Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 137Cs techniqu

来源 :Chinese Science Bulletin | 被引量 : 0次 | 上传用户:cmdl_CQ
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2 376.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5) suffered erosion only. By using 137Csmodel, the average wind erosion rates for shrub coppice dune The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2 376.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studying arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, ie the shrub coppicedunes (S1) and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition, while the grasslands (S4, S6 and S7) and dry farmlands (S5) reduced only. By using 137Csmodel, the average wind erosion rates for shrub coppice dune
其他文献
现在有些在黄河上工作的同志,看到下游修防工程大大的加强,又加这些同志常常听说,黄河的彻底治理必须从上游解决蓄水拦沙问题,因此他们便得出一条「结论」:「下游修防已到头
雕制红丝石砚的材料红丝石 ,产于山东青州的黑山和临朐县的老崖固 ,质量和数量以后者为最 ,因古代的临朐县归青州管辖 ,故红丝石砚又称青州红丝砚。追溯红丝砚的历史 ,早在晋
“礼仪”一直以来都与道德、法律和制度互为表里,深深维系着社会人伦道德观念,影响着人们生活的方方面面。本文通过对英国古典时代剧《唐顿庄园》的观察,来比较中英传统社会
这种防止谷壑冲蚀的方法,乌·姆·伯尔特克维赤作过详细的研究。1910年在波洛托夫斯克省开始采用,以后此法不仅在乌克兰得到了推广,并在森林草原地带及波窝洛日耶(伏尔加河
基于谱有限元法和模态展开法,针对各向异性薄板,建立激光激发Lamb波的数值模型,得到各向异性薄板中Lamb波沿不同方向传播的色散曲线及Lamb波的传播特性。数值模拟结果表明,谱
老乡们,同志们:黄河自七月一日起,进入大汛期,大家都很关心黄河的事,因此,我今天来和大家谈一谈黄河防汛的问题:大家都知道,防汛就是不护黄河开口子。为甚么不让黄河开口了
3月30日落幕的河南稀有剧种公益展演,18个难得一见的剧种在郑州集中亮相,稀罕、新鲜,是很多观众最直接的感受。大弦戏的惊悚,宛梆的呕音,柳琴戏的婉约,丝弦道的新奇,大平调的刚猛,都是人们所陌生的……  往常,提到河南的戏曲,很多人首先想到的是豫剧、曲剧、越调这三大剧种。其实,在河南还有不少流布区域较窄、观众和从业人员较少的稀有剧种,它们同样承载着一个地方的文化记忆和文化基因,映射着当地的风土人情。
《唐顿庄园》的热播,为全世界观众展现了英国贵族家庭中独特的“楼上楼下”式的主仆关系结构。本文通过对剧中情节分析总结出这一主仆关系的特点,并深入分析这种关系背后的制
本省防汛工作检查组七月八日到达聊城,参加了聊城地委的防汛工作会议。之后。检查了寿张、范县的防汛滞洪工作,实地视察了一部堤防险工。十七日转赴菏泽,首先听取了该专区黄
2016年9月30日,时值10·5中国船员金三角遇害事件五周年到来之际,影片湄公河行动在国内各大院线上映,亦是国庆66周年献礼影片之一。截止到10月14日,上映两周票房突破81008万,