The Possible Stimulation of the Mid-Holocene Period’s Initial Hydrological Recession on the Development of Neolithic Cultures along the Margin of the East Asian Summer Monsoon

A better understanding of past East Asian summer monsoonal (EASM) variations, which play a key role in the development of the largely rain-watered agriculture in China, could contribute to better appraising potential impacts on EASM with regard to global climate change. However, our knowledge of the relationship between mid-Holocene hydrological recession and the development of Neolithic culture is limited due to a lack of joint studies and a compilation of spatiotemporal data, especially on the episode of ~6–5 ka from the mid-Holocene Optimum (HO) along the peripheral realm of the EASM. Here, we suggest that the hydrological recession between ~6–5 ka, on the basis of lithology and geochemical element analysis, occurred not only in the Horqin sandy land, but also in other fluvial-lacustrine, stalagmitic, loess, and aeolian records across the whole monsoon-influenced boundary belt. These records indicated varied, more or less synchronous, and coherent moisture changes, yet with not entirely consistent onsets, durations, and degrees. We attributed this spatiotemporal complexity to the orbit-induced weakening of summer solar insolation, and the interactions of the Asian monsoon (AM) and westerlies, as well as topography and regional vegetation factors. Furthermore, the mid-Holocene initial hydroclimatic recession during ~6–5 ka within the thresholds of an eco-environment bearing a capacity system, might have facilitated the development of mid–late Neolithic culture and stimulated the north and northwest expansion and integration of region-specific Neolithic culture.