Research progress of heavy metal pollution in China: Sources, analytical methods, status, and toxicity

Heavy metal pollution is one of the most serious environmental problems in China and a large number of people are threatened by heavy metal pollution.Extensive damage to human organs,such as liver,kidney,digestion system,and nervous system can be caused by uptake of excess heavy metals.Heavy metals in the environment can originate from both natural and anthropogenic sources.Although contamination of heavy metals has been known to be a severe environmental problem for decades,it is still getting worse in recent years and there are few feasible approaches to resolve this problem.Due to their high toxicity,prevalent existence and persistence in the environment,lead(Pb),mercury(Hg),cadmium(Cd),chromium(Cr) and arsenic(As) are commonly considered as the priority heavy metals which should be concerned and their emission should be controlled in China.This paper reviewed the pollution of heavy metals in China,focusing on the following four aspects:current status of heavy metal pollution in China,sources of heavy metals in China,toxicity and potential risk,and possible reduction strategies.     

CHINESE SCIENCE BULLETIN (KEXUE TONGBAO)

<正> Aims and ScopeChinese Science Bulletin, a comprehensive academic journal of China, is sponsored by the Chinese Academy of Sciences and published semimonthly (on 15 and 30 of each month) by Science in China Press. This journal aims at presenting the up-to-date scientific achievements of the highest standard and great significance in various fields of natural sciences in China for scientific workers in both China and foreign countries.     

Thermodynamic evolution of lithosphere of the North China craton： Records from lower crust and upper mantle xenoliths from Hannuoba

Lithospheric thinning in East China attracts much attention of geologists. In many cases where a lithospheric thinning is inferred, the trigger for instability is a preced-ing episode of crustal thickening by the continental colli-sion[1]. Lithospheric processes (e.g. lithospheric thinning) could be recorded by the thermal history of the lower crustal and upper mantle xenoliths. Xu et al.[2] suggested that the cooling (from >1200 to 850℃) recorded by spinel harzburgite from Northeast China …     

The outbreak pattern of the SARS cases in Asia

The severe acute respiratory syndrome (SARS) caused tremendous damage to many Asia countries, especially China. The transmission process and outbreak pattern of SARS is still not well understood. This study aims to find a simple model to describe the outbreak pattern of SARS cases by using SARS case data commonly released by governments. The outbreak pattern of cumulative SARS cases is expected to be a logistic type because the infection will be slowed down due to the increasing control effort by people and/or due to depletion of susceptible individuals. The increase rate of SARS cases is expected to decrease with the cumulative SARS cases, as described by the traditional logistical model, which is widely used in population dynamic studies. The instantaneous rate of increases were significantly and negatively correlated with the cumulative SARS cases in mainland of China (including Beijing, Hebei, Tianjin, Shanxi,the Autonomous Region of Inner Mongolia) and Singapore. The basic reproduction number R0 in Asia ranged from 2.0 to 5.6 (except for Taiwan, China). The R0 of Hebei and Tianjin were much higher than that of Singapore, Hongkong, Beijing, Shanxi, Inner Mongolia, indicating SARS virus might have originated differently or new mutations occurred during transmission. We demonstrated that the outbreaks of SARS in many regions of Asia were wall described by the logistic model, and the control measures implemented by governments are effective. The maximum instantaneous rate of increase, basic reproductive number, and maximum cumulative SARS cases were also calculated by using the logistic model.     

Rationality of 17 cities＇ public perception of SARS and predictive model of psychological behavior

This study investigated the feature of Chinese peoples?perception of SARS by surveying a stratified sample of 4231 people from 17 cities in China, and primarily pro-posed a risk perception centered predictive model of psy-chological behavior in crisis. The results indicated that, negative SARS-related information, especially informationof personal interest, will arouse peoples risk perception ofhigh level, and lead to irrational nervousness or scare; but positive SARS-related information, including recovery in-formation and that with measures taken by government, can decrease the level of risk perception. In the middle of May, people felt the highest level of risk on the SARS pathogens; the following are the physical health condition and infectiv-ity after recovering from SARS; they are factors that needspecial attention. SEM result analyses supported our hy-potheses in that SARS-related information affect people抯coping behavior and mental health through their riskperception, the four indices of risk assessment, feeling ofnerv- ousness, coping behavior and mental health areeffective presentimental indices for public psychological behavior in risky events.     

Climate change in China in the 21st century as simulated by a high resolution regional climate model

Climate change in the 21st century over China is simulated using the Abdus Salam International Centre for Theoretical Physics (ICTP) Regional Climate Model version 3 (RegCM3). The model is one-way nested within the global model CCSR/NIES/FRCGC MIROC3.2_hires (Center for Climate System Research/National Institute for Environmental Studies/Frontier Research Center for Global Change/Model for Interdisciplinary Research on Climate). A 150-year (1951-2100) transient simulation is conducted at 25 km grid spacing, under the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (IPCC SRES) A1B scenario. Simulations of present climate conditions in China by RegCM3 are compared against observations to assess model performance. Results show that RegCM3 reproduces the observed spatial structure of surface air temperature and precipitation well. Changes in mean temperature and precipitation in December-January-February (DJF) and June-July-August (JJA) during the middle and end of the 21st century are analyzed. Significant future warming is simulated by RegCM3. This warming becomes greater with time, and increased warming is simulated at high latitude and high altitude (Tibetan Plateau) areas. In the middle of the 21st century in DJF, a general increase of precipitation is found in most areas, except over the Tibetan Plateau. Precipitation changes in JJA show an increase over northwest China and a decrease over the Tibetan Plateau. There is a mixture of positive and negative changes in eastern China. The change pattern at the end of the century is generally consistent with that in mid century, except in some small areas, and the magnitude of change is usually larger. In addition, the simulation is compared with a previous simulation of the RegCM3 driven by a different global model, to address uncertainties of the projected climate change in China.     

Projected changes in climate extremes over China in the 21st century from a high resolution regional climate model (RegCM3)

Based on a consecutive simulation of the 21st century conducted by RegCM3, changes in climate extremes over China are investigated, following abasic validation of the model performances in simulating present climate. The model is one-way nested within the global model of CCSR/NIES/FRCGC MIROC3.2_hires. A total of 150-years (1951-2100) transient simulation is carried out at 25 km grid spacing under the IPCC SRES A1B scenario. The indices of the extremesincludes SU (summer days), FD (frost days), GSL (growing season length) for temperature, SDII (simple daily intensity index), R10 (no. of days with precipitation 10 mm/d), and CDD (consecutive dry days) for precipitation. Results show that the model can reproduce both the spatial distribution and the values of the present day annual mean temperature and precipitationwell, and it also shows good performances in simulating the extreme indices. Following the significant warming, the indices of SU and GSL for warm events will increase while the indices of FD for cold events will decrease over China. Heavy precipitation events as measured by SDII and R10 show an general increase over the region, except the decrease ofR10 in the Northeast and central Tibetan Plateau andless change or decrease of it along the middle and lower reaches of the Yangtze River. Decrease of drynessas measured by CDD over northern part of China while increase of it over the Tibetan Plateau, Sichuan Basin and other places in southern China are simulated by the model. This leads to the less change of the regional mean CDD in the time series in the 21st century unlike the other indices, which show clear trend of change following the time evolution.     

Syntactic Features of Computer English

In recent years there has been an apparent upsurge of interest in English in China. A whole new mass of people want to learnEnglish, not for the pleasure or prestige of mastering the language, but for the key role the language of English is playing in the world of tech-nology and commerce. As English became the accepted international language of technology and commerce, it created a new generation oflearners who knew specifically why they were learning a language. As a result, more and more people attach great importance to scien-tech-nical English. It is therefore how computer English, a branch of English for Science and Technology (EST), comes into being .This paper fo-cuses on the syntactic features of computer English.     

TEACHING PRONUNCIATION TO EFL STUDENTS

pronunciation teaching is considered as a basic course in English as a foreign language teaching in China. As we all know that English is a tool of communication between Chinese people and the people abroad,it is very important to have good pronunciation in order to communicate effectively. Though that good pronunciation is necessary for the mastery of a foreign language is accepted as axiomatic by most teachers, yet how the idea translates into the methodologies and techniques of the FEL classroom is still a question. This article will introduce as well as discuss some research findings and some approaches that we may find effective in pronunciation teaching.     

Survey of nutrients and quality assessment of crab paste by 1H NMR spectroscopy and multivariate data analysis

Crab paste is a traditional and popular food for people in the coastal area of China.Visual inspection is currently the only method of quality assessment.We developed a new analytical method of a comprehensive survey of nutrients and quality assessment for crab paste based on a combination of 1 H NMR spectroscopy with multivariate data analysis.The aqueous extract of crab paste was dominated by amino acids,sugars,carboxylic acids,nucleotides and amines(including 19 first-time-reported compounds such as choline,uracil and guanosine).Two grades of crab paste had significant compositional differences in terms of amino acids,lactate,N-acetylglutamate,choline,dimethylamine,uridine,1-methylnicotinamide and 2-pyridienmethanol.These results provided important information on the grade-dependence of crab-paste composition,and demonstrated that NMR-MDA was effective not only for the comprehensive survey of nutrients,but also for quality assessment of crab paste.     

Information for Authors

Science China Press and Springer-Verlag Berlin Heidelberg 2010 Chinese Science Bulletin (CSB) is a multidisciplinary academic journal supervised by the Chinese Academy of Sciences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chinese scientists. All papers should be intelligible for a broad scien- tific audience. CSB is published three times every month from 2010.     

An analysis of the spatial and temporal changes in Chinese terrestrial ecosystem service functions

Since Westman(1977) and Ehrlich(1982) put forward the concepts of "the service of nature" and "ecosystem service functions",respectively,methods for conducting value accounting for them,and their practical application have become the subjects of intense study.Based on an overview of available research findings,we discuss three scientific hypotheses.First,the terrestrial ecosystem offers both positive and negative service functions.Second,changes in terrestrial ecosystem service functions lie not only in the number of ecosystem types and the coverage area of each type,but also in their quality.Third,the value of terrestrial ecosystem service functions should be assessed both in terms of the value stocked and the value added.We collected land use data from China during the period 1999-2008,and Normalized Difference Vegetation Index data based on remote sensing images from the Global Inventory Modeling and Mapping Studies for the same period.We then calculated and analyzed spatial and temporal changes in China’s terrestrial ecosystem service values over the 10-year period.Considering temporal change,the total value(stocked) of China’s terrestrial ecosystem service functions decreased from 6.82 trillion Yuan RMB in 1999 to 6.57 trillion Yuan RMB in 2008.During that period,the positive value decreased by 240.17 billion Yuan RMB and the negative value increased by 8.85 billion Yuan RMB.The decrease in total value lies mainly in the humidity control,soil formation,and waste recycling functions.The total value(added) of China’s terrestrial ecosystem service functions increased by 4.31 billion Yuan RMB in 2000,but decreased by 0.13 billion Yuan RMB in 2008(based on the constant price of China in 1999).The value(added) was a negative figure.From the perspective of spatial change,we can see that the supply of China’s terrestrial ecosystem service functions fell slightly over the past 10 years,mainly in Northeast and Southern China.As a result of human activities on ecosystems,the loss of ecosystem service functions’ value was relatively prominent in Shanxi and Gansu provinces,compared with an increase in value in Shaanxi Province.Terrestrial ecosystem service functions’ value per unit area was relatively high in mid-and East China,showing a prominent spatial change over the 10-year period,but low in Western China.Some conclusions are drawn after an in-depth analysis of the factors causing the spatial and temporal changes in China’s terrestrial ecosystem service functions,in the hope that our suggestions will be helpful for the management of China’s terrestrial ecosystems.     

Information for Authors

Chinese Science Bulletin (CSB) is a semimonthly multidisciplinary academic journal supervised by the Chinese Academy of Sci-ences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chi-nese scientists. All papers should be intelligible for a broad scien-tific audience.     

Information for Authors

Chinese Science Bulletin (CSB) is a multidisciplinary academic journal supervised by the Chinese Academy of Sciences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chinese scientists. All papers should be intelligible for a broad scientific audience. CSB is published three     

Information for Authors

Chinese Science Bulletin (CSB) is a semimonthly multidisciplinary academic journal supervised by the Chinese Academy of Sci-ences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chi-nese scientists. All papers should be intelligible for a broad scien-tific audience.     

Information for Authors

Chinese Science Bulletin (CSB) is a semimonthly multidisciplinary academic journal supervised by the Chinese Academy of Sciences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chinese scientists. All papers should be intelligible for a broad scientific audience.     

Information for Authors

Chinese Science Bulletin (CSB) is a semimonthly multidisciplinary academic journal supervised by the Chinese Academy of Sciences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chinese scientists. All papers should be intelligible for a broad scientific audience.     

Information for Authors

Chinese Science Bulletin (CSB) is a semimonthly multidisciplinary academic journal supervised by the Chinese Academy of Sci-ences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chi-nese scientists. All papers should be intelligible for a broad scien-tific audience.     

Method for quantification of aerobic anoxygenic phototrophic bacteria

Accurate quantification of aerobic anoxygenic phototrophic bacteria (AAPB) is of crucial importance for estimation of the role of AAPB in the carbon cycling in marine ecosystems. The normally used method 揺pifluo-rescence microscope-infrared photography (EFM-IRP)?is, however, subject to positive errors introduced by mis-taking cyanobacteria as AAPB due to the visibility of cyanobacteria under infrared photographic conditions for AAPB. This error could be up to 30% in the coast of the East China Sea. Such bias should be avoided by either subtracting cyanobacteira from the total infrared counts or using a flowcytometer equipped with specific detectors for discrimination between cyanobacteria and AAPB.     

The demonstration, decision process and practice of Three Gorges Project

The world-famous Three Gorges Project (TGP) is the largest hydropower station in the world and the largest water resources and hydropower project constructed in China.The impoundment of Three Gorges Reservoir reached the design water level of 175 m for the first time on October 26,2010,which indicated that the project had met design requirements of various functionalities of flood control,power generation and navigation.To complete the project it took nearly 100 years for conception,demonstration,design and construction of the TGP.How was the conception of TGP proposed? What kind of role should it be? What were the different opinions? How was the project demonstrated? What was the conclusion of demonstration? Those are the issues that many people care and don’t know about.To memorize the realization of the century dream of Chinese people and to record the history of development of TGP,the author presents a compendious introduction to the project.