Landscape transformations of early rice agriculture: methodological developments and new results in the archaeological identification of arable rice systems in prehistory Introduction: Investigating Weeds in the Early Rice Project Our current NERC-funded project aims to reconstruct early arable systems of rice cultivation, and to better establish how ancient arable rice systems be seen using archaeobotanical data. One method is by building modern analogues using the crop weeds found within each type of cultivation regime. Cultivation conditions can be determined by associated weed flora, diatoms and sponge spicules. Our current research programme based on analogue field studies and a database of rice weeds aims to refine methods for identifying the signature of different rice cultivation regimes through weed seed, phytolith and diatom assemblages. Archaeological samples from the Lower Yangtze from between 5000 and 1800 BC provide samples tracking the evolution of weed flora from Pre- Domestication cultivation (for example at Tianluoshan) to later intensive systems. Alison Weisskopf, Dorian Q Fuller, Ling Qin Institute of Archaeology, University College London Rice Cultivation Systems, associated weeds, and phytolith morphotypes from each system Different cultivation systems produce different flora assemblages. Rice weeds and sediment samples have been collected from a variety of arable systems in India, China, Thailand and Laos, seeds added to a reference collection, and husks, leaves and culms processed for phytolith references. The sediments processed to modern analogues of phytolith assemblages for the various field systems. Analogue study sites, crops and wild Crops Wild Table indicating reported presence of weeds (by genus) across 3 cultivation regimes in India and co-occurring with wild rices Rain fed inundated rice, LaosHarvested paddy fields and transplanted rice, Laos Deep water wild rice (Rufipogon) reserve, Laos Harvested upland rice and weeds, Laos Brachiaria husk phytolithsHeliotropium indicumDigitaria adscendans huskCyperus compactus & Mimosa pudica Leersia hexandra leaf Marsilea crenataCyperus pilosus husk, from deep water rice at Pratchnaburi, Thailand Ipomea aquatica Late Majiabang paddy field systems at Chuodun, photo (left), plan (right) Similar Caoxieshan field features sampled April ~ BC Mutlivariates analysis: Canonical Corresponence Analysis of phytolith assemblages Baligang (Yangshao-Longshan ( BC)) Tianluoshan (Hemudu Period ( BC)) Majiabang (Majiabang period BC)) Xiaodouli (Songze Period: BC) Maoshan (Liangzhu Period: BC) Baligang Maoshan Tianluoshan More rice More panicoids More weedy grasses NERC Natural Environment Research Council UCL and PKU Peking University, Zhejiang Institute and Suzhou Museum & Indian Colleagues- Deccan College Pune, Allahabad University, Karnatak University NAFRI in LAOS and The Royal Rice Reserve, Thailand Professor Sato, Chikai Muto Melissa Tan Eleanor Kingwell Banham Professor Kajale Professor Mohanty Emma Harvey Acknowledgements Rain fed, transplanted rice, Western Ghats INDIA, Preliminary Results, modern field analogues, India Lowland, rain fed, Orissa Preliminary results suggest there are differences in the proportions of phytolith morphotypes that make up the modern field samples from India The samples can be grouped by site and to some extent by system – this should become clear when more samples have been analysed Preliminary Results: archaeological samples, China Phytoliths indicate increased weed vs. rice input Includes husk and culm throughout: not a major crop-processing bias Pytoliths indicate increase in weed diversity, especially grasses through time Reduction of sedges through time