摘要
对青藏高原祁连山老虎沟12号冰川、唐古拉山小冬克玛底冰川及珠穆朗玛峰北坡东绒布冰川雪坑样品中可溶性有机碳(DOC)和主要离子的质量浓度进行了分析.结果表明3个雪坑中DOC的平均质量浓度分别为(250.30±157.10)、(216.92±142.82)和(152.50±56.11)μg·L-1,具有从北到南依次减小的空间分布特点.3个雪坑DOC和主要离子质量浓度比例分析表明,唐古拉山冰川区和珠穆朗玛峰冰川区两个雪坑中DOC质量浓度与主要离子总质量浓度相当(DOC质量浓度占DOC与主要离子总质量浓度的比例分别为51%和49%).相应地,祁连山冰川区雪坑由于地理位置和气候条件等因素,受粉尘影响较大,导致Ca2+的质量浓度最高可达5 299.18μg·L-1,DOC所占比例较低(仅占5%).青藏高原冰川区DOC与Ca2+、Mg2+、K+和SO2-4均呈显著正相关.主成分分析(PCA)表明,青藏高原冰川区雪坑DOC主要是自然来源,也有生物质、化石燃料燃烧和农业生产过程等人为排放的贡献.此外,对3个雪坑的碳沉降通量进行了估算,LHG、TGL和ZF这3个雪坑的碳沉降通量分别为189.23、132.76和128.44 mg·(m2·a)-1,这对该地区碳循环的深入认识和研究具有重要意义,同时也有利于冰川变化的研究.
Snowpit samples of three glaciers( Laohugou NO. 12 Glacier( LHG),Small Dongkemadi Glacier on Mount Tanggula( TGL) and East Rongbuk Glacier on Mount Everest( ZF)) in the Tibetan Plateau were collected. Concentrations of DOC and major ions were analyzed. The results showed that average DOC concentrations of the snowpits of LHG,TGL and ZF were( 250. 30 ±157. 10),( 216. 92 ± 142. 82) and( 152. 50 ± 56. 11) μg·L-1,respectively. DOC of TGL and ZF accounted for large parts of total values of DOC and ions. Correspondingly,DOC of LHG accounted for small part( only 5%),because LHG was located at north China and intensively influenced by natural mineral dust,which caused high concentrations of Ca2 +( the highest value could reach 5 299. 18μg·L-1) and consequently low percentage of DOC of snowpit samples. Correlation and PCA analyses were used to study the sources of DOC. DOC was significantly correlated with Ca2 +,Mg2 +,K+and SO2-4. Additionally,PCA further indicated that the main potential source of DOC was the natural source of mineral dust. Meanwhile,anthropogenic pollutants( e. g. biomass,fossil combustion and agricultural related pollutants) could also not be ignored. Moreover,the carbon depositional fluxes of three snowpits were roughly estimated,and the values of LHG,TGL and ZF snowpits were 189. 23,132. 76 and 128. 44 mg·( m2·a)-1,respectively,which played a significant role in the carbon cycle in this region and was also helpful for the study of glaciers fluctuation.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2015年第8期2827-2832,共6页
Environmental Science
基金
国家自然科学基金项目(41271015
41171398)
冰冻圈科学国家重点实验室项目(SKLCS-ZZ-2008-01)
