古地貌演化对洛阳盆地新石器中晚期至夏商时期水稻种植的影响

水稻是起源于中国南方长江流域的重要农作物，新石器中期以后传播到北方地区。由于北方较于南方相对干旱，因此对水分条件需求较高的水稻在北方地区的种植往往表现为更强烈的地域选择性。本文选取中原地区地形特征较为复杂的洛阳盆地开展了流域调查和浮选工作，结合前人在本区做的炭化植物遗存研究成果，分析了新石器中晚期至夏商时期洛阳盆地不同地貌部位水稻（Oryza sativa）遗存的分布特征，再根据本区平原区和黄土台塬沟谷区全新世地貌演化的不同特点，探讨了古地貌演化对洛阳盆地史前水稻种植的影响。研究表明，裴李岗文化时期暂未发现水稻遗迹，平原区湖沼遍布，不适宜人类居住，古人可能更倾向于居住在黄土台塬沟谷区的稳定阶地面上；仰韶文化晚期古稻主要分布在黄土台塬沟谷区，与当时沟谷区河流夹积形成的富含粘土的湿润冲积平原有关，而此时平原区距今7000~4000年为稳定干燥的T₁阶地面，更适合发展粟（Setaria italica）作农业；龙山时期没有在沟谷区发现水稻遗存，可能与距今4000年前后沟谷区河流下切侵蚀导致的泛滥平原减少有关，而龙山晚期在伊洛河平原区的遗址发现了古稻遗存，推测与龙山晚期降水增多和洪水频发，出现较多水洼低地有关；二里头时期，古稻在平原区和黄土台塬区都有分布且遗址数量较多，可能与距今4000~3800年龙山晚期古洪水事件后，洪水退去遗留的低洼地有关；二里头和二里岗时期，盆地内古稻遗址普遍增多，平原区古稻遗址可能占更大比重，推测可能与古地貌特征、人类文化自身发展，以及农田管理技术的进步等均有关系。

THE INFLUENCE OF LANDSCAPE EVOLUTION ON RICE PLANTING IN THE MIDDLE-LATE NEOLITHIC PERIOD TO XIA-SHANG DYNASTIES IN LUOYANG BASIN

As an important wet crop originated in the Southern China,rice that cultivated in the relatively dry north display strong geographic selectivity.This study is designed to investigate the the impact of paleogeomorphological evolution on rice cultivation in the prehistoric Luoyang Basin(34°30′~34°50′N,112°17′~112°55′E)with complex topographical features in the Central Plains based on field survey and flotation work.We selected 12 sites in Luoyang basin for sampling and flotation,but rice was only found at Zhaiwan and Zhangcun sites.There are more than 700 grains of ancient rice in the Zhaiwan site(34°33′56″N,112°42′22″E),which have been dated to the late Yangshao Period(5500~5000 a B.P.)according to AMS 14C dating(5163±127 cal.a B.P.).And we found one rice in Zhangcun site(34°34′41″N,112°43′14″E),which have been dated to the late Longshan Period(4500~3900 a B.P.)according to AMS 14C dating(4320±96 cal.a B.P.).On this basis,combined with the previous research results of carbonized plant remains in Luoyang Basin,the distribution characteristics of rice remains in different geomorphologic areas were studied.The results suggest that no trace of rice has been found in the Peiligang Culture period(9000~7000 a B.P.).The plain area was full of lakes and swamps,which were not suitable for human habitation.People probably preferred to live on the stable terrace of the valley area.In the late Yangshao Culture period(5500~5000 a B.P.),rice was mainly grown on the loess terrace valley area,possibly related to the clay-rich wet alluvial plain formed by the rivers at that time;while the contemporary plain area was dry T1 terrace that was more suitable for millet.In the following Longshan period(5000~3900 a B.P.),rice remains was absent in the valley area likely resulted from the reduction of flood plains caused by the erosion of rivers around 4000 a B.P.The appearance of wet lowlands as a result of the precipitation and floods increase during the late years of Longshan(4500~3900 a B.P.)might have been the reason for the rice cultivation in Yiluo River Plains as evidenced by the flotation results.Following that period,the wet lowlands left by the floods in the late Longshan period around 4000~3800 a B.P.might have promoted rice cultivation in the plain area and the loess plateau area as indicated by the high frequency of rice remains recovered from sites in these areas.There was a significant increase in sites with rice remains in the whole basin area during the Erlitou and Erligang periods(3900~2996 a B.P.),while the number of sites in the plain area might overweight that in the valley.This might be caused by both the paleo-geomorphologic factors and the cultural factors including the development of land management techniques.