Phytolith Evidence for Rice Cultivation during Prehistoric Periods at Baligang Site of Baizhuang, Dengzhou City, Henan Province

Abstract:

Baligang site is located in Baizhuang village of Dengzhou City, Henan Province of central China. This area is located in the northern margin of the northern subtropical zone. Geomorphologically, this area is inside the Nanyang Basin, with elevations generally 100 to 140 m a.s.l. The local river system belongs to the Yangtze drainage to the south. The climate is warm to temperate, with clear seasons. The site was excavated in 1992 and 1994. Sampling was made in October 1994 by the authors. The cultures of the site include (1) Mid-Late Yangshao Culture period (about 6000-4800 BP), and (2) Shijiahe Culture period (4800-4000 BP).Phytolith research at Baligang site was conducted as part of the Baligang archaeological project, directed by ZHANG Jiangkai of Peking University. One of the major issues in the archaeology of Neolithic periods in the Central China is the elucidation of the agricultural economy. This depends on reconstruction of plant exploitation patterns. Since macrobotanical remains are few or even lacking, thus phytolith analysis is considered an important technique for detecting the ancient agriculture. Pollen and phytolith analyses of the 15 samples collected from the site indicate that the paleovegetation was dominated by Castanopsis, Quercus, Salix, Juglans and Pinus, and the paleoclimate was generally warm and wet (subtropical climate), even though there were small climatic fluctuations. In the phytolith assemblages, there are three distinct morpho-types that, when combined together, are diagnostic of cultivated rice (Oryza sativa). The three morpho-types are (a) typical fan-shaped bulliform phytoliths from rice leaf, (b) scooped "bilobates arranged parallel to each other along the veins of leaf, and (c) silicified epidermis from rice glume. All the three-morpho types are found in the site, with the former two being more abundant, and their abundance increases upward from the Yangshao period to the Shijiahe period. This indicates that rice agriculture was practised in a gradually increasing scale from the Yangshao to the Shijiahe period.

Key words:

Baligang site;Yangshao-Shijiahe Culture;phytolith analysis; rice agriculture

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