Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The anal...Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.展开更多
The 1990 International Trans-Antarctica Expedition covered a total distance of 5 896 km and lasted 220 days, during the traverse the author carried out observations of snow-pit stratigraphyand surface characteristics ...The 1990 International Trans-Antarctica Expedition covered a total distance of 5 896 km and lasted 220 days, during the traverse the author carried out observations of snow-pit stratigraphyand surface characteristics along the Trans-Antarctica route and analyses of stable isotope and glaciochemistry of the selected samples. These studies have provided a batch of the latest and extensive data on the present climate and environment in the Antarctica, which is of great significance to the global change research. From the analysis of this batch of data, a group of achievements have been gained,which are helpful to our understanding comprehensively and systematically on the surface topography of Antarctic Ice Sheet, precipitation distribution, temperature difference, snowfall deposition processes,stable isotope distribution, distribution of main anions and canons and heavy-metal element and their sources in main geographic regions of the Antarctica.The stratigraphy profiles of total 106 snow-pits showed that in West Antarctica the meltwater infiltration-congelation is obvious and the annual precipitation is larger than that in East Antarctica, which implies that the climate in West Antarctica is warmer, more humid and influenced more greatly by the South Ocean than that in East Antarctica. Radiation ice-glazes found frequently in snow profiles indicate that even in inland of East Antarctica, surface 'melting' occurs in summer due to the long-time solar radiation.The distribution of δD in the surface 25 cm snow along the traverse showed that the δD decreases in general with increasing latitudes, and the minimum value occurs between 80° S and 85° S (around the Vostok Station). In the top area of the East Antarctic Plateau, ex d value is higher to other regions by 40%, which is tentatively attributed to the difference in vapor sources.The distribution of NO, along the traverse demonstrates a general feature of higher concentration in the inland than in the outer regions, but the NO3 flux is lower in inland region tha展开更多
基金This work was supported by the Knowledge Innovation Project of South China Insitute of Oceanology (Grant No. 5210607)Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KZCX2-108)the National Natural Science Foundation of C
文摘Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.
文摘The 1990 International Trans-Antarctica Expedition covered a total distance of 5 896 km and lasted 220 days, during the traverse the author carried out observations of snow-pit stratigraphyand surface characteristics along the Trans-Antarctica route and analyses of stable isotope and glaciochemistry of the selected samples. These studies have provided a batch of the latest and extensive data on the present climate and environment in the Antarctica, which is of great significance to the global change research. From the analysis of this batch of data, a group of achievements have been gained,which are helpful to our understanding comprehensively and systematically on the surface topography of Antarctic Ice Sheet, precipitation distribution, temperature difference, snowfall deposition processes,stable isotope distribution, distribution of main anions and canons and heavy-metal element and their sources in main geographic regions of the Antarctica.The stratigraphy profiles of total 106 snow-pits showed that in West Antarctica the meltwater infiltration-congelation is obvious and the annual precipitation is larger than that in East Antarctica, which implies that the climate in West Antarctica is warmer, more humid and influenced more greatly by the South Ocean than that in East Antarctica. Radiation ice-glazes found frequently in snow profiles indicate that even in inland of East Antarctica, surface 'melting' occurs in summer due to the long-time solar radiation.The distribution of δD in the surface 25 cm snow along the traverse showed that the δD decreases in general with increasing latitudes, and the minimum value occurs between 80° S and 85° S (around the Vostok Station). In the top area of the East Antarctic Plateau, ex d value is higher to other regions by 40%, which is tentatively attributed to the difference in vapor sources.The distribution of NO, along the traverse demonstrates a general feature of higher concentration in the inland than in the outer regions, but the NO3 flux is lower in inland region tha
