The temporal and spatial distribution of ancient rice in China and its implications

Abstract

The relics of ancient rice have been regarded as the most important objective evidence of the origination and spread of rice cultivation. Based on the records of 280 rice relics sites and the rice cropping regionalization as well as the distribution map of paddy soils, the current study compiled the temporal and spatial distribution map of ancient rice distribution in China. The map shows that the distribution of ancient rice is spatially extensive and meantime comparatively concentrated, temporarily covering a long and relatively continuous time-span. The rice relics in the Central China double and single rice cropping regions are among the earliest and the most abundant ones, possessing continuity in time sequence. Combined with the discovery of ancient rice and paddy filed relics, soil micromorphology, pollen combination and element geochemistry, it is suggested that Central China was the origin center of rice cultivation in China. Rice had been spread to the rest part of China in three major waves, also to the East Asian part like Korea and Japan. The temporal and spatial distribution of ancient rice reflects the past environmental change, which is also meaningful to the current rice regionalization and planning as well as food security in China.

Quantitative woody cover reconstructions from eastern continental Asia of the last 22 kyr reveal strong regional peculiarities

“…In north-central China (sub-region 2) and the north-eastern margin of the Tibetan Plateau (sub-region 4), the weaker monsoon intensity during the late Holocene reduced annual precipitation (Liu et al, 2014), which could explain the gradual decrease of forest cover in the forest-steppe transition areas. Early agriculture was widespread in the eastern part of the study area during the late Holocene, and deforestation occurred, particularly on the eastern plains (Fu, 2003;Gong et al, 2003Gong et al, , 2007Li et al, 2009;Lu et al, 2009). Many previous studies thus consider that the decline in forest cover during the late Holocene may have been caused predominantly by human activities (e.g.…”

Biogeochemistry of paddy soils

“…However, there is some evidence that the alternating redox conditions may have an effect on mineral weathering and transformation. Once more, paddy soils contain numerous specific minerals such as siderite, jarosite and vivianite (Kyuma, 1978), phyto opal (Gong et al 2007;Wickramasinghe and Rowell, 2006) and different types of green rust (Quantin et al, 2008).…”

“…Paddy soils originating from soils that are high in potassium-bearing minerals are characterized by strong changes in clay minerals due to marked depotassification (Gong, 1983;Gong and Xu, 1990) and the preferred formation of less siliceous, more ferro-magnesian chlorite . In this case, the alternation between reductive and oxidative conditions in paddy soil induces the chloritisation of expanding 2:1 type minerals (Kyuma, 1978).…”

The Human Microbiota as a Marker for Migrations of Individuals and Populations

“…Rice, a crop domesticated ∼10,000 years ago, marked the beginning of agriculture (Gong et al 2007). Its use in agricultural societies selected for higher copy number of the human amylase gene to digest starchy foods (Perry et al 2007).…”