Abstract:

The Liangzhu sites group is located in Yuhang division of Hangzhou city, Zhejiang Province. It is the most representative site of Liangzhu culture (5343 ka BP) by virtue of its site density, diversity and hierarchical differences. Synthetic analyses of grain size and pollen of sedimentary samples from North and West Liangzhu profiles near the Liangzhu citywalls revealed the relationship between the rise and fall of prehistoric cultural and four stages of Holocene sedimentary environment evolution in this area: (1) before 7 ka BP, sedimentary environment went into a relatively high water level stage with cyangray stillwater deposits and the finest grain size (665 Ф). The forest expanded and was characterized by dramatic rise of broadleaved evergreens under a warm and humid climate; (2) 751 ka BP, the regional water level declined and the overlying shallowwater deposits were thin with partial strong hydrodynamic. Human activities began to emerge and intensified in the late period of this stage evidenced by high proportions of Gramineae pollen (Pollen Zone 1); (3) 5143 ka BP, the water level continually declined and reached the lowest level. Liangzhu culture sites distributed all over the lowlying plains with thicker cultural layers. The evergreen broadleaved pollen were dominant taxa with Pinus pollen fluctuating (Pollen Zone 23); (4) 433 ka BP, the level of water increased, and the Liangzhu cultural layers were submerged by river floodplain facies which were mainly made up of brown yellow silt (555 Ф). Along with the impact of human activities, Gramineae pollen decreased clearly during 4336 ka BP (Pollen Zone 4), and then remains high (Pollen Zone 5). Hydrological changes might be the controlling factor of the collapse of the late Neolithic Culture in the Liangzhu sites group.

Key words: environment evolution, Liangzhu Sites Group, grain size, pollen