中国荒漠化潜在发生范围的修订

 为了客观反映中国荒漠化发生区域，按照联合国防治荒漠化《公约》的定义，利用1950-1990年间全国671个气象站的长时间序列气象数据，分别采用Thornthwaite和Penman计算可能蒸散量的方法计算了湿润指数的分布，然后根据中国气候区划和中国植被区划以及中国荒漠化发生的特点等对计算结果进行了调整，对中国荒漠化潜在发生范围进行了修订，明确了荒漠化各气候类型区的地理涵义。研究结果表明：①《公约》定义的荒漠化潜在发生范围及各气候类型区的划分标准不完全适用于中国。②中国的荒漠化发生在极干旱区、干旱区、半干旱区和亚湿润干旱区。极干旱区对应极旱荒漠，干旱区对应典型荒漠、草原化荒漠以及荒漠草原，半干旱区对应典型草原，亚湿润干旱区对应草甸草原中偏干旱的部分。③修订后中国荒漠化潜在发生范围总面积约4 524 089.1 km²，约占国土总面积的47.1％，其中亚湿润干旱区、半干旱区、干旱区和极干旱区分别占12.6％、28.8％、34.4％和24.2％。荒漠化潜在发生范围修订后比修订前增加1 207 056.9 km²，其中亚湿润干旱区面积减少，半干旱区、干旱区和极干旱区面积增加。

A Revised Potential Extent of Desertification in China

Based on the definition of desertification from the United Nations Convention to Combat Desertification, the potential extent of desertification in China was revised by employing Thornthweites and Penmans formulae to calculate humidity index using the records of 671 meteorological stations from 1950 to 1990, and the biogeographical features of the climate types were clarified. The calculated result was adjusted according to the climate division and vegetation division of China and the characteristics of desertification development of China. The results show that: ①The potential extent of desertification and the criteria for climate division defined by the United Nations Convention to Combat Desertification are not applicable to all cases in China. ②Desertification occurs in extremely arid, arid, semi-arid and sub-humid areas in China. The extremely arid area corresponds to extremely arid desert, the arid area corresponds to desert, steppe desert and desert steppe, the semi-arid area corresponds to steppe and the sub-humid area corresponds to the drier part of meadow steppe. ③The revised potential extent of desertification in China is about 4524089.1 km2, accounts for about 47.1% of the total terrestrial area of China, in which, sub-humid, semi-arid, arid and extremely arid areas account for 12.6%, 28.8%, 34.4% and 24.2% respectively. The potential extent of desertification increased 1207056.9 km2 compared to the former results after revision, sub-humid area decreased, semi-arid, arid and extremely arid areas increased.