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Impervious surfaces are key indicators for urbanization monitoring and watershed degradation assessment over space and time. However, most empirical studies only extracted impervious surface from spatial, temporal or spectral perspectives, paying less attention to integrating multiple dimensions in acquiring continuous changes in impervious surfaces. In this study, we proposed a neighborhood-based spatio-temporal filter (NSTF) to obtain the continuous change information of impervious surfaces from multi-temporal Landsat images in the Qinhuai River Basin (QRB), Jiangsu, China from 1988–2017, based on the results from semi-automatic decision tree classification. Moreover, we used the expansion intensity index (EII) and the landscape extension index (LEI) to further characterize the spatio-temporal characteristics of impervious surfaces on different spatial scales. The preliminary results showed that the overall accuracies of the final classification were about 95%, with the kappa coefficients ranging between 0.9 and 0.96. The QRB underwent rapid urbanization with the percentage of the impervious surfaces increasing from 2.72% in 1988 to 25.6% in 2017. Since 2006, the center of urbanization expansion was shaped from the urban built-up areas of Nanjing and Jiangning to non-urban built-up areas of the Jiangning, Lishui, and Jurong districts. The edge expansion occupied 73% on average among the different landscape expansion types, greatly beyond outlying (12%) and infilling (15%). The window size in the NSTF has a direct impact on the subsequent analysis. Our research could provide decision-making references for future urban planning and development in the similar basins.

Techniques used to extract shale gas, hydraulic fracturing or fracking, do have draw-backs not least the large consumption of water. We provide the first estimate of water consumption in Chinese shale gas fracking. A case study from Fuling, Chongqing, Southwest China, shows that average water consumption is 27490 m3 per well, much higher (by 29%-160%) than in the USA. Data analysis indicates a significant correlation between water consumption and lateral length of wells (p

Two robust tree-ring width chronologies were developed for the western Tianmu Moun- tains and the Xianyu Mountains of southeast China. Both chronologies were significantly correlated with each other and were arithmetically averaged to build a regional chronology (RC). The RC had significant and positive correlations with winter temperature before the growing season. Based on this relationship, the average temperatures of the previous December to the current March were reconstructed using the RC chronology for the period 1852 to 2006. The temperature reconstruction was significantly correlated with the winter half-year temperature in the eastern Qinling Mountains of central China, 720 km west of the study region, suggesting a large-scale coherence of winter tem- perature variability. The reconstruction corresponds well with an East Asian winter monsoon (EAWM) index in extreme years and reflects the strong influences of the EAWM in this study region. Thus, there is great potential to use tree-ring chronologies to reconstruct past climate change in southeast China, where little dendroclimatic work has been done until now.

We made multi-proxy analysis of 14C, grain size, microfossils, plant seeds, and geochemical elements on samples from a profile in the central West Lake of Lop Nur. The grain size suggests relatively stable sedimentary environment around the Medieval Warm Period (MWP) with weak storm effect, which is followed by frequent strong storm events. Abundant microfossils and plant seeds in this stage indicate a warm and humid fresh to brackish lake environment. C, N, and stable elements are high in content in the sediments while Rb/Sr, Ba/Sr, and Ti/Sr are in a steady low level. In addition, plenty of red willows lived here prior to about 700 a B.P., indicating a favorable environmental condition. The results indicate that the environment in Lop Nur and its west bank turned to be favorable at about 2200 a B.P., where the Loulan Culture began to thrive. Then the climate and environment came to be in the good condition in the Tang and Song Dynasties, when the storm effect became weaker, rainfall increased and the salty lake water turned to be brackish to fresh lake water. Hence, limnic biomass increased with higher species diversity.

Erhai Lake is a large lake with important climatic significance in Yunnan Province, southwest China. The multi-proxy sedimentary records from Erhai Lake indicate the 9 stages of climatic changes with the alternation of warm-dry and cool-wet during the past 8000 a. The variations of Asian monsoon systems were the main cause for the climatic changes in southwest China. The warm-dry period was coincident with the intensification of India monsoon and Northwest Pacific Sub-tropical High Pressure, and the cool-wet corresponding to weak of India monsoon and its main rain belt moving back to southwest China.