Fungal spore record of pastoralism on the NE Qinghai-Tibetan Plateau since the middle Holocene

Pastoralism is considered a crucial factor in the eventual year-round occupation of high-altitude regions (>3000 m asl) of the Qinghai-Tibetan Plateau, and the northeastern Qinghai-Tibetan Plateau (NE-QTP) was an important corridor for early human occupation. We analyzed fossil fungal spore records for the last 8500 years from a high resolution aeolian section at Langgeri (LGR) on the NE-QTP Thirty-two fungal spore types were identified in the LGR section, including seven coprophilous types. We combined analysis of coprophilous fungal spores, Cyperaceae, Artemisia, and Hippophae pollen, and the charcoal >50 mu m fraction to explore the timing and controls of pastoralism on the NE-QTP since the middle Holocene. Pastoralism commenced at LGR shortly before ca. 5.5 ka and gradually increased between ca. 5.5-3.5 ka, but markedly intensified after ca. 2.2 ka, with three periods of growth at ca. 2.1-1.9,1.4-1.2, and 0.6-0 ka, and a decline at ca. 1.1-0.6 ka. The timing of changes in pastoral activity on the NE-QTP based on the coprophilous fungal spore record is supported by regional archeology and historical documents. Technological and political developments, rather than climate change, played key roles in the long-term fluctuations of regional pastoralism on the NE-QTP in the late Holocene.