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Glycerol Dialkyl Glycerol Tetraethers (GDGTs) serve as important tools for the quantitative reconstruction of paleoclimate and paleoecology in both continental and marine environments. Previous studies of GDGTs in the terrestrial environments focused primarily on the soils from the relatively warm-humid or cold-dry regions. However, it is still unclear how GDGTs respond to environmental variables in the cold-humid regions. Here, we collected soils along an altitudinal transect of Mountain (Mt.) Changbai, which has a typical cold-humid climate, to investigate the distribution of GDGTs and the response of GDGT-based proxies to changes in climate along the transect. The shift in the distribution of archaeal isoprenoidal GDGTs (isoGDGTs) revealed that the archaeal community varied significantly along the transect, which can affect the relationship between TEX86 and mean annual air temperature (MAT). In addition, the increased temperature seasonality at higher altitudes exerted a significant impact on TEX86. We proposed a global calibration of TEX86 for the growing season temperature reconstruction in the soil environments: T =85.19×TEX86− 46.30 ( R 2=0.84, p 0.55 are diagnostic for the cold-humid climate. Thus, the combination of MBT′5me and MBT′6me has the potential as a tool for the identification of different types of paleoclimate.

Five chemical and four non-chemical presowing treatments were tested on seeds of three conifers (Larix principis-rupprechtii Mayr, Pinus sylvestris L. var. mongolica Litv, and Pinus tabulaeformis Carr.). By itself, cold stratification with snow for 60 days did not significantly improve the germination percentage over that of soaking the seed in warm water (45 °C) for 12 hours. However, including either one or two dehydration-rehydration cycles after the cold stratification did improve both the percentage and speed of germination of seed from all three species. Soaking seed for 12 hours in various chemicals (KNO3, CaCl2, CuSO4, KMnO4 and GA3) before germination was less effective than the snow stratification followed by double dehydration-rehydration treatments (Chang and Lin, 1989).

We identify a shock-induced melting and great facilities of the melting in accelerating subsequent alloying reactions in nanostructured Ni/Al multilayer films using a novel molecular dynamics technique, which captures the initial shock transit as well as the subsequent long time scale alloying process. We observe a pronounced increase of the pressure in the melting process (i.e., a process of coexistence of solid and liquid phases). As soon as the melting completes, the temperature increases dramatically indicating a start of explosive alloying reactions and the pressure starts to decrease. The pressure going up or down is determined by the competition between melting and alloying reactions.