摘要
通过对相关历史文献的整理、统计和分析,研究1421-1950年青海东部农业区干旱灾害的等级序列、阶段性和周期性特征以及驱动力因子。结果表明:1421-1950年青海东部农业区共发生旱灾152次,平均3.5年发生1次。其中,轻旱64次,中旱63次,重旱20次,特旱5次,分别占旱灾总数的42.11%,41.45%,13.16%和3.29%。旱灾发生有5个高频阶段和3个低频阶段,1481-1499年、1711-1721年、1758-1780年、1861-1900年和1921-1940年是旱灾发生频率较高时段,平均1.55年发生1次旱灾;1421-1480年、1541-1600年和1781-1830年是旱灾发生频率较低的时段,平均8.1年发生1次旱灾,且均处于气候相对温暖期。小波分析显示,青海东部农业区的旱灾等级存在50～58年、25～32年、10～15年的年代际较长周期和3～5年的年际短周期。青海东部农业区旱灾的发生是气候变化、降水量时空分布不均和人为因素共同作用的结果,其中,气候因子起决定性作用,农垦开荒和战争等人为因素造成的环境破坏也对旱灾的发生起到了重要作用。
In this paper,the characteristics of drought disasters and their driving forces in the agricultural regions of east Qinghai Province during the period from 1421 to 1950 were researched after collecting and analyzing the relevant historical documents.The results show that 152 drought disasters occurred in the agricultural regions of east Qinghai Province during the period from 1421 to 1950,including 64 slight drought disasters,63 moderate drought disasters,20 serious drought disasters and 5 extremely serious drought disasters,they accounted for 42.11%,41.45%,13.16% and 3.29% of the total respectively,and drought disaster occurred once every 3.5 years.There were 5 high-frequency periods of occurring drought disasters（1481-1499,1711-1721,1758-1780,1861-1900 and 1921-1940）,and drought disaster occurred once every 1.55 years;there were also 3 low-frequency periods（1421-1480,1781-1830 and 1541-1600）,and drought disaster occurred once every 8.1years.Wavelet analysis shows that there were the 50-58,25-32 and 10-15-year long-term periods of drought grades in the agricultural regions of east Qinghai,and there was also a 3-5-year short-term period.Drought occurrence in the agricultural regions of east Qinghai was the joint result of climate change,uneven spatiotemporal distribution of precipitation and human activities,especially the effects of climatic factors,and then those of human factors,such as land reclamation and wars.
出处
《干旱区研究》
CSCD
北大核心
2011年第6期921-927,共7页
Arid Zone Research
基金
教育部人文社会科学基地项目(05JJD770014)
国家自然科学基金项目(40571004)
关键词
干旱灾害
旱灾等级
旱灾周期
农业区
青海
drought disaster
drought grade
drought period
agricultural region
Qinghai Province
