摘要
中国北方东部地区2001—2002年春季降尘量分布特征的研究表明,研究区平均春季降尘量为127.05t·km^-2,约占全年的一半,且主要集中在3、4月;春季降尘以近源沉积为主,因此降尘量的空间分布主要受局部环境的影响;除中沙外,降尘总量和降尘中其他组分的沉积量随距离均呈现指数递减趋势,且粒度越大的颗粒物,其半衰距离越短;更新世时期黄土高原平均每年流失的黄土至少已达1亿t,现在黄土高原每年实际流失的黄土大约为14.4亿t,如以此侵蚀速度持续下去,黄土高原将在6.6-13.2万a之内被侵蚀完毕。
The distribution characteristics of spring dustfall during 2001-2002 at 28 sites are analyzed in the east part of Northern China.The results show that the spring dustfall occur mainly in March and April with the amount of 127.05 t·5km^-2,occupying about 50% of the whole year dustfall;Spring dustfall are mainly from local region source,so the spatial distribution of dustfall is controlled mainly by the character of local underlying surface;Except for medium sand,the total dustfall and the amount of different grain size decrease exponentially with distance,and their “half-attenuation distance” decrease with the increase of grain size;The loss rate of the loess on China Loess Plateau was about 1×10^8 t·5a-1 in Pleistocene,today it isabout 14.4×10^8 t·a-1,and the Loess Plateau would disappear after66 000 to132 000 years if at this erosion rate.
出处
《中国沙漠》
CSCD
北大核心
2008年第2期195-201,共7页
Journal of Desert Research
基金
国家自然科学基金重点项目(40638038)资助
关键词
降尘量
空间分布
沙尘输送
黄土堆积
amount of dustfall
spatial distribution
dust transportation
loess accumulation
