摘要
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
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 (S1), semi-fixed dune fields (S3),ry farmlands (S5) and grasslands (S4, S6 and S7) were estimated to be 84.14, 69.43, 30.68 and21.84 t · ha-1 · a-1 respectively, averaging 47.59 t ?ha 1 ?a 1 for the whole plateau, which can beregarded as of the medium erosion standard. These results derived from 137Cs for the first timehave significant implications for the further research of wind erosion and desertification control inthe Qinghai-Tibetan Plateau.
作者
YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of China, Beijing Normal University, Beijing 100875, China
2. Institute of Desert Research, Chinese Academy of Sciences, Lanzhou 730000, China
3. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
4. Department of Physics, Sichuan Union University, Chengdu 610041, China
