the quaternary of colombia
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Henry Hooghiemstra (1), Vladimir Torres (1,2), Raul Giovanni Bogotá-Angel (1,3), Mirella Groot (1), Lucas Lourens (4),
Juan-Carlos Berrio (1, 5) & Project members #
(1) Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Netherlands(2) current address Exxon Mobil, Houston, USA
(3) current address Universidad Distrital Francisco José de Caldas, Bogotá, Colombia(4) Geosciences, University of Utrecht, Netherlands
(5) current address Dept. of Geography, University of Leicester, UK
DEBI
Long Records of Environmental and Climate Change
The 2,250,000-yr long record from the Bogotá basin
Age model development
Basin development
Biome evolution
are crucial to document the series of ice ages that characterise the Pleistocene. While in the northern hemisphere ice sheets expanded and shrunk periodically, in the tropical mountains the altitudinal vegetation distribution shifted downslope during relatively cold glacials and stadials and upslope during relatively warm interglacials and interstadials. This poster focus on development age models for the sediments in the basins of Bogotá and Fúquene (Fig. 1), the climate history of the northern Andes and the evolution of its high elevation biota.
In the Bogotá basin (4°N, 2550 m elevation) 586 m of sediments have been cored. The 2200-sample record of grain size distributions shows changes in sedimentary environments (1). The pollen record starts at 540 m core depth and samples at 20-cm increments along the core provide a record of 2100-samples (1). The record of aquatic vegetation re!ects changes in water depth. The record of trees, shrubs and herbs shows changes in the vegetation that covered the mountains around the lake.
The 357-m deep Funza-1 core (2) and the 586-m deep Funza-2 core (1) have been coupled at the "rst appearance event of Alnus (Fig. 2). Changing percentages of arboreal pollen (AP%) in the composite record Funza09 (540-1.6 m) show altitudinal shifts of the upper forest line (UFL) (3). Using a lapse rate of 0.6°C/100 m UFL displacement and a mean annual temperature (MAT) at the UFL of ~9.5°C paleo-temperatures have been calculated.During warm interglacial conditions the tree Alnus mainly forms swamp forest around the lake re!ected as high peaks in the AP% record. The sequence of Alnus-based interglacials have been matched with the marine record of glacial-interglacial cycles as shown by the LR04 benthic #18O stack record (Fig. 3) (4). The immigration event of Alnus has been dated 1.018 Ma. We used
cyclostratigraphy to develop the age model for the lower part of the Funza09 record. Frequency analysis in the depth domain shows peaks of 9.5-m and 7.6-m (Fig. 4). Wavelet analysis shows a stable presence of the 9-m frequency band which could be robustly linked obliquity as the main driver of climate change. The age model shows the Funza09 record re!ects the period from 2,250,000 to 27,000 years BP (Fig. 5).
The AP%-based temperature record re!ects marine isotope stages (MIS) 85 to 3 (Fig. 6 lower panel). The record of aquatics shows deep-water vs. shallow-water conditions re!ecting climate change superimposed by e$ects of basin evolution (Fig. 6 top panel). In the period of 2.25-1.47 Ma wetlands, !uvial channels and swamps prevailed. The basin !oor subsided rapidly between 1.47 and 1.23 Ma and a lake developed. Between 1.23 and 0.86 Ma lacustrine sediments accumulated in waters up to 50 m deep. Water depth was lower during the last 860,000 years but !uctuated in conjunction with the 100-kyr dominated glacial-interglacial cycles of the middle and late Pleistocene (3). Around 27,000 BP the lake disappeared probably because the Bogotá basin became over"lled with sediments.
The Bogotá basin record shows 5 stages in the evolution of montane forest and páramo vegetation (Fig. 6 middle panels) (3). (1) Period 2.25-2.02 Ma: vegetation above the UFL was poor in species (protopáramo). Aragoa occasionally reached high abundance. In the Andean forest Podocarpus increased in abundance. Proper lake conditions had not yet developed. In absence of Alnus, Morella (Myrica) formed swamp forest and thickets on the basin !oor.(2) From 2.02 Ma (MIS 75) onwards increasing proportions of Aragoa, Ericaceae and Hypericum indicate that shrub vegetation developed as a structural transition zone between upper montane forest and herbaceous páramo. Polylepis, originating from the southern Andes, started its presence 2.1 Ma (MIS 78).(3) From 1.58 Ma (MIS 54) onwards Borreria had developed as an element of the upper montane forest and was no longer an exclusive constituent of open vegetation. The páramo reached more closely its modern structure and taxonomic composition. In the montane forest the share of Podocarpus decreased.(4) After the closure of the Panamanian Isthmus several Holarctic trees immigrated into South America. Alnus immigrated 1.01 Ma (MIS 29). In the swamp forest around the lake Alnus replaced Morella (Myrica). On the north Andean slopes Alnus changed the composition of montane forests.(5) At 430,000 yr BP (MIS 12) Quercus (oak) arrived in the northern Andes and changed forest composition dramatically. At high elevations Quercus competed with Weinmannia and Podocarpus. Near the UFL Quercus
partially replaced Polylepis. However, Quercus expanded slowly and reached as late as 240,000 yr BP (MIS 7) signi"cant proportions. Most of the Pleistocene vegetation assemblages have no modern analogue. However, modern ecological constraints of suites of taxa allow a robust reconstruction of environmental and climate change.
Funza
Fúquene
Bogotá Basin
Fúquene Basin south
Fúquene Basin north
100
0
50
100
150
200
250
300
350
400
450
500
550
Alnus
Gap in Funza-2 core recovery
Funza-2
m
100
Alnus
Funza-1
Subandean forest
Andean forest
Subparamo
Páramo
Arboreal Pollen (AP)
Many gaps andlow pollen recovery
0
50
100
150
200
250
300
350
400
450
500
550
m0 20 40 60 80 100%0 20 40 60 80 100%
1800
200 2800
Funza09
0 20 40 60 80 100%0
50
100
150
200
250
300
350
400
450
500
m
Take
n fro
m F
unza
-2Ta
ken
from
Fun
za-1
0 200 400 600 800 1000 1200Age (ka)
5.0
4.5
4.0
3.5
3.0
OD
P Si
tes
846
& 84
9
0
40
80
120
160
Alnu
s (%
)
3
2
1
0
-1
-2
18O
Med
iterra
nean
0
40
80
120
160
Alnu
s (%
)
visual tiepoint
1
5.1
5.5
7.1 7.5 9.1
9.311
1315.1
15.517
19 21
23
25
2927
31
33
35
3
7.3
8.5
18.3
Alnus
Alnus
18O
excl
. Que
rcus
excl
. Que
rcus
O-tuning: Arboreal Pollen excluding Alnus and Quercus (detrended)
41ky
100ky
23ky
41ky
100ky
23ky
0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400
ODP Sites 846 & 849
5.2
4.8
4.4
4.0
3.6
3.2
2.8
18O
(per
mil)
-40
-20
0
20
40
AP (%
, det
rend
ed)
eccl
. Aln
us a
nd Q
uerc
us
4
168
3264
128256512
4
168
3264
128256512
0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200
0 50 100 150 200 250 300 350 400 450 500Depth (m)
-40
-20
0
20
40
AP (%
, det
rend
ed)
eccl
. Aln
us a
nd Q
uerc
us
Funza: Arboreal Pollen excluding Alnus and Quercus (detrended)
1
42
8163264
128
0.5
~20m (100ky)
~8m (41ky)
Age (ka)
Perio
d (m
)Pe
riod
(ky)
Perio
d (k
y)
~4m (23ky)
0003000200010Age (ka)
0
200
400
600
Dep
th (m
)
10
20
30
40
50
60
Sed.
rate
(cm
/kyr
)
P-tuning
Hooghiemstra et al., 1993
O-tuning
O-tuning
P-tuning
-30
-20
-10
0
10
20
30
AP(%
, det
rend
ed) ex
cl. A
lnus
and
Que
rcus
0
40
80
120
160
Alnu
s &
Que
rcus
(%)
0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400Age (ka)
Quercus
Alnus
5
79 11
13
15
17 19 21 25 37
47
49
787064
-3.0
0.0
3.0
3.0
3.5
4.0
4.5
5.0
Medit
erra
nean
!18 O
ODP
Site
s 846
& 8
49!1
8 O
5
7
911
13
15 19
612
7793
81
82
87
64
91
78
72
637321
25
23
22
31
35
33
29
37
39
4749
5155
59
Extrapolation Visual match Astronomical tuning
40
80
120
40
80
120
Ande
an fo
rest
Subp
áram
o &
Pára
mo
PodocarpusMyrica
BorreriaAragoa
Hypericum Polylepis
Proper Páramo and Andean forestwith no Oak
Andean forest with no Alder and no Oak Development of shrub Páramo ProtopáramoDevelopment of Oak forest
Sele
cted
taxa
(%)
excl
. Aln
us a
nd Q
uerc
us
0
100%
20%40%60%80%
Low water stands. Mainly fluvio-lacustrine and swamp deposits.Development of proper lake
Highest lake levelsFluctuation of lake levels closely related to glacial/interglacial cycles
Ludwigia & Myriophyllum
Hydrocotyle
Cyperaceae
Isoëtes
Aqua
tic ta
xa in
dica
ting
lake
leve
l
Fig. 1
Fig. 2
Fig. 3
Fig. 4 Fig. 5
Fig. 6
DEBI
The 284,000-yr long record from the Fúquene basin
Age model development
Conclusions
Selected ReferencesAcknowledgements
Tropical montane forest and tropical alpine grassland (páramo) ecosystems are sensitive to variations in global ice volume and respond to global climate change with signi"cant altitudinal migrations. A one-to-one coupling between changes in tropical MAT and the North Atlantic climate variability at both orbital and millennial time scales is shown. Century-scale changes of 2-3.5°C during MIS 3-4 (Pleniglacial) and during previous glacial MIS 6, and extreme changes of up to 10±2°C at the major glacial Terminations are shown. Long continental records analysed at sub-centennial resolution show the dynamic history of terrestrial biomes and allow to assess current and projected future climate change in a Pleistocene framework. However, developing such records is still an academic challenge.
(1) Torres V et al. Palaeogeography Palaeoclimatology Palaeoecology 226, 127-148 (2005); (2) Hooghiemstra H. Dissertationes Botanicae 79 (1984); (3) Torres V et al. Quaternary Science Reviews 63, 59-72 (2013); (4) Lisiecki LE, Raymo ME, Paleoceanography 20 PA1003,doi:10.1029/2004PA001071 (2005); (5) Sarmiento G et al., Geomorphology 100, 563-575 (2008); (6) Bogotá-A RG et al. Ch. 5 in PhD thesis (2011b); (7) Groot MHM et al., Climate of the Past 7, 299-316 (2011); (8) Groot MHM et al., Quaternary Geochronology (2014). http://dx.doi.org/10.1016/j.quageo.2014.01.003; (9) Van Geel B, Van der Hammen T, Palaeogeography Palaeoclimatology Palaeoecology 14, 9-92 (1973); (10) GRIP-Members, Nature 364. 203-207 (1993); (11) Jouzel J et al., Science 317, 793-797 (2007); (12) Van der Hammen T, Hooghiemstra H, Global and Planetary Change 36, 181-199 (2003); (13) Mommersteeg HJPM, PhD thesis, University of Amsterdam (1998); (14) Vriend, M et al., Netherlands Journal of Geosciences 91, 199-214 (2012); (15) Bogotá-A RG et al. Quaternary Science Reviews 30, 3321-3337 (2011a).
We greatly acknowledge the contributions to the Funza and Fúquene Projects by A. Betancourt, L. Contreras, S. Gaviria, C. Giraldo, N. González, J.H.F. Jansen, M. Konert, D. Ortega, J.O. Rangel, C.A. Rodríguez-Fernandez, G. Sarmiento, E. Tuenter, P.C. Tzedakis, J. Vandenberghe, T. Van der Hammen, M. Van der Linden, J. Van der Plicht, B. van Geel, M. Vriend, S.L. Weber, W. Westerho$ and M. Ziegler. These Long Continental Record projects were "nancially supported by NWO (The Hague), WOTRO, (The Hague), AlBan (Madrid), NUFFIC (The Hague), IBED (University of Amsterdam), INGEOMINAS (Bogotá) and COLCIENCIAS (Bogotá).
This poster was designed by Jan van Arkel/IBED/University ofAmsterdam
We revisited the age models of pollen records Fq-3 (12, 15) and Fq-7C (13) with the new approach of cyclostratigraphy and we obtained a basin-wide biostratigraphy (15) constrained in time (Fig. 10). We recognised periods with distinct sediment compositions (14) and abundance of geochemical elements (6).
For a comparison of temperature records we show Greenland #18O ice core record (10) for the past 180,000 years and the record from Antarctic core Epica Dome C (11) and our near equatorial record Fq-BC (Fig. 9) (7). During the last 130,000 years ice cores show 28 millennial-scale climate oscillations (Fig. 9, bottom panel), known as Dansgaard-Oeschger (DO) cycles. Most DO cycles are re!ected in equatorially located Fq-BC pollen record (Fig. 9, top panel) The clear signature of the Younger Dryas (constrained by 14C dates), and the interstadial DO cycles 8, 12, 14, 19 and 20 in the reconstructed MAT record suggest an unprecedented North Atlantic-equatorial link.
Sediments centrally located in the lake contain low percentages of carbon preventing robust 14C-dating (8). Cyclostratigraphy is a challenging alternative. Frequency analysis of the AP% record in the depth domain show peaks at 907 and 2265 cm. Wavelet power spectra show that the strengths of these frequencies are stable throughout the core in depth and time. These frequencies were explored and appear to be linked to the obliquity (41-kyr) and eccentricity (~100-kyr) cycles of orbital forcing of climate change (Fig. 8). Remarkable is the absence of a clear imprint of the precession-related 21-kyr cycle (7). Fig. 8A shows the Fq-9C AP% record as raw data and Fig. 8B as a detrended and interpolated depth series overlain by a ~9 m Gaussian "lter. Fig. 8C shows the LR04 benthic #18O stack record (4) overlain by a Gaussian "lter centered at the 41-kyr cycle. We correlated the "ltered 9-m signal in Fq-9C to the "ltered 41-kyr obliquity-related component of the LR04 benthic #18O stack record to develop the age model. The 4768-points Fq-9C record re!ects the interval from 284,000 to 27,000 yr BP. The Fq-9C record was extended to late Holocene time by adding part of the Fq-2 pollen record (9): the Fúquene Basin Composite (Fq-BC) record. The connection with modern instrumental data allows to calculate mean annual temperatures (MAT) throughout the record.
In Lake Fúquene (5°N, 2540 m), a colluvial damm blocked lake (5), the upper 60 m of sediments have been collected from a !oating raft in two parallel cores (Fig. 1). Downcore measurements at 1-cm increments revealed multiple 4768-points records. Pollen and carbon content show biome changes in the area and grain size distributions and XRF-based geochemistry show the abiotic changes in the basin. Downcore changes in lithology (5), Fe and Zr (6) in cores Fq-9 and Fq-10 allowed to develop the composite record Fq-9C (7). Geochemical records show changes in erosion and sediment transport in the basin. Downcore grain size distributions show changing sedimentary environments (Fig. 7). Downcore aquatic pollen show changes in water-levels (Fig. 7). Downcore regional pollen show temperature-driven changes in the altitudinal vegetation distribution.
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