In China, accelerating industrialization and urbanization followinghigh-speed economic development and population increases have greatly impacted land use/coverchanges, making it imperative to obtain accurate and up t...In China, accelerating industrialization and urbanization followinghigh-speed economic development and population increases have greatly impacted land use/coverchanges, making it imperative to obtain accurate and up to date iufbimation on changes soas toevaluate their environmental effects. The major purpose of this study was to develop a new method tofuse lower spatial resolution multispectral satellite images with higher spatial resolutionpanchromatic ones to assist in land use/cover mapping.An algorithm of a new fusion method known asedge enhancement intensity modulation (EEIM) was proposed to merge two optical image data sets ofdifferent spectral ranges. The results showed that the EEIM image was quite similar in color tolower resolution multispectral images, and the fused product was better able to preserve spectralinformation. Thus, compared to conventional approaches, the spectral distortion of the fused imageswas markedly reduced. Therefore, the EEIM fusion method could be utilized to fuse remote sensingdata from the same or different sensors, including TM images and SPOT5 panchromatic images,providing high quality land use/cover images.展开更多
By using a degree-day based distributed hydrological model, regimes of glacial runoff from the Koxkar glacier during 2007-2011 are simulated, and variations and characteristics of major hydrological components are dis...By using a degree-day based distributed hydrological model, regimes of glacial runoff from the Koxkar glacier during 2007-2011 are simulated, and variations and characteristics of major hydrological components are discussed. The results show that the meltwater runoff contributes 67.4%, of the proglacial discharge, out of which snowmelt, clean ice melting, buried-ice ablation and ice-cliff backwasting account for 22.4%, 21.9%, 17.9% and 5.3% of the total melt runoff, respectively. Rainfall runoff is significant in mid-latitude glacierized mountain areas like Tianshan and Karakorum. In the Koxkar glacier catchment, about 11.5% of stream water is initiated from liquid precipitation. Spatial distributions for each glacial runoff component reveal the importance of climatic gradients, local topography and morphology on glacial runoff generation, and temporal variations of these components is closely related to the annual cycle of catchment meteorology and glacier storage. Four stages are recognized in the seasonal variations of glacier storage, reflecting changes in meltwater yields, meteorological conditions and drainage systems in the annual hydrological cycle.展开更多
基金Project supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX3-SW-427), the National Key Basic Research Support Foundation of China (NKBRSF) (No. 2002CB410810) and the China Scholarship Council (No. 2003836044).
文摘In China, accelerating industrialization and urbanization followinghigh-speed economic development and population increases have greatly impacted land use/coverchanges, making it imperative to obtain accurate and up to date iufbimation on changes soas toevaluate their environmental effects. The major purpose of this study was to develop a new method tofuse lower spatial resolution multispectral satellite images with higher spatial resolutionpanchromatic ones to assist in land use/cover mapping.An algorithm of a new fusion method known asedge enhancement intensity modulation (EEIM) was proposed to merge two optical image data sets ofdifferent spectral ranges. The results showed that the EEIM image was quite similar in color tolower resolution multispectral images, and the fused product was better able to preserve spectralinformation. Thus, compared to conventional approaches, the spectral distortion of the fused imageswas markedly reduced. Therefore, the EEIM fusion method could be utilized to fuse remote sensingdata from the same or different sensors, including TM images and SPOT5 panchromatic images,providing high quality land use/cover images.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences under Grant No. KZCX2-YW-GJ04National Nature Science Foundation of China (NSFC) under Grant Nos. 41130641 and 41271078
文摘By using a degree-day based distributed hydrological model, regimes of glacial runoff from the Koxkar glacier during 2007-2011 are simulated, and variations and characteristics of major hydrological components are discussed. The results show that the meltwater runoff contributes 67.4%, of the proglacial discharge, out of which snowmelt, clean ice melting, buried-ice ablation and ice-cliff backwasting account for 22.4%, 21.9%, 17.9% and 5.3% of the total melt runoff, respectively. Rainfall runoff is significant in mid-latitude glacierized mountain areas like Tianshan and Karakorum. In the Koxkar glacier catchment, about 11.5% of stream water is initiated from liquid precipitation. Spatial distributions for each glacial runoff component reveal the importance of climatic gradients, local topography and morphology on glacial runoff generation, and temporal variations of these components is closely related to the annual cycle of catchment meteorology and glacier storage. Four stages are recognized in the seasonal variations of glacier storage, reflecting changes in meltwater yields, meteorological conditions and drainage systems in the annual hydrological cycle.
