Rice fields and modes of rice cultivation between 5000 and 2500 BC in east China

Recently, rice fields dated between 5000 and 2500 BC were found at the Tianluoshan sit in east China. The early rice fields dated between 5000 and 4500 BC are the oldest rice fields known. The discovery has provided data of recovering reclamation, cultivation, and the ecological system of rice fields in the Neolithic age. People opened up marshes of dense reeds with fire and wooden or bone spades, in order to create rice fields. In the rice fields, there was not only rice, but a lot of weeds as well. The excavations proved that little or even no weeding or irrigation was adopted. However, tilling soil by wooden and bone tools was evidenced. The average yields are estimated to have been about 830 kg for the early period and 950 kg per hectare for the later period. The cultivation system was low-level. Although the Tianluoshan people cultivated rice, they still obtained a great deal of food by gathering and hunting. (C) 2009 Elsevier Ltd. All rights reserved.