中更新世气候转型以来,南极冰盖对全球气候的影响作用逐渐放大。西南极冰盖以海洋冰盖为主体,稳定性差,冰架前缘沉积模式复杂,对于冰期-间冰期气候旋回变化十分敏感。因此,文章通过对中国第31次南极考察在罗斯海扇区北维多利亚地岸外钻...中更新世气候转型以来,南极冰盖对全球气候的影响作用逐渐放大。西南极冰盖以海洋冰盖为主体,稳定性差,冰架前缘沉积模式复杂,对于冰期-间冰期气候旋回变化十分敏感。因此,文章通过对中国第31次南极考察在罗斯海扇区北维多利亚地岸外钻取长度达412 cm的ANT31-R22岩芯(173.152°E,67.215°S;水深2906 m)的浮游有孔虫Nps-δ^(18)O、冰筏碎屑含量及其岩矿组成分析等研究,重建了罗斯海扇区22.8~534.0 ka B.P.期间的冰筏碎屑沉积物源和周边冰架的演化历史。R22岩芯的岩矿组合显示:MIS13期晚期至MIS7期,横贯山脉-维多利亚地的Ferrar组基性火成岩是罗斯海扇区的主要物源;MIS7期之后横贯山脉-维多利亚地物源输入明显下降,花岗岩和变质岩的输入有所增加,推测马利伯德地花岗岩-变质岩物源区输入增加,西南极冰盖对于罗斯海扇区的影响逐渐增强。同时,综合对比多个太平洋扇区岩芯/站位的冰筏碎屑指标显示:自晚更新世以来,罗斯海扇区至阿蒙森海扇区的深海冰筏碎屑沉积集中出现在冰盛期-冰消期阶段,是气候回升过程中西南极高纬地区冰架消融的重要标志,而中高纬地区的冰筏碎屑沉积更可能是冰盛期的标志。展开更多
Wild populations of Chlamys farreri derived from Japan and China are used as parents in a cross breeding experiment conducted in Zhangzi Island of Liaoning Province in the early May of 2000. Four different first filia...Wild populations of Chlamys farreri derived from Japan and China are used as parents in a cross breeding experiment conducted in Zhangzi Island of Liaoning Province in the early May of 2000. Four different first filial generations of the crossbreeding, namely JC, CJ, CC and JJ, which represent different cross combinations of the parents, are differentiated from each other in some observed quantitative traits including survival rate, hatchery rate and attachment rate, etc. By ANOVA analysis, significant differences in growth rate are found among the four populations of the offspring after one year of culturing in Shandong Province. JJ population shows the fastest growth rate and has shell height of 46.1±0.71(SD)mm in average, whereas the other three populations, CC, CJ and JC, has the shell height of 43.1±0.42mm, 41.5±0.48mm and 37.2 ±0.31mm, respectively. No heterosis is detected in the experiment.展开更多
文摘中更新世气候转型以来,南极冰盖对全球气候的影响作用逐渐放大。西南极冰盖以海洋冰盖为主体,稳定性差,冰架前缘沉积模式复杂,对于冰期-间冰期气候旋回变化十分敏感。因此,文章通过对中国第31次南极考察在罗斯海扇区北维多利亚地岸外钻取长度达412 cm的ANT31-R22岩芯(173.152°E,67.215°S;水深2906 m)的浮游有孔虫Nps-δ^(18)O、冰筏碎屑含量及其岩矿组成分析等研究,重建了罗斯海扇区22.8~534.0 ka B.P.期间的冰筏碎屑沉积物源和周边冰架的演化历史。R22岩芯的岩矿组合显示:MIS13期晚期至MIS7期,横贯山脉-维多利亚地的Ferrar组基性火成岩是罗斯海扇区的主要物源;MIS7期之后横贯山脉-维多利亚地物源输入明显下降,花岗岩和变质岩的输入有所增加,推测马利伯德地花岗岩-变质岩物源区输入增加,西南极冰盖对于罗斯海扇区的影响逐渐增强。同时,综合对比多个太平洋扇区岩芯/站位的冰筏碎屑指标显示:自晚更新世以来,罗斯海扇区至阿蒙森海扇区的深海冰筏碎屑沉积集中出现在冰盛期-冰消期阶段,是气候回升过程中西南极高纬地区冰架消融的重要标志,而中高纬地区的冰筏碎屑沉积更可能是冰盛期的标志。
文摘Wild populations of Chlamys farreri derived from Japan and China are used as parents in a cross breeding experiment conducted in Zhangzi Island of Liaoning Province in the early May of 2000. Four different first filial generations of the crossbreeding, namely JC, CJ, CC and JJ, which represent different cross combinations of the parents, are differentiated from each other in some observed quantitative traits including survival rate, hatchery rate and attachment rate, etc. By ANOVA analysis, significant differences in growth rate are found among the four populations of the offspring after one year of culturing in Shandong Province. JJ population shows the fastest growth rate and has shell height of 46.1±0.71(SD)mm in average, whereas the other three populations, CC, CJ and JC, has the shell height of 43.1±0.42mm, 41.5±0.48mm and 37.2 ±0.31mm, respectively. No heterosis is detected in the experiment.
