Energy Flow & Efficiency

Energy Flow & Efficiency - 1/15/12 Energ Flow...

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Unformatted text preview: 1/15/12 Energ Flow & Efficienc ENERGY FLOW & EFFICIENCY We are stardust, m illion- ear old carbon J Energ is eternal delight (W B M ) ) GENERAL PRINCIPLES Ecological Thermod namics A - T , , : (1) ; (2) ( , ) ; (3) ( ) F , ) H ( & ) ( , / , T ( ) T m aterials c cle , energ flows E ; ) , , ,& ( ( ) A , ( , B ( ) , , , ( , & ; Australopithecus .) , F ), " " L V , & ( ) courses.washington.edu/anth457/energ .htm 1/9 1/15/12 Energ Flow & Efficienc T trophic levels (" B " G ) : 1) ( 2) ( 3) ( ) & , , - , ) 4) , .) , ( , 50% !) I , ( , , , ); - food webs B , S " & m aintenance ( ") growth ( H ), = p ram ids : [ ee Diag am] 1. , & ; 2. 10% ( ), ; 3. ( - ) . 10% , 4-5 ( ) B , , , P A R L C B F A ") , , ( T ( "W , ) - ( efficient -- ) courses.washington.edu/anth457/energ .htm 2/9 1/15/12 Energ Flow & Efficienc Energ Efficienc and Adaptation I , " efficienc " I , , : 1. O / = 2. N I / = E /E = (E -E )/T ( . ., / , I' " T , &M C " (V ) ) ' 1975) ;) ; ) T : 1. A , ( is ) ( , ; ( 2. O are , ) ) - , 3. I , T 3 , ( 1) ' H 1989 ): energ (" 2) tim e - ") (" 3) - ") risk ( . ., T ) : 1) S ( - ) , / ( I courses.washington.edu/anth457/energ .htm ) ( . ., - , 3/9 1/15/12 Energ Flow & Efficienc a ic acid f ac ) ha i a a i c ea e i a e e g ha e ed i he a e a f f agi g i e, hi i e i i c ea ed e d c i e cce , a d he i ai i i e ead h gh ch ice ( ea i g bia ) a a e ec i f e e (if chi d e ad ae ech i e ) Thi i e a e f energ -lim ited ada i e beca e i i c ea e he Wha ab )S c ca e ea i gf a i , he e i c ea e i efficie c a e e g a ai ab e f c i ei he e e e g i not i i i g? ai fa fh c ic ai ha ade a e f d , b e gage i e i i ba ed i a , ce e ia fea i g, e c. I c ea e i a a m o u n t f e e g ca fd ") B f e e g ca ' e e h gh e e i ch a ede i eg i g& ce i ica a d/ i a ca ee ed ada i e, i ce ai d i gc ' i e- e e g - i i ed (i.e., "ade ae a e f d, he 'd bab i e be ab e he ca de e e i e ad a ci g hei N e ha a e h ad a e efficie d ci ech i e c i be ab e d ce sam e am ount f e e g i e i e, f eei g e i e hich ca be a ca ed c i a i g a i a ce , a c i i g e i g i e d g e , g a i i g a , e c. Thi i a e a e f tim e-lim ited ca e, he e i c ea e i efficie c f e e g ca e i ada i e beca e i e f eed f ee i g e e g eed ca be de ed he a ed ada i e ac i i i e (Wi gai i g highe a id ia cie ie , b F i a ca e i e )S eag e e g - i i ed ead e' i ai he e e e g ac f ca e he de i e- i i ed H e e , he di g i e ai de , e e hea A e e eg i c ea ed e d c i e cce ? P bab , a ea e e a i i g ha i ae i c e) i ii ha ade e g ea e i e) ai d ad f ei e i e, bidi (e.g., a b ech i e, , ca e b eed ha ed ced he i e eeded igh be ada i e (b ed ci g i e e ed he e i ) Thi i a ca e he e i c ea ed e e ge ic efficie c i ada i e beca ia a ea fe e g be ca ed i e i e, hich i risks a i ica ade courses.washington.edu/anth457/energ .htm a e da a e a e ce f each f he e 3 c ei he hb e e ha e a ea f e (a i i e- i i ed ca e) ed ce ea ai I a , he e a e 3 diffe e c di i de hich i c ea ed efficie c i e e g ca ada i e; e f he e = e e g - i i ed ("h ge ") We ac e- e ai i c ea ed risks: aef f i di i ( ei f4h 4/9 1/15/12 Energ Flow & Efficienc ) H , , 3 A a if ( , , ); ( . ., , ) APPLICATION TO HUMAN POPULATIONS A T - , W Q F , P (N ) , Methodolog T ( , ); 1) ( ); 2) 3) T , L - C - ; ( ), C ( - ( , , F ), !) ( , ; M courses.washington.edu/anth457/energ .htm - ) , , , 1.1 / .( 65 ) 5/9 1/15/12 Energ Flow & Efficienc to 15+ kcal/min. (logging, X-country skiing); adult female rates avg. 75% of males (due to smaller body size, plus lower proportion of energy-expensive muscle) To quantify caloric value of production outputs, must weigh crops harvested or caught, establish edible portion, and then measure caloric content (via controlled combustion or using published references) If employ good sampling methods, and if know demographic structure, one can extrapolate from observed/measured households to larger population of interest Nu oa case stud One of the most careful and interesting studies of human energy flow = Quechua speaking Indians of Nu oa, highland Peru (in heart of Inca homeland), conducted by Brooke Thomas and others in 1960's and 70's [This will be presented in class, with slides] Tables of Nu oa data] TRENDS IN ENERGY EFFICIENCY Intro Various scholars have proposed that human subsistence and energy use exhibit several general historical or evolutionary trends: 1) an increase in am ount of energy harnessed per capita 2) an increase in efficienc (returns per unit labor) 3) a tendency for human population density to increase to maximum possible in a given environment with a given technology (carrying capacity) Here we examine the first 2 proposed tendencies, deferring consideration of 3rd to next section of course (on "population ecology") Amount of Energ Table provides one estimate of growth of energy flow per capita at various "stages" of human biological and cultural evolution; same data illustrated in graph Systems powered only by metabolic energy (muscle power) can harness only energy consumed as food: ca. 2000 kcal/person/day consumed, of which bulk must go to maintenance (keeping people alive) rather than work courses.washington.edu/anth457/energ .htm 6/9 1/15/12 Energ Flow & Efficienc A , ; , , ( ) O , ( 2 & , , , A ( , , : .), ( , .) - & , , .) I , ( ), T ; 40% (V . 1986) ! O ; O ( ) ( / ) - O ( ' ) Efficienc of energ harvest M , / A ( ., / : [TABLE 2] (N , - , ., & .), , ) B : 1) S : , . ( H 4 1989 , ) 2) I (! K =6 - , ' 3) U / ( : , courses.washington.edu/anth457/energ .htm ;T ;C ; ' = .) ; U.S. = ) ( , = , ) . 7/9 1/15/12 Energ Flow & Efficienc ( ) I no , , ' , ( , . , ) 4) W ?T ; ), ( . ., d e cl i n e B & T ?T ?O / 5) C , ( ) N 4 ( . .T , = 130 !K , = 10 T ) T , , ( T , / ), " D " T : I nnovations that are adaptive for individuals w hen the arise (and thus spread in the population) ma not be so in long run or in aggregate ( . ., , ); , ( ) B ( W , , ? ) ' ? P . P , (" ( "), ) , & , T , : courses.washington.edu/anth457/energ .htm 8/9 1/15/12 Energ Flow & Efficienc Co o k. E. (1971) Th e flo w o f en erg in in d u s trial s o ciet . S cien tific America n 224(3): 134-48. Hames , Ra mo n d B. (1989) Time, efficien c , an d fitn es s in th e A ma o n ian p ro tein q u es t. Resea rch in Eco n o mic An th ro p o lo g 11:43-85. Harris , M arv in (1975) Cu ltu re, Peo p le, Na tu re, S eco n d Ed itio n . New Yo rk: Cro well. Little, M ich ael A . an d Geo rg e E.B. Jr. M o rren (1976) Eco lo g , En erg etics, a n d Hu ma n Va ria b ilit . Du b u q u e, Io wa: W .C. Bro wn . Pimen tel, Dav id , et al. (1973) Fo o d p ro d u ctio n an d th e en erg cris is . S cien ce 182:443-49. Rap p ap o rt, Ro A . (1971) Th e flo w o f en erg in an ag ricu ltu ral s o ciet . S cien tific America n 224(3):116-32. Th o mas , R. Bro o ke (1973) Hu ma n Ad a p ta tio n to a Hig h An d ea n En erg Flo w S stem. Occas io n al Pap ers in A n th ro p o lo g , (No . 7), Dep artmen t o f A n th ro p o lo g , Pen n s lv an ia State Un iv ers it Th o mas , R. Bro o ke (1976) En erg flo w at h ig h altitu d e. In Ma n in th e An d es, ed . P.T. Baker an d M .A . Little, p p . 379-404. Stro u d s b u rg , PA : Do wd en , Hu tch in s o n an d Ro s s . Va d a, A n d rew P. an d Bo n n ie J. M cCa (1975) New d irectio n s in eco lo g an d eco lo g ical an th ro p o lo g . An n u a l Review o f An th ro p o lo g 4:293-306. Vito u s ek, Peter M ., et al. (1986) Hu man ap p ro p riatio n o f th e p ro d u cts o f p h o to s n th es is . Bio S cien ce 36(6):368-373. Vito u s ek, Peter M ., et al. (1997) Hu man d o min atio n o f th e earth 's eco s s tems . S cien ce 277:494-499. W in terh ald er, Bru ce, Ro b ert Lars en , an d R. Bro o ke Th o mas (1974) Du n g as an es s en tial res o u rce in a h ig h lan d Peru v ian co mmu n it . Hu ma n Eco lo g 2:89-104. courses.washington.edu/anth457/energ .htm 9/9 ...
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This note was uploaded on 01/16/2012 for the course ANTH 457 taught by Professor Smith,e during the Fall '08 term at University of Washington.

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