On 28 August 2001, President JIANG Zemin cordially met distinguished scientists to attend the 10th International Strategic Meeting of Human Genome Sequencing at Zhongnanhai, Beijing.

Fourth Sino-American Symposium on Frontier Sciences Held in Beijing

The Fourth Sino-American Symposium on Frontier Sciences, which aimed at promoting the development of frontier and cross-disciplinary sciences in China and the United States, opened its ceremony on 21 September 2001. Nearly 80 outstanding young scientists from scientific institutions, universities and colleges of the two countries attended the three-day meeting.

Chunli BAI, Member & Vice-President of the Chinese Academy of Sciences, delivered an address at the opening ceremony. The Symposium focused on the following eight topics: advanced catalytic materials, scientific computation, biological network, evolution of dinosaurs, gamma-ray burst, mid-ridge seabed dynamics, graphic formation and vision process.

According to the organizational rules for the symposia on frontier sciences, attendees shall be young scientists who are excellent leaders in their own disciplinary fields. The ultimate solutions to many problems in frontier sciences will need the multi-disciplinary, inter-departmental and transnational cooperation. The Sino-American Symposium on Frontier Sciences will not only enhance the innovative spirit of our young scientists and promote mutual understanding and trust among the young scientists from the two countries, but also boost the development of frontier and cross-disciplinary sciences in China.
      

     New Mechanism for Running the Institute of Neurosciences Established

The Institute of Neurosciences, CAS, is a newly established institute, which tries to follow international practices in the organization and development of its scientific research team, the system of management and mechanism of operation.

In the organization and development of its scientific research team, the Institute has recruited qualified personnel from home and abroad through open advertisements. Sticking to the principles of high criteria and high requirements, the Institute has recruited nine group leaders successively. 

In order to build up an efficient management system and running mechanism, the Institute has streamlined the administration by canceling the original departments and offices, and establishing the secretary or executive secretary responsibility system under the leadership of institute director or deputy directors. An international advisory committee, which is composed of well-known scientists including Nobel laureates, was set up to advise on the major issues of the Institute, such as the orientations of scientific research, personnel employment, research group setup, and so on. They work together with the academic committee to evaluate the work of research groups. A council consisting of experts and leaders from inside and outside the institute was set up to provide consultations on major issues of the Institute. The reform on the management system and running mechanism has improved the efficiency of the Institute.
Basic Research
 High Quality MgB2 Superconductor Synthesized

The discovery of MgB2 superconductor by Japanese scientists in January 2001 aroused immediately great attention from the superconductor community, for the alloy superconductor has a high critical transition temperature of 40K, reaching or even surpassing the limit predicted by conventional BCS theory.

The State Key Laboratory of Superconductors, Institute of Physics, CAS immediately mobilized human resources to conduct research in the area. A few days later, they synthesized high quality single-phase samples in normal and high-pressure conditions respectively, and studied their relevant physical properties. The synthesized single-phase samples have perfectly pure structure diffraction spectrums and a superconductivity transition temperature of 40K; their resistance transition temperature is lower than 0.5K, and their Meissner diamagnetism 100%. Especially, the sample synthesized under high-pressure conditions is extremely dense. From the analysis of the magnetic return line detected at 20K, the system critical current density of the sample reaches 1’105A/cm² under the magnetic field of 1 Tesla, which is at the international leading level. Articles on the results will be published on the recent issue of China Physics Bulletin

Currently, the laboratory is conducting research on problems related to the superconductor, such as Hall effect, thermoelectric potential, tunnel spectrum and magnetic flow dynamics, while trying to grow single-crystal, membrane and higher temperature superconductors.

So far, the alloy superconductor has demonstrated excellent utility. For instance, the large critical current may provide large power transmission and high quality microwave devices; its large coherence length enables the preparation of better superconductor quantum inference devices that will greatly improve the sensitivity of detection when applied to terrestrial, oceanic and life sciences and weak magnetism detection under various circumstances; an even superior feature is that its ductility is much better than that of oxide superconductors

So far, the alloy superconductor has demonstrated excellent utility. For instance, the large critical current may provide large power transmission and high quality microwave devices; its large coherence length enables the preparation of better superconductor quantum inference devices that will greatly improve the sensitivity of detection when applied to terrestrial, oceanic and life sciences and weak magnetism detection under various circumstances; an even superior feature is that its ductility is much better than that of oxide superconductors.

Prof. Yongxiang LU, President of CAS,  was awarded the Werner Heisenberg Medal of German Humboldt Foundation by Prof. Wolfgang Fruehwald, Chairman  of the Foundation at the New Century Hotel, Beijing on 15 September 2001
First Case of Whole Sequencing of HaSNPV Reported in the World
Scientists from the Wuhan Institute of Virology (WIV), CAS, have recently completed the whole sequencing of the HaSNPV that exists in Chinese cotton bollworms in collaboration with Dutch scientists, marking the first time that the whole sequence of HaSNPV was determined. It is of important theoretical value to the study of the genomic structure and molecular evolution of bacilliform viruses. The achievement was made by the International Joint Open Laboratory of Invertebrate Virology, WIV,  in close collaboration with the Wageningen University of the Netherlands. HaSNPV is a pathogenic virus characteristic of cotton bollworms. It was first segregated by the WIV and has been used for the prevention of cotton bollworms since the 1970s. In 1993, the virus was registered as China’s first virus pesticide thanks to the efforts of the WIV and its partnership institutions. Currently, the annual yield of HaSNPV amounts to 200-400 tons, with an applied area of two million mu. A series of advances have been made by the WIV : the total length of HaSNPV is 131,403bp (its entry number in GenBank is:AF271059); there are 135 ORFs whose coding length is over 50 semicarbazides, including 110 homologous genes of bacilliform virus and 20 HaSNPV-characteristic genes.

By means of the “Gene Comparison Pareto Diagram” method, the study revealed for the first time the common features of the genome sequences of bacilliform viruses, which is of important significance to the study of the genomic structure and evolution of bacilliform viruses.

On 21 September 2001, Prof. Yiyu CHEN, Vice President of CAS, and Mr. Yamazaki, Vice President of IHI Inc., cut the ribbon at the Ceremony on the Establishment of Refuse Derived Fuel (RDF) Testing Production System.

First Strikethrough Ice Core Drilled on Mount Qomolangma Region

At the Puerto of Dongrongbu Glacier, which is 6,550m in altitude, a 116.8m strikethrough ice core was successfully drilled for the first time in the world. The expedition comprised 11 scientists and technicians.

The cross-section features of the ice core indicate that the thickness of the particle snow layer at the drilling point was more than 20m, which ensured the high fidelity of the ice core record. Because the drilling point was located at the Puerto of the glacier, the annual layer of the ice core here was thinned out only under the action of gravity and free from the disturbance that might occur when the glacier flowed, which was testified by the densely dotted small spherical bubbles in the whole ice core. The entire ice core is hardly contaminated except the 3m section at the bottom. Experts say that this section of the ice core should have been formed during the last glacial age or even earlier. Hence, the ice core provides a long chronological series of record of the monsoon evolution in the low-latitude, high-altitude area.

Cooperative institutions taking part in the project include: the Institute of Quaternary Climate, Maine University (USA), the Institute of Climate and Environment (France), the Institute of Ocean Physics (Korea) and the Institute of Botany, CAS.

Dr. Luming DUAN in the Forefront of Quantum Research

Lately, Nature, Science and Physical Review Bulletin have frequently carried the articles written by Dr. Luming DUAN from the University of Science and Technology of China (USTC), a young professor recommended by world-renowned academic authorities in quantum-related areas.

Luming DUAN was graduated from USTC with B.Sc. in 1994 and Ph.D. in 1998, under the supervision of Prof. Guangcan GUO, Director of the Open Laboratory of Quantum Communications and Computing (OLQCC), USTC. Dr. DUAN has since achieved a series of innovative results in quantum informatics and optics. In collaboration with Prof. GUO, he took the lead in advancing the method of error-avoiding quantum coding for tackling de-coherence problem in quantum information system, and advancing the brand-new concept of probabilistic quantum cloning (PQC) to study the optimum process of PQC. Their efforts were highly praised by the international peers, including Prof. Charles Bennett, an authority in quantum informatics, and widely quoted as the “Duan-Guo Limits”.

DUAN is currently a deputy director of OLQCC. For his remarkable achievements in the field of quantum informatics, DUAN became a specially invited reader to Physical Review Bulletin in 1999 and Nature in 2000. His paper, Entangled and Compressed Atomic 

Beams, which was published on Physical Review Bulletin at the end of 2000, presented new ideas and methods that are extremely valuable to quantum communications research. Dr. Lukin of Harvard University praised the article “to have turned a new page for the study of compressed states”.

In January 2001, DUAN and his colleagues co-authored an article, Preparation of Many-particle Entanglement with Bose-Einstein Condensate, which was published on Nature, integrating for the first time two hot frontier disciplines of physics, i.e. Bose-Einstein condensate and quantum informatics. In June 2001, DUAN published on Science an article on geometric quantum computation, which presented for the first time a feasible experimental solution that can overcome the main difficulties of the existing quantum computers. Prof. S. Lloyd from MIT commented on the achievement as saying: “Geometry has occupied an important position in human knowledge for over 2,000 years; …The work done by DUAN et al has enabled it to be used for ideal quantum computation, making it more flexible and resistant against noise and errors.”

 

Paleontological Research in China with Remarkable Achievements

Under the care and auspice of the Government, Chinese paleontological research team has expanded rapidly. By the end of 2000, the number of members of the Chinese Society of Paleontology (CSP) had exceeded 2,400, making CSP one of the largest paleontological societies in the world.

A large number of young and middle-aged paleontologists, who are dedicated to their research, have been brought up in New China. A series of major discoveries and notable accomplishments have been made. For example, the discovery of a series of Precambrian oryctocoenoses represented by the Weng’an Biota, whose fossils are so well preserved and diversified in content, is a surprise to the world; the discovery of the fauna in Chengjiang (Yunnan), which existed 530 million years ago, attracts the science community as “one of the most astonishing discoveries in the 20th century”. Moreover, the discovery of some important hominid fossils in Tangshan (Nanjing) and Hexian (Anhui), the progress in the study of primitive land plants, Huaxia flora, ginkgoales and angiosperms are highly appraised by the international paleobotanical community; the discovery and exploration of the primitive birds and feathering dinosaurs in the fauna along Rehe (the Hot River, Liaoning), are of extreme importance to the study of the origin and evolution of birds and feathers.

In recent years, Chinese paleontologists have published more than 20 papers on Science and Nature. Besides, Chinese paleontologists took the lead in studying the Huangnitang profile in Zhejiang and the Meishan profile in Changxing, which have recently been approved by IGU as the global boundary stratotype cross-section (i.e. “Golden Nail Section”). The Changxingjie and Lepingtong established by Chinese scholars have been listed in the International Geological Chronicle, and become the standards for international stratigraphic classification and comparison.

Prof. Chunli BAI, Vice President of CAS, received the 2001 SCI International Medal in London on 4 October 2001. On the right: Sir David Harrison, Chairman of the Evaluation Committee of SCI.

 Research & Application

Spirulina Containing DHA Screened Out First Time in the World

After several years of insistent efforts, Prof. Hongjun HU of the Wuhan Institute of Botany, CAS, in collaboration with his student Yeguang LI, successfully screened out for the first time in the world a species of spirulina that contains DHA.

Prof. HU has been engaged in the study of algae for over 40 years, and achieved a number of results in this field. He also took the initiative to industrialize the production of algae in China. The Yunnan Chenghai Lake Shipurui Corp. was founded on the basis of the Prof. HU’s research group.

Beginning in March 1998, they spent three years collecting more than one hundred specimens of spirulina in four strains from nine provinces. Through screening and separation, they finally identified a species that is adaptive to the temperature environment from 15-35 C°, and thus can grow perennially in many areas of China, not just limited to the tropical and subtropical regions. This has greatly increased the production cycle and potential yield of algae in China. The species, as tested by the Oil & Products Quality Supervision and Inspection Center of the Agriculture Ministry, is superior in quality to foreign species and, in particular, it contains 1% DHA, which is a kind of unsaturated fatty acid (called cetoleic acid) that plays a multiple role in preventing and curing cardiovascular diseases and cancers and adjusting the central nervous system and auditory system.

Research on Functional Carrot for Preventing Shift of 
Intestinal Toxin Witnessed Important Progress

After eleven years of hard experimental work, the research team led by Prof. Xinghua HONG, Shijiazhuang Institute of Agriculture Modernization, Chinese Academy of Sciences, have successfully developed a “carrot agent for intestinal tract microclimate conditioning (CM Carrot Juice)” (the invention has been patented in China), by adopting a scientific recipe which takes the cell sap of carrot as the basic raw material, and using a cell separation and cell wall-breaking technology to extract the cell sap. The CM Carrot Juice can effectively protect the intestinal barrier of the human body, prevent the shift of intestinal bacteria and endotoxin, and thus is of great importance to human health in the 21st century.

The shift of intestinal bacteria and endotoxin is an important subject for preventive and clinical medicine.

Studies show that the CM Carrot Juice can evidently protect the intestinal barrier of the adult mouse that is injured by intestinal ischemia reperfusion. According to the research results of the Cancer Institute, Chinese Academy of Medical Sciences, the CM Carrot Juice can obviously promote the growth and development of the intestinal villi and colon gland of a baby mouse that is fed on the agent, and effectively combat the noxious and other side effects of the chemical drug MTX upon the intestinal tracts. Using the electron spin resonance (ESR) technology, the Institute of Biological Physics, CAS, investigated the oxygen free radicals generated in the process of rat ischemia scathe and the effects of CM carrot juice feeding upon the generation of oxygen free radicals at low temperature. And in the result: the feeding of CM carrot juice evidently impedes the generation of oxygen radicals. It indicates that the CM carrot juice can considerably promote the proliferation of intestinal Dichotomobacilli and effectively protect the biological barrier of the intestinal tracts.

On 18 September 2001, Nobel laureate Prof. Samuel C. C. Ting, a distinguished scholar of American citizenship & foreign member of CAS, gave an invited lecture entitled “Searching for the most elementary particle in the cosmos”.

Information Technology

Ultrahigh Density Information Storage Technology Developed in China

After being magnified for a million times, a micrograph clearly displays a microworld that is usually unimaginable before us: on the nano-scale organic membrane material are distributed orderly information storage dots whose diameter are no more than 0.6nm.This ultrahigh density information storage organic material has recently been developed by Chinese scientists. The 0.6nm diameter indicates that the information storage density can reach 1014bytes/cm2, which is one million times higher than that of the existing CD ROM. Information storage, transmission and procession technology is one of the most important conditions for raising the integrated development level of society, and one of the focuses of international competition in the high-tech area. The developed countries have invested large amounts of human and financial resources in the research of ultrahigh density, ultrahigh speed data storage technology. The Institute of Physics, CAS designed a unique charge transfer organic molecular system that is used as the medium for information storage, and achieved ultrahigh density information storage by taking advantage of its electric bi-stability. The material has the unique features of stability, repeatability and erasability in molecular-scale storage. It will take another fifteen years to industrialize the technology.

Research & Development

“Research on Eco-environment Rehabilitation & Economic 
Sustainability of the Yangtze River Valley”  Passed Terminal Review

On May 30, 2001, “Research on Eco-environment Rehabilitation & Economic Sustainability of the Yangtze River Valley”, an A-class key project of the CAS launched during the “Ninth Five-Year Plan” period, passed the terminal review. The review panel chaired by Prof. Honglie SUN, Member of CAS, reached the following conclusions: in the past four years, the project staff have achieved fruitful research outcomes in seven different aspects, including the proposals on the zoning of the eco-environment in the Yangtze Valley and the environmental change in the source of the Yangtze River that have attracted high attention from the authorities concerned; new progress has been made in the research of flood disasters along the Yangtze River Valley, and the proposals such as integrated planning and management of rivers and lakes, attaching equal importance to water storage and drainage and returning reclaimed farmland to the lakes have provided a scientific basis for government decision-making; the tracing investigation on the implementation of the policy “returning cultivated land to forest” in the upper reaches of the Yangtze River has exposed the major problems and concerns, such as false reports, financial difficulty of the forestry sector and difficulty of the local peasants in making a living; and the tracing investigation of the reservoir areas prior to and after the damming off of the River has disclosed even more serious conflicts between man and land in the reservoir areas and the increased risk of eutrophication and algae plankton bloom when water is impounded in the reservoir.

CAS Vice President Dr. Zhu CHEN met Academician F. Fordov, Vice President of Russian Academy of Sciences during dinnertime on 24 July 2001. CHEN’s introduction on the CAS Pilot Project of the National Knowledge Innovation Program aroused great interest.

Chinese Scientists Tackled the Merzlota Problem in QTR Construction

The biggest problem in the engineering construction of the Qinghai-Tibetan Railway (QTR) lies in merzlota that threatens the firmness of the railway subgrade and the safety of the trains. The technical problem regarding merzlota has been tackled and thus the construction can be launched, according to experts and engineering technicians concerned.

The QTR will have to go through a merzlota area of 550 km in length, including a 190km-long perennial merzlota area that is less stable or unstable and a 100km-long high temperature merzlota area that is very unstable. What’s more, the merzlota along the QTR is special in that the Qinghai-Tibetan Plateau is low in latitude and high in altitude, with thin air, intense sunlight, little precipitation and large quantity of evaporation. Especially the sunlight and human activities combine to produce great effects upon the frozen ground temperature that might cause ice-out.

Experts say that China has invested great human and financial resources to study the merzlota along the QTR from many perspectives for a very long time, which is rarely seen in the world. As early as in the 1960s, merzlota experts represented by Guodong CHENG, Member of the Chinese Academy of Sciences, had been to the Qinghai-Tibetan Plateau to investigate the earth along the QTR. After many years of observational study, Chinese scientists have had a precise understanding of the subtle changes of merzlota, to the extent of -0.1-0.3 0C. Presently, the basic distribution characteristics of merzlota along the QTR have been figured out.

Scientists pointed out that different principles of treatment should be taken in the civil engineering of the Qinghai-Tibetan Railway construction subject to the various engineering geological conditions.

At the invitation of the Slovakian Academy of Sciences (SAS), CAS Vice President Bailing YANG headed a delegation for a formal visit to SAS. The two sides signed the CAS-SAS Scientific Cooperation Program for 2001-2005.

Quality Hybrid Rice “ZY-223”    Developed  by SCIB Passed Appraisal

The hybrid rice “ZY-223” developed by South China Institute of Botany (SCIB), CAS, was grown experimentally in various areas of Guangdong Province, including Chaozhou, Yunfu, Yangjiang and Zhanjiang, with excellent results. This variety of rice has a high yield, high resistance to rice blast, high quality that is 2-3 grades better than ordinary rice, and thus a good market price. The species has passed the provincial and national appraisal. 

“ZY-223” is a temperature-sensitive, medium-flowering and late-ripening quality hybrid rice by mixing the “Z-A” and “R223” rice species bred by SCIB itself. The average yield in the Southern China pilot cultivation area in 1999 amounted to 500.81 kg per mu, higher than the other species. In the production experiment, the average yield per mu reached 511.56 kg, ranking first among all rice species. “ZY-223” is superior in rice quality, yield and disease-resistance, strong in tillering ability and growth potential, and adaptive to various conditions. According to an adaptability report, “ZY-223” has a large area of optimum adaptive growing area.

“ZY-223” and its parents were all developed by SCIB and have been filed for intellectual property rights.


 International Cooperation 

CAS Cooperates with Mitsubishi Electric  to Develop ASP

A seminar on Application Service Provider (ASP), jointly organized by the Chinese Academy of Sciences (CAS) and the Mitsubishi Electric Corporation, was held in Beijing on June 8, 2001. Focusing on the terminal technology of LINUX-embedded systems, attendants discussed in depth the history, status quo and trends of ASP development in China and Asia. The meeting also presented a new ASP product---thin terminal, which was jointly developed by the CAS and the Mitsubishi Electric and gained high appraisal from experts in this field.

ASP is a novel type of business model that provides network services such as software, hardware, information and system solutions in the form of renting.

In November 1998, Chinese President JIANG Zemin visited a high-tech exhibition held by the Mitsubishi Motor Inc. during his visit to Japan. He spoke highly of the state-of-the-art technologies developed by the Mitsubishi Electric in various high-tech areas. “Sino-Japanese cooperation and exchanges in the area of high and advanced technologies will be enhanced, ” JIANG declared. His remark gave a strong impetus to the technical exchange and collaboration between CAS and Mitsubishi in a wide range of areas. The LINUX-embedded thin terminal technology presented at the seminar was just one of the important results of the bilateral cooperation.

Sino-German Cooperation on Nanotechnology

The First Sino-German Symposium on Nanotechnology and Microsystems was held at the Beijing Sino-German Science Promotion Center (SGSPC). Negotiations on specific items were conducted focusing on the preconditions for bringing this innovative technology into maturity, and four agreements were reached.

Nanotechnology and microsystem will bring tremendous changes to the way of our life in future. With the application of various high-performance novel materials, traffic and transportation will become safer and more comfortable, and better fit in with the requirements from the eco-environment. The meeting, jointly hosted by the CAS and the Daimler Kreisler Incorporated Company and sponsored by the SGSPC, presented the latest achievements of more than 60 experts from China or Germany who are specialized in nanotechnology and microsystem. Presentations and topics covered the following areas: carbon nanotubes, nanometer photo-electronics, nanometer composites, nanometer analytics, microscopical machine procession of microsystem, micro-manufacturing technology, micro-sensor system, nanotechnology and the applications of microsystem technology in automobiles and space systems.

During the symposium, Chinese and German scientists held negotiations on the specific items of preconditions for industrializing the technology, which led to the signing of four agreements on nano-instruments for electronic, chemical and biological applications, on nanotubes for energy conversion, on nanometer composites for surface layer protection and on nanosystems for environment sensing, respectively.

New Pattern of Carbon Bonding Arrangement Discovered

On June 29, Science carried an article co-authored by Chinese and American scientists, who announced that they had discovered in theory a quintuple-coordinated plane carbon compound (QPCC), which supplied a gap in the research on multiple-coordinated plane carbon compounds.

The first author Zhixiang WANG, a post-doc with the Georgia University, USA, collaborated with an American scientist in proving the rationality of the existence of QPCC. They identified three basic units containing QPCC. By inserting these units into a single or multi-ring hydrocarbon, they designed a new kind of molecule named “super-coordinated aromatic hydrocarbon”. They noticed that this new compound has an interesting property. That is, when the selected unit varies, the compound can maintain or convert the aromaticity (or anti-aromaticity) of the original parent hydrocarbon. It may have some new properties and can be used for designing new materials.

Digital Locust-Forecast System on Trial in Xinjiang

On the protective gratings around the Manas Grassland hang miniature digital remote sensors for monitoring swarms of locusts. Some Chinese and German experts are using the digital remote sensing technology and geographic information system to conduct locust forecast and experiments on their biologic characteristics.

The experiment was designed by Prof. F. Force from the Institute of Geography, Industrial University of Berlin, and Ailisil Kurban, Associate Professor of Xinjiang Institute of Ecology and Geography, CAS, an assistant to Prof. Force. They took the initiative in placing digital remote sensors (including visible light, infrared and sound sensors) in places where locusts might throng in the fields for collecting data about locusts. These data are then transmitted to the analysis center located in the Manas Locust Forecast Station, where the distribution density of locusts is analyzed by computers to forecast  the severity of locust plague.

Xinjiang is the place where suffers the most serious plague of locusts. The vast grassland of the Tianshan Mountain is afflicted with the potential hazards of mountain locusts, Italian locusts, hastate locusts, Siberian locusts and Asian locusts. Every year the locusts cause a reduction in at least 3.5 billion kg of herbage and a direct economic loss of over 700 million yuan.

The IVth Sino-American Symposium on Frontier Sciences was held at the Cuigong Hotel, Beijing from 20 to 23 September 2001, with approximately 70 young scholars attending the meeting.

Briefs

Hydrogen Atomic Clock Developed by Shanghai Observatory

The four hydrogen atomic clocks (HACs) and time-division systems provided by Shanghai Observatory, CAS (SOCAS), were installed on the “BD-1” Satellite Guiding & Positioning System, making outstanding contributions to the successful construction and operation of the System.

With a strong basis in TF standards, TF measurement, synchronization technology and atomic time theory research & application, SOCAS is the principal institution specialized in the research and development of HACs in China. More than 20 units of practical HAC have been produced since it was developed in 1987. They are extensively applied to scientific projects such as “China VLBI Network” and “BD-1”, and some are exported to Australia. Their operation proves perfect.

Presently, SOCAS is planning to carry out research on satellite-borne HAC in order to meet the domestic urgent demands for the second-generation satellite guiding systems.

Breakthrough Achieved in Poisonous Weed Control Technology

Toxic plants have a wide distribution on the natural grasslands in China. The ratio of livestock poisoned or killed by toxic weeds has been increasing year by year, producing a serious impact on the development of stockbreeding.

The Cold & Arid Regions Environmental and Engineering Research Institute, CAS, has conducted long-term study on the poisonous weeds of the grassland. Recently, a breakthrough has been made in the poisonous weed control technology: an effective chemical weeding technology for Euphorbia fisheriana and Oxy tropis was developed, and the chemical has been disseminated on a large scale in Gansu Province since June 15, 2001. The total area using the technology in the counties of Sunan and Tianzhu and the livestock farm of Huangcheng, Gansu Province has amounted to 10,000 mu.