【摘要】 通过对过去数千年的地震以及数百年的旱涝变化的研究，对中国２１世纪地震、洪涝趋势进行了探讨，研究认为，２１世纪的上半叶，我国的自然灾害态势较为严峻，可能将会面临地震多发，干旱期来临等状况，而２１世纪的下半叶，我国的自然灾害态势将会逐步缓解，地震可能将会进入一个平静期，气候也将可能转为多雨期。在此基础上，文中尝试性地提出了一些２１世纪的自然灾害防治策略。更多还原

【Abstract】 Natural disasters pose major threat to large parts of the world. China is one of a few countries in the world with the highest level of natural disasters. Natural disasters occurred in China are characterized by multiple categories, high frequency, great seventy, and widespread distribution. The seven major kinds of natural disasters, which are meteorological, flood, oceanic, earthquake, geologic, disease and insect infestation of crops, and forestry disasters, caused great economic losses every year. As social and economic development progresses and urbanization occupies more and more areas, the economic losses due to natural disasters are increasing more rapidly. Since 1949, the natural disasters caused an annual average life losses of 20-30 thousand people, and resulted in a great economic losses. So the natural disasters have become one of the most important factors to hamper the development of China, especially earthquake, drought and flood. In order to reduce the disaster losses in the 21st century in China, one must know the possibility that earthquake, drought and flood disasters occur in China in the 21st, century. Based on the paleo-seismological and historical seismobogical data from 12,000aB.P. to present we found that earthquake in China had quasi-20a and quasi-300a active-moderate periods. In 20th century, there were five quasi-20a earthquake periods in China. The last quasi-20a period began since 1988, in which China had many destructive earthquakes such as Lijiang earthquake, Taiwan earthquake, and will end in 2001-2002. The last quasi-300a period began since 1815, and will end in 20362090. So it should be speculated that there will be two active periods of earthquake in the first half of 21st century in China, which may last from 2011-2025 and 2037- 2050, and that China may has a moderate period of earthquake in the second half of 21st century. Also based on monitoring and historic meteorological data from 1470 to 1998 in China, we found that transportation of drought and waterlogging stages had 21a and 50a periods, and the last waterlogging term began since 1990 and should end in about 2010. It can be speculated that China will suffer a serious drought term from 2010- 2040, in which China will need more water resources because of its economic progress and population growth. It can be revealed that China will have a more disaster stage in the first half of 21st century, and will have a less disaster term in the second half of 21st century. In the end of this paper, we put forward some suggestions about the countermea- sures for disaster reduction of China in the 21st century.更多还原