摘要
There have been significant variations in wind activity over the past five decades in arid and semiarid areas in China.High wind activity occurred from the 1960s to the 1970s,but wind activity has de-creased continuously from the 1980s to the present;as a result,the potential sand transport during the latter period was only 20%-50% of the values during the 1960s and 1970s.Phases of high wind activ-ity were highly consistent with the trends in desertification over the past five decades in arid and semiarid areas in China,but spring precipitation was also a significant factor:rapid desertification during the 1960s and 1970s was due to high wind activity,generally combining with low spring pre-cipitation;subsequent rehabilitation since the 1980s has resulted from the combined effects of low wind activity and higher spring precipitation.Therefore,although modern desertification and rehabili-tation processes are being more or less affected by human activities,both processes appear to be more strongly controlled by climate change.
There have been significant variations in wind activity over the past five decades in arid and semiarid areas in China. High wind activity occurred from the 1960s to the 1970s, but wind activity has decreased continuously from the 1980s to the present; as a result, the potential sand transport during the latter period was only 20%-50% of the values during the 1960s and 1970s. Phases of high wind activity were highly consistent with the trends in desertification over the past five decades in arid and semiarid areas in China, but spring precipitation was also a significant factor： rapid desertification during the 1960s and 1970s was due to high wind activity, generally combining with low spring precipitation; subsequent rehabilitation since the 1980s has resulted from the combined effects of low wind activity and higher spring precipitation. Therefore, although modern desertification and rehabilitation processes are being more or less affected by human activities, both processes appear to be more strongly controlled by climate change.
基金
the National Natural Science Foundation of China(Grant No.40301006)
关键词
中国
干旱半干旱地区
土壤荒漠化
风向
wind activity, desertification, response, over the past five decades, arid and semiarid areas in China
