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2005年5月25日,中国最大的民间科学探险组织——中国科学探险协会在北京召开新闻发布会,宣布第一支中国科考队即将于8月2日出发,前往东非大裂谷进行为期15天的科学考察。这次活动不仅得到中国有关政府部门、机构的支持和关注,也得到了埃塞俄比亚政府的热情支持,埃塞俄比亚驻华公使亲自为中国科考队出谋划策。科考队的组建和考察工作,由中国原创的高档探索发现视觉杂志《DEEP中国科学探险》杂志社具体承办。 相似文献
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本文从五个方面分析了孟尼利克二世在埃塞俄比亚抗意卫国战争中的作用 :1、消除国内封建割据 ,奠定举国团结御侮的基础 ;2、锐意推进近代化改革 ,增强了抵御侵略 ,维护独立的综合国力 ;3、坚决回击侵略者的无餍欲望 ,号召进行全民族的抗战 ;4、利用列强矛盾 ,争取法俄支持 ,改善国际地位 ;5、实施灵活的战略战术 ,诱敌深入 ,各个击破 ,打败侵略者 相似文献
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Foliar δ^13C and δ^15N values of C3 plants in the Ethiopia Rift Valley and their environmental controls 总被引:1,自引:0,他引:1
LIU XiaoHong ZHAO LiangJu GASAW Menassie GAO DengYi QIN DaHe REN JiaWen 《科学通报(英文版)》2007,52(9):1265-1273
The foliar C and N stable isotopic compositions (δ^13C and δ^15N) and the relationships between these compositions and environmental factors of C3 plants in the Ethiopia Rift Valley were investigated. There were three distribution patterns for foliar δ^13C with mean values of -26.7‰±0.4‰, -29.7‰ ±0.6‰ , and -26.9‰± 1.2‰ in cold-moist, temperate-moist, and arid-hot environments, respectively. The δ^15N values ranged from -1.4‰ ±1.7‰ to 14.3‰ ± 0.1‰, with higher values under arid-hot conditions and the lowest values in plants growing at higher altitudes under cold-moist conditions. A strong negative relationship between mean annual precipitation and δ^15N explained more than half of the observed variation in the δ^15N values (r2= 0.54, P 〈 0.001); a modest positive relationship was also found between δ^15N and temperature (r2 = 0.32, P 〈 0.01). A weakly positive relationship existed between δ^13C and temperature, and changes in δ^13C values with precipitation and altitude followed quadratic curves. This suggests a shift in the effects of water and heat conditions caused by altitude on carbon isotopic discrimination. 相似文献