Sonderdrucke aus der Albert-Ludwigs-Universität Freiburg ALBRECHT KESSLER The palaeohydrology of the Late Pleistocene Lake Tauca on the Bolivian Altiplano and recent climatic fluctuations Originalbeitrag erschienen in: J. C. Vogel (Hrsg.): Late Cainozoic palaeoclimates of the Southern Hemisphere : proceedings of an international symposium held by the South African Society for Quaternary Research in Swaziland, 29 August - 2 September 1983. Rotterdam [u.a.]: Balkema, 1984, S. 115 - 122 SASQUA Intrntnl Sp Szlnd 2 At 2 Sptbr 8 The palaeohydrology of the Late Pleistocene Lake Tauca on the Bolivian Altiplano and recent climatic fluctuations AEC KESSE Unvrttt rbr, Grn ASAC. Appln, th tr bdt t th plhdrl f th t ltn (2 00 000 n th Altpln (Sth Arn And, vrl r dd t h h th lt ndtn t hv hnd n prn th th rnt lt n rdr t th frtn f th pll pbl. It hn tht prpttn t hv nrd b t lt 0 % n th ntr Altplnbn n prn th tht f td. h xpl f th rnt tr bdt flttn f t h tht th nd tn drn th prd n bt b xplnd b thrd hft f th tphr rltn blt n th r f th Alt pln. IOUCIO h rvnlvn Altpln ld tprph dprn (. Sn th nrthrn prt hhr nd ttr, t drnd fr nrth t th b th dr rvr hh fl nt ld l, th p. d th thrn Altpln l nld th Slr f Cp nd Un. h nvttn b Srvnt nd nt (8 hd tht thr ltrn trnrn hv rrd n th Mddl ltn, hh ntd th thr bn t fr lr l. h ll , th lt n, frd n th t ltn btn 2 00 nd 000 . It vrd 4 000 2 nd hd xl dpth f 60 . bt 0 000 hd bn rdd t pprxtl th z f p. rn th ln thr r nl ll flt tn f th l lvl. Klr (66 rprtd n rnt vrtn nd th frtn f n l (UrUr n th thrn Altpln. Mrr nd l ( r bl t prv tht th t Gl tn n th Crdllr d lnt nd th Ql p n th r f th nrthrn Altpln lntd t btn bt 28 000 nd 4 000 . A rthr nr rdvn f th Ql p n prr bt 00 nd lntd bt 000 (nn II rn. 0 000 t hrdl, f t ll, lrr thn t td. h n ln dprn drn th nn II rdvn prbbl nt r thn 00 . Evdn f t ltn lr dvn h l bn fnd n thr prt f th Altpln thnt r (Crdllr d Aplbb, • br (82 Crdllr l, 0. h nn II rdvn n l b prd th th xn tp prfl brvd n th C r f t Antrt (r t l. h r hrnl ndt rltvl ld prd fr 000 t 000 . h flln rntrtn f th lt drn th nn II rdvn n th tr bdt tn fr . h lthd h lrd bn ttd n nr ld l (.. b pld Sndr nd nbn 62 Klr 6 Grv nd lln 6 d 6 Gll 0 tzr t l. Ktzbh 80 ). Sn lrd xtd drn th nn II rdvn, t prn drn th prd nnt b xplnd b n ddtnl rnff fr ltn lr f th bn. It rn t b d t hn n vprtn ndr prpttn. In n t rr bl tht drn th ll rtrt fr ptn nn II t p tn nn I btn 000 nd 0 000 drd t dpt bn ddtnll fd b ltn lr drn th prd. QUAIAIE ESIMAES O AS EAOAIO A ECIIAIO O E AAEOAKE AUCAEIO In rdr t llt th tr bdt f ll , th Alt pln dvdd nt vrl r (. nd bl . h fr fr th rnt ttn r fr Klr (6, 0 nd Klr nd Mnh (68. r . t ltn nd th Altpln (r, l v rdn t Srvnt nd nt (8. 6 bl . hdrll nd ltll dt f th Altpln. Ar nt nt pr. rnff (km') (r ffnt Ar f nrthrn 22 00 0. Ar f thrn 20 00 0.b Cthnt r f tht thnt r f dr rvr 00 0.22 0.0 Cthnt r f dr rvr tht thnt r f t 0 20 0.4 0.0 Ar f t (t ltn 00 0. Cthnt r f t (t ltn 48 400 0. 0.2 h n nnl tr bdt f ld l t lbr n b xprd b th tn C E = ° hr L th nnl prpttn nt th l, th n ttl nnl rnff fr th thnt r nd E th n nnl l vprtn. In th vr td th nr n rnff fr th thnt r hh rrd tthr th dr n vptrnprtn d t tprtr dprn, lltd th th tr bdt tn f th thnt r: Rc = Pc Ec hr th nnl prpttn nt th thnt r, EC th nnl vptrnprtn fr th thnt r. Ardn t dr b Wndt ( th nr n rnff hn th prpttn nt th thnt r nr pl n nr n rltv hdt (U f th r n th bn (bl 2. bl 2. h hn n th rnff ffnt K = c /Pc dpndnt n prpttn nt th bn c (rdn t Wndt . (r 20 0 40 0 60 0 80 0 00 0 20 0 0.00 0. 0.20 0.26 0. 0.6 0.40 0.40 0.40 0.0 0.0 0.600 Evprtn fr th l nd t hn dpndnt n th rf tprtr nd rltv hdt f th r lltd th n rdn bl frl: E = f((Q = f((Q hr ntnt, f( fntn f th nd vlt, Q th vpr prr t th tr rf nd th vpr prr 117 f r. h dr n vptrnprtn f th thnt r th dr n tprtr lltd n th ftr th vprtn fr th l rf. r ttn th rnt l vprtn f th Altpln th vl fr t d, nl E = .48 ( pr r. t n th thrn Altpln drr, E prbbl ht hhr. r th rn th flln lltn rprnt th nl ndtn fr n nr n prpttn. h xl tprtr dprn fr th nn II rdvn (= ° C lltd fr th n ln dprn (00 nd th tprtr rdnt f th r nr th rnd (0.80. ° C00 , rdn t Klr 6. ESUS O E CACUAIOS h flln ndvdl ll dntrt th ntvt f th dl. bl h ht prnt f th nnl tr ppl ld b rprntd b th prpttn nt (A, th rnff fr th thnt tht dhr fr t (, nd th dhr fr t (C n h . C : A = 0, AE = 0, A = O. Wht ld hv hppnd f th ll hd bn bjt t td lt ndtn, tht , f hn n prpttn, vprtn nd tprtr hd nt rrd? Or lltn h tht th l ld hv drd p n bt 0 r. In th xpl th prpttn nt th p 2% (bl . C 2: A 0, AE = 0. h nd tn : h h t th prpttn n th ntr bn b nrd n prn th td ndtn fr th ll t xt? h nnl prpttn nt ld hv t b nrd b 8% ll vr th thnt r. A bl h, th dhr fr t ld thn ppl 0% f th tr fr . C : AE 0, A 0, A = 0. A lrd ntnd, tprtr dr f ° C n b ddd fr th n ln dprn drn th nn II rdvn. h ndt dr n vprtn f 8% n prn th th t tn td. It n l b d tht prpttn nd rltv hdt hv nt hnd. h t tht th xtn f th ll nt rd. It ld dppr n bt 00 r. h tr ppl f th ll ld b rltvl ll dtrbtd n ll thr pnnt. C 4: AE 0, A 0, A O. h bd n th ndtn n . h dft pntd b n nr n prpttn. In th f dr n vprtn b 8% d t th tprtr, prpttn n th ntr bn t b nrd b 40% n rdr t rnt th xt n f th ll . 8 C : A 0, A 0, A 0, Ad 0 (. In lltn 4 t nt nt tht th prpttn r n nr n th rltv hdt f th r l t th rnd ( n th thnt r. In rdr t hhtn th nl ndtn fr pbl nr n prpttn t ll l b d tht th rltv hdt vr th rf nrd b % prd th td ndtn. n th tprtr hn nt ndrtn th ld n dr n E b ttl f 2%. h nr nr n prpttn (A ld thn tll b h 0%. bl . Mn nnl tr ppl fr th ll n prnt. A rpttn nt nff fr th thnt tht dhr fr t C hr f t A C 2 4 4 C 2 2 8 0 C 39 26 35 C 4 2 2 46 C 0 24 46 h rlt n b rzd fll: h xtn f th ll nnt b xplnd tht n n nr n prpttn f t lt 0% n th ntr bn. Althh th dhr fr t f ndr prtn fr th tr bdt f th thrn Altpln td, t pld vr prtnt rl drn th t ltn fr th ll (bl , . EECIOS AOU E AAEOCIMAE It h bn pntd t rptdl (.. n 8 lhn 8 Mrr 8 Slnr 8 Strtrrtt nd brt 8 tht drn th prd fr 8 000 nd 400 (Sthrn phr thrl x thr n nl r n tprtr n th t hphr.