Dr. Min RAN, Dr. Zhaodong FENG
Department of Geography, Henan University
CLIMATE CHANGE OF THE LAST GLACIAL IN
KAZAKHSTAN
In this study we focus on two loess sections in Kazakhstan to
reconstruct the paleoclimate change during the last glacial and to
explore the possible influence on cultural evolution. The Valikhanov
loess section is situated in Valikhanov Valley near the City of
Zhanatas in south-central Kazakhstan dominated by steppe
vegetation and the landscape in the area is nearly completely mantled
with loess deposits. The section is 700 cm thick and 140 samples
were taken at intervals of 5 cm for
13
C
org
analysis. Six AMS
14
C dates
52
were obtained from this section and the result showed that it spanned
the past 32,000 yr. The Tramplin section is a naturally exposed
section on the third terrace of the Talgar River near the City of
Almaty in southeastern Kazakhstan. The site is in the steppe zone in
the foothills of the western Tianshan Mountains and ca. 100 km from
the Saryeski-Atyrau Desert to the north. The Tramplin section is
1050 cm thick and 250 samples were taken at intervals of 2–6 cm for
13
C
org
analysis. Ten AMS
14
C dates were obtained from this section
and the result showed that it spanned the period from 46,000 yr BP to
35,000 yr BP.
The δ
13
C
org
values in central Kazakhstan loess-paleosol sequence
spanning the past ca. 46,000 yr varied between -22.1 ‰ and -26.2
‰. The calculated proportion of C
3
plants relative to C
4
plants was ≥
85% in nearly all of the samples, suggesting that C
3
plants dominated
the vegetation during the study period. The abundance of C
4
plants
reached a maximum (ca. 15%) during the last glacial maximum (ca.
25,000 – ca.19,000 yr BP). The
13
C
org
signature was most likely an
indicator of moisture and the moisture variations in central
Kazakhstan were associated with the precipitation in Western
Europe. The
13
C
org
-indicated moisture variations exhibited five
stages: decreasing during stage 1 (ca. 46,000 – ca. 31,500 yr BP),
increasing during stage 2 (ca. 31,500 – ca. 25,500 yr BP), again
decreasing during stage 3 (ca. 25,500 – ca. 19,000 yr BP), fluctuating
along a constant line during stage 4 (ca. 19,000 – ca. 5000 yr BP),
and increasing during stage 5 (last ca. 5000 yr). Our comparison
demonstrated a general similarity between the
13
C
org
-indicated
moisture variations in central Kazakhstan and the reconstructed
precipitation variations in Western Europe. The similarity implies
that the moisture of the past ca. 46,000 years in central Kazakhstan
has been controlled or modulated by westerlies that brought water
vapor from the North Atlantic not only to Western Europe but also to
central Kazakhstan.
Kazakhstan is a bridge through which the eastern civilization
and the western civilizations have interacted and through which the
agricultural cultures and the nomadic cultures have interacted.
Consequently, the Kazakhstan has been rather colorful with
interblended archaeological cultures and thus is an ideal region to
53
search for the footprints of the cultural exchanges between the East
and the West. Numerous studies have confirmed the non-negligible
impact of climate change on the evolution of human culture.
However, this cross study (climate change and cultural evolution) is
not very common in Kazakhstan and the most important reason is the
lack of reliable paleo-climate reconstruction data. Therefore, the
combination of paleo-climatic reconstruction and archaeological
research has great research significance in Kazakhstan.
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