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A high‐resolution study of bulk properties in a peat sequence from the Xinjiang Altai Mountains of northwestern China has allowed reconstruction of local variations in peat properties and peat C and N accumulation rates (CAR and NAR) during the Holocene. Analyses of peat bulk density, loss on ignition, and concentrations of total organic carbon (TOC) and total nitrogen (TN) and their elemental ratios and stable isotopic values suggest that changes in peat‐forming vegetation types during different parts of this epoch are the major factors responsible for the variations of peat properties in this sequence. The long‐term peat CAR has been 25.4 ± 7.7 (SD) g C/m2/yr, with lower values during the early Holocene and higher accumulations during the late Holocene, which is opposite to the Holocene variations in CAR in other northern peatlands. In contrast, the long‐term peat NAR is 1.5 ± 0.5 (SD) g N/m2/yr and is higher during the early and middle Holocene and lower during the late Holocene as in other northern peatlands. However, unlike other northern peatlands, long‐term peat NAR does not vary with the CAR, which is influenced by the peat density and accumulation rate. Variations in long‐term peat C and N accumulations in the Altai Mountains can be attributed to changes in primary productivity, in the dominant plant types and in peat decomposition caused by changes in both regional Holocene climate and local conditions. Plain Language Summary: Variations in Holocene carbon and nitrogen accumulations in a peat sequence in the Altai Mountains of northwestern China can be attributed to changes in plant productivity, in the dominant plant types and in peat decomposition caused by changes in both regional climate and site‐specific environmental conditions. Key Points: A high‐resolution study was conducted of bulk properties in a peat sequence from the Xinjiang Altai Mountains of northwest ChinaReconstructions of Holocene peat C and N accumulations in the Altai Mountains of northwest China were doneRegional comparisons imply that plant communities and productivities are major controls on peat C and N accumulation in northwest China [ABSTRACT FROM AUTHOR]

A high-resolution peat humification record is obtained from Hani peatland, northeastern China to study climate change. An absorbance value time series from alkali-extraction is used as a peat humification indicator. In addition, Hani peat magnetic susceptibility and trace elements have also been investigated. There is a sensitive response to abrupt climate changes when comparing a high-resolution peat humification record with a Hani δ18O temperature proxy record and a drift ice record from the North Atlantic Ocean. Based on analyses of factors that affect peat decomposition, we suggest similar paleoclimate significance between the Hani and Dajiuhu peat on the degree of humification with a higher peat humification indicating colder and drier climate conditions. In contrast, a warm and moist climate provides a deoxidized condition that results in lower peat humification. Moreover, the Rb/Sr ratios and χlf in Hani peatland also indicate different climate conditions, especially in late Holocene. According to the Hani peat data, regional paleoclimate variations can be divided into the following five phases: 11.5-10.0 cal. kyr BP with warm climate conditions; 10.0-8.8 cal. kyr BP with sharply cooling and warming climate conditions; 8.8-4.8 cal. kyr BP with alternating cooling and warming climate conditions; 4.8-1.6 cal. kyr BP with warm climate conditions overall and 1.6-0 cal. kyr BP with cold climate conditions. [ABSTRACT FROM AUTHOR]