By using detrended fluctuation analysis (DFA), the present paper analyzed the nonlinearity and fractal properties of tree-ring records from two types of trees in northwestern China, and then we disclosed climate change characteristics during the past 500 years in this area. The results indicate that climate change in northwestern China displayed a long-range correlation (LRC), which can exist over time span of 100 years or longer. This conclusion provides a theoretical basis for long-term climate predictions. Combining the DFA results obtained from daily temperatures records at the Xi’an meteorological observation station, which is near the southern peak of the Huashan Mountains, self-similarities widely existed in climate change on monthly, seasonal, annual, and decadal timescales during the past 500 years in northwestern China, and this change was a typical nonlinear process.

This study integrated remote sensing, geographic information system, landscape ecology, and spatial analysis, and is based on meteorological data and four remote sensing images (2000-2015). The aim of this study was to analyse climate trends and spatiotemporal changes in agricultural landscape patterns, and calculate agricultural ecosystem service value (AESV) in Xinjiang, China. In addition, correlation analysis further enabled the quantification of agricultural landscape pattern changes in response to climate change. Results showed that temperature and precipitation registered a fluctuating ascending trend in most areas of Xinjiang. Landscape diversity and fragmentation increased during the same period. AESV showed a trend of gradual increase, the waste disposal and the water retention are the most important ecological functions. Besides, agricultural landscape pattern significantly correlated to climate and the effect of precipitation on agricultural landscape patterns has been greater than the effect of temperature during 2000-2015.