Late Cenozoic palynological studies on Java
This study is based on palynological investigations at three sites in Java: Bandung Lake, Trinil and Bumiayu. At Bandung Lake (Holocene) three cores were studied, while surface section samples were studied from Trinil in East Java (Middle Pleistocene) and Bumiayu in Central Java (Upper Pliocene). The Trinil site is well known for its hominid fossils.The pollen flora at each site is fully described and illustrated while the pollen record at each location is used to reconstruct their vegetational, environmental and climatic histories. An attempt has also been made to determine whether palynology can be used to assist in dating these deposits. At all three sites, the character of the local vegetation is better reflected than that of the regional vegetation.One of the Bandung sites (Rancaekek) was radiocarbon dated, suggesting deposition between 11,000 and 7,000 yr BP and represents a freshwater lake deposits. The lake gradually shallowed toward 7,000 yr BP, at which time it was drained. The regional pollen component suggests climatic amelioration at about 8,000 yr BP, possibly reflecting the maximum incoming of solar radiation experienced in the Northern Hemisphere about 9,000 yr BP.Studies at Trinil revealed a mosaic of forest and open vegetation growing on a lahar. The former climate at this locality was probably markedly seasonal, not unlike that of the present day. Palynology conclusively demonstrates that this sequence is Pleistocene rather than Pliocene in age. The palynological record at Bumiayu reflects a regressive sequence with lagoonal and freshwater lacustrine environments (Kalibiuk Formation) followed by freshwater fluvial deposition (Kaliglagah Formation). The climate during the deposition of this sequence was markedly seasonal. The data support an Upper Pliocene age for the Bumiayu sequence.Three taxa are shown to have become extinct in Java during the Plio-Pleistocene. These are Stenochlaena lamrifolia and S. areolaris, which become extinct at the end of the Pliocene, and Daczydium, which is thought to have become extinct during the Holocene.