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The effects of global climate change and human activities are anticipated to significantly impact ecosystem services (ESs), particularly in urban agglomerations of arid regions. This paper proposes a framework integrating the dynamic Bayesian network (DBN), system dynamics (SD) model, patch generation land use simulation (PLUS) model, and the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model for predicting land use change and optimizing ESs spatial patterns that is built upon the SSP-RCP scenarios from CMIP6. This framework is applied to the oasis urban agglomeration on the northern slope of the Tianshan Mountains in Xinjiang (UANSTM), China. The findings indicate that both the SD model and PLUS model can accurately forecast the distribution of future land use. The SD model shows a relative error of less than 2.32%, while the PLUS model demonstrates a Kappa coefficient of 0.89. The land use pattern displays obvious spatial heterogeneity under different climate scenarios. The expansion of cultivated land and construction land is the main form of land use change in UANSTM in the future. The DBN model proficiently simulates the interactive relationships between ESs and diverse factors. The classification error rates for net primary productivity (NPP), habitat quality (HQ), water yield (WY), and soil retention (SR) are 20.04%, 3.47%, 4.45%, and 13.42%, respectively. The prediction and diagnosis of DBN determine the optimal ESs development scenario and the optimal ESs region in the study area. It is found that the majority of ESs in UANSTM are predominantly influenced by natural factors with the exception of HQ. The socio-economic development plays a minor role in such urban agglomerations. This study offers significant insights that can contribute to the fields of ecological protection and land use planning in arid urban agglomerations worldwide. • An integrated framework combining DBN, SD, PLUS and InVEST models was proposed. • Impact of natural and socioeconomic factors on ESs was determined under climate scenarios. • The spatial pattern of ESs was optimized and partitioned using DBNs. • ESs in arid oasis urban agglomerations are mainly affected by natural factors. [ABSTRACT FROM AUTHOR]

Abstract: Pastoralists depend on extensive herding to ensure forage availability and pasture sustainability; however, their mobile lifestyles are being challenged by sedentarization policies of the Chinese government. This paper quantifies pastoral migration patterns and their relationships with vegetation dynamics in the Altay and Tianshan Mountains of Xinjiang, China. Using data collected from semi-structured interviews, land use mapping, Geographic Positioning System (GPS) and Normalized Difference Vegetation Index (NDVI) imagery, we show that migration patterns in the two study areas differ regarding distance, elevation change, number of times of migration, and land use. Our analysis reveals that greater migration efforts are largely driven by the shortage of forage in the overwintering villages. The results strongly suggest that current and potential sedentarization policies will compromise the pastoralists' welfare. Therefore, future pastoral policy-making must be built on the long-established relationships between migration patterns and vegetation dynamics. [Copyright &y& Elsevier]

This paper reviews recently published literature, most of which was published in Chinese, and searches for regional patterns of Holocene changes useful in depicting global patterns. The Holocene in the Xinjiang region can be divided into three stages: a warming and dry early stage (from 11 ∼ 10 to 8 ∼ 7 ka BP), a warm and wet middle stage (from 8 ∼ 7 to 4.5 ∼ 3 ka BP) and a fluctuating cool and dry late stage (since 4.5 ∼ 3 ka BP). The Holocene in the northern Tibetan Plateau can also be divided into three stages: a warming and wet stage (from 10.5 ∼ 10 to 5 ∼ 4 ka BP), followed by a variable drying and probably warm stage (5 ∼ 4 to 3 ka BP) and ending with a cool and dry stage (since 3 ka BP). In the Inner Mongolian Plateau, the early Holocene (from 10.5 ∼ 9.5 to 8 ∼ 7.5 ka BP) was warming and dry, and a warm and wet climate occurred from 7.5 to 3.5, during which the best time was 6.3–3.8 ka BP; the climate has been variably drying and probably cooling since 3.5 ka BP. In the northwestern part of the Loess Plateau, several Holocene palaeosols have been identified (10–9, 7.5–5, 4–3 and 2.7–2 ka BP) with the 7.5–5 ka BP palaeosol being most strongly expressed. The best-developed palaeosol-equivalent in major valleys is a swamp-wetland facies deposited between 8885 and 3805 14C yr BP under an extremely wet regime. The climate has fluctuated significantly at least three times around a dry and probably cool regime after the swamp-wetland facies-depositional period. Our summary shows that the Holocene Climatic Optimum occurred nearly contemporaneously (8–5 ka BP) at all sites in the Xinjiang region, in the Inner Mongolian Plateau and in the northwestern part of the Loess Plateau. A warming and wet early Holocene (10–8 ka BP) in the northern Tibetan Plateau is most likely related to high effective soil moisture resulting from snow and ice melting. We propose here that the middle Holocene Climatic Optimum (8–5 ka BP) in arid to semi-arid China was primarily a delayed response of the low latitude oceans to high latitude peak insolation (9–8 ka BP). [ABSTRACT FROM AUTHOR]