检索条件"作者=WANG Ninglian Key Laboratory of Cryosphere and Environment, cold and arid {2. {3. and engineering research Institute, chinese academy of sciences, Lanzhou 73.00, china"
Snowpacks samples were colleted from two glaciers: Baishui No.1 glacier and Hailuogou No.1 glacier in June, 2.06. The method of sea-salt ions tracer, correlation analysis and trend analysis were used in this research...
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Snowpacks samples were colleted from two glaciers: Baishui No.1 glacier and Hailuogou No.1 glacier in June, 2.06. The method of sea-salt ions tracer, correlation analysis and trend analysis were used in this research in order to confirm the source of main ions, it is indicated that Na^+ is mainly from marine moisture and other ions mainly originate from land dust. The non-marine source percent of Cl^-, NO3.- , SO4^2., K^+, Ca^2. and Mg^2. is 52., 99%, 100%, 98%, 99.9% and 83., respectively, in Hailuogou No.1 glacier, while the corresponding value in Baishui No.1 glacier is 68%, 99%, 100%, 98%, 99% and 59%. The non-marine source of ions is from dust of Central Asia arid regions carried by westerly circulation and the plateau borne-areas with Qinghai-Tibet Plateau winter monsoon in two glacial areas. However, the import of local dust in glacial area has made a great contribution to ions concentration in Baishui No.1 glacier, which accounts for the reason why the ions concentration in Baishui No.1 glacier is much higher than that of Hailuogou No.1 glacier. It is obvious that the source of each ion is different between Hailuogou No.1 glacier and Baishui No.1 glacier. There are three reasons which can explain it: firstly, the difference in the internal {2. of glacial area, such as lithology, mountain-valley wind system, topographical relief and so on; secondly, the influence exerted by ions elution in snowpacks section, and ions elution in Hailuogou No.1 glacier is very strong; and thirdly, the difference caused due to varying ions transporting styles, deposition modes, chemical characteristics and post-ions-deposition process.
In the reconstruction of past climate using stable carbon isotope composition (δ13.) in tree ring,the responses of the stable carbon composition (δ13.) of multiple tree species to environmental factors must be known...
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In the reconstruction of past climate using stable carbon isotope composition (δ13.) in tree ring,the responses of the stable carbon composition (δ13.) of multiple tree species to environmental factors must be known detailedly. This study presented two δ13. series in annual tree rings for chinese hem-lock (Tsuga chinensis Pritz) and alpine pine (Pinus densata Mast),and investigated the relationships between climatic parameters and stable carbon discrimination (△13.) series,and evaluated the poten-tial of climatic reconstruction using △13. in both species,in a temperate-moist region of Chuanxi Pla-teau,{2.. The raw δ13. series of the two species was inconsistent,which may be a result of different responses caused by tree's inherent physiological differences. After removing the low-frequency ef-fects of CO2.concentration,the high-frequency (year-to-year) inter-series correlation of △13. was strong,indicating that △13. of the two tree species were controlled by common environmental conditions. The △13. series of the species were most significantly correlated with temperature and moisture stress,but in different periods and intensity between the species. During the physiological year,the impacts of temperature and moisture stress on △13. occur earlier for chinese hemlock (previous December to February for moisture stress and February to April for temperature,respectively) than for alpine pine (March to May for moisture stress and April to July for temperature,respectively). In addition,in temperate-moist regions,the control on △13. of single climatic parameter was not strongly dominant and the op-timal multiple regressions functions just explained the 3..5% variance of the total. Therefore,there is limited potential for using δ13. alone to identify clear,reliable climatic signals from two species.
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