Thematic Lectures

A Few Recommendations and Suggestions on China’s S&T System and Policy Issues
Wang Zhizhen
Institute of Biophysics, CAS

Science and technology system is an issue that has been studied, practiced and also debated for years. The opinions of the management bodies are reflected in various documents such as decisions, plans, and programs are implemented. The opinions of the policy researchers are presented in words through thesis and reports, also exerting impacts. Yet，there are rarely occasions for the researchers at the research front to have the opportunities to express their ideas in a systematic manner. This report attempts to give a true and systematic reflection of the opinions and suggestions of the scientific and technological workers at the research front on this issue based on the results of questionnaires to CAS Members and relevant researchers. The restructuring of science and technology system is a big issue concerning the overall health and long-term development of S&T. The analysis, solutions and suggestions provided in the report are made in accordance with the strategic needs as proposed by President Hu Jintao and Premier Wen Jiabao which go as follows: “We must tightly seize the strategic opportunities led by the new round of world science and technology revolution, attach more importance to indigenous innovation, seek initiatives of economic development for the long run and formulate long-term competitive advantages, thus providing strong S&T support for the accelerated transformation of the mode of economic development” and we must “make S&T lead the sustainable development of China”, in an effort to enable the broad masses of the scientific and technological workers to “have more freedom in discussion, to be more concentrated in research, to enjoy more freedom in exploration and to carry out cooperation with more willingness”. This report focuses on discussing three underlying structure and policy issues that affect China’s current and future development of S&T, namely, the issue of over-administration in S&T management, the tendency of anti-market sentiments in S&T structure reform and the issue of seeking excessive interests in S&T activities.

Climate change is one of the greatest challenges human society faces in the 21st century as it is critical to human survival and development. There are two conflicting opinions on climate change in the international scientific community. One opinion is that global warming is happening as represented by IPCC, which is prevalent at present. Its core conclusion is that the ongoing global warming is mainly a result of greenhouse gas emission. The other view point is that the current climate warming is just a normal fluctuation of the climate which is mainly caused by natural factors and that human activities are just a minor one. This presentation focuses on the discussion of the following issues after presenting the above-mentioned opinions: (1) observed evidences of climate change; (2) the impacts of natural factors and human activities on climate change; and (3) the correlation between climate warming and carbon emission.

Through analysis, it gives the following basic conclusions: (1) climate warming is true but there exists uncertainty on the extent of warming; (2) both human activities and natural factors are having impacts on climate change, but it is difficult to quantify their relative contributions; (3) though IPCC has concluded that the increased concentration of greenhouse gases such as CO2 is the main cause of global warming, the scientific community has not reached a consensus on it. In addition, the presentation proposes a new approach for consideration on the quantification of global emission reduction based on the UNCCC principles of common but differentiated responsibilities and acting according to their respective capabilities. It also sets forth suggestions on China’s strategies and initiatives for addressing and adaptation to climate change.

Sustainable Development of Nuclear Energy
Zhan Wenlong
Chinese Academy of Sciences

Nuclear fission energy is a clean, safe, reliable and competitive energy source and is an important component in China's energy development. Its development can greatly contribute to the addressing of the climate change challenge through the reduction of greenhouse gas emissions and of air pollution. At present, nuclear power is a significant producer of the world’s electricity. With about 430 nuclear power units in operation all over the world, a total installed-capacity of over 370GWe, and over 40 units under construction, nuclear power provides about 16% of the world’s total electricity supply. There is a higher percentage of electricity generated from nuclear power in the developed countries with 75% in France and about 20% in the United States. Altogether 11 nuclear power units have been built and put into production in China with a total installed-capacity of 9.1GWe and 24 nuclear power units are under construction with a total installed-capacity of 25GWe. According to the relevant development plan, the installed-capacity of nuclear power in China will reach above 70GWe by 2020. It is obvious that China now has the largest number of nuclear power plants under construction in the world.

Nuclear fuel cycle is one of the most important processes in nuclear power production, which includes the fuel mining and fabrication, nuclear fuel burn-up and spent fuel reprocessing. In this process, nuclear safety is a top priority and a key factor to the sustainable development of nuclear energy. For decades, the once-through nuclear fuel cycle without the reprocessing of spent fuel seems to be the option of choice for the majority of the countries in the world due to economic and technical reasons. This could avoid the technological difficulty of reprocessing spent fuel for the short term，reduce the costs and also the possibility of nuclear proliferation. Yet a large number of long-live (a few million years) high-level radioactivity spent nuclear fuel made it impossible to guarantee the safety and reliability of the long-term storage of the fuel in the geological repository. Therefore, closed fuel cycle has been used in the transmutation of spent fuel, which can also help improve their efficiency. Some kinds of nuclear reactors, such as hard neutron spectrum reactors, especially accelerator-driven sub-critical system (ADS), if adopted for the transmutation of nuclear waste, can drop the half-life of the radioactive nuclear waste from a few millions of years to about 700 years, thus making it possible to carry out their geological disposal and packaging with materials.

Up to now, most of the nuclear power reactors in operation in the world belong to Generation two and the ones under construction which will be safer and more reliable are Generation three. The more advanced reactors are Generation four, which represent the future development of nuclear power. It will improve nuclear safety, enhance proliferation resistance, minimize waste, maximize natural resources utilization, reduce the costs to build and run such plants. The research work on sodium-cooled fast reactor and high temperature gas reactor has been going on in China for more than ten years. China is also interested in other Generation four reactors such as molten salt reactor and lead-cooled fast reactor, etc.

Although the IAEA data indicate that the world’s explored reserves of uranium can last more than 80 years, the situation that China faces is much severer than what the statistics can imply in terms of long-term and stable supply of uranium materials due to the lack of reserves in the country itself. So there remains a huge task for China to address for the sustainable development of its nuclear fission energy. Currently, in addition to finding pathways to burn 238U in fast reactor, thorium-uranium fuel cycle is another alternative which aims to use China’s relevant abundance of thorium-uranium materials for nuclear energy for over a thousand years. The extraction of uranium from the ocean is another way to meet the fuel supply. Nevertheless, even if all the scientific and technological challenges were met, what approaches would be eventually adopted will depend on the price–performance ratio.

Transgenic Technology: Research and Application
Chen Xiaoya
Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, CAS

A gene is the basic unit of heredity in a living organism. It is a stretch of deoxyribonucleic acid (DNA) whose coding sequence contains genetic information for its biological function. With the development of molecular biology, scientists are now able to transfer a given gene into the genome of an organism, and the resultant organisms are called “genetically modified organisms” (GMO). Transgenic technology has become an indispensable experimental tool widely used in many fields of life sciences. In agriculture, it has revolutionized crop breeding.

Since its commercialization for the first time in 1996, GM crops have been rapidly developing with a total planting area of 134 million hectares worldwide in 2009，of which 3.7 million were in China, ranking it 6th in the world. Cotton is a major GM crop in China; others include poplar, tomato, papaya and sweet pepper. It is documented that, up to 2008 transgenic insect-resistant cotton had been extended to 21 million hectares and had brought about huge social and economic benefits, including more than 25 billion RMB additional incomes to the farmers, and an annual reduction of chemical pesticides by 10,000 to 15,000 tons, having significantly improved the ecosystems of cotton fields.
Transgenic technology has great potential in increasing crop yield and improving quality. However, up to now, most GM crops are of insect-resistance or herbicide-tolerance. Although Bt insecticide proteins can greatly enhance the crop resistance to insect herbivores, they are highly specific and effective to only a certain group of insects, such as lepidopterons. To date, there has been no clear evidence showing that GM food is unsafe for human and mammal consumption. Yet, compared to traditional natural food, GM food is a new product and requires stricter regulations and supervision.
A special issue of Science, published in February, 2010, claimed that GM crops will become an important approach to solve the world food crisis and will play an important role in the world food security in the future. China has the largest population in the world and agriculture is of paramount importance. It is our national strategy to develop new technologies, including transgenic technology as powerful tools to address our food issue and environmental problems. So, it is of urgent importance for us to strengthen scientific education, and to establish effective and reliable platforms for communications between the public and the scientific communities. To guarantee a good job in this regard, government departments, seed companies, scientists, media and the public need to work hand in hand.