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Floods are of great concern as the global climate changes, and investigations of flood water infiltration and groundwater recharge are important for water resource management worldwide, especially under conditions of global climate changes. However, information on the relationship between the flood water and groundwater recharge is limited. The objective of this study was to determine the relationship between the flood water depth and the height of groundwater rise using lysimeters and numerical modeling in the floodplain of the Tarim River in northwestern China. The experimental results suggested that the rise in height of the groundwater table was closely related to the flood water ponding depth, and the groundwater depth decreased quickly after flooding due to the high infiltration rate of water originating at the Tarim River. The water table falling velocity was significantly less than the water table rising velocity. If the initial groundwater table was deeper, the variation in the water table rise depth was smaller and the water table falling velocity was slower. The numerical simulation results showed good agreement with the observed data, with a determination coefficient (R2) of 0.87 and a root mean square error (RMSE) of 63.91 cm. A good relationship (R2 = 0.789) between the initial groundwater table depth (H0), initial soil water content (W0), flood water depth (h), and height of the water table rise (H) was established. Considering that natural and artificial flood frequencies are related to flood time interval (dt), a relationship (R2 = 0.892) was developed between them. These results can enhance the understanding of flood recharge characteristics in the floodplains of inland rivers. [ABSTRACT FROM AUTHOR]

The Aksu region within the Tarim Basin is a major source of windblown dust in China due to the arid climate and vast areas under intensive irrigated crop production. Despite the importance of crop production to human subsistence and the local economy, little is known about the amount of soil eroded by wind from agricultural lands in the region. Passive aeolian sediment collectors were used to measure soil loss from an irrigated cotton (Gossypium spp.) field and red date (Ziziphus jujuba Mill.) orchard in the Aksu Oasis during high wind events in 2012 and 2013. Mass of sediment trapped by the collectors was best described as a power function of height above the surface in the cotton field and red date orchard. Soil loss from the cotton field ranged from 0 to 142 g m-2, whereas soil loss from the red date orchard ranged from 0 to 71 g m-2 for single- or multiple-day high wind events. Total soil loss from the cotton field and red date orchard, for the high wind events observed in this study, was 130 and 96 g m-2, respectively, in 2012 and 305 and 165 g m-2, respectively, in 2013. Soil loss was similar to that reported from agricultural lands in other regions of the world. Although soil loss is relatively small compared with the Gobi Desert in China, poor air quality in the Tarim Basin necessitates identifying crop and soil management practices for reducing windblown dust and conserving the soil resource. [ABSTRACT FROM AUTHOR]

Background: China has the biggest population in the world, and has been experiencing the largest migration in history, and its rapid urbanization has profound and lasting impacts on local and national public health. Under these conditions, a systems understanding on the correlation among urbanization, environmental change and public health and to devise solutions at national, local and individual levels are in urgent need.Methods: In this paper, we provide a comprehensive review of recent studies which have examined the relationship between urbanization, urban environmental changes and human health in China. Based on the review, coupled with a systems understanding, we summarize the challenges and opportunities for promoting the health and wellbeing of the whole nation at national, local, and individual levels.Results: Urbanization and urban expansion result in urban environmental changes, as well as residents' lifestyle change, which can lead independently and synergistically to human health problems. China has undergone an epidemiological transition, shifting from infectious to chronic diseases in a much shorter time frame than many other countries. Environmental risk factors, particularly air and water pollution, are a major contributing source of morbidity and mortality in China. Furthermore, aging population, food support system, and disparity of public service between the migrant worker and local residents are important contributions to China's urban health.Conclusions: At the national level, the central government could improve current environmental policies, food safety laws, and make adjustments to the health care system and to demographic policy. At the local level, local government could incorporate healthy life considerations in urban planning procedures, make improvements to the local food supply, and enforce environmental monitoring and management. At the individual level, urban residents can be exposed to education regarding health behaviour choices while being encouraged to take responsibility for their health and to participate in environmental monitoring and management. [ABSTRACT FROM AUTHOR]

The Tarim Basin is an important source of airborne particulate matter that contributes to poor air quality in China. However, little attention has been given to estimating wind erodibility of soils in the region. The objective of this study was to determine the soil wind erodibility for four land use types in the Tarim Basin. Wind erodibility was determined from the dry aggregate size distribution of soils collected from desert, farmland, forest, and shrubland environments in spring 2013. Our analysis revealed that the percentage of soil mass composed of aggregates <840 u,m in diameter (erodible fraction) ranged from 5.2 to 99.9% across sites with a mean of 58.9% across land use types. The four land use types had a high content of erodible aggregates. The mean percentage of soil mass which was comprised of saltation-size (500-100 [im in diameter) and suspension-size material (<100 µm in diameter) was 15.0 and 39.0%, respectively, across land use types. The desert had the highest potential for saltation activity and suspension. Our results suggest that all land use types examined in this study have potential to contribute to the atmospheric dust load in the Tarim Basin and to transcontinental and transoceanic transport of dust. [ABSTRACT FROM AUTHOR]

Hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA) are of increasing concern because of their potential environmental persistence, bioaccumulation and toxicity. Tris-(2,3- dibromopropyl)isocyanurate (TBC) is another brominated flame retardant (BFR) which has recently been found in the environment and begun to attract attention. The objective of this study is to determine the concentration of these three BFRs in surface soil samples collected from a heavily industrialized and urbanized region in East China. Levels of ΣTHBCDs ranged from below detection limits (0.020 ng g-1) to 102.6 ng g-1 on a dry weight basis (dw) with a median level of 15.8 ng g-1 dw. For TBBPA, the concentration ranged from below detection limits (0.025 ng g-1) to 78.6 ng g-1 dw with a median level of 9.17 ng g-1 dw. TBC was found at relatively lower concentrations ranging from below detection limits (0.024 ng g-1) to 16.4 ng g-1 dw with a median level of 0.95 ng g-1 dw. The concentrations of these three BFRs are significantly positively correlated, indicating a common source. Variable BFRs levels were found in different types of soils, with significantly higher concentrations observed at waste dumping sites and industrial areas. The diastereoisomer profiles of HBCDs in most of the soil samples differed from those of the commercial products. The mass inventories of HBCDs, TBBPA and TBC in this region gave preliminarily estimates of 6.68, 2.67 and 0.85 kg, respectively. Therefore, the ubiquitous contamination of soils by these BFRs may well reflect their widespread usage in the study area. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the correlation among urbanisation, climate change and human health. Temporal variation of the prevalence of communicable diseases and the meteorological parameters were analysed, and relations among communicable diseases, meteorological parameters and socio-economic statistical data are discussed based on correlation analysis and stepwise regression. The results showed that both socio-economic development and regional climate change have effects on the prevalence of communicable diseases. Prevalence of blood-borne diseases and sexually transmitted diseases in Xiamen significantly increased during the 1990s. On the other hand, the prevalence of respiratory infectious diseases and gastrointestinal infectious diseases showed a decreasing trend with economic development. Climate has changed in the past 50 years, and particularly so in the last 30 years. The prevalence of gastrointestinal infectious diseases is linked to variation of annual average temperature and relative humidity. Annual average temperature, maximum temperature, minimum temperature and precipitation could be important determinants of the prevalence of insect-borne diseases. [ABSTRACT FROM AUTHOR]

Background: Birth defects are a major cause of infant mortality and disability in many parts of the world. Neural tube defects (NTDs) are one of the most common types of birth defects. In 2001, the Chinese population and family planning commission initiated a national intervention program for the prevention of birth defects. A key step in the program was the introduction of folic acid supplementation. Of interest in the present study was to determine whether folic acid supplementation has the same protective effect on NTDs under various geographical and socioeconomic conditions within the Chinese population and the nature in which the influence of environmental factors varied after folic acid supplementation. Methods: In this study, Heshun was selected as the region of interest as a surrogate for helping to answer some of the questions raised in this study on the impact of the intervention program. Spatial filtering in combination with GIS software was used to detect annual potential clusters from 1998 to 2005 in Heshun, and Kruskal-wallis test and multivariate regression were applied to identify the environmental risk factors for NTDs among various regions. Results: In 1998, a significant (p < 0.100) NTDs cluster was detected in the west of Heshun. After folic acid supplementation, the significant clusters gradually moved from west to east. However, during the study period, most of the clusters appeared in the middle region of Heshun where more than 95 percent of the coal mines of Heshun are located. For the analysis, buffer regions of the coal mine zone were built in a GIS environment. It was found that the correlations between environmental risk factors and NTDs vary among the buffer regions. Conclusion: This suggests that the government needs to adapt the intervention measures according to local conditions. More attention needs to be paid to the poor and to people living in areas near coal mines. [ABSTRACT FROM AUTHOR]

Previous studies on birth defects risk from environmental factors focused on the dose-response relationship of exposure to toxic materials. The purpose of this article is to investigate the relationship between the geological background and occurrence ratio of neural tube defect (NTD) birth defects. Bayesian method was used to adjust the occurrence of NTD birth defects; both parametric and nonparametric statistical methods were used to quantify the correlation between geological background and human birth defects risk. At the two limbs of anticline rock, whose kernel stratum is of Archean kingdom, age of rock strata showed significant positive correlation to the occurrence of birth defects risk. In the region inside 4 km around the fault zone, the occurrence ratio of NTD birth defects is the highest; and decreases when the buffer distance increases. In macro spatial scale, geological background has a significant correlation to the birth defects risk with people residing near the fault zone having higher risk to beget babies with birth defects. [ABSTRACT FROM AUTHOR]