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[Display omitted] • The drought pattern in China is closely related to the basin distribution and multiple teleconnection factors. • The intensity and frequency of drought in China exhibited an increasing trend. • The ENSO-AO had important positive effects in the major basins in China. • Multiple wavelet coherence helps identify the processes controlling drought changes. Due to increasing global warming and the frequent occurrence of severe drought risk in recent decades, many studies have investigated drought in China. However, the spatiotemporal heterogeneities of droughts are complicated, and a comprehensive analysis of the driving forces has not been thoroughly explored. In this paper, we studied the temporal and spatial patterns of drought in China from 1960 to 2018 and disclosed its relationship with multiple teleconnection factors on different time scales. The results show that (1) Drought in China has exhibited a fluctuating increasing trend over the past 59 years, with a standardized precipitation–evapotranspiration index (SPEI) rate of change of –0.12/10 a, and the most severe droughts occurred during 2000–2010. (2) There was a significant abrupt change in China's meteorological droughts induced by climate change around 1997. (3) The trend in China was characterized by drought in spring and autumn and humidification in winter, while the trend in the Southwest River Basin was characterized by drought. (4) A combination of factors can best explain the drought variations from basin to basin, and the El Niño-Southern Oscillation (ENSO)-Arctic Oscillation (AO) was most commonly the best predictor. The use of multiple wavelet coherence helps to identify the dominant drought change processes. [ABSTRACT FROM AUTHOR]

Summary: In this paper, the trends of the annual streamflow and precipitation and cross correlations between them were analyzed in nine large river basins of China during 1956–2005. The results indicate that: (1) the annual mean streamflow decreases in arid and semi-arid regions of north China; however, increasing trends occur in south and Southwest China; (2) the annual streamflow and precipitation exhibit reasonable correlation in nine large river basins except those located in inland areas. The annual streamflow over most areas of China is fed by precipitation; however, the decline in streamflow is faster than the decreases of precipitation since 1970s in the arid and semi-arid regions of north China. The relationship between the annual precipitation and streamflow presents a non-stationary state in north China. This non-stationary relationship is strongly influenced by both human activities and precipitation changes; (3) a significant increase of water use might be the major factor responsible for the steeper decline in streamflow than in precipitation in Haihe River, Yellow River and Songliao River basins in north China. In inland river areas, increase of water use and actual evapotranspiration might result in decline in streamflow although precipitation has an increase tendency. This paper sheds light on the non-stationary relationship between annual precipitation and streamflow and possible underlying causes, which will be helpful for a better understanding of the changes of precipitation and streamflow in China at large scale and in other regions of the world. [Copyright &y& Elsevier]

The assessment of the accessibility for medical resources is of great significance for understanding the distribution characteristics and optimizing the space allocation of medical resources. This paper incorporated the probability statistical data of actual medical treatment choice behavior of residents into the formulation of accessibility. We constructed a health facility accessibility index combined the travel time with waiting time and an improved three-step floating catchment area method to evaluate the accessibility of outpatient and inpatient treatment for residents. Results showed the accessibility of outpatient and inpatient treatment has significant geographical differentiation characteristics and presents a distribution pattern of high in the eastern and central China and low in the western. The outpatient medical service was available for residents, which there are more than 85% of the population having access to medical services within 30min.The accessibility of inpatient treatment presents a radiological distribution model with provincial capital city as the core, in which the spatial allocation of high-quality medical resources is not balanced and the regional difference is obvious. This study demonstrated the geographical differentiation characteristics of spatial distribution for the accessibility of medical resources in China, which can provide targeted proposals according to medical institutions level. • Evaluating the spatial accessibility from outpatient and inpatient medical treatment. • A health facility accessibility index and the improved three-step floating catchment area method were employed. • The policy-oriented matrix of medical services was constructed to provide policy recommendations for the provinces in China. [ABSTRACT FROM AUTHOR]

Abstract: Freshwater is the essential resource element to support and ensure human life and regional sustainable development. On the basis of the concept of ecosystem service footprint proposed by Burkhard, in this paper, we introduce a new methodological approach that addresses the sustainability and capability of regional freshwater provision and consumption, which we have coined freshwater ecosystem service footprint model (FESF model). The FESF model enhances the accuracy of water provision and consumption calculations and reveals a spatial-pattern of freshwater ecosystem service footprint at the watershed scale, overcoming the shortcomings of the traditional water footprint model, which was first introduced by Rees and Wackernagel in 1992. The proposed model is tested in the Beijing–Tianjin–Hebei (BTH) freshwater supply area in China, where water use restrictions are regularly imposed on the population and economic activities. The results of the physical process and theoretical analysis reveal that FESF model is a reliable and helpful model for researchers to understand the regional freshwater situation. The average FESF is 0.94hectare per capita in BTH, with a maximum of 2.52hectare per capita and a minimum of 0.36hectare per capita. Approximately 16.8% of the considered region, primarily parts of the mid-northern region and the surrounding eastern and southern low-lying regions, is under high freshwater resource pressure. In conclusion, this model can be used by researchers and policymakers for promoting sustainable human–ecology interactions. [Copyright &y& Elsevier]

Abstract: China''s floating population is one of the largest migrations in the world. In recent years, great efforts have been made to identify their socio-demographic characteristics. However, the extent of their concern about the local environment has had less attention in the research. In the major migration cities of China, large numbers of migrants have a serious environmental impact on the ecological environment. Their environmental concerns could influence local environment policy design and environment protection implementation. The role that the temporary nature of the floating population plays in their environmental perception is now attracting the attention of local administrations. Based on an investigation conducted in the Shawan River Basin of Shenzhen City, China, this paper studies the floating population''s environmental concerns and possible movement choices, as well as some socio-demographic features. The results show that the percentage of migrants intending to settle in Shenzhen is much larger than previous studies indicated. As concerns local pollution problems, most respondents seem unconcerned and show indifferent attitudes. In particular, migrants ignore the heavy water pollution, which is the most serious pollution in the Basin. People who intend to settle down have more positive opinions on the local environment. The results also indicate that the migrants do not have enough knowledge or environmental awareness and they lack a sense of belonging, which should concern local supervisors and administration. Better education and social activities should be conducted to improve the situation. [Copyright &y& Elsevier]

Abstract: Evapotranspiration is an important flux term in the water cycle that integrates atmospheric demands and surface conditions. Thus, analysis of the temporal variation of reference evapotranspiration (ET0) will help us to understand climate change and its effect on hydrology. In this paper, we present an analysis of the monthly ET0 at 15 stations during 1961–2005 in the Taoer River basin in China, calculated by the FAO Penman–Monteith method. We derived the growing season and annual total ET0 time series and using the Mann–Kendall method, moving t test and Morlet wavelet conducted comprehensive time series analysis to characterize significance test, abrupt change and period in the ET0 data sets. The results present that: (i) in terms of the seasonal cycle, monthly ET0 reaches its peak in May and growing season ET0 accounts for 60.7% of annual total. Long term growing season ET0 fluctuates in accordance with annual ET0, both having turning points in 1982 and 1993; (ii) with respect to the long term persistence, the trends for growing season and annual ET0 show the same spatial patterns: high positive values in the west study area in the upper reach and negative values in the Southeast study area in the lower reach. The spatial distribution of annual tendencies suggests an influence from the altitude and latitude; (iii) for individual station, abrupt changes in annual ET0 are more pronounced than those in growing season ET0. The timings for the abrupt changes in ET0 series at individual stations are consistent with those in regional ET0. Abrupt changes detected in the early 1980s are all increasing changes, while those in earlier 1990 are all decreasing changes; and (iv) based on the Morlet wavelet analysis, there exist significant periods of 1, 3 and 7.3 years in annual ET0 series and significant 1 year period and 7.3 years period in growing season ET0 series. Maximum air temperature, mean air temperature, relative humidity and bright sunshine hours are main climate variables responsible for the periodicity in ET0. [Copyright &y& Elsevier]

[Display omitted] • Accurate assessment of China's ecological environment changes in the past 20 years is important. • We used time-series NDVI data (1998–2018) to evaluate China's ecological environment change. • In one-third of China the ecological environment has improved, and in 10%, the ecological environment has deteriorated. • The Yellow River Basin is an area where the ecological environment has significantly improved. • The main reason for the deterioration in the ecological environment of the eastern coastal areas is urban expansion. The ecological environment is the foundation of human survival and development. China's ecological environment has undergone a historic transition from partial improvement to overall improvement. In this paper, long time series NDVI data (1998–2018) are used to evaluate the ecological environment change and spatiotemporal change that has taken place in China over the last 20 years, at different scales (regional, provincial, county, and grid scales). Combined with typical areas, the causes of ecological environment change are revealed. The results show that in about one-third of China, the ecological environment improved, and in 10%, the ecological environment deteriorated. Ningxia, Shaanxi, Shanxi, Guizhou, and Guangxi are the provinces in which the improvement of the ecological environment is most pronounced. However, the ecological environments with vegetation as the core in Shanghai and Jiangsu Province have deteriorated significantly. The areas with the fastest improvement in their ecological environment are those with precipitation of 200–600 mm. The Yellow River Basin is an area where the ecological environment has significantly improved. Forestry projects and the development of oasis agriculture effectively promote the improvement of the ecological environment. In the past 20 years, the main reason for the degradation of the ecological environment in eastern coastal areas is urban expansion. China should continue to strengthen its overall layout of forestry projects and improve its ecological environment. When planning its ecological construction, China should fully consider the associated physical and geographical conditions, and adjust measures to local conditions accordingly. China should coordinate the relationship between development and protection and avoid the "pie spread" expansion witnessed in eastern coastal areas. [ABSTRACT FROM AUTHOR]

In this paper, future drought characteristics (frequency, duration and intensity) over China are analysed by using four climate models from CMIP6 under the seven SSP-RCP (shared socioeconomic pathway-representative concentration pathway) scenarios (SSP119, SSP126, SSP434, SSP245, SSP460, SSP370, and SSP585) for three defined periods of 2021–2040 (near-term), 2041–2060 (mid-term) and 2081–2100 (long-term). The corresponding four climate models output from CMIP5 are also used to conduct a comparison analysis between CMIP5 and CMIP6 to address the improvements added to CMIP6 in terms of drought identification. The drought characteristics are identified by applying the standardized precipitation-evapotranspiration index (SPEI) at a 12-month timescale and run theory. The results show that CMIP6 has a robust capability to capture historical (1986–2005) drought characteristics. For the future period of 2021–2040, the decrease in precipitation and increase in potential evapotranspiration will lead to continuous dry conditions in the upper and middle Yangtze River basin and eastern Pearl River basin. Relative to the reference period, drought events will be more frequent and severe with longer durations in the Northwest River basins and middle Yangtze River basin. Furthermore, higher emissions signify a greater increase in drought frequency and intensity in the long-term period. Except for the SSP585 scenario, the lower emission scenario corresponds to the higher drought duration soon and in the mid-21st century (2021–2060). This finding is regarded as a "strange phenomenon", which cannot be detected by the previous CMIP5-based emission scenarios (RCP2.6, RCP4.5 and the unlikely pathway RCP8.5). Therefore, additional "possible future"-based scenarios (SSP119, SSP126, SSP434, SSP245, SSP460, and SSP370) should be included in extreme climate studies, especially for the near future and mid-21st century. Notably, compared with CMIP5, the reduced biases in drought characteristics are more likely associated with improvements in the representation of physical processes in climate models from CMIP6. The results of this study could provide a basis for the development of drought adaptation measures over China. • Latest CMIP6 climate models and seven SSP-RCP scenarios are used to analyze the possible changes in droughts over China. • More robust projections will be presented by CMIP6 than CMIP5, due to the better representations in physical processes. • The higher emission signifies shorter drought duration, lower precipitation and PET in mid-21st century over China. [ABSTRACT FROM AUTHOR]

The China Geochemical Baseline (CGB) project (2008–2013) obtained harmonious geochemical baseline data covering all of China, and provided reliable data for 76 elements including F from 3382 top and 3380 deep soil samples. This paper described the statistical and spatial distribution of fluorine (F) throughout China. F concentration ranged from 63 to 9364 μg/g in top soil and ˂ 52 to 9346 μg/g in deep soil. The median concentration of F, which is deemed to be the geochemical baseline in top and deep samples are 488 μg/g and 456 μg/g respectively. The mean concentration of F in top and deep soil samples are 506 μg/g and 482 μg/g respectively. Low F concentrations areas are linearly distributed from northeastern to southwestern China, and high F concentrations areas are distributed in northwestern, northern China and karst area. The anomalous centres of F are exactly correlated with F mineralization. This distribution pattern of F in pedosphere is influenced by minealizations, lithology background, geomorphic landscapes, drainage basins and soil types. Generally, fluorine-bearing rocks provide a reliable source of F in pedosphere, and the geochemical behavior of F determines its ability to migrate in different media. • Low F concentrations areas are linearly distributed from northeastern to southwestern China, and high F concentrations areas are distributed in northwestern, northern China and karst area. • This distribution of F in China's pedosphere is influenced by lithology background mainly. Geomorphic landscapes, drainage basins and soil types played regional-scale roles. [ABSTRACT FROM AUTHOR]

• A physically-based, national-scale hydrological model in China was developed with 19,406 sub-watersheds and 81,687 contour belts. • The research incorporated new mechanisms on soil moisture movement in special vadose zone and strengthened the elevation effect of meteorological and vegetation variables. • The results can achieve a detailed description of the spatio-temporal variation of hydrological variables in large-scale region with diverse climate, topography and underlying surface conditions. Expansion of a detailed hydrological modelling from catchment- to national- or continental-scale is of important theoretical and practical significance, yet faces many challenges. We developed a high-resolution, physically-based hydrological model named WEP-CN (Water and Energy transfer Processes in China) for China. Different climatic and hydrological conditions and geological structures as well as their impact on infiltration and runoff were examined and incorporated in WEP-CN. The study area (9.6 million km2) was divided into 19,406 sub-watersheds and 81,687 contour belts. The computation units, model input, and model structure and parameters in WEP-CN were improved to obtain a well-defined simulation area, a more reliable input as well as a detailed description of soil moisture movement in several special vadose zones such as karst development, swelling and frozen soil. Continuous simulations of various natural hydrological processes were conducted for 62 years from 1956 to 2017. We demonstrated the efficacy of our model by comparing simulated and statistical monthly streamflow at 203 hydrological stations across the country. For the validation period of 1981–2000, the Nash-Sutcliff Efficiency (NSE) was found to be larger than 0.7 at 80% of the stations, and the absolute value of relative error (RE) was less than 10% at 95% of the stations. Our result highlights the benefit of incorporating new mechanisms on the special vadose zone water movement and accounts for the impact of elevation change on meteorological and vegetation variables. This paper can serve as a reference for large-scale hydrological simulation with diverse climate, topography and underlying surface conditions. [ABSTRACT FROM AUTHOR]

• The seasonal cycles of simulated runoff show good agreement with the UNH/GRDC composite runoff. • VIC-CN05.1 generally reproduces the monthly time series of latent heat fluxes well at flux tower sites in China. • The monthly modeled 0–10 cm soil moisture anomalies are highly correlated to in situ measurements. • The spatial patterns of simulated snow variables are generally similar to observations in northeastern and northwestern China. • Except for the northwest basin, the simulated monthly TWSC match well with that from the GRACE. This paper describes a daily 0.25° × 0.25° terrestrial hydrological dataset (VIC-CN05.1) for China during 1961–2017. The dataset is simulated by the latest variable infiltration capacity (VIC) model and driven by pure station-based atmospheric forcings and high-resolution soil parameters based on field surveys. Multiple observational (in situ and remote sensing) products and five statistical metrics, including biases, relative error (RE), root mean square error (RMSE), Nash-Sutcliffe efficiency coefficient (NSE), and correlation coefficient (R), are used to validate the model outputs. The results indicate that the seasonal cycles of simulated total runoff and composite runoff from the University of New Hampshire and Global Runoff Data Centre (UNH/GRDC) show good agreement in the Yangtze, southeast, and Pearl River basins, with positive REs ≤ 7% and NSEs ≥ 0.87. At the Changbaishan, Haibei Shrubland, and Qianyanzhou flux towers, VIC-CN05.1 reproduces the monthly latent heat fluxes well during 2003–2005. The monthly modeled 0–10 cm soil moisture anomalies are highly correlated to in situ measurements (438 stations) during 2003–2016, with mean R = 0.80. The spatial patterns of simulated and observed snow depth, snow water equivalent (SWE), and snow cover in winter are generally consistent in the northeastern and northwestern China. Except for the northwest basin, the simulated monthly terrestrial water storage changes in most river basins (particularly the Yangtze, Huai, and Yellow River basins) match well with observations based on the Gravity Recovery and Climate Experiment (GRACE) during 2003–2016, with positive NSEs and mean R = 0.41. This terrestrial hydrology dataset is valuable for hydroclimatic research in China, such as model evaluations and long-term trend analyses. [ABSTRACT FROM AUTHOR]