TY - JOUR
T1 - Environmental variability in northern Tanzania from AD 1000 to 1800, as inferred from diatoms and pollen in Lake Duluti
AU - Öberg, Helena
AU - Norström, Elin
AU - Ryner, Maria Malmström
AU - Holmgren, Karin
AU - Westerberg, Lars-Ove
AU - Risberg, Jan
AU - Eddudóttir, Sigrún Dögg
AU - Andersen, Thorbjørn Joest
AU - Muzuka, Alfred
PY - 2013/3/15
Y1 - 2013/3/15
N2 - Fossil pollen and diatoms have been analyzed in a sediment sequence from a topographically closed crater lake in northern Tanzania (Lake Duluti), with the aim to reconstruct past changes in lake level and vegetation dynamics. The results provide a new paleoenvironmental record from equatorial Africa covering the period c. AD 1000 to AD 1800. Overall, the pollen and diatom records generate comparable stories of dry and wet periods. Dry conditions are inferred at c. AD 1040-1470, c. AD 1510-1640 and c. AD 1650-1670 with the lowest lake levels at c. AD 1260-1290 and AD 1600-1640. Wetter conditions occurred c. AD 1640-1650 and c. AD 1670-1790. The chronology is based on combined analyses of 210Pb activity and AMS 14C on bulk sediment, and a Bayesian model was applied to establish the age-depth relationship. The hydroclimatic record from Lake Duluti shows good correlation with several East African lakes in a centennial time perspective, although comparison of high frequency variability in the region is hampered by dating uncertainties.
AB - Fossil pollen and diatoms have been analyzed in a sediment sequence from a topographically closed crater lake in northern Tanzania (Lake Duluti), with the aim to reconstruct past changes in lake level and vegetation dynamics. The results provide a new paleoenvironmental record from equatorial Africa covering the period c. AD 1000 to AD 1800. Overall, the pollen and diatom records generate comparable stories of dry and wet periods. Dry conditions are inferred at c. AD 1040-1470, c. AD 1510-1640 and c. AD 1650-1670 with the lowest lake levels at c. AD 1260-1290 and AD 1600-1640. Wetter conditions occurred c. AD 1640-1650 and c. AD 1670-1790. The chronology is based on combined analyses of 210Pb activity and AMS 14C on bulk sediment, and a Bayesian model was applied to establish the age-depth relationship. The hydroclimatic record from Lake Duluti shows good correlation with several East African lakes in a centennial time perspective, although comparison of high frequency variability in the region is hampered by dating uncertainties.
U2 - 10.1016/j.palaeo.2013.01.021
DO - 10.1016/j.palaeo.2013.01.021
M3 - Journal article
SN - 0031-0182
VL - 374
SP - 230
EP - 241
JO - Palaeogeography, Palaeoclimatology, Palaeoecology - An International Journal for the Geo-Sciences
JF - Palaeogeography, Palaeoclimatology, Palaeoecology - An International Journal for the Geo-Sciences
ER -