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        Sand Storms Trigger Alarm

        2010-03-15 07:19:10LILI
        Beijing Review 2010年14期

        Pollution caused by sandstorms is a sharp reminder of the need for greater transnational efforts in fighting desertification

        By LI LI

        After an unusually humid winter with at least 10 snowfalls in Beijing, a severe sandstorm blown by strong winds bringing with it thousands of tons of desert sand took many residents of the city by surprise.On the morning of March 20, Beijingers woke up to see clouds of yellow dust in the air and a sky that was an ominous orange in color. The loose soil and dust that had traveled hundreds of miles from deserts in Mongolia and China’s northwest blanketed Beijing’s streets, covering parked vehicles, bikes, roofs and even plant life,as well as making its way into people’s homes.

        People were forced to close the windows of their homes and vehicles in order to keep the air inside breathable. Most pedestrians running unavoidable errands wore face masks and hurried through the streets.

        Most parts of the city were battered by strong winds throughout the day. In Changping District in the northern suburbs,winds swept through the streets at speeds of up to 100 km per hour.

        “The snowfall certainly curbed local dust flows, but sandstorms cannot disappear completely as long as their sources still exist,” said Guo Hu, head of the Beijing Meteorological Station, referring to China’s 1.67 million square km of desert.

        “The sources of sandstorms that are nearest to Beijing are the deserts of the Inner Mongolia Autonomous Region, which are only 800 km away,” said Guo. “While the slowest train needs 12 hours to cover the distance, sandstorms need only seven hours.”

        Beijing has been notorious for sandstorms throughout its history. During a single sandstorm in April 2006, at least 300,000 tons of sand poured down on Beijing. However, people believe that the situation has been remedied significantly in the past decade through intensified environmental efforts, including forestation projects in the northwestern and northern regions of China.

        The density hovered above 1,000 micrograms per cubic meter in Beijing’s city proper that morning, causing serious pollution. Beijing’s weather bureau ranked the air quality as a rare level five, the worst possible pollution grade. This essentially means that the air was hazardous to breathe, with a pollution reading of over 301.

        According to the China Meteorological Administration (CMA), the effects of the sandstorm that wreaked havoc in Beijing and swept across the country between March 19 and 21 were felt by a total of 21 provinces, municipalities and autonomous regions on the Chinese mainland. The air pollution index in Hong Kong shot to its highest level ever on March 22,mainly due to the sandstorms.

        The scenic city of Hangzhou in east China’s Zhejiang Province and renowned for its lake views, was blanketed with haze on March 22.

        Fujian Province, on China’s southeastern coast, was also shrouded in haze. Visibility in many cities in the province was down to approximately 3,000 meters.

        According to the Xinhua News Agency,Tu Jingfang, a pediatrics doctor with the Jiangsu Hospital of Chinese and Western Medicine in east China’s Jiangsu Province,said the department had seen a sharp increase in the number of asthma patients since the weekend, which could be attributed to the hazy weather.

        The massive sandstorm that hit Beijing on March 20 was closely followed by a second one, which affected Beijing and much of east China on March 22. It compelled the Beijing Municipal Environmental Monitoring Center to rank the air quality at a“l(fā)evel four,” meaning that it was hazardous with moderate pollution.

        The CMA forecast on March 31 that with active cold waves affecting vast areas in China followed by dramatic temperature fl uctuations in the first half of April, the northern regions could suffer from further sandstorms.

        Causes and measures

        “The reason that people feel sandstorms are particularly serious in 2010 is mainly because this year’s first sandstorm occurred on March 11, the latest time that the year’s first sandstorm has occurred for the past 10 years,” said Zheng Jiangping, an expert on disaster response and reduction with the CMA. Zheng said that all of the six sandstorms affecting China in 2010 occurred during the last 20 days of March, giving people the impression that sandstorms strike frequently.

        Zheng said that in actuality, the occurrence of six sandstorms from January to March equals the average rate for the past 10 years. The worst of these sandstorms, which affected 21 provinces,municipalities and autonomous regions in China, was ranked as a “strong sandstorm” on the CMA’s sandstorm scale,instead of the worst sandstorm on the scale, which is an “extremely strong sandstorm.”

        According to Zheng, the occurrence of sandstorms is mainly due to unique weather conditions, including a sudden rise of temperature in China’s neighboring country of Mongolia and China’s Inner Mongolia Autonomous Region in March, which led to accelerated thawing of soil, cold waves and frequent windy days in north China, as well as strong Mongolian cyclones. This is the exact weather system that near sources of sand and dust can trigger and facilitate the development of sandstorms.

        Attempting to refute the idea that these sandstorms were the latest sign of desertification in China, the CMA said China’s newly added deserts, which are declining in area every year, account for only 6 percent of China’s original deserts.

        “The deserts have been there for millions of years and cannot be brought under human control in such a short period of time,” said Yu Xinwen, a spokesperson for the CMA. Yu went on to say that China’s sandstorms have been less and less since the mid-1980s. He said that the average annual occurrence of sandstorms in China had dropped from 22 times in the 1980s to 16 times in the 1990s, and to 12 times between 2001 and 2009.

        However, a monitoring paper on China’s pastoral areas issued by the Ministry of Agriculture in March 2009 painted a less optimistic picture of deserti fi cation in China.According to the Guangdong Province-based newspaper Southern Weekend, while the ecological systems of some pastoral areas were recovering, grassland degradation and desertification were still serious. The paper was quoted as saying that 13.33 million hectares of China’s protected natural grasslands suffer from soil erosion.

        (Source∶ China’s Meteorological Administration)

        “China’s deserts are mainly located in areas around continental rivers, and could expand once the water fl ow dwindles in the middle and lower reaches of such rivers and land degradation ensues,” said Wang Jihe,head of the Gansu Desert Control Research Institute, to Southern Weekend.

        During an interview on March 22, Liu Tuo, head of the anti-desertification branch of the State Forestry Administration, said his branch would continue to increase the area of grassland and forests to reduce sand sources, which he regarded as the key measure for reducing the occurrence of sandstorms. “We will introduce plant species that best suit the local conditions, whether they be arbors, bushes or grass,” said Liu. He also listed other major measures on his agenda for reducing sand sources, including prohibitions on overgrazing, excessive farming and mining, reconverting farmland to forests or pastures, and building water-conservation irrigation facilities.

        International Cooperation

        Zheng told Beijing Review that in order to accurately monitor sandstorms, China has cooperated with Mongolia and South Korea in the establishment of a data-sharing mechanism between their sandstorm monitoring stations.

        Wang said that the grassland desertification trend on the Mongolian Plateau within the borders of Mongolia, another major source of sandstorms in Asia, has not yet been reversed due to mining, overgrazing and falls in underground water.

        He also said that Mongolia faces a lack of resources in fi ghting deserti fication due to its fi nancial dif fi culties,small population and vast grasslands threatened by deserti fi cation.

        In carrying out international cooperation to combat desertification,China has provided technical assistance to other countries. The Gansu Desert Control Research Institute, one of China’s leading academic institutes in desert studies, has been appointed by the Ministry of Commerce since 1993 to hold regular training programs on promoting desert control technologies, with some students hailing from other countries such as Mongolia.

        The institute has signed cooperative agreements with the Mongolian Government for training Mongolian desert-control workers and implementing joint anti-desertification projects.Governments and non-governmental organizations from China, South Korea and Japan have provided funding and technical assistance to Mongolia’s anti-deserti fi cation initiatives. China began to receive governmental and non-government aid for its treeplanting projects from South Korea and Japan as early as the 1980s. Some cities from China’s Inner Mongolia Autonomous Region have also been offering fi nancial and technical aid for tree-planting campaigns in Mongolian border regions for the last six years.

        “In fighting and controlling deserts,people of different countries are on the same page,” said Wang. ■

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