙Regolare l'interruttore passo-passo per tensione di con-fronto su 0,5 V e determinare il tempo di carica come indi-cato in "Misurazione del tempo di carica".∙Per misurare il valore successivo, girare l'interruttore passo-passo avanti di un livello e ripetere tutte le opera-zioni.Registrazione della curva di scarica∙Regolare l'interruttore passo-passo per tensione di con-fronto su 9,5 V e determinare il tempo di scarica come in-dicato in "Misurazione del tempo di scarica".∙Per misurare il valore successivo, girare l'interruttore passo-passo avanti di un livello e ripetere tutte le opera-zioni.Determinazione della capacità esterna/interna e delle resi-stenze interne∙Portare il selettore per coppia R/C in successione su IN-TERN 1, INTERN 2 e INTERN 3 e misurare rispettiva-mente tre volte i tempi t C, 5% e t CC, 5%, come descritto sopra.Riportare i valori nella Tab. 5 e determinare il tempo t5%. ∙Inserire il condensatore esterno. Portare il selettore per coppia R/C ad es. su INTERN 3 e misurare rispettiva-mente tre volte i tempi t C, 5% e t CC, 5%, come descritto sopra.Riportare i valori nella Tab. 5 e determinare il tempo t5%. ∙Inserire inoltre la resistenza esterna. Portare il selettore per coppia R/C su EXTERN e misurare rispettivamente tre volte i tempi t C, 5% e t CC, 5%, come descritto sopra. Riportarei valori nella Tab. 5 e determinare il tempo t5%.ESEMPIO DI MISURAZIONETab. 1: Tempi di carica e scarica della coppia R/C interna 1.Tab. 2:Tempi di carica e scarica della coppia R/C interna 2.Tab. 3: Tempi di carica e scarica della coppia R/C interna 3.Tab. 4:Tempi di carica e scarica della coppia R/C esterna.Tab. 5: T empi di carica e scarica t C,5% e t CC,5% delle tre coppie R/C interne, della coppia R/C interna 3 con collegamento in paral-lelo al condensatore esterno, della coppia R/C esterna e tempi t 5% derivanti dalla determinazione della media.3B Scientific GmbH, Rudorffweg 8, 21031 Amburgo, Germania,ANALISIRegistrazione delle curve di carica e scarica ∙Registrare graficamente le tensioni impostate U C rispetto ai tempi di carica e scarica misurati t C e t CC (Tab. 1 – 4).Le Figg. 2 e 3 mostrano in modo esemplare le curve di carica e scarica relative alla coppia R/C interna 3. L'andamento espo-nenziale previsto in base alle equazioni (1) e (2) risulta confer-mato.Determinazione della capacità esterna/interna e delle resi-stenze interneCon resistenza esterna nota R ext = 10 k Ω (tolleranza 5%), la capacità esterna C ext viene calcolata in base a (4) dal tempo t 5% = t 5%, ext (Tab. 5):(5) 5%,ext ext ext35,4s1180F 3310k t C R ===μ⋅⋅Ω.Tale valore corrisponde, nell'ambito di tolleranza specificato pari a 20%, con il valore nominale 1000 μF.Per i tempi t 5% determinati per la coppia R/C interne 3 con e senza collegamento al condensatore esterno, vale in base all'equazione (4):(6) 5%,3int,3int 3t R C =⋅⋅ e(7) ()5%,3ext int,3int ext 3t R C C =⋅⋅+.Fig. 2: Curva di carica della coppia RC interna 3 La divisione dell'equazione (7) per l'equazione (6) e l'inseri-mento dei tempi da Tab. 5 dà:(8)5%,3int ext 5%,3ext 5%,364,1s1180F 98,5s 64,1s 2199Ft C C t t =⋅=μ⋅--=μ.Tale valore corrisponde, nell'ambito di tolleranza specificato pari a 10%, con il valore nominale 2000 μF.Infine, le tre resistenze interne ancora ignote R int, i si ottengono dai rispettivi tempi di carica e scarica (Tab. 5) e dalla capacità interna determinata in precedenza C int :(9) 5%,int, i int3i t R C =⋅ mit i = 1, 2, 3Ne deriva:(10) int, 114,0s212232199FR ==Ω⋅μ.(11) int, 232,4s491132199FR ==Ω⋅μ.(12) int, 364,1s971732199FR ==Ω⋅μ.I valori coincidono con i valori nominali 2,2 k Ω, 5,1 k Ω e 10 k Ω.Fig. 3: Curva di scarica della coppia RC interna 3U / V t/ sU / V t / s。

Acct Ch12 Environ Cost (May 21)

12 -6
Incentives and causes for increased efficiency:
1) Customers are demanding products that are environmental friendly
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Incentives and causes for increased efficiency:
Environmental Quality Cost Model
Environmental costs are costs that are incurred because poor environmental quality exists or may exist. Environmental costs can be classified in four categories: prevention costs, detection costs, internal failure costs, and external failure costs.
Scenario – Environmental Study (p.364)
G Study on effluent treatment system; dumping
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residues into river, above level permitted by law
G Fish kills, drinking water to a million people G Consider a new project to treat effluent problem;
G Per the World Bank (June 2006), China had 16 of 20 most-

2023年12月英语六级阅读原文

2023年12月英语六级阅读原文原文标题：The Importance of Environmental Protection随着工业化和城市化的进程不断加快，环境问题已经成为全球性的焦点。

关于这一话题，许多人有不同的看法。

有一些人认为环境污染是制约人类社会发展的主要障碍之一，应当尽快加强环境保护。

而也有一些人对此持怀疑和否定态度，认为环境问题并不严重，环境污染对人类社会的发展不构成实质性的威胁，因此不必大惊小怪。

无论如何，我们都不能忽视环境问题的存在和严重性。

环境保护的重要性首先体现在生态系统的稳定和人类生存环境的改善。

生态系统是地球上的重要基础设施，不同的生物之间通过各种复杂的生态关系相互依存，形成生态系统的稳定性。

然而，由于人类活动过度开发和环境污染，使得原有的生态系统遭到破坏，生物多样性下降，一些濒临灭绝的物种濒临灭绝。

这对于人类生存环境产生了严重的影响。

加强环境保护，保持生态系统的稳定性，保护生物多样性是十分必要的。

环境保护对于人们的身体健康和身心健康是至关重要的。

环境污染直接危害人们的身体健康，长期暴露在污染环境中会导致各种慢性疾病的发生，甚至致癌。

而且，环境污染还会对人们的心理健康造成影响，长期生活在污染环境中会使人产生消极的情绪，降低人们的生活质量。

为了保护人们的身体健康和身心健康，必须加强环境保护，减少环境污染。

环境保护与可持续发展的理念相一致，是现代社会发展的必由之路。

可持续发展是指经济、社会和环境的协调发展，即在满足当前需求的前提下，能够保证子孙后代也能满足其需要。

如果环境得不到有效的保护，将严重威胁人类社会的可持续发展，甚至会导致资源过度消耗，生态平衡被打破，给子孙后代留下巨大的环境债务。

加强环境保护，推动可持续发展已成为全球热点问题。

环境保护对于人类社会的发展至关重要。

只有加强环境保护，才能保障生态系统的稳定和人类生存环境的改善，保护人们的身体健康和身心健康，推动可持续发展。

ECO中心ECO作业训练课件

ECO中心ECO作業訓練教材一、目的本教材之目的在于說明ECO系統工具處理的相關操作，為后補人員或新進人員進行ECO系統教育，通過學習使其能在ECO發生時，對工具及WIP 板子進行處理作業。

二、範圍此教材適用于有ECO時，配合ECO系統各作業規範對ECO文件進行處理，舊生產工具及WIP板子的處理。

便于ECO作業人員學習掌握ECO時舊生產工具的處理及ECO時WIP板子的處理作業。

三．說明制前工程課的功能=設計+制具+工具管理。

ECO中心主要進行有ECO時，進行工具的管理及處理作業，從而達到工具的有序流動，及現場生產工具的正確使用。

故ECO處理作業是制前工程課工作的一個重要項目。

ECO 系統對于PCB專業知識要求較高，需具備相關設計知識。

所以應結合ECO 作業規範和設計準則及設計作業規範學習。

此教材主要為操作步驟說明，若與作業規範有抵觸，作業規範優先于此訓練教材，并希望能指正，便于修訂。

第一節概論ECO(ENGINEERING CHANGE ORDER)中心是制前工程課的一個作業單元，主要進行ECO處理。

1制前工程課功能﹕制前工程功能=P.C.B.生產工具之設計+ 制具+ 變更處理2ECO中心職責﹕2-1ECO內容檢核2-2發料控制系統管制2-3ECO時工具及WIP板子處理WIP查詢WIP板子及舊工具處理ECO文件處理ECO FOLLOW-UP多料號ECO管制無訂單ECO管制報廢ECO處理ECO WIP現場流程單更改、更換3ECO中心ECO時涉及處理之PCB生產工具有（指由制前工程課提供之生產工具）3-1流程單3-2工作底片﹕內存底片、外層底片、抗鍍金底片、綠漆曝光底片、印字底片、檔墨底片、塞孔底片、孔位底片3-3鑽孔&切型程式3-4O/S、P/G模具3-5電流條件（電鍍）4 作業常用名詞簡介4-1PCB(PRINT CIRCUIT BOARD):印刷線路板4-2ECO(ENGINEERING CHANGE ORDER):工程更改通知單4-3A/W(ART WORK):底片4-4W/F(WORKING FILM):工作底片4-5SPEC(SPECIFICATION):品質規範4-6PATTERN:板面圖形4-7PTH(PLATE THROUGH HOLE):電鍍孔4-8N-PTH:非電鍍孔4-9P/N(PART NO.):料號4-10SMT(SURFACE MOUNTING TECHNOLOGY):表面粘著技術4-11S/S(SILK SCREEN):印字4-12S/M(SOLDER MASK):綠漆4-13G/F(GOLD FINGER):金手指4-14PAD:焊墊、園墊4-15L/W(LINE WIDTH):線寬4-16L/S(LINE SPACING):線距4-17A/R(ANNULAR RING):孔環4-18GND LAYER:接地層4-19VCC/POWER LAYER:電壓層4-20SIG(SIGNAL) LAYER:線路層4-21COUPON:板邊式樣4-22V-CUT:V型切槽4-23SLOT:橢圓孔（槽）4-24D/F(DRY FILM):干膜4-25LAY-UP:疊板4-26COMP（COMPONET）SIDE:零件面4-27SOLDER SIDE:焊錫面5ECO簽發時機ECO簽發時機為PCB規格、資料需變更或生產工具需要更改時。

昆明2024年统编版小学六年级Y卷英语第4单元期末试卷

昆明2024年统编版小学六年级英语第4单元期末试卷考试时间：100分钟（总分:110）A卷考试人：_________题号一二三四五总分得分一、综合题(共计100题)1、听力题：We bake _____ (饼干) for the party.2、填空题：I enjoy going to the ______ to see animals.3、What is the name of the fairy tale character who lost her glass slipper?A. Snow WhiteB. CinderellaC. Sleeping BeautyD. Rapunzel4、What is the shape of a soccer ball?A. SquareB. TriangleC. CircleD. Rectangle5、听力题：She has a nice ________.6、填空题：My friend enjoys __________ (打篮球).7、填空题：The _______ (The Bolshevik Revolution) brought communism to Russia.8、听力题：The chemical formula for ethylene glycol is _____.The invention of the wheel was significant for _______.10、填空题：The _____ (果实) from trees can be harvested in fall.11、填空题：I like to draw ______ in my spare time.12、填空题：Turtles can hide in their ______ (壳).13、填空题：I saw a _______ (小骆驼) at the zoo yesterday.14、填空题：I made a _________ (玩具博物馆) to display my favorite pieces.15、What is the name of the popular board game where you try to take over the world?A. RiskB. MonopolyC. Settlers of CatanD. Clue答案: A16、填空题：My teacher is _______ (友好的).17、填空题：The ______ (液体) within plant cells is called cytoplasm.18、填空题：The _____ (绿意盎然) of the forest is refreshing.19、What is the name of the famous artist known for his paintings of water lilies?A. PicassoB. MonetC. Van GoghD. Renoir20、填空题：The __________ is a famous river that flows through Germany. (莱茵河)The ________ was a major conflict fought in the 1860s in the United States.22、听力题：The capital of Marshall Islands is _______.23、填空题：I like to draw a picture of a ________.24、听力题：The process of extracting metals from ores is called _____.25、填空题：My mom is a great _______ (厨师).26、填空题：The __________ (历史的影响范围) extends beyond borders.27、What do you call the process of plants making food using sunlight?A. RespirationB. DigestionC. PhotosynthesisD. Evaporation答案: C28、填空题：The first successful heart surgery was performed by _______. (克里斯托弗·里德)29、听力题：The capital of Peru is ________.30、填空题：My sister is very __________ (灵巧).31、填空题：The __________ (三角贸易) involved the exchange of goods and slaves.32、What do you call a place where you can watch plays?A. TheaterB. CinemaC. MuseumD. Concert hall答案:A33、In which month do we celebrate Halloween?A. SeptemberB. OctoberC. NovemberD. December34、填空题：The cat chases _______ (光点) from a laser.35、听力题：Chemical changes can be identified by changes in ________ or color.36、填空题：A garden can bring ______ (快乐) to families.37、填空题：The __________ (拿破仑战争) changed Europe significantly.38、What is the color of a typical mint leaf?A. GreenB. YellowC. BlueD. Red答案:A39、选择题：What do we call the place where you can borrow books?A. LibraryB. BookstoreC. ClassroomD. Office40、听力题：A heterogeneous mixture can be seen with the ______.41、填空题：Herbs are often used in cooking to add ______. (草药常用于烹饪中以增加风味。

Environmental Ecology(生态学第五版)

What Is Ecology?
Forest Nutrient Budgets
• For ecologists who study the budgets of nutrients such as nitrogen, phosphorus, or calcium, one of the first steps is to inventory their distribution within an ecosystem • Nalini Nadkarni---inventories by her changed our ideas of how tropical and temperate rain forests are structured and how they function
Useful Guide of Studying Ecology
Rule 3: Nothing happens for the good of the species
A very common misconception is the idea that patterns of behavior in organisms which appear to be costly to an individual occur for the good of the species. This is absolutely and completely wrong Natural selection will favor those genes which are passed on to the most offspring, even if these genes may cause a reduction in the species‘ population size

Chap曼昆微观经济学-

Chap曼昆微观经济学-Aggregate Demand and Aggregate SupplyChapter 31Short-Run Economic Fluctuations Economic activity fluctuates fromyear to year. Inmost years production of goods and services rises. On average over the past 50 years, production in the U.S. economy has grown by about 3 percent per year. In some years normal growth does not occur, causing a recession.Short-Run Economic Fluctuations Arecession is a period of declining real GDP, falling incomes, and rising unemployment. A depression is a severe recession.Three Key Facts About Economic Fluctuations Economicfluctuations are irregular and unpredictable. Fluctuationsin the economy are often called the business cycle.Mostmacroeconomic variables fluctuate together. As output falls, unemployment rises.A Look At Short-Run Economic Fluctuations(a) Real GDP Billions of 1992 Dollars $7,000 6,500 6,000 5,500 5,000 4,5004,000 3,500 3,000 2,500RecessionsReal GDP1965197019751980198519901995Three Key Facts About Economic Fluctuations Most macroeconomic variablesfluctuate together. Mostmacroeconomic variables that measure some type of income or production fluctuate closely together. Although many macroeconomic variables fluctuate together, they fluctuate by different amounts.A Look At Short-Run Economic Fluctuations(b) Investment Spending Billions of 1992 Dollars $1,100 1,000 900 800 700 600 500 400 300 __RecessionsInvestment spending198519901995Three Key Facts About Economic Fluctuations As output falls, unemployment rises.Changes in real GDP are inversely related to changes in the unemployment rate. During times of recession, unemployment rises substantially.A Look At Short-Run Economic Fluctuations(c) Unemployment Rate Percent of Labor Force 12 10 8Unemployment rateRecessions64 2 0 __ 1985 1990 1995How the Short Run Differs From the Long Run Mosteconomists believe that classical theory describes the world in the long run but not in the short run. Changesin the money supply affect nominal variables but not real variables in the long run. The assumption of monetary neutrality is not appropriate when studying year-toyear changes in the economy.The Basic Model of Economic Fluctuations Two variables are used to develop amodel to analyze the short-run fluctuations. Theeconomy’s output of goods and services measured by realGDP. The overall price level measured by the CPI or the GDP deflator.The Basic Model of Economic FluctuationsEconomist use the model of aggregate demand and aggregate supply to explain short-run fluctuations in economic activity around its long-run trend.The Basic Model of Economic Fluctuations Theaggregate demand curve shows the quantity of goods and services that households, firms, and the government want to buy at each price level.The Basic Model of Economic Fluctuations Theaggregate supply curve shows the quantity of goods and services that firms produce and sell at each price level.Aggregate Demand and Aggregate Supply...Price Level Aggregate supplyEquilibrium price levelAggregate demand 0Equilibrium outputQuantity of OutputThe Aggregate Demand Curve The four components of GDP (Y)contribute to the aggregate demand for goods and services.Y = C + I + G + NXThe Aggregate-Demand Curve...Price LevelP11. A decrease in the price level...P2Aggregate demand 0Y1Y22. 。

Campbell生物学（生物学）12版：Pearson eText 产品说明说明书

ivvBioFlix Animation Mechanics of breathingExpanding the thoracic cavity during inhalation involves theanimal’s rib muscles and the diaphragm , a sheet of skeletal muscle that forms the bottom wall of the cavity. Contracting the ribistudents visualize complex BioInteractive Videos and Animations, new Figure 3-D Animations, Galápagos Rosemary Grant, and more.The Pearson eText app isavailable for download in theapp store for approved devices.viieText and available for assignment in Mastering Biology. viii35. On these diagrams of plant and animal cells, label each organelle and give a brief statement of its function.Concept 6.6 The cytoskeleton is a network of fibers that organizes structures and activities in the cell36. What is the cytoskeleton?37. What are the three roles of the cytoskeleton?38. There are three main types of fibers that make up the cytoskeleton. Name them.39. Microtubules are hollow rods made of a globular protein called tubulin. Each tubulinprotein is a dimer made of two subunits. These are easily assembled and disassembled.What are four functions of microtubules?BLOOD SALT WATER CHLORIDECELLK +K +Na +Na +Cl –Flagellar motorH +Filament of ﬂagellumHookH 2O Stoma H 2OH 2O H 2OK 1H 2OGua rd cellsK 1H 1H 1The transport of ions across the plasma membrane of a cell is a fundamental activity of all animals, and indeed of all living things. By generating ion gradients, ion transport provides the potential energy that powers processes ranging from an organism’s regulation of salts and gases in internal ﬂuids to its perception of and locomotion through its environment.In marine bony ﬁshes, ion gradients drive secretion of salt(NaCl), a process essential to avoid dehydration. Within gills, the pumps,cotransporters, and channels of specialized chloride cells function together to drive salt from the blood across the gill epithelium and into the surrounding salt water. (See Figure 44.3.)Ion gradients provide the basis for the opening of a plant stoma by surrounding guard cells. Active transport of H + out of a guard cell generates a voltage (membrane potential) that drives inward movement of K +. This uptake of K + by guard cells triggers an osmotic inﬂux of water that changes cell shape, bowingthe guard cells outward and thereby opening the stoma. (See Concept 36.4.)In neurons, transmission of information as nerve impulses is made possible by the opening and closing of channels selective for sodium or other ions. These signals enable nervous systems to receive and process input and to direct appropriate output, such as this leap of a frog capturing prey. (See Concept 48.3 and Concept 50.5.)A gradient of H + powers the bacterial ﬂagellum. An electron transport chain generates this gradient, establishing a higher concentration of H + outside the bacterial cell. Protons reentering the cell provide a force that causes the ﬂagellar motor to rotate. The rotating motor turns the curved hook, causing the attached ﬁlament to propel the cell. (See Concept 9.4 and Figure 27.7.)NEURONNa +Na +Channel open Channel closedOsmoregulationInformation ProcessingGas ExchangeLocomotionIon Movement and Gradients . Figure 44.17MAKE CONNECTIONSMastering Biology BioFlix ® Animation: Membrane TransportExplain why the set of forces driving ion movement across the plasma membrane of a cell is described as an electrochemical (electrical and chemical) gradient (see Concept 7.4).MAKE CONNECTIONSCHAPTER 44 Osmoregulation and Excretion 993Make Connections Tutorials connect contentfrom two different chapters using art from the book. Make Connections Tutorials are assignable and automatically graded in Mastering Biology and include answer-specific feedback for students.CONCEPT CHECK 24.21.Summarize key di erences between allopatric and sympatric speciation. Which type of speciation is more common, and why?2.Describe two mechanisms that can decrease gene ﬂow in sympatric populations, thereby making sympatric speciation more likely to occur.3.WHAT IF? Is allopatric speciation more likely to occur on an island close to a mainland or on a more isolated island of the same size? Explain your prediction.4.MAKE CONNECTIONS Review the process of meiosis in Figure 13.8. Describe how an error during meiosis could lead to polyploidy.For suggested answers, see Appendix A.Scientific Skills Exercisesevery chapter of the text use realdata to build key skills needed forbiology, including data analysis,graphing, experimental design, andmath skills. Each exercise is alsoavailable as an automatically gradedassignment in Mastering Biologywith answer-specific feedback forstudents.Problem-SolvingExercises guide students in applying scientific skills and interpreting real data in the context of solving a real-world problem. A version of each Problem-Solving Exercise can also be assigned in Mastering Biology.In this exercise, you will investigate whether amphibians can acquire resistance to thefungal pathogen Bd.Your Approach The principle guiding your investigation is that prior exposureto a pathogen can enable amphibians to acquire immunological resistance to thatpathogen. To see whether this occurs after exposure to Bd, you will analyze data onacquired resistance in Cuban tree frogs (Osteopilus septentrionalis).Your Data To create variation in n u mber of prior exposures to Bd, Cuban tree frogswere exposed to Bd and cleared of their infection (using heat treatments) from zeroto three times; frogs with no prior exposures are referred to as “naive.” Researchersthen exposed frogs to Bd and measured mean abundance of Bd on the frog’s skin,frog survival, and abundance of lymphocytes (a type of white blood cell involved inthe vertebrate immune response).I nstructors: A version of this Problem-SolvingExercise can be assigned in Mastering Biology.PROBLEM-SOLVING EXERCISEC an d ec lin in g am ph ib ia npo pu la tio ns b e sa ve d bya va cc in e?Am ph ibi an po pu lat ion s are de cli nin g r ap idl ywo rld wi de. T he fu ng us Batra ch oc hy tri umde nd rob ati dis (Bd) h as cont rib ut ed to th isde cli ne: T his pa th og en caus es sev ere sk ininf ec tio ns in m an y a mp hibian sp ec ies, le ad ingto m ass ive di e-o s. E o rtsto sa ve am ph ibi an sfro m Bd ha ve ha d l im ited s uc ce ss, an dth ere is litt le ev ide nc e t hat f ro gs an d o th eram ph ibi an s h av e a cq uired re sis tan ce to Bd onth eir ow n.Ye llo w-leg ge d f rog s (Rana m us co sa) inCa lifo rn ia kil led by Bd infec tio n24,00012,00016,00014,00018,00020,00022,00001234Bdabundanceonfrog’sskin(organisms/goffrog)Number of priorBd exposures807010302040506001234PercentagesurvivalNumber of prior BdexposuresNumberof priorBdexposuresThousands oflymphocytesper g of frog0134124022443227Your Analysis1. Describe and interpret the results shown in the ﬁgure.2.(a) Graph the data in the table. (b) Based on these data, develop a hypothesisthat explains the results discussed in question 1.3. Breeding populations of amphibian species threatened by Bd have been estab-lished in captivity. In addition, evidence suggests that Cuban tree frogs canacquire resistance after exposure to dead Bd. Based on this information andyour answers to questions 1 and 2, suggest a strategy for repopulating regionsdecimated by Bd.xiiAvailable on smartphones, tablets, and computers.Incorrect; Try AgainYou labeled 2 of 7 targets incorrectly. You have labeled target (a) incorrectly. Notice that this organellehas a smooth membrane. It is involved in building macromolecules, but not proteins.Incorrect; Try AgainYou labeled 2 of 7 targets incorrectly. You have labeled target (a) incorrectly. Notice that this organelle has a smooth membrane. It is involved in building macromolecules, but not proteins.Wrong-Answer Feedback Using data gatheredfrom all of the students using the program, MasteringBiology offers wrong-answer feedback that isspecific to each student. Rather than simply providingfeedback of the “right/wrong/try again” variety,Mastering Biology guides students toward the correctfinal answer without giving the answer away.UPDATED! Test Bank questions have been analyzed and revised with student success in mind. Revisions account for how students read, analyze, and engage with the content.“I wouldn’t have passed my classwithout Mastering Biology. Thefeedback doesn’t just tell me I’mwrong, it gave me a paragraph of feedback on why I was wrong andhow I could better understand it.”—Student, University of Texas at ArlingtonxiiiReady-to-Go Teaching Modules Campbell Biology, Twelfth EditionReady-to-Go Teaching Modules provide instructors with easy-to-use teaching tools for the toughest topics in General Biology.Assign ready-madeactivities andassignments forbefore, during,and after class.Incorporate activelearning withclass-testedresources frombiology instructors.Take full advantage ofMastering Biology andLearning Catalytics,the powerful “bringyour own device”student assessmentsystem.The LightReactionsCONCEPT 10.3MeiosisCONCEPT 13.3MitosisCONCEPT 12.2OxidativePhosphorylationCONCEPT 9.4Mechanisms ofEvolutionCONCEPT 23.3 NEW!DNAReplicationCONCEPT 16.2The trp and lacOperonsCONCEPT 18.1NEW!PhylogeneticTreesCONCEPT 26.3Resting andAction PotentialsCONCEPT 48.3Transport inPlantsCONCEPT 36.2The HumanDigestive SystemCONCEPT 41.3NEW!Cardiac Cycle andHeart FunctionCONCEPT 42.2NEW!TrophicRelationshipsCONCEPT 55.3Interpreting Dataon IntroducedSpeciesCONCEPT 56.1NEW!Gene Expression:MutationsCONCEPT 17.5Early Alerts Mastering Biology help instructors know when students maybe struggling in the course. This insight enables instructors to provide personalized communication and support at the moment students need it so they can stay—and succeed—in the course.。

OG12阅读中文翻译

OG12阅读中文翻译&逻辑简图这是第一篇的，也就是P358的【】内涉及为题号，黄色为考点，红色的不太确定意思的。

E（一种可以通过减少生产过程使环境冲击最小化的方法）成为全球公司的目标，很多公司意识到这样的创新可以节省开支。

PS和GC看到这种发展是值得称赞的，但是认为简单地使用E发明可能会实际上在未来给环境施压更大的压力。

这样的创新减少了生产中的浪费但是并没有改变制造出的产品数量或者那些产品在使用和丢弃过程中造成的浪费。

【3】实际上，大部分公司研发E只是为了增加利润和增长。

此外，并不能保证由于E增加的经济增长会用在其他E的途径上。

【2】因为在现在全球市场上，更多的利润可能会成为再投资老形式不E 产业的资本。

即使一个广泛使用E产业的系统可能，当它变大时，比一个小却不那么E的系统产生更多浪费和破坏更多环境和物种。

S和C主张为了保护全球环境和维持经济增长，企业必须发展一个新的可以减少材料使用量和降低浪费的方法。

专门地注意提供一个按照既定思路又引人注目的业务案例的E，可能会将公司从追求不同产品和商业模式中拉开。

所谓的逻辑简图：E is a goal …PS &GC +, but …, indeed …, moreover …, Even … (eg.),SC: to …, businesses must …PS，那红色部分几乎是用灵格斯译的，原文是which offers a compelling business case according to established thinkingP360最近的一项调查提供了P时代末期食肉动物捕食的力量。

研究者比较了现在食肉动物和36，000至10，000年前食肉动物的齿痕，那些被保存在LA的RLB坑。

已经灭绝的物种造成的齿痕破裂程度比现在物种造成的要显著。

考虑这个发现的可能解释，研究者排除了统计偏差【7】因为在化石样本中老的个体并没有特别显著。

关中平原城市群土地利用变化对碳储量时空格局的影响

中国生态农业学报(中英文) 2024年4月第 32 卷第 4 期Chinese Journal of Eco-Agriculture, Apr. 2024, 32(4): 592−604DOI: 10.12357/cjea.20230508温芮, 高燕燕, 吴志豪, 钱会. 关中平原城市群土地利用变化对碳储量时空格局的影响[J]. 中国生态农业学报 (中英文), 2024, 32(4): 592−604WEN R, GAO Y Y, WU Z H, QIAN H. Effects of land use change on the temporal and spatial pattern of carbon storage in Guan-zhong Plain urban agglomeration[J]. Chinese Journal of Eco-Agriculture, 2024, 32(4): 592−604关中平原城市群土地利用变化对碳储量时空格局的影响*温　芮, 高燕燕, 吴志豪, 钱　会**(长安大学水利与环境学院/旱区地下水文与生态效应教育部重点实验室/水利部旱区生态水文与水安全重点实验室　西安　710064)摘　要: 生态系统碳储量的变化与土地利用的格局关系紧密, 研究碳储量的变化对实现“双碳”目标具有重要意义。

关中平原城市群是西部地区第二大城市群, 国家战略的实施影响着土地利用类型, 进而影响碳储量的时空分布。

本文通过集成InVEST模型与PLUS模型, 解析2000—2020年关中平原城市群土地利用类型和碳储量的时空演化特征, 预测在自然增长、生态保护和经济发展3种情景下, 2030年关中平原城市群土地利用和碳储量的变化。

结果表明: 1) 2000—2020年关中平原城市群主要土地利用类型为耕地和林地, 草地向耕地和林地转换以及耕地向建设用地转换是研究区土地利用类型转换的主要方式。

Eco Ch11 Spr12

11
Competition
11 Competition
• Case Study: Competition in Plants that Eat Animals • Competition for Resources • General Features of Competition • Competitive Exclusion • Altering the Outcome of Competition • Case Study Revisited • Connections in Nature: The Paradox of Diversity
Organisms compete for limited resources
Features of environment required for growth, survival, or reproduction, and… Which can be consumed to point of depletion Basic concept of natural selection
Sarracenia psittacina, the parrot pitcher-plant, found in Florida
/carnivorous_plants/images/Sarracenia_psittacina-SC-2.jpg
Case Study: Competition in Plants that Eat Animals
Galium pumilum
http://www2.lubw.baden-wuerttemberg.de/public/abt2/dokablage/oac_168/typ_01/0102221_5.jpg

12_Eco_Active_CHI

关键信息保护濒危的文化和生态系统并与之建立长期关系成为了重中之重极限运动和跨文化运动成为了巴西奥运年的关注焦点朴实、带有纹理以及层叠的材料混搭成为基本的设计手法——从原始到精致，从人工到天然，各种风格不一而足更具自然和人文关怀的制造过程以全新的方式表达了对生态和人类的尊重以充满创意的全新方式将新的材料与现有材质相结合，显示了人类对资源匮乏问题的重视土地改造消逝之前（Before They Pass）ooho!超级现象 (hyPeroBjecTs）嘎勒语消失的人类基因（LosT human GeneTic archive）在迪拜“未来政府服务博物馆”展出的这件装置作品是利用一个交互式沙坑创作而成，它可以创造或改造出新的地形，并探索它对气候的影响。

由摄影师Jimmy Nelson发起的这项活动旨在从人种史的角度记录部落文化。

该项目记录了那些行将消逝的悠久部落传统和仪式。

Ooho!是一种能淘汰瓶装水塑料瓶的可持续解决方案，它的表层是可食用海藻。

其灵感源自“球化”工艺，可以在家中利用简单食材进行再造。

哲学家Timothy Morton曾使用“超级现象”（hyperobjects）一词来描述对世界影响巨大的事物。

它们难以根据传统的分类法加以归类，全球变暖便是一个具有预见色彩的实例。

美国嘎勒人为非洲黑奴后裔，生活在南卡罗来纳州和佐治亚州。

他们拥有丰富的文化遗产，这一点从他们使用的克里奥尔语就可见一斑。

这种语言是非洲语言与英语的混合体。

这一系列展览的最新一期在巴黎的东京宫上演，日本艺术家Hiroshi Sugimoto创造出了一个后人类的未来世界，我们可以通过它回顾人类这一物种的历史。

生长的电池消绿化设计(The Green machine)自然化石钟（Da naTurafossiLium cLock0反乌托邦野兽派外套（DysToPian BruTaLisT ouTerwear)花园大桥（The GarDen BriDGe)融化的阿雷格里港(meLTinG PorTe aLeGre）生物工程师Angela Belcher的工作重点是控制病毒，使其为人类服务，从而创造出能为“清洁”电池、燃料和太阳能电池提供基础的纳米结构。

Eco板碳源(中英文对照)

G3
a-Ketobutyric Acid
a-丁酮酸
G4
Phenylethyl-amine
苯乙基胺
H1
a-D-Lactose
a-D-乳糖
H2
D,L-a-Glycerol
D,L-a-甘油
H3
D-Malic Acid
D-苹果酸
H4
Putrescine
腐胺
H1
a-D-Lactose
a-D-乳糖
H2
D,L-a-Glycerol
C4
L-Phenylalanine
L-苯基丙氨酸
D1
Tween 80
吐温80
D2
D-Mannitol
D-甘露醇
D3
4-Hydroxy Benzoic Acid 4-羟基苯甲酸
D4
L-Serine
L-丝氨酸
D1
Tween 80
吐温80
D2
D-Mannitol
D-甘露醇
D3
4-Hydroxy Benzoic Acid 4-羟基苯甲酸
D-半乳糖内酯
A4
L-Arginine
L-精氨酸
A1
Water
水
A2
ß-Methyl-D-Glucoside
ß-甲基D-葡萄糖苷
A3
D-Galactonic Acid y-Lactone
D-半乳糖内酯
A4
L-Arginine
L-精氨酸
B1
Pyruvic Acid Methyl Ester
丙酮酸甲脂
B2
B1
Pyruvic Acid Methyl Ester
丙酮酸甲脂
B2

经典创意共赢未来清新绿色环保节能宣传PPT模板课件

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ecological processes稿件模板 -回复

ecological processes稿件模板-回复标题：生态过程的意义及影响：解析生态系统中的关键环节摘要：生态过程是生态系统中各种生物和非生物因素相互作用所导致的一系列复杂事件。

本文将重点介绍生态过程的意义及其对生态系统的影响，并对其中几个关键环节进行详细探讨。

引言：生态过程是指在一个生态系统内，各种生物和非生物因素通过相互作用而产生的一系列复杂事件。

这些过程使得生态系统能够自我维持，并促进物种多样性和生物丰富度的发展。

生态过程的理解对于我们对生态系统的保护和管理具有重要意义。

在本文中，我们将分析生态过程的意义，并对其中几个关键环节进行详细探讨。

一、生态过程的意义1. 促进物质循环：生态过程中的生物相互作用和物质的流动，使得生态系统能够实现元素的循环利用。

例如，生物的呼吸作用导致了氧气的供应和二氧化碳的排放，而植物的光合作用则能够将二氧化碳转化为氧气。

这种物质循环有助于维持生态系统内的平衡，促进养分的再利用。

2. 维持生态平衡：生态过程中的各种相互作用，如食物链和捕食关系，保持了生态系统中不同物种的平衡。

通过控制掠食者和被捕食者的数量，生态过程有助于防止某个物种过度繁殖或灭绝，维持生态系统的稳定性。

3. 保护地球生命：生态过程提供了地球上所有生命的基本需求，如食物、水源和栖息地。

通过保持生态过程的正常运转，我们可以确保地球生命得到支持和保护。

例如，森林生态系统中的蒸腾过程可以维持水循环和降雨模式，为植物和动物提供水源。

二、关键生态过程及其影响1. 光合作用：光合作用是生命能源的主要来源之一，通过将太阳能转化为化学能，植物能够合成有机物质并释放氧气。

光合作用不仅支持了植物的生长和发育，还为其他生物提供了食物和氧气。

此外，光合作用还能够逐渐减少大气中的二氧化碳含量，对缓解气候变化起到积极作用。

2. 分解作用：分解作用是将有机物质分解为无机物质的过程。

这是非常重要的，因为它能够释放出养分，如氮、磷和钾，使得它们重新进入生态系统中。

Economic Cycle

Economic CycleDEFINITION of 'Economic Cycle'The natural fluctuation of the economy between periods of expansion (growth) and contraction (recession). Factors such as gross domestic product (GDP), interest rates, levels of employment and consumer spending can help to determine the current stage of the economic cycle.INVESTOPEDIA EXPLAINS 'Economic Cycle'An economy is deemed to be in the expansion stage of the economic cycle when gross domestic product (GDP) is rapidly increasing. During times of expansion, investors seek to purchase companies in technology, capital goods and basic energy. During times of contraction, investors will look to purchase companies such as utilities, financials and healthcare.IntroductionBritain has just suffered one of the deepest slumps in her post-1945 history; the Euro Area economies have struggled to climb out of recession amid unprecedented levels of financial turbulence and the crippling effects of high private and public sector debtsMany of the world‟s richest coun tries have witnessed damaging contractions in activity since 2008. Few nations have escaped –although countries such as Australia, Poland, Norway and Canada seem to have emerged from the global financial crisis (GFC) in relatively good shape.There are major doubts about the likely pace of growth for advanced nations. The new normal growth rate may be lower than in the last twenty years with important consequences for living standards and the ability of sovereign governments to extract them from the debt crisis.We have had three recessions in the UK since the early 1980s, the most recent started in the spring of 2008 and real GDP fell by more than 4.5% in 2009 and - from peak to trough – the recession led to a 6% fall in national output.In contrast, between 1993 and 2008 Britain enjoyed a period of sustained growth combined with low inflation and falling unemployment –an era oncedubbed by the Governor of the Bank of England, Mervyn King as the …NICE‟ decade, NICE standing for …non-inflationary continuous expansion‟. This came to an abrupt halt in 2007 when global inflationary pressures soared and the world economy was shocked by the sub-prime crisis and the ensuing credit crunch and downturn.What causes the economic cycle?For A2 it is important to grasp the dynamic causes of different stages of the cycle. And to understand how macro developments in one country/region impact on other economies through trade, capital and other resource flows. When looking at the causes of cyclical changes in production, incomes and jobs there are two main approaches:∙Endogenous models explain cyclical fluctuations in terms of internal events or policies i.e. changes which lie within the economic system ∙Exogenous models argue that turning points in an economic cycle happen because of external demand-side or supply-side …shocks‟ from beyond the economic system. These shocks create a disequilibrium for an economy and lead output and prices to deviate from a forecast path Endogenous ModelsThe Stock Cycle∙When demand is strong and running ahead of supply, stocks fall and this is a signal either to raise prices and/or to expand production. Re-stocking can be a way out of a recession.∙Consider the car-scrappage scheme in the UK which was introduced as a way of boosting demand for new vehicles during the recession. This £2,000 cash incentive lead to a spike in demand some of which was met by selling vehicles stuck in vast car parks adjacent to the assembly plants.∙Some of the extra spending on new vehicles will have necessitated a rise in demand for components used in making a new car –there was a positive impact on supply-chain businesses and a rise in demand for stocks leading to an injection of extra incomes in the vehicle industry.In the early stages of a recession, any slump in consumer demand will cause businesses to cut back on output so as to reduce the volume of stocks. We saw this effect at work in 2008-09 as the UK recession became a reality – consider the evidence from the chart below.The chart shows “de-stocking”, in the 1st quarter of 2009, the reduction in the value of stocks amounted to more than £5bn. As British-based carmakers produced fewer cars and house-builders cut back on the number of new homes being built, so the derived demand for cement, bricks, glass, steel, rubber and other raw materials and component parts suffered.Key point: Changes in the stock cycle have important multiplier effects on supply-chain industries. The use of …just-in-time‟ (JIT) stock delivery systems in manufacturing has reduced the need for businesses to hold high stocks of intermediate products. It is now easier for supply to match changes in demand. For example, stocks tend to be less important in the service sector, which now accounts for more than 75 per cent of UK national output.2. Fluctuations in one or more components of aggregate demand (AD)Movements in real GDP in the short term are mainly due to changes in the components of AD and shifts in short-run aggregate supply (SRAS).As with most of the advanced economies, UK household consumption is the largest element accounting for over 65% of spending on goods and services.Here is a way of breaking down the aggregate demand calculation:1.Domestic demand = C + I + G2.External demand = X-M (also known as net trade)3.GDP (Aggregate demand) = C+I+G+X-MFor some countries domestic demand is a high % of total spending (e.g. the USA). In contrast in China, the economy has been driven forward by high trade and current account surpluses and domestic spending has been lower – the Chinese government wishes to boost consumer spending and rely less on exports in order to sustain here fast rate of economic growth in the years ahead. Recap on the main Stages of the CycleBoomA boom happens when real GDP grows faster than the trend growth rate over a number of years. In a boom phase, AD is high and businesses expand output and employment and may also raise profit margins by increasing prices - causing cost-push and demand-pull inflation. The main characteristics of a boom are:∙ A tightening of the labour market: Measured by the rate of unemployment or the number of unfilled job vacancies.∙High demand for imports: Demand increases due to a high marginal propensity to import.∙Public finances: An expansion provides a “fiscal dividend” to the government because tax revenues will be rising as people are earning and spending more. Business profits will be increasing and state spending on welfare tends to fall. A boom can lead to a …fiscal drag‟effect with tax revenues rising more quickly than the economy is growing.∙Strong company profits and investment: An upturn leads to higher profits & investment – this is known as the accelerator effect and you will have covered this at AS level.∙Cyclical boost to productivity: An expanding economy is good news for productivity because businesses are using labour resources more intensively. Productivity growth tends to be pro-cyclical.∙ A risk of higher inflation: Demand-pull and cost-push inflation can occur if AD exceeds potential GDP over time leading an economy to operate with a positive output gap.SlowdownA slowdown occurs when real GDP expands but at a reduced pace – e.g. the UK economy in 2008Recession∙The standard definition of a recession is …two consecutive quarters of negative GDP growth‟ but a more inclusive definition is “a significant decline in activity spread across the economy, lasting more than a few months, normally visible in production, employment, real income, and other indicators.”∙ A depression is a persistent downturn in output and jobs with an economy operating well below its productive potential and where there can be powerful deflationary forces at work. As a rule of thumb, a depression occurs when there is a fall in real GDP of more than 10 per cent from the peak of the cycle to the trough.Symptoms of a recessionThere are many symptoms of a recession – here is a selection of key indicators:1. A fall in purchases of components and raw materials from supply-chainbusinesses2.Rising unemployment and fewer job vacancies for those looking for work3. A rise in the number of business failures4. A contraction in consumer spending & a rise in the percentage of incomesaved (savings ratio)5.Falling private sector capital spending due to weak demand, deterioratinganimal spirits, low profits and rising spare capacity6. A drop in the value of exports and imports of goods and servicesespecially for countries with many industries exposed to changing demand in the world economy7.Price discounts offered by businesses and de-stocking as businesses lookto cut unsold stocksernment tax revenues fall and the budget (fiscal) deficit andgovernment debt grows quicklyThe UK recession of 2008-10 was a result of a mix of internal and external factors– among them:∙The end of the property boom – falling house prices hit wealth and led toa large contraction in new house building, many thousands of jobs werelost in the construction industry∙Reductions in real disposable incomes due to wages rising less quickly than prices∙The lagged effects of rising interest rates in 2007-08 (a tightening of monetary policy caused by rising food and energy prices and inflation above target)∙ A sharp fall in consumer confidence –made worse by the rise in unemployment∙External events– such as recession in trading partners including the USA (which accounts for 15% of UK trade) and the Euro Area (55% of UK trade).Falling exports hit manufacturing industry hard∙Cut-backs in production led to a negative multiplier effect causing a decline in sales and profits for supply-chain businesses. This has contributed to rising unemployment.∙The credit crunch caused the supply of credit to dry up affecting many businesses and home-owners. And falling profits and weaker demand has caused a fall in capital investment –known as the negative accelerator effect. There are few signs of a large recovery in bank lending especially to small and medium sized enterprises (SMEs)The Output GapHow much spare capacity does an economy have to meet a rise in demand? How close is an economy to operating at its productive potential? Has the recessionhad a permanent effect on our ability to supply goods and services? These sorts of questions link to an important concept – the output gap.The output gap is the difference between the actual level of national output and its potential level and is usually expressed as a percentage of the level of potential output.Negative output gap – downward pressure on inflationThe actual level of real GDP is given by the intersection of AD & SRAS – the short run equilibrium. If actual GDP is less than potential GDP there is a negative output gap. Factor resources such as labour and capital machinery are under-utilised and the main problem is higher than average unemployment. More people out of work indicate an excess supply of labour, which means there is downward pressure on real wages. In the next time period, a fall in real wage rates shifts SRAS downwards until actual and potential GDP are identical –assuming labour markets are flexible.Positive output gap – upward pressure on inflationIf actual GDP is greater than potential GDP then there is a positive output gap. Some resources including labour are likely to be working beyond their normal capacity e.g. making extra use of shift work and overtime. The main problem is likely to be an acceleration of demand-pull and cost-push inflation. Shortages of labour put upward pressure on wage rates, and in the next time period, a rise in wage rates shifts SRAS upwards until actual and potential GDP are identical –assuming labour markets are flexible.Recession and the output gap∙The UK will operate with a large negative output gap for some time. But much depends on whether the recession will do long-term damage to our productive capacity.∙This might arise from a rise in business failures and people leaving the labour market if they suffer long periods out of work (long term structural unemployment). This is known as a hysteresis effectWhen a business is operating at less than 100% capacity, it is said to have “spare capacity”.Demand factors:∙Lower demand due to a decline in consumption or demand for raw materials∙Loss of market share due to poor marketing or competitors introducing better products∙Seasonal variations in demand - i.e. temporary spare capacity during off-peak timesSupply factors:∙Increase in capacity not yet matched by increased demand∙Because new technology has been introduced in anticipation of higher demand∙Improvements in productivity mean capacity increases for a given level of demandSpare capacity allows businesses to respond to an unexpected increase in demand, when there is productive slack, i.e. supply is price elastic. It also provides time for maintenance, repairs and employee training.But it can also lead to inefficiency, which makes a business less competitive - and operating below capacity means higher unit costs because fixed costs are being spread over a reduced volume of output. This implies lower profitability than could be achieved.dxThe term business cycle(or economic cycle or boom–bust cycle) refers to fluctuations in aggregate production, trade and activity over several months or years in a market economy.The business cycle is the upward and downward movements of levels of gross domestic product (GDP) and refers to the period of expansions and contractions in the level of economic activities (business fluctuations) around its long-term growth trend. These fluctuations occur around a long-term growth trend, and typically involve shifts over time between periods of relatively rapid economic growth (an expansion or boom), and periods of relative stagnation or decline (a contraction or recession).Business cycles are usually measured by considering the growth rate of real gross domestic product. Despite being termed cycles, these fluctuations in economic activity can prove unpredictable.History[The first systematic exposition of periodic economic crises, in opposition to the existing theory of economic equilibrium, was the 1819 Nouveaux Principes d'économie politique by Jean Charles Léonard de Sismondi. Prior to that point classical economics had either denied the existence of business cycles, blamed them on external factors, notably war, or only studied the long term. Sismondi foundvindication in the Panic of 1825, which was the first unarguably international economic crisis, occurring in peacetime.Sismondi and his contemporary Robert Owen, who expressed similar but less systematic thoughts in 1817 Report to the Committee of the Association for the Relief of the Manufacturing Poor, both identified the cause of economic cycles as overproduction and underconsumption, caused in particular by wealth inequality. They advocated government intervention and socialism, respectively, as the solution. This work did not generate interest among classical economists, though underconsumption theory developed as a heterodox branch in economics until being systematized in Keynesian economics in the 1930s.Sismondi's theory of periodic crises was developed into a theory of alternating cycles by Charles Dunoyer, and similar theories, showing signs of influence by Sismondi, were developed by Johann Karl Rodbertus. Periodic crises in capitalism formed the basis of the theory of Karl Marx, who further claimed that these crises were increasing in severity and, on the basis of which, he predicted a communist revolution. He devoted hundreds of pages of Das Kapital (1867) to crises. In Progress and Poverty (1879), Henry George focused on land's role in crises – particularly land speculation – and proposed a single tax on land as a solution.Classification by periods] In 1860 French economist Clement Juglar first identified economic cycles 7 to 11 years long, although he cautiously did not claim any rigid regularity. Later, economist Joseph Schumpeter (1883–1950) argued that a Juglar Cycle has four stages: 1. expansion (increase in production and prices, lowinterest-rates)2. crisis (stock exchanges crash and multiple bankruptcies of firms occur)3. recession (drops in prices and in output, high interest-rates)4. recovery (stocks recover because of the fall in prices and incomes)Schumpeter's Juglar model associates recovery and prosperity with increases in productivity, consumer confidence, aggregate demand, and prices.In the mid-20th century, Schumpeter and others proposed a typology of business cycles according to their periodicity, so that a number of particular cycles were named after their discoverers or proposers:∙the Kitchin inventory cycle of 3 to 5 years (after Joseph Kitchin); ∙the Juglar fixed-investment cycle of 7 to 11 years (often identified [by whom?] as "the" business cycle) ∙the Kuznets infrastructural investment cycle of 15 to 25 years (after Simon Kuznets – also called "building cycle") ∙ the Kondratiev wave or long technological cycle of 45 to 60 years (after the Soviet economist Nikolai Kondratiev). Proposed Economic Waves Cycle/Wave Name Period Kitchin inventory 3–5 Juglar fixed investment 7–11 Kuznets infrastructural investment 15–25 Kondratiev wave 45–60 Pork cycleInterest in the different typologies of cycles has waned since the development of modern macroeconomics, which gives little support to the idea of regular periodic cycles.OccurrenceA simplified Kondratiev wave, with the theory that productivity enhancing innovations drive waves of economic growth.There were frequent crises in Europe and America in the 19th and first half of the 20th century, specifically the period 1815–1939. This period started from the end of the Napoleonic wars in 1815, which was immediately followed by the Post-Napoleonic depression in the United Kingdom (1815–30), and culminated in the Great Depression of 1929–39, which led into World War II. See Financial crisis: 19th century for listing and details. The first of these crises not associated with a war was the Panic of 1825.Business cycles in OECD countries after World War II were generally more restrained than the earlier business cycles. This was particularly true during the Golden Age of Capitalism (1945/50–1970s), and the period 1945–2008 did not experience a global downturn until the Late-2000s recession. Economic stabilization policy using fiscal policy and monetary policy appeared to have dampened the worst excesses of business cycles, and automatic stabilization due to the aspects of the government's budget also helped mitigate the cycle even without conscious action by policy-makers.In this period, the economic cycle – at least the problem of depressions – was twice declared dead. The first declaration was in the late 1960s, when the Phillips curve was seen as being able to steer the economy. However, this was followed by stagflation in the 1970s, which discredited the theory. The second declaration was in the early 2000s, following the stability and growth in the 1980s and 1990s in what came to be known as The Great Moderation. Notably, in 2003, Robert Lucas, in his presidential address to the American Economic Association, declared that the "central problem of depression-prevention [has] been solved, for all practical purposes. Unfortunately, this was followed by the 2008–2012 global recession.Various regions have experienced prolonged depressions, most dramatically the economic crisis in former Eastern Bloc countries following the end of the Soviet Union in 1991. For several of these countries the period 1989–2010 has been an ongoing depression, with real income still lower than in 1989. This has beenattributed not to a cyclical pattern, but to a mismanaged transition from command economies to market economies.IdentifyingEconomic activity in the US, 1954–2005.Deviations from the long term US growth trend, 1954–2005.In 1946, economists Arthur F. Burns and Wesley C. Mitchell provided the now standard definition of business cycles in their book Measuring Business Cycles: Business cycles are a type of fluctuation found in the aggregate economic activity of nations that organize their work mainly in business enterprises: a cycle consists of expansions occurring at about the same time in many economic activities, followed by similarly general recessions, contractions, and revivals which merge into theexpansion phase of the next cycle; in duration, business cycles vary from more than one year to ten or twelve years; they are not divisible into shorter cycles of similar characteristics with amplitudes approximating their own.According to A. F. Burns]Business cycles are not merely fluctuations in aggregate economic activity. The critical feature that distinguishes them from the commercial convulsions of earlier centuries or from the seasonal and other short term variations of our own age is that the fluctuations are widely diffused over the economy – its industry, its commercial dealings, and its tangles of finance. The economy of the western world is a system of closely interrelated parts. He who would understand business cycles must master the workings of an economic system organized largely in a network of free enterprises searching for profit. The problem of how business cycles come about is therefore inseparable from the problem of how a capitalist economy functions.In the United States, it is generally accepted that the National Bureau of Economic Research (NBER) is the final arbiter of the dates of the peaks and troughs of the business cycle. An expansion is the period from a trough to a peak, and a recession as the period from a peak to a trough. The NBER identifies a recession as "a significant decline in economic activity spread across the economy, lasting more than a few months, normally visible in real GDP, real income, employment, industrial production".ExplanationsThe explanation of fluctuations in aggregate economic activity is one of the primary concerns of macroeconomics. The main framework for explaining such fluctuations is Keynesian economics. In the Keynesian view, business cycles reflect the possibility that the economy may reach short-run equilibrium at levels below or above full employment. If the economy is operating with less than full employment, i.e., with high unemployment, Keynesian theory states that monetary policy and fiscal policy can have a positive role to play in smoothing the fluctuations of the business cycle. There are a number of alternative heterodox economic theories of business cycles, largely associated with particular schools or theorists. There are also some divisions and alternative theories within mainstream economics, notably real business cycle theory and credit-based explanations such as debt deflation and the financial instability hypothesis.Exogenous vs. endogenousWithin mainstream economics, the debate over external (exogenous) versus internal (endogenous) being the causes of the economic cycles, with the classical school (now neo-classical) arguing for exogenous causes and the underconsumptionist (now Keynesian) school arguing for endogenous causes. These may also broadly be classed as "supply-side" and "demand-side" explanations: supply-side explanations may be styled, following Say's law, as arguing that "supply creates its own demand", while demand-side explanations argue that effective demand may fall short of supply, yielding a recession or depression.This debate has important policy consequences: proponents of exogenous causes of crises such as neoclassicals largely argue for minimal government policy or regulation (laissez faire), as absent these external shocks, the market functions, while proponents of endogenous causes of crises such as Keynesians largely argue for larger government policy and regulation, as absent regulation, the market will move from crisis to crisis. This division is not absolute – some classicals (including Say) argued for government policy to mitigate the damage of economic cycles, despite believing in external causes, while Austrian School economists argue against government involvement as only worsening crises, despite believing in internal causes.The view of the economic cycle as caused exogenously dates to Say's law, and much debate on endogeneity or exogeneity of causes of the economic cycle is framed in terms of refuting or supporting Say's law; this is also referred to as the "general glut" debate.Until the Keynesian revolution in mainstream economics in the wake of the Great Depression, classical and neoclassical explanations (exogenous causes) were the mainstream explanation of economic cycles; following the Keynesian revolution, neoclassical macroeconomics was largely rejected. There has been some resurgence of neoclassical approaches in the form of real business cycle (RBC) theory. The debate between Keynesians and neo-classical advocates was reawakened following the recession of 2007.Mainstream economists working in the neoclassical tradition, as opposed to the Keynesian tradition, have usually viewed the departures of the harmonic working of the market economy as due to exogenous influences, such as the State or its regulations, labor unions, business monopolies, or shocks due to technology or natural causes.Contrarily, in the heterodox tradition of Jean Charles Léonard de Sismondi, Clement Juglar, and Marx the recurrent upturns and downturns of the market system are an endogenous characteristic of itThe 19th century school of Underconsumptionism also posited endogenous causes for the business cycle, notably the paradox of thrift, and today this previously heterodox school has entered the mainstream in the form of Keynesian economics via the Keynesian revolution.KeynesianAccording to Keynesian economics, fluctuations in aggregate demand cause the economy to come to short run equilibrium at levels that are different from the full employment rate of output. These fluctuations express themselves as the observed business cycles. Keynesian models do not necessarily imply periodic business cycles. However, simple Keynesian models involving the interaction of the Keynesian multiplier and accelerator give rise to cyclical responses to initial shocks. Paul Samuelson's "oscillator model" is supposed to account for business cycles thanks to the multiplier and the accelerator. The amplitude of the variations in economic output depends on the level of the investment, for investment determines the level of aggregate output (multiplier), and is determined by aggregate demand (accelerator).In the Keynesian tradition, Richard Goodwin accounts for cycles in output by the distribution of income between business profits and workers wages. The fluctuations in wages are almost the same as in the level of employment (wage cycle lags one period behind the employment cycle), for when the economy is at high employment, workers are able to demand rises in wages, whereas in periods of high unemployment, wages tend to fall. According to Goodwin, when unemployment and business profits rise, the output rises.Credit/debt cycleMain articles: Credit cycle and Debt deflationOne alternative theory is that the primary cause of economic cycles is due to the credit cycle: the net expansion of credit (increase in private credit, equivalently debt, as a percentage of GDP) yields economic expansions, while the net contraction causes recessions, and if it persists, depressions. In particular, the bursting of speculative bubbles is seen as the proximate cause of depressions, and this theory places finance and banks at the center of the business cycle.A primary theory in this vein is the debt deflation theory of Irving Fisher, which he proposed to explain the Great Depression. A more recent complementary theory is the Financial Instability Hypothesis of Hyman Minsky, and the credit theory of economic cycles is often associated with Post-Keynesian economics such as Steve Keen.Post-Keynesian economist Hyman Minsky has proposed an explanation of cycles founded on fluctuations in credit, interest rates and financial frailty, called the Financial Instability Hypothesis. In an expansion period, interest rates are low and companies easily borrow money from banks to invest. Banks are not reluctant to grant them loans, because expanding economic activity allows business increasing cash flows and therefore they will be able to easily pay back the loans. This process leads to firms becoming excessively indebted, so that they stop investing, and the economy goes into recession.While credit causes have not been a primary theory of the economic cycle within the mainstream, they have gained occasional mention, such as (Eckstein & Sinai 1986), cited approvingly by (Summers 1986).Real business cycle theoryMain article: Real Business Cycle theoryWithin mainstream economics, Keynesian views have been challenged by real business cycle models in which fluctuations are due to technology shocks. This theory is most associated with Finn E. Kydland and Edward C. Prescott, and more generally the Chicago school of economics (freshwater economics). They consider that economic crisis and fluctuations cannot stem from a monetary shock, only from an external shock, such as an innovation.There were great increases in productivity, industrial production and real per capita product throughout period from 1870 to 1890 that included the Long Depression and two other recessions. There were also significant increases in productivity in the years leading up to the Great Depression. Both the Long and Great Depressions were characterized by overcapacity and market saturation.。

生态补偿英语

生态补偿英语Ecological CompensationEcological compensation is the payment made to protect and sustain the environment. It is compensation provided for the damage caused to the environment by human activities. It ensures that negative externalities caused by humanactivities are compensated for. This compensation is seen as the cost for the services that the environment provides to humans.Step 1: Understanding the Concept of Ecological CompensationEcological compensation refers to the payment or compensation for the services provided by the environment. These services include the conservation and restoration of natural resources that have been depleted due to human activities. The concept of ecological compensation is aimed at reducing the destructive effects of human activities on the environment while ensuring that the ecosystems are preserved.Step 2: The Need for Ecological CompensationHuman impacts on the environment have led to the degradation of natural resources, such as water and air, and the loss of biodiversity. The need for ecological compensation arises as a result of the negative externalities caused by human activities. Ecological compensation is necessary as it provides incentives for the protection and conservation of the environment.Step 3: The Types of Ecological CompensationThere are two types of ecological compensation:1) Market-Based Ecological Compensation: It refers to the payment made to the affected parties for the environmental damage caused. This type of ecological compensation is aimed at creating a market incentive for the conservation and restoration of natural resources.2) Non-Market Based Ecological Compensation: It refers to the payment made to the affected parties for the non-use value of the environmental services provided. This type of ecological compensation is aimed at accounting for the non-market value of natural resources.Step 4: Examples of Ecological CompensationSome examples of ecological compensation include:1) Payment for ecological services.2) Voluntary ecological contributions.3) Environmental tax credits.4) Financial incentives for ecological conservation measures.ConclusionEcological compensation is an important concept in environmental conservation. The payment for ecological services provided ensures that humans take responsibility for the damage they cause to the environment. The need for ecological compensation arises as a result of the negative externalities caused by human activities. These externalities are compensated for through market-based and non-market based ecological compensation measures aimed at conserving natural resources.。

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普通生态学12 生态系统中的能量流动云南大学生命科学学院生态学与地植物学研究所彭明春本章内容⏹生态系统中的初级生产⏹生态系统中的次级生产⏹生态系统中的分解⏹生态系统中的能量流动生态系统中的初级生产⏹初级生产的基本概念⏹地球上初级生产力的分布⏹初级生产的生产效率⏹初级生产量的限制因素⏹初级生产量的测定方法生产的基本概念⏹生产过程：⏹生产者通过光合作用合成复杂的有机物质，使植物的生物量(包括个体数量和生长)增加⏹消费者摄食植物已经制造好的有机物质(包括直接的取食植物和间接的取食食草动物和食肉动物)，通过消化、吸收在合成为自身所需的有机物质，增加动物的生产量⏹初级生产：自养生物的生产过程，提供的生产力为初级生产力⏹次级生产：异养生物再生产过程，提供的生产力为次级生产力初级生产的基本概念⏹绿色植物通过光合作用合成有机物质的数量称为初级生产量(第一性生产量)⏹初级生产过程植物固定的能量一部分被植物自己的呼吸消耗掉，剩下的可用于植物的生长和生殖，这部分生产量称为净初級生产量(NP) ⏹初级生产过程植物固定的能量的总量称为总初级生产量(GP=NP+R) ⏹群落在一定空间一定时间内所生产的有机物质积累的数量初级生产力⏹某一时刻单位面积上积存的有机物质的量称为生物量(鲜重或干重)⏹绿色植物初级生产量被植食动物取食及枯枝落叶掉落后所剩下的存活部分称为现存量(SC=GP-R-H-D)初级生产地球上初级生产力的分布⏹不同生态系统类型的初级生产力不同⏹陆地比水域的初级生产力总量大⏹陆地上初级生产力有随纬度增加逐渐降低的趋势⏹海洋中初级生产力由河口湾向大陆架和大洋区逐渐降低⏹生态系统的初级生产力随群落的演替而变化⏹水体和陆地生态系统的生产力有垂直变化⏹初级生产力随季节变化不同生态系统的初级生产力TaigaNET PRIMARY PRODUCTIVITY Average net primary productivity in grams oforganic material per square meter per year ofsome terrestrial and aquatic ecosystems初级生产力随群落的演替而变化初级生产力的分布⏹生产力极低的区域：1000kcal/m2.a或者更少⏹大部分海洋和荒漠；辽阔的海洋缺少营养物质，荒漠主要是缺水⏹中等生产力区域：1000-10000kcal/m2.a⏹许多草地、沿海区域、深湖和一些农田⏹高生产力的区域：10000-20000kcal/m2.a或者更多⏹大部分湿地生态系统、河口湾、泉水、珊瑚礁、热带雨林和精耕细作的农田、冲积平原上的植物群落等⏹得到了额外的自然能量和营养物质⏹热带森林面积占5%，生产力占28%⏹水域、河口湾、海藻床和珊瑚礁等面积占0.4%，生产力占2.3%⏹赤道附近区域、北、南半球中温带初级生产的生产效率最适条件下的初级生产力能量(Kcal/m2/d) 效率(%) 能量(Kcal/m2/d) 损失(%) 日光能5000 100.0 不可吸收2780 55.60 可被吸收2220 44.40 反射185 3.70 植物吸收2035 40.70 非活性吸收220 4.40 光合可利用1815 36.30 光合未利用1633 32.66 总初级生产(GP) 182 3.64 呼吸消耗(R) 61 1.22 净初级生产(NP) 121 2.42 (Loomis et al. 1963)不同生态系统类型初级生产效率生产效率=被固定的光能 / 入射光能(1)玉米地(2)荒地(3)Mendota湖(4)Ceder Bog湖陆地E.Transeau,1946 热值 106 Kcal /yr占入射日光能/总生产(%)入射日光能 2043 (4050m 2) 100% 总生产量GP 33.0 1.62 净生产量NP 25.3 1.24 呼吸R7.70.38/23.3用于蒸腾作用 910 44.40 未被利用的日光能 110054.00F. B. Golley, 1960热值 (104 Kcal/m 2·yr)占入射日光能/总生产(%)入射日光能 471 100% 总生产量GP 5.83 1.24 净生产量NP 4.95 1.05 呼吸R0.880.19/15.1玉米地荒地湖泊Meadota 湖Lindeman, 1942 热值 (cal/cm2·yr) 占入射日光能/总生产(%) 入射日光能118872 100%总生产量GP 399+29 0.36净生产量NP 299+22 0.27呼吸R 100+7 0.09/25.0 Ceder Bog 湖Lindeman, 1942 热值 (cal/cm2·yr) 占入射日光能/总生产(%) 入射日光能118872 100%总生产量GP 111.3 0.09净生产量NP 87.9 0.07呼吸R 23.4 0.02/21.0初级生产量的限制因素陆地生态系统⏹辐射强度和日照时间：光强升高，光照时间长，提高产量⏹光合途径：光合作用途径的不同，直接影响初级生产力的高低⏹水：光合作用的原料，缺水显著抑制光合速率⏹温度：温度升高，总光合速率升高⏹营养元素⏹二氧化碳辐射强度Fig. Annual average solar radiation reaching the Earth’s surface.C3、C3植物的光合速率藜红橡木Fig. Photosynthetic rate as a function of light intensity in red oak, a C3 plant, and in pigweed, a C4 plant.降水Fig. Change in net productivity along a precipitation gradient.南极干谷Fig. An Antarctic dry valley.土壤水分蒸发Fig. The rate of net primary production as a function of actual evapotranspiration measured in several grassland sites in the US.温度营养元素营养元素This kind of analysis quantifies the relative limitation effects in a way that allows comparison across nutrients and habitats.二氧化碳Fire 刺激生长与繁殖Fire的影响NDVI⏹归一化植被指数⏹NDVI =（IR-R）/（IR+R）⏹植被分类⏹生物量估算⏹生产力估算水域生态系统⏹光⏹P=R*C*3.7/kP：浮游植物的净初级生产力R：相对光合率k：光强度衰变系数C：水中的叶绿素含量⏹营养物质：N/P⏹缺乏营养物质，海洋生产力偏低⏹肥沃土壤含氮可达0.50%⏹富饶海水含氮仅为0.01%⏹食草动物初级生产量的测定方法⏹收获量测定法⏹氧气测定法⏹二氧化碳测定法⏹放射性标记物测定法⏹叶绿素测定法收获量测定法⏹陆生定期收获植被，烘干至恒重⏹以每年每平方米的干物质重量表示⏹以其生物量的产出测定，但位于地下的生物量，难以测定⏹地下的部分可以占有40%至85%的总生产量，因此不能省略氧气测定法⏹通过氧气变化量测定总初级生产量⏹1927年T.Garder, H.H.Gran用于测定海洋生态系统生产量⏹从一定深度取自养生物的水样，分装在体积为125-300ml的白瓶(透光)、黑瓶(不透光)和对照瓶中⏹对照瓶测定初始的溶氧量IB⏹黑白瓶放置在取水样的深度，间隔一定时间取出，用化学滴定测定黑白瓶的的含氧量DB、LB⏹计算呼吸量(IB-DB)，净生产量(LB-IB)，总生产量(LB-DB)二氧化碳测定法⏹用塑料罩将生物的一部分套住⏹测定进入和抽出空气中的CO2 ⏹透明罩：测定净初级生产量⏹暗罩：测定呼吸量放射性标记物测定法⏹用放射性14C測定其吸收量，即光合作用固定的碳量⏹放射性14C以碳酸盐的形式提供，放入含有自然水体浮游植物的样瓶中，沉入水中经过一定时间，滤出浮游植物，干燥后在计数器测定放射活性，然后计算：14CO/CO2=14C6H12O6/C6H12O62⏹确定光合作用固定的碳量⏹需用“暗呼吸”作校正叶绿素测定法⏹植物定期取样⏹丙酮提取叶绿素⏹分光光度计测定叶绿素浓度⏹每单位叶绿素的光合作用是一定的，通过测定叶绿素的含量计算取样面积的初级生产量生态系统中的次级生产⏹次级生产过程⏹次级生产量的测定⏹次级生产的生态效率个体内的能量过程次级生产量的生产过程未捕获(876.1g) 猎物种群生产量(886.4g)被捕获(10.3g)被吃下(7.93g)I未吃下(2.37g) 未同化(0.63g) 同化(7.3g)A净次级生产(2.7g)P 呼吸(4.6g)R次级生产量能量收支⏹C=A+FU⏹C：动物从外界摄食的能量⏹A：被同化能量⏹FU：排泄物⏹A=P+R⏹P：净次级生产量⏹R：呼吸能量次级生产量的测定⏹用同化量和呼吸量估计生产量(用摄食量扣除粪尿量估计同化量)：P=A-R=(C-FU)-RC：动物从外界摄食的能量，A：被同化能量，FU：排泄物，R：呼吸量⏹用个体的生长和繁殖后代的生物量表示净生产量:P=Pg+PrPr：生殖后代的生产量， Pg：个体增重次级生产的生态效率⏹消费效率：⏹食草动物对植物净生产量的利用⏹植物种群增长率高，世代短，更新快，被利用的百分比高⏹草本植物维管束少，能提供较多的净初级生产量⏹浮游动物利用的净初级生产量比例最高⏹食肉动物对猎物的消费效率研究较少⏹脊椎动物捕食者50～100%，无脊椎动物捕食者25%⏹同化效率⏹草食、碎食动物同化效率低，肉食动物高⏹生长效率⏹肉食动物的净生长率低于草食动物⏹不同动物类群有不同的生长效率生长效率食虫类林德曼效率生态系统中的分解⏹分解过程的性质⏹分解者生物⏹资源质量⏹理化环境对分解的影响分解过程的性质⏹概念：⏹死有机物质的逐步降解过程⏹将有机物还原为无机物，释放能量⏹意义：⏹建立和维持全球生态系统的动态平衡⏹通过死亡物质的分解，使营养物质再循环，给生产者提供营养物质⏹维持大气中CO2浓度⏹稳定和提高土壤有机质含量，为碎屑食物链以后各级生物生产食物⏹改善土壤物理性状分解作用的三个过程⏹碎化：把尸体分解为颗粒状的碎屑⏹异化：有机物在酶的作用下，进行生物化学的分解⏹从聚合体变成单体(如纤维素降解为葡萄糖)⏹进而成为矿物成分(如葡萄糖降为CO2和H2O)⏹淋溶：可溶性物质被水淋洗出，完全是物理过程影响分解过程的因素⏹分解者生物⏹资源质量⏹理化性质。