Ping Gong ^a, Xiao-ping Wang ^{a, *}, Sheng-hai Li ^a, Wu-sheng Yu ^a, Jiu-le Li ^a,Dambaru Ballab Kattel ^{a, c}, Wei-cai Wang ^a, Lochan Prasad Devkota ^b, Tan-dong Yao ^a,Daniel R. Joswiak ^a

 

a Key Laboratory of Tibetan Environmental Changes and Land Surface Process, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100101, China

b Central Department of Hydrology and Meteorology, Tribhuvan University, Kathmandu 44618, Nepal

c Department of Meteorology, COMSATS Institute of Information Technology, Islamabad, Pakistan

 

 

Abstract：Studies have been devoted to the transport and accumulation of persistent organic pollutants (POPs) in mountain environments. The Himalayas have the widest altitude gradient of any mountain range, but few studies examining the environmental behavior of POPs have been performed in the Himalayas. In this study, air, soil, and leaf samples were collected along a transect on the southern slope of the Himalayas, Nepal (altitude: 135e5100 m). Local emission occurred in the lowlands, and POPs were transported by uplift along the slope. During the atmospheric transport, the HCB proportion increased from the lowlands (20%) to high elevation (>50%), whereas the proportions of DDTs decreased. The

largest residue of soil POPs appeared at an altitude of approximately 2500 m, and may be related to absorption by vegetation and precipitation. The net deposition tendencies at the airesoil surface indicated that the Himalayas may be a ‘sink’ for DDTs and PCBs.

 

  Persistent organic pollutants (POPs)

  Altitudinal distribution

  Hierarchical clustering analysis (HCA)

  Cold-trapping

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