title: The evolution of crop cultivation and paleoenvironment in the Longji Terraces, southern China: Organic geochemical evidence from paleosols.
abstract: The Longji ancient agricultural terraces in the Longji Mountain area (Guilin, southern China), which still remain in use, are famous for their magnificent terraced landscape with a mix of ecosystem and human inhabitation. Previous research has revealed the genesis and preliminary paleoenvironmental record of the agricultural terraces, but little is known about variations in crop cultivation over time. In this study, organic geochemical analyses and radiocarbon dating of an aggradational cultivated soil from a terrace profile were used to explore crop type variation and relevant paleoenvironmental change during the period of cultivation on the Longji Terraces. Hydroponic farming with rice (C3) planting has been the dominant cultivation mode since the initial construction of the terraces. Warm-dry climate contributed to the growth of drought-tolerant crop (C4) cultivation in the late 15th century. Temperature deterioration during the Little Ice Age had a negative impact on dry and hydroponic farming activities from the late 15th century to the late 19th century, while climate warming after the Little Ice Age promoted the redevelopment of hydroponic farming.
authors.affiliation: College of Resources and Environment, Linyi University, Shuangling Road, Linyi 276000, PR China.
authors.forename: Yongjian
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Institute of Geochemistry, Chinese Academy of Sciences, 99 West Lincheng Road, Guiyang 550081, PR China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, PR China. Electronic address: lishijie@vip.gyig.ac.cn.
authors.forename: Shijie
authors.initials: S
authors.lastname: Li
authors.affiliation: Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, 39 East Beijing Road, Nanjing 210008, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: College of Civil Engineering and Architecture, Guangxi University, 100 East Daxue Road, Nanning 530004, PR China.
authors.forename: Desuo
authors.initials: D
authors.lastname: Cai
authors.affiliation: Guangxi College of Water Resources and Electric Power, 99 Changgang Road, Nanning 530023, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000383:Agriculture; D002681:China; D057231:Climate Change; D018556:Crops, Agricultural; D017753:Ecosystem; D006801:Humans; D012987:Soil
chemical_list: D012987:Soil
keywords: Ancient agricultural terraces; Crop cultivation; Human-environment interaction; Organic geochemistry; Southern China