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Concept: Regions of China

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Sichuan Basin, located in southwest China, has been ranked as the fourth of heavily air polluted regions in China partly due to its deep mountain-basin topography. However, spatial-temporal distribution of air pollution over the basin is still unclear due to the lack of monitoring data and poor knowledge. Since January 2015, six criteria air pollutants began to be monitored in 20 cities across the basin. The measured data enable us to analyze the basin-wide spatial-temporal distribution characteristics of these air pollutants. Results revealed heavy air pollution in the bottom zone, medium in the slope zone, and light pollution in the edge zone of the Basin in terms of the altitudes of air quality monitoring stations across the Basin. The average concentrations of PM2.5 and PM10 were 55.87μg/m(3) and 86.49μg/m(3) in the bottom, 33.76μg/m(3) and 63.33μg/m(3) in the slope, and 19.71μg/m(3) and 35.06μg/m(3) in the edge, respectively. In the bottom and slope of the basin, high PM2.5 concentration events occurred most frequently in winter. While in summer, ozone became primary pollutant. Among the six air pollutants, concentrations of PM2.5 and PM10 decrease dramatically with increasing altitude which was fitted by a nonlinear relationship between particulate matter (PM) concentrations and altitude. This relationship was validated by extinction coefficient profiles from CALIPSO observations and EV-lidar data, and hence used to reflect vertical distribution of air PM concentrations. It has been found that the thickness of higher PM concentrations is less than 500m in the basin. In the bottom of the basin, PM concentrations exhibited stronger horizontal homogeneities as compared with those in the North China Plain and Yangtze River Delta. However, gaseous pollutants seemed not to show clear relationships between their concentrations and altitudes in the basin. Their horizontal homogeneities were less significant compared to PM.

Concepts: Regions of China, Air Quality Index, Yangtze River, United States Environmental Protection Agency, Particulate, Smog, Pollution, Air pollution

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There is considerable uncertainty concerning changes in plant diversity of Chinese secondary forests, particularly with respect to diversity recovery following anthropogenic disturbance. Here we present a meta-analysis of the recovery of woody plant species richness in secondary forests in China, with nearby primary forests as a reference. A total of 125 pairs of secondary-primary forest data reported in 55 publications were identified across China. We analyzed the data by region and logging history to examine their influences on secondary forest recovery. Our results indicated that the woody plant richness of secondary forests in China was close to fully recovered when compared to the primary forest, with the recovery ratio being 85-103%. Higher recovery ratios were observed in central, northeast and southwest China, with lower recovery ratios seen in east, south and northwest China, and the recovery in central China significantly reached the primary forests (reference) level. Concerning logging histories, the recovery ratios showed two peak values, with one at 21-40 years after clear cutting and the other at 61-80 years. We reveal the fundamental recovery patterns of woody plant species richness in secondary forests in China. These patterns provide information for the sustainable management of secondary forest resources.

Concepts: Ecosystem, Sustainability, Tropical rainforest, Plant, Regions of China, Forest, Secondary forest

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Reliable national estimates of CH4 emissions from natural wetlands depend on model validation based on site observations. We therefore evaluated the performance of the CH4MODwetland model in simulating CH4 emissions from 11 representative wetland sites in five regions of China. Model performance analysis showed that this method effectively simulates differences in the CH4 fluxes between different sites and regions. The model efficiency for estimating the daily CH4 fluxes in the northeastern China (NE), Inner Mongolia and northwestern China (NW), the North China plain and the Middle-Lower Yangtze Plain (E) and the Qinghai Tibetan Plateau (SW) was 0.51, 0.20, 0.52 and 0.65, respectively. The efficiency for estimating the annual mean CH4 fluxes in southern China (S) was 0.99. Systematic negative deviation between the simulated and observed CH4 emissions existed in all regions, especially in the NW region, which had a mean deviation (RMD) value of -36.7%. On the national scale, the root mean square error (RMSE), the RMD, the model efficiency (EF) between the simulated and observed seasonal values were 28.7%, -7.8% and 0.93, respectively. The CH4 emissions showed the highest sensitivity to air temperature in the NE and SW regions, and to water table depth in the E region. Based on the sensitivity analysis, future climate warming and wetting are likely to increase the wetland CH4 emissions at different levels in all regions of China.

Concepts: Root mean square deviation, Absolute deviation, China, North China, Mean squared error, Standard deviation, Root mean square, Regions of China

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Previous surveys of neonatal medicine in China have not collected comprehensive information on workforce, investment, health care practice, and disease expenditure. The goal of the present study was to develop a national database of neonatal care units and compare present outcomes data in conjunction with health care practices and costs. We summarized the above components by extracting data from the databases of the national key clinical subspecialty proposals issued by national health authority in China, as well as publicly accessible databases. Sixty-one newborn clinical units from provincial or ministerial hospitals at the highest level within local areas in mainland China, were included for the study. Data were gathered for three consecutive years (2008-2010) in 28 of 31 provincial districts in mainland China. Of the 61 newborn units in 2010, there were 4,948 beds (median = 62 [IQR 43-110]), 1,369 physicians (median = 22 [IQR 15-29]), 3,443 nurses (median = 52 [IQR 33-81]), and 170,159 inpatient discharges (median = 2,612 [IQR 1,436-3,804]). During 2008-2010, the median yearly investment for a single newborn unit was US$344,700 (IQR 166,100-585,800), median length of hospital stay for overall inpatient newborns 9.5 (IQR 8.2-10.8) days, median inpatient antimicrobial drug use rate 68.7% (IQR 49.8-87.0), and median nosocomial infection rate 3.2% (IQR1.7-5.4). For the common newborn diseases of pneumonia, sepsis, respiratory distress syndrome, and very low birth weight (<1,500 grams) infants, their lengths of hospital stay, daily costs, hospital costs, ratios of hospital cost to per-capita disposable income, and ratios of hospital cost to per-capita health expenditure, were all significantly different across regions (North China, Northeast China, East China, South Central China, Southwest China, and Northwest China). The survival rate of extremely low birth weight (ELBW) infants (Birth weight <1,000 grams) was 76.0% during 2008-2010 in the five hospitals where each unit had more than 20 admissions of ELBW infants in 2010; and the median hospital cost for a single hospital stay in ELBW infants was US$8,613 (IQR 8,153-9,216), which was 3.0 times (IQR 2.0-3.2) the average per-capita disposable income, or 63 times (IQR 40.3-72.1) the average per-capita health expenditure of local urban residents in 2011. Our national database provides baseline data on the status of advanced neonatal medicine in China, gathering valuable information for quality improvement, decision making, longitudinal studies and horizontal comparisons.

Concepts: Acute respiratory distress syndrome, Childbirth, Health insurance, Health care, Infant, Medicine, Regions of China, Pediatrics

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Uncovering magnitude, trend, and spatial pattern of land cover/land use changes (LCLUC) is crucial for understanding mechanisms of LCLUC and assisting land use planning and conservation. China has been undergoing unprecedented economic growth, massive rural-to-urban migration, and large-scale policy-driven ecological restoration, and therefore encountering enormous LCLUC in recent decades. However, comprehensive understandings of spatiotemporal LCLUC dynamics and underlying mechanisms are still lacking. Based on classification of annual LCLU maps from MODIS satellite imagery, we proposed a land change detection method to capture significant land change hotspots over Northern China during 2001-2013, and further analyzed temporal trends and spatial patterns of LCLUC. We found rapid decline of agricultural land near urban was predominantly caused by urban expansion. The process was especially strong in North China Plain with 14,057 km(2) of urban gain and -21,017 km(2) of agricultural land loss. To offset the loss of agricultural land, Northeast China Plain and Xinjiang were reclaimed. Substantial recovery of forests (49,908 km(2)) and closed shrubland (60,854 km(2)) occurred in mountainous regions due to abandoned infertile farmland, secondary succession, and governmental conservation policies. The spatial patterns and trends of LCLUC in Northern China provide information to support effective environmental policies towards sustainable development.

Concepts: North China Plain, Mountain, Land use, Urbanization, Northeast China, Regions of China, Sustainability, North China

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Land use change can greatly alter spatial pattern and overall ecosystem service values (ESV). The goal of this study was to explore the likely effects of land use change on ESV in China. In this paper, the spatially explicit land use changes across China from 2010 to 2020 under the 2000s trend scenario and the planning scenario were projected using the Dyna-CLUE model. The ESV evaluation method was improved by adjusting the ESV coefficients using biomass data to reduce the generalization error of proxy-based method. The results revealed that between 2010 and 2020, total ESV increased by 1798 and 2215 billion RMB a(-1) under the 2000s trend scenario and the planning scenario, respectively. The spatial pattern of ESV in 2010 and 2020 presented a logical geographic distribution. The areas with ESV of 50,000 RMB ha(-1) a(-1) and higher occurred primarily in northeastern and southern China, while the areas with ESV of 5000 RMB ha(-1) a(-1) and lower were mainly located in northwestern China. The spatial differences between the two scenarios were insignificant except that the increase of ESV in southwestern China was more prominent in the planning scenario than that in the 2000s trend scenario, while the total ESV in 2020 under the planning scenario was larger than that in the 2000s trend scenario. The increase of ESV occurred mainly in northeastern, southern, and southeastern China due to forest growth and woodland expansion in 2020 compared with 2010. The results of this study can provide useful information for the public and land managers to consider.

Concepts: Systems ecology, Ecological economics, Ecosystem services, Project management, Ecosystem, Ecology, Regions of China, Biodiversity

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The epidemic of HIV-1 CRF01_AE in China was driven by multiple lineages of HIV-1 viruses introduced in the 1990s and increasing, it’s important to investigate the epidemic status of them in china. In this study, we download all available CRF01_AE sequences (n=2931) from China and their associated epidemiological information in the Los Alamos HIV database for our analysis to explore their epidemic status in China. The results showed there were 11 distinct clusters of CRF01_AE strains in China, four major clusters which accounted for 80.0% (1793/2241) of Chinese CRF01_AE strains in total had led a real epidemic. Cluster 1 and 2 were epidemic among heterosexuals and IDUs in southern and southwestern China, while cluster 3 and 4 were predominant among homosexuals in eastern and central China and northeastern China, respectively. HIV-1 CRF01_AE strains detected in heterosexuals had the most complex characteristic, underscoring its important role in the occurrence of multiple CRF01_AE lineages. Furthermore, epidemic history reconstruction analysis using the birth-death SIR package revealed that the four clusters had gone through varying epidemic stages. Cluster 2 and 3 were near the peak of the local epidemic, while cluster 1 and 4 were just in the very early stage of their epidemic. The epidemic status of CRF01_AE clusters in the future are mainly determined by the effect of prevention and control. Our study provides new insights into the understanding of the epidemic dynamic of CRF01_AE in China.

Concepts: Homosexuality, Complex number, Stage, Los Alamos National Laboratory, HIV, Introduction, Regions of China, Epidemic

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Unlike most areas of China, HIV transmission via men who have sex with men (MSM) is increasing rapidly, and has become the main route of HIV transmission in Harbin city. The purpose of the current study was to elaborate the molecular epidemiologic characteristics of the new HIV epidemic. Eighty-one HIV-1 gag gene sequences (HXB2:806-1861) from local HIV infections were isolated; CRF01_AE predominated among HIV infections (71.6%), followed by subtype B (16.5%), CRF07_BC (6.2%), and unique recombinant strains (URFs; 6.2%). URFs were most often identified in the MSM population, which consisted of a recombination of CRF01_AE with subtype B or CRF07_BC. Six clusters were formed in this analysis; clusters I and II mainly circulated in southwest China. Clusters III and IV mainly circulated in southwest, southeast, and central China. Clusters V and VI mainly circulated in north and northeast China. Clusters III and IV may facilitate the transmission of the CRF01_AE strain from the southwest to the north and northeast regions of China. HIV subtypes are becoming diverse with the persistent epidemic in this geographic region. In brief, our results indicate that the molecular epidemiology of HIV is trending to be more complex. Thus, timely molecular epidemiologic supervision of HIV is necessary, especially for the MSM population. This article is protected by copyright. All rights reserved.

Concepts: Disease, Northeast China, Harbin, Subtypes of HIV, Regions of China, HIV, Epidemiology, Infectious disease

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Benzene is a known human carcinogen causing leukemia, yet ambient air quality objectives for benzene are not available in China. The ambient benzene levels at four background sites in China’s most developed coastal regions were measured from March 2012 to February 2013. The sites are: SYNECP, in the Northeast China Plain (NECP); YCNCP, in the North China Plain (NCP); THYRD, in the Yangtze River Delta (YRD) and DHPRD, in the Pearl River Delta (PRD). It was found that the mean annual benzene levels (578-1297ppt) at the background sites were alarmingly higher, especially when compared to those of 60-480pptv monitored in 28 cities in the United States. Wintertime benzene levels were significantly elevated at both sites (SYNECP and YCNCP) in northern China due to heating with coal/biofuels. Even at these background sites, the lifetime cancer risks of benzene (1.7-3.7E-05) all exceeded 1E-06 set by USEPA as acceptable for adults. At both sites in northern China, good correlations between benzene and CO or chloromethane, together with much lower toluene/benzene (T/B) ratios, suggested that benzene was largely related to coal combustion and biomass/biofuel burning. At the DHPRD site in the PRD, benzene revealed a highly significant correlation with methyl tert-butyl ether (MTBE), indicating that its source was predominantly from vehicle emissions. At the THYRD site in the YRD, higher T/B ratios and correlations between benzene and tetrachloroethylene, or MTBE, implied that benzene levels were probably affected by both traffic-related and industrial emissions.

Concepts: Hangzhou, Yangtze River, Suzhou, Regions of China, Nanjing, Shanghai, North China, Yangtze River Delta

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Abstract The striped stem borer, Chilo suppressalis (Walker), is an important pest of rice in China and other parts of the world. To further explore the population genetic structure and genetic differentiation of C. suppressalis populations found on rice in China, we amplified 432 bp fragments of the cytochrome b (cyt b) gene for 44 C. suppressalis populations. Nineteen variable sites in the mtDNA gene were observed, and 16 haplotypes were identified. Nucleotide diversity (π) and haplotype diversity (h) ranged from 0.00274 to 0.00786 and 0.72297 to 0.87604, respectively, while genetic structure analysis found significant genetic differentiation to be present among the five regions in China - northern China (NC), northeastern China (NEC), central China (CC), southern China (SC) and southwestern China (SWC) - where C. suppresalis was collected. In addition, molecular variance (AMOVA) showed that a relatively high proportion (57.6%) of the total genetic variance was attributable to variation within the populations. Nm and FST analyses suggested that the differentiation was not significantly different between NEC and NC, CC and SC, and SC and SWC regions, but was significant between NEC and CC, SC and SWC regions, corresponding well with the geographical distribution of the sampled populations. Phylogenetic analysis divided the populations into two indistinct clades: a NEC-NC-CC clade and a CC-SC-SWC clade, while CC region acted as a transition zone between north and south China, a finding different from previous work.

Concepts: Phylogenetic nomenclature, Haplotype, Evolution, Genetics, Population genetics, Biology, Regions of China, DNA