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Drought awareness promotes people to be more sensitive to water shortage and more likely to support water-saving policies. Studying the spatiotemporal patterns and determinants of drought awareness is necessary for developing drought-resistant measures that can adapt to regional social responses. This paper employs the Baidu Index and sc-PDSI, in conjunction with the Principal Component Analysis, to explore the spatiotemporal patterns and influencing factors of drought awareness in China. The results indicate that the first two principal component modes can explain 75% of the total variance of drought awareness in China. The drought awareness of the people is more sensitive to summer droughts and less to winter droughts. The population and education level are the two most important influencing factors at the current stage. It is found that people are most concerned about the drought in Northeast China, while people in central and eastern China are concerned about the drought events in local and other regions. The responses of drought awareness to actual meteorological drought events can be synchronous or asynchronous for different regions. The results demonstrate the usability of big data in drought awareness research and provide crucial insights for the formulation of drought mitigation policies in China. [ABSTRACT FROM AUTHOR]

This paper studies the emissions of SO and COD in China using fine-scale, countylevel data. Using a widely used spatial autocorrelation index, Moran's I statistics, we first estimate the spatial autocorrelations of SO and COD emissions. Distinct patterns of spatial concentration are identified. To investigate the driving forces of emissions, we then use spatial econometric models, including a spatial error model (SEM) and a spatial lag model (SLM), to evaluate the effects of variables that reflect level of economic development, population density, and industrial structure. Our results show that these explanatory variables are highly correlated with the level of SO and COD emissions, though their impacts on SO and COD vary. Compared to ordinary least square regression, the advantages of SLM and SEM are demonstrated as they effectively reveal the existence and significance of spatial dependence. The SEM, in particular, is chosen over the SLM as the role of spatial correlation is stronger in the error model than in the lag model. Based on the research results, we present some preliminary policy recommendations, especially for those high-high cluster regions that face significant environmental degradation and challenge. [ABSTRACT FROM AUTHOR]

China's urban environments are particularly vulnerable to flooding due to climate change and rapid urbanization. Study of the urban flood risk analysis has significantly increased over the past decade, and this paper therefore reviews the main results (i.e. theoretical basis, methods, techniques, case studies) obtained in the literature from China. We focus on the following topics: (1) urban flood hazard analysis, (2) exposure and vulnerability analysis, and (3) urban flood risk assessment. Recent advances made in the research area are presented with suggestions for further research to improve the availability and reliability of urban flood risk analysis. [ABSTRACT FROM AUTHOR]

Climate change will affect the regional ability to achieve the poverty reduction and sustainable development (SD) objectives. Thus, any action plans to achieve these objectives should make climate change policies an integral part of the development planning process. The best practices and measures of climate change policies should be implemented to ensure regional or community sustainability. In this paper, a case study that promotes the integration of carbon sequestration into sustainable forest management and rural development plan with multi-stakeholders participation is introduced. To achieve SD goals, appropriate tools and methods are required to address impacts of alternative forest land uses on carbon sequestration and rural sustainability, and to prioritise land use options. A range of forest land use scenarios that address various aspects of the forest carbon sequestration rate and rural sustainability are evaluated against a SD indicator system. Planting vegetation is one of the practical approaches in mitigating global warming by sequestrating carbon from the atmosphere to plant matter and soil. In order to protect environment, reduce excessive soil erosion, and decrease the propensity and frequency of flooding and other natural disasters, China has initiated nationwide pivotal projects such as 'Grain for Green' to mitigate exacerbated environmental deterioration and degradation. Such ecological programs may affect the socio-economic livelihoods of peasants and the economic activities of the whole region. The impact and economic uncertainty associated with such projects urge policy makers to include all stakeholders in the decision making process so that an agreeable solution towards sustainable rural development can be identified. This study uses Liping County in Guizhou province as a case study to identify a consensus among peasants regarding planting selected tree-species. Analytic hierarchy process (AHP) is used as a multicriteria decision making tool to rank sustainability criteria and determine the priority of options. The method helps policy makers to understand what the peasants want to achieve by participating in a Grain for Green program and what their priorities are with respect to particular types of vegetation. The case study finds that economic and financial concerns are the most important drivers of the decision of which trees to plant among the peasants who took part in the implementation of the Grain for Green program. As a result of this, Gingko, redpine, and Chinese chestnut were the predominant trees planted under the program. The integrated assessment based on the AHP method provides an effective tool to help understand how economic, social and environmental factors are related to each other in affecting the nature of rural sustainability. [ABSTRACT FROM AUTHOR]

Precipitation fluctuations are continuously threatening the environment and may cause huge economic losses. In present study, the precipitation over China has been evaluated under five principal shared socioeconomic pathways (SSPs) scenarios during 2015–2099 based on eight CMIP6 models bias-corrected by the method of Equidistant Cumulative Distribution Functions. The results showed that (1) the simulated precipitation in China was in good agreement with observed precipitation for the eight CMIP6 models during 1961–2014, especially for the UKESM1-0-LL and MIROC6. However, the simulated annual mean precipitation has been significantly overvalued in the Southwest River basin (> 50%), while it was undervalued in the higher elevations of the Northwest River basin (< − 60%); (2) the annual mean precipitation will show a fluctuating upward trend during 2015–2099 over China under all the SSPs scenarios for the eight CMIP6 models. The rate of precipitation increase over north China will be higher than that in south China, especially in the Northwest River basin (reach 57.44% in the 2090s under the SSP5-8.5 for the ensemble mean). This increase of the precipitation in north China might alleviate the shortage of water there, but will not change the pattern of more rain in the south and less in the north; (3) in the southeastern basins, the precipitation of the multi-model ensemble (MME) and MIROC6 during 2011–2020 will be lower than that of 1961–2010 (− 6.53 to − 0.06%) under all SSPs scenarios. While the precipitation will increase obviously under all the SSPs scenarios, especially for the SSP5-8.5 scenario after the year of 2060; (4) the bias of the MME was much lower than that of individual CMIP6 models, and the bias of lower SSPs scenarios will be relatively lower. Generally, uncertainty ranges of precipitation fluctuations in north China (15.31–79.26%) will be higher than those in south China (16.06–7.55%). These findings revealed the projections and uncertainties of CMIP6 precipitation over China, which will be helpful for a better understanding of the future evolution of precipitation in China at large scale and in other regions of the world. [ABSTRACT FROM AUTHOR]

Water and energy circulate between provinces and sectors through products and services. The multi-scale input–output method can quantify the resources embodied in direct consumption, domestic trade and foreign trade and the resources in intermediate input and final consumption. In this study, this method is used to calculate the embodied water intensity and embodied energy intensity at the provincial level in China. The impacts of interprovincial water and energy transfers on provincial water stress were analyzed with reference to their water stress index. The results show that direct consumption is the main component of the embodied water intensity, with an average proportion of 52.21%. However, differences among provinces are significant, ranging from 14.82 to 80.11%. The embodied energy intensity is mainly reflected in domestic imports, with a national average of 61.01%. Domestic exports (3.69 × 1011 m3), urban household consumption (2.01 × 1011 m3), and gross fixed capital formation (1.49 × 1011 m3) share the largest proportion of final consumption, and they are also the main components in the final consumption of energy. Provincial water and energy transfers do not play major roles in relieving water stress in the net inflow areas but increase water stress in the net outflow areas. Provinces with high embodied water intensity and energy-induced water intensity tend to transfer more water to other provinces, while provinces with low intensity receive more supplies from other areas. Therefore, it is important to focus on improving the water use efficiency in provinces with active trade and high water and energy intensities, pay more attention to the demand side and avoid the continuous expansion of indirect consumption due to excessive restrictions on direct consumption. [ABSTRACT FROM AUTHOR]

Only a few recent systematic reviews and meta-analysis studies have quantitatively assessed the effect of short-term exposure to ambient fine particular matter with an aerodynamic diameter of less than 2.5 μm (PM2.5) on respiratory disease (RD) mortality and RD hospital outpatient visits in the Chinese population. A total of 46 articles were selected from Web of Science, PubMed, China National Knowledge Infrastructure and Wanfang databases. Generic inverse variance method was employed to pool individual effect estimates. Pooled estimates represented the increased risk of daily RD mortality and RD outpatient visits per 10 µg/m3 increase in PM2.5 concentrations. Positive associations were identified between short-term PM2.5 exposure and RD in China. The risk of RD mortality and RD outpatient visits increased by 0.48% (95% CI 0.40%, 0.55%) and 0.90% (95% CI 0.62%, 1.18%), respectively, per 10 µg/m3 increase in PM2.5 concentrations. A low increased risk of RD outpatient visits (0.62%, 95% CI 0.57%, 0.66%) was identified at a high level of annual mean PM2.5 concentrations (41.36–110.80 µg/m3) with 1.82% (95% CI 1.72%, 1.92%) at a low level of annual mean PM2.5 concentrations (29.86–40.20 µg/m3) through subgroup analysis. Short-term exposure to PM2.5 was associated with increased risks of RD mortality and RD outpatient visits. The increased risk of RD outpatient visits was pronounced at a low level of annual mean PM2.5 concentrations, but the exact mechanisms of this phenomenon require further investigation. Evidence demonstrated in this study could appeal to Chinese policymakers to improve air quality and alleviate the adverse health impact of PM2.5 pollutions. [ABSTRACT FROM AUTHOR]

Coastal water eutrophication and resource depletion have become serious issues in many coastal regions of the world. Seaweed aquaculture in Chinese coastal waters is a very important industry. This work assessed the major environmental benefits of seaweed cultivation, mapped the spatial distributions of various species and analyzed their environmental impacts during 2015 in China. This study found that seaweed aquaculture had brought in considerable environmental benefits, including the removal of about 75,563 t of nitrogen and 9592 t of phosphate from coastal waters, the sequestration of about 539,555 t of carbon, the absorption of 1,980,167 t of CO2, the release of 1,440,612 t of O2 into coastal waters, and the production of 5809 t of Iodine. In addition, seaweed cultivation saved approximately 29,313 t of chemical fertilizers, 1873 t of pesticide and 62,492 ha of farmland compared with terrestrial vegetable cultivation. These results demonstrate that Chinese seaweed aquaculture has turned the pollutants that cause eutrophication into nutrients, which generates considerable environmental benefits as well as socio-economic values. However, seaweed species, as well as coastal water qualities, vary by regions, spatial management of seaweed farms related to the coastal water quality is necessary. In the eutrophic coastal waters, more seaweed species that are highly capable of removing nitrogen and phosphate should be cultivated. Besides, the potentially negative effects of seaweed farming should also be considered before performing spatial management to ensure the healthy development of seaweed industry. As Chinese seaweed production continues to boom, it is a unique opportunity to strengthen the seaweed industry and to reach a win–win situation that both gains considerable environmental benefits and generates substantial socio-economic returns. This is also a promising way for other coastal developing nations/regions to follow. [ABSTRACT FROM AUTHOR]

Based on the outputs of 27 global climate models (GCMs) from the Coupled Model Inter-comparison Project Phase 5 (CMIP5), projected changes of extreme temperature events have been analyzed over nine river basins in China by the end of the twenty-first century relative to the reference period 1961-1990. The temporal and spatial changes and their projection uncertainty are studied using the extreme temperature indices defined by the Expert Team of Climate Change Detection and Indices (ETCCDI) under two Representative Concentration Pathways (RCPs). The model simulations predict a general increasing (decreasing) trend in warm (cold) extremes over China in the twenty-first century, with more pronounced warming trend under a higher emission scenario. The projected changes in cold and warm extremes exhibit a large difference in spatial patterns. The high-latitude and high-elevation regions of China (e.g., Continental and Southwest basins) are projected to respond more strongly to changes in cold extremes, while eastern and southern China (e.g., Yangtze River and Pearl River basins) tend to be more sensitive to the increases in warm extremes. In general, projected changes in cold indices based on minimum temperature tend to be more pronounced than in warm indices based on maximum temperature. Uncertainty analysis shows a large difference among the 27 GCMs under 2 RCP scenarios, and the uncertainty ranges tend to be larger under a higher emission scenario. Overall, the uncertainties in the emission scenarios are smaller than those from the climate models in the near future period. However, for the long-term climate projections (e.g., by the end of the twenty-first century), the projected difference under various emission scenarios tends to be larger than those by different climate models and hence can be the dominant contributor to the projection uncertainty of temperature indices. [ABSTRACT FROM AUTHOR]

Communities are facing severe water stress due to the rapid development of agriculture and industry, climate change, as well as population growth. Climate variability has a big impact on runoff variation and it is important to understand these hydrological responses. Using a water balance model, monthly discharges of 21 climatically different catchments in China were simulated. Sensitivities of runoff to climate change were investigated by adopting hypothetical climate scenarios. Results indicate that the water balance model performs well for monthly discharge simulations of climatically different catchments with Nash-Sutcliffe coefficients >65 % and relative errors falling in the range of ±5 %. In general, runoff in arid north China are more sensitive to climate change than those in humid south China. A 1 °C rise in temperature would probably lead to 1.2-4.4 % decreases in runoff. A decrease in precipitation of 10 % would result in 9.4-17.4 % of decreases in runoff. It is essential to consider the implications of climate change in future water resources management. [ABSTRACT FROM AUTHOR]

Thyroid cancer (TC) incidence has significantly increased worldwide in recent decades, with large differences between urban and rural areas. However, studies on Chinese TC incidence are limited. Research on the relationship between TC incidence and industry activities is also rare. In this work, data from 31 cancer registry cities in China between 2005 and 2009 were used to reveal the trend of TC incidence, compare the incidence among different cities, and analyze the relationship of TC incidence with socioeconomic factors. During the five-year period, TC incidence in China increased by 49.5 % from 3.21/100,000 to 4.80/100,000, with a female-male ratio of 3 and an urban-rural ratio of 2.5. The increase of TC incidence in more developed cities was significant, but it was not in less developed cities. People living in cities with higher secondary industry output had a higher risk of developing TC. The government and scientific community should pay sufficient attention to the rapidly increasing incidence of TC and to industry activities. [ABSTRACT FROM AUTHOR]

Water resources and soil erosion are the most important environmental concerns in the Yangtze River basin, where soil erosion and sediment yield are closely related to rainfall erosivity. The present study explores the spatial and temporal changing patterns of the rainfall erosivity in the Yangtze River basin of China during 1960-2005 at annual, seasonal and monthly scales. The Mann-Kendall test is employed to detect the trends during 1960-2005, and the T test is applied to investigate possible changes between 1991-2005 and 1960-1990. Meanwhile the Rescaled Range Analysis is used for exploring future trend of rainfall erosivity. Moreover the continuous wavelet transform technique is using studying the periodicity of the rainfall erosivity. The results show that: (1) The Yangtze River basin is an area characterized by uneven spatial distribution of rainfall erosivity in China, with the annual average rainfall erosivity range from 131.21 to 16842 MJ mm ha h. (2) Although the directions of trends in annual rainfall erosivity at most stations are upward, only 22 stations have significant trends at the 90 % confidence level, and these stations are mainly located in the Jinshajiang River basin and Boyang Lake basin. Winter and summer are the seasons showing strong upward trends. For the monthly series, significant increasing trends are mainly found during January, June and July. (3) Generally speaking, the results detected by the T test are quite consistent with those detected by the Mann-Kendall test. (4) The rainfall erosivity of Yangtze River basin during winter and summer will maintain a detected significant increasing trend in the near future, which may bring greater risks to soil erosion. (5) The annual and seasonal erosivity of Yangtze River basin all have one significant periodicity of 2-4 years. [ABSTRACT FROM AUTHOR]

A total of thirty-three surface water samples were collected from Meiliang Bay, Gonghu Bay and Xukou Bay of Lake Taihu, and analyzed for synthetic musks, including 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-[γ]-2-benzopyrane (HHCB), 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), 1- tert-butyl-3,5-dimethyl-2,5-dinitro-4-acetylbenzene (MK) and 1- tert-butyl-3,5-dimethyl-2,4,6-trinitrobenzene (MX). Ecological risks of these compounds were characterized by hazard quotient (HQ) method due to a lack of sufficient available toxicity data of synthetic musks. HHCB was the main synthetic musk detected in Lake Taihu, followed by AHTN, MK, and MX. The risk assessment results indicate that low ecological risks were posed by HHCB and total synthetic musks, and even lower risks posed by other synthetic musks in the worst case; much lower ecological risks were caused by both individual and total synthetic musks in the general case. The combined ecological risk from total synthetic musks calculation suggests that the combined ecological risk from all four synthetic musks was expected to be slightly higher than for the individual musks due to their joint action. The HQ spatial distribution maps show that several hot-spot areas were mainly around the river inlets to Lake Taihu, indicating that synthetic musks may be transported to Lake Taihu with municipal sewage and industrial wastewater from surrounding areas. However, the ecological risks in hot-spot areas posed by individual and total synthetic musks were still acceptable. [ABSTRACT FROM AUTHOR]

Spatial and temporal characteristics of actual evapotranspiration over the Haihe River basin in China during 1960-2002 are estimated using the complementary relationship and the Thornthwaite water balance (WB) approaches. Firstly, the long-term water balance equation is used to validate and select the most suitable long-term average annual actual evapotranspiration equations for nine subbasins. Then, the most suitable method, the Pike equation, is used to calibrate parameters of the complementary relationship models and the WB model at each station. The results show that the advection aridity (AA) model more closely estimates actual evapotranspiration than does the Granger and Gray (GG) model especially considering the annual and summer evapotranspiration when compared with the WB model estimates. The results from the AA model and the WB model are then used to analyze spatial and temporal changing characteristics of the actual evapotranspiration over the basin. The analysis shows that the annual actual evapotranspirations during 1960-2002 exhibit similar decreasing trends in most parts of the Haihe River basin for the AA and WB models. Decreasing trends in annual precipitation and potential evapotranspiration, which directly affect water supply and the energy available for actual evapotranspiration respectively, jointly lead to the decrease in actual evapotranspiration in the basin. A weakening of the water cycle seems to have appeared, and as a consequence, the water supply capacity has been on the decrease, aggravating water shortage and restricting sustainable social and economic development in the region. [ABSTRACT FROM AUTHOR]

The present study explores the spatial and temporal changing patterns of the precipitation in the Haihe River basin of North China during 1957-2007 at annual, seasonal and monthly scales. The Mann-Kendall and Sen's T tests are employed to detect the trends, and the segmented regression is applied to investigate possible change points. Meanwhile, Sen's slope estimator is computed to represent the magnitudes of the temporal trends. The regional precipitation trends are also discussed based on the regional index series of four sub-basins in the basin. Serial correlation of the precipitation series is checked prior to the application of the statistical test to ensure the validity of trend detection. Moreover, moisture flux variations based on the NCEP/NCAR reanalysis dataset are investigated to further reveal the possible causes behind the changes in precipitation. The results show that: (1) Although the directions of annual precipitation trends at all stations are downward, only seven stations have significant trends at the 90% confidence level, and these stations are mainly located in the western and southeastern Haihe River basin. (2) Summer is the only season showing a strong downward trend. For the monthly series, significant decreasing trends are mainly found during July, August and November, while significant increasing trends are mostly observed during May and December. In comparison with the annual series, more intensive changes can be found in the monthly series, which may indicate a shift in the precipitation regime. (3) Most shifts from increasing trends to decreasing trends occurred in May-June, July, August and December series, while opposed shifts mainly occurred in November. Summer is the only season displaying strong shift trends and the change points mostly emerged during the late 1970s to early 1980s. (4) An obvious decrease in moisture flux is observed after 1980 in comparison with the observations before 1980. The results of similar changing patterns between monthly moisture budget and precipitation confirmed that large-scale atmospheric circulation may be responsible for the shift in the annual cycle of precipitation in the Haihe River basin. These findings are expected to contribute to providing more accurate results of regional changing precipitation patterns and understanding the underlying linkages between climate change and alterations of hydrological cycles in the Haihe River basin. [ABSTRACT FROM AUTHOR]

In this study, the applicability of the statistical downscaling model (SDSM) in downscaling precipitation in the Yangtze River basin, China was investigated. The investigation includes the calibration of the SDSM model by using large-scale atmospheric variables encompassing NCEP/NCAR reanalysis data, the validation of the model using independent period of the NCEP/NCAR reanalysis data and the general circulation model (GCM) outputs of scenarios A2 and B2 of the HadCM3 model, and the prediction of the future regional precipitation scenarios. Selected as climate variables for downscaling were measured daily precipitation data (1961-2000) from 136 weather stations in the Yangtze River basin. The results showed that: (1) there existed good relationship between the observed and simulated precipitation during the calibration period of 1961-1990 as well as the validation period of 1991-2000. And the results of simulated monthly and seasonal precipitation were better than that of daily. The average R values between the simulated and observed monthly and seasonal precipitation for the validation period were 0.78 and 0.91 respectively for the whole basin, which showed that the SDSM had a good applicability on simulating precipitation in the Yangtze River basin. (2) Under both scenarios A2 and B2, during the prediction period of 2010-2099, the change of annual mean precipitation in the Yangtze River basin would present a trend of deficit precipitation in 2020s; insignificant changes in the 2050s; and a surplus of precipitation in the 2080s as compared to the mean values of the base period. The annual mean precipitation would increase by about 15.29% under scenario A2 and increase by about 5.33% under scenario B2 in the 2080s. The winter and autumn might be the more distinct seasons with more predicted changes of precipitation than in other seasons. And (3) there would be distinctive spatial distribution differences for the change of annual mean precipitation in the river basin, but the most of Yangtze River basin would be dominated by the increasing trend. [ABSTRACT FROM AUTHOR]

Based on daily meteorological data at 43 gauging stations in the Pearl River basin and 65 gauging stations in the Yellow River basin, we analyze changing properties of actual evapotranspiration (ET), reference evapotranspiration (ET) and precipitation in these two river basins. In our study, Pearl River basin is taken as the 'energy-limited' system and the Yellow River basin as the 'water-limited' system. The results indicate decreasing ET in the Pearl River and Yellow River basin. However, different changing properties are detected for ET when compared to ET. The middle and upper Yellow River basin are characterized by increasing ET values, whereas the Pearl River basin is dominated by decreasing ET values. This result demonstrates enhancing drying force in the Yellow River basin. ET depends mainly on the changes of precipitation amount in the Yellow River basin. In the Pearl River basin, however, ET changes are similar to those of ET, i.e. both are in decreasing trend and which may imply weakening hydrological cycle in the Pearl River basin. Different influencing factors are identified behind the ET and ET in the Pearl River and Yellow River basin: In the Pearl River basin, intensifying urbanization and increasing aerosol may contribute much to the evapotranspiration changes. Variations of precipitation amount may largely impact the spatial and temporal patterns of ET in the Yellow River basin. The current study is practically and scientifically significant for regional assessment of water resource in the arid and humid regions of China under the changing climate. [ABSTRACT FROM AUTHOR]

We analyzed seasonal and annual variations of the whole layer atmospheric moisture budget and precipitation during 1961–2005 and their associations with large-scale circulation in the Yangtze River basin, China. The results indicated increasing moisture budget in summer and winter, but decreasing moisture budget in spring and autumn. Positive correlations between moisture budget and precipitation illustrate tremendous impacts the moisture budget has on the precipitation changes across the Yangtze River basin. In terms of seasonal variations, significant correlations were observed between precipitation and moisture budget in spring and autumn in the upper Yangtze River basin. Besides, we also analyzed changes of geopotential height. The positive trends of the geopotential height (850 hPa) were observed in the East Asia and the negative trends in the middle and west Pacific Ocean, indicating increasing geopotential height from south to north in east Asia which largely limited the moisture propagation to north China. While decreasing meridional geopotential height from west to east along the Yangtze River basin caused more moisture propagation from the west to the east parts of the study region, which may benefit more precipitation in the middle and lower Yangtze River basin. [ABSTRACT FROM AUTHOR]