青藏高原冰川雪细菌与气候环境的关系

通过荧光显微镜测定细菌密度，利用DGGE图谱和Shannon-Weaver指数分析细菌种类多样性，对青藏高原北部老虎沟12号冰川、南部东绒布冰川和东南部海螺沟2号冰川雪坑的细菌密度和种类多样性做了差异性分析. 结果表明:老虎沟12号冰川雪坑细菌密度平均值比东绒布冰川和海螺沟2号冰川高，老虎沟12号冰川雪坑细菌种类多样性比东绒布冰川高，这与高原南、北部不同大气环流引起的大气微粒含量的差异性有关. 海螺沟2号冰川雪坑细菌种类多样性均最高，与该冰川所受的大气环流多样性最高相一致. 东绒布冰川雪坑细菌密度平均值与南极点相近，与其远离人类污染，因而大气环境本底值低有关. 海拔高的东绒布冰川雪坑细菌密度和种类多样性均比海拔低的海螺沟2号冰川和老虎沟12号冰川低，即二者与海拔高度呈反比. 

Relation between Bacteria in Glacial Snow with Climate and Environment in the Tibetan Plateau

Density and species diversity of bacteria were investigated respectively by epifluorescence microscope, DGGE analysis and Shannon-Weaver index, with snow pit samples from southern part of East Rongbuk (ER) Glacier, northern part of Laohugou Glacier and southeastern part of Hailuogou Glacier in the Tibetan Plateau. According to the results, bacterial density in the snow pit of Laohugou Glacier is higher than that in ER Glacier and Hailuogou Glacier. Species diversity of bacteria in Laohugou Glacier is higher than that in ER Glacier. Continental dust originated from the Northwest China accounts for higher density and species diversity of bacteria in the northern Tibetan Plateau, whilemonsoon moisture exerts great influence on bacteria with low abundance and species diversity in the southern and southeastern plateau. Hailuogou Glacier is thehighest in species diversity of bacteria, which is consistent to their most kind of derivation from atmospheric circulations. Bacterial density in ER Glacier is very close to that in south pole of Antarctica, which confirmed that Himalayas provides a very low background in atmospheric environment. Density and species diversity of bacteria in ER Glacier with higher altitude are much lower than that in Laohugou Glacier and Hailuogou Glacier with lower altitude, showing their inverse proportion with the altitude.