Multi-proxy evidence for late-holocene agricultural activities from coastal lagoons on the East Coast of Korea

Abstract

Multi-proxy records of chronologically well-defined sediments have been recently reported from four lagoons (Bongpo marsh, Lake Cheonjinho, Lake Ssangho, and Lake Soonpogaeho) in the Yeongdong region on the east coast of Korea. They deserve close examination as they clearly show the transition towards an agricultural society and local land-use changes during the late Holocene. Bongpo marsh began to develop ca. 650 BC as a coastal lagoon was rapidly filled with organic matter. Rice agriculture intensified sufficiently to cause a noticeable shift in the pollen record from ca. AD 600. An intensification in rice agriculture began from ca. AD 780 at Lake Cheonjinho and from ca. 100 BC at Lake Ssangho. Soonpogae lagoon was almost completely isolated from the sea by sand barriers when human impact intensified about AD 80. Rice agriculture was introduced into Sokcho/Gosung area (Lake Cheonjinho and Bongpo marsh) long after its arrival in the Gangneung/Yangyang area (Lakes Soonpogae and Ssangho), despite the absence of any geomorphic barrier to hinder the spread of rice cultivation along the coast. This finding indicates that it is difficult to identify the arrival date of rice agriculture in a specific area using pollen records since the pollen is generally a better indicator of the beginning of agricultural intensification. The multi-proxy data examined in this paper imply that in order to pinpoint dates of important agricultural events and reconstruct land-use history, it is essential to take a multidisciplinary approach using both palynological and archaeological evidence.