Based on the macrofauna data(2008-2011) in Xiaoqing River estuary and its adjacent sea, Laizhou Bay of Bohai Sea, China, the AZTI Marine Biotic Index(AMBI) and Multivariate AMBI(M-AMBI) were used for benthic habitat q...Based on the macrofauna data(2008-2011) in Xiaoqing River estuary and its adjacent sea, Laizhou Bay of Bohai Sea, China, the AZTI Marine Biotic Index(AMBI) and Multivariate AMBI(M-AMBI) were used for benthic habitat quality(BHQ) assessment. Results showed that BHQ presented an obvious trend of improvement along the direction of stream channel and river mouth, and in the coastal areas. AMBI and M-AMBI were significantly related to environmental pressure gradient data. Therefore, the two indices can well indicate BHQ in the studied area. However, there were significant differences between results of the two indices. In the cases of low taxa number and high abundance of single species, AMBI might overestimate BHQ. We thus adjusted its thresholds to solve this problem. And M-AMBI might overestimate BHQ when benthic assemblage was dominated by the opportunistic species. Then we could raise the weight of AMBI in the calculation of M-AMBI to handle the problem.展开更多
Green fluorescent protein（GFP） plasmid was caged by 8-bromo-7-hydroxyquinolinyl chromophore（BHQ） for controlling its expression with exact spatiotemporal resolution.In vitro and in vivo experiments clearly verifie...Green fluorescent protein（GFP） plasmid was caged by 8-bromo-7-hydroxyquinolinyl chromophore（BHQ） for controlling its expression with exact spatiotemporal resolution.In vitro and in vivo experiments clearly verified that,comparing with Bhc caging, the expression level of caged GFP plasmid was dramatically decreased and then efficiently restored after subsequent photolysis.展开更多
通过对浙江余杭北湖桥钻孔(简称BHQ孔)沉积物中总有机碳(TOC)和碳同位素(δ^(13)C_(org))的分析,结合碳氮比(C/N)、粒度参数、年代和孢粉资料,探讨了研究区域早中全新世期间气候演变规律。结果表明,BHQ孔所在区域早中全新世期间,环境变...通过对浙江余杭北湖桥钻孔(简称BHQ孔)沉积物中总有机碳(TOC)和碳同位素(δ^(13)C_(org))的分析,结合碳氮比(C/N)、粒度参数、年代和孢粉资料,探讨了研究区域早中全新世期间气候演变规律。结果表明,BHQ孔所在区域早中全新世期间,环境变化可以划分为3段:111.4~8.7 ka B.P.,δ^(13)C_(org)在-27.24‰^-23.4‰范围内波动升高,TOC含量(0.19%~0.69%)呈显著增加趋势,指示气候由冷干逐渐转向温湿。2 8.7~8.0 ka B.P.,TOC含量偏低,δ^(13)C_(org)(-24.91‰^-22.93‰)较为偏正,指示气候呈冷干—温湿—温干。38.0~4.2 ka B.P.,TOC含量(0.18%~2.18%)和δ^(13)C_(org)(-26.33‰^-19.09‰)变化频繁且幅度较大,但整体上TOC含量偏高,δ^(13)C_(org)偏负,指示该段时期内气候总体呈暖湿特征,且存在不同尺度的冷暖波动。其中在8.0~5.7 ka B.P.期间,TOC含量(0.43%~2.18%)明显偏高,δ^(13)C_(org)(-25.79‰^-23.15‰)明显偏负,指示气候温暖湿润,对应于区域全新世大暖期;此外本段时期内还记录到5.5 ka B.P.和4.2 ka B.P.两次冷事件。由此表明湖沼相沉积物TOC及δ^(13)C_(org)可以记录降水量和温度的变化状况,能有效指示古气候的变化规律,同时研究结果初步揭示了浙北地区早中全新世期间气候演变特点。展开更多
基于浙江余杭北湖桥(简称BHQ)钻孔粒度相关参数和年代数据的分析,试图揭示浙江西北部地区早中全新世期间沉积环境演变的特征.结果表明:北湖草荡地区在早中全新世期间(约11363—4178 a BP),沉积物粒度组成以粉砂和粘土质粉砂互层分布为特...基于浙江余杭北湖桥(简称BHQ)钻孔粒度相关参数和年代数据的分析,试图揭示浙江西北部地区早中全新世期间沉积环境演变的特征.结果表明:北湖草荡地区在早中全新世期间(约11363—4178 a BP),沉积物粒度组成以粉砂和粘土质粉砂互层分布为特征,粉砂组分平均含量达到71.58%,粘土组分平均值为24.13%;在气候干湿波动的背景下,早中全新世期间研究区域的沉积环境并不稳定,湖泊水位波动频繁,沉积环境经历了低湖面时期、高湖面时期及过渡时期等演化阶段.展开更多
基金supported by the NSFC-Shandong Joint Fund for Marine Science Research Centers (Grant No. U1406404)the National Marine Public Welfare Research Project of China (Grant No. 201405007)
文摘Based on the macrofauna data(2008-2011) in Xiaoqing River estuary and its adjacent sea, Laizhou Bay of Bohai Sea, China, the AZTI Marine Biotic Index(AMBI) and Multivariate AMBI(M-AMBI) were used for benthic habitat quality(BHQ) assessment. Results showed that BHQ presented an obvious trend of improvement along the direction of stream channel and river mouth, and in the coastal areas. AMBI and M-AMBI were significantly related to environmental pressure gradient data. Therefore, the two indices can well indicate BHQ in the studied area. However, there were significant differences between results of the two indices. In the cases of low taxa number and high abundance of single species, AMBI might overestimate BHQ. We thus adjusted its thresholds to solve this problem. And M-AMBI might overestimate BHQ when benthic assemblage was dominated by the opportunistic species. Then we could raise the weight of AMBI in the calculation of M-AMBI to handle the problem.
基金supported by the National Natural Science Foundation of China(No90713009)
文摘Green fluorescent protein（GFP） plasmid was caged by 8-bromo-7-hydroxyquinolinyl chromophore（BHQ） for controlling its expression with exact spatiotemporal resolution.In vitro and in vivo experiments clearly verified that,comparing with Bhc caging, the expression level of caged GFP plasmid was dramatically decreased and then efficiently restored after subsequent photolysis.
文摘通过对浙江余杭北湖桥钻孔(简称BHQ孔)沉积物中总有机碳(TOC)和碳同位素(δ^(13)C_(org))的分析,结合碳氮比(C/N)、粒度参数、年代和孢粉资料,探讨了研究区域早中全新世期间气候演变规律。结果表明,BHQ孔所在区域早中全新世期间,环境变化可以划分为3段:111.4~8.7 ka B.P.,δ^(13)C_(org)在-27.24‰^-23.4‰范围内波动升高,TOC含量(0.19%~0.69%)呈显著增加趋势,指示气候由冷干逐渐转向温湿。2 8.7~8.0 ka B.P.,TOC含量偏低,δ^(13)C_(org)(-24.91‰^-22.93‰)较为偏正,指示气候呈冷干—温湿—温干。38.0~4.2 ka B.P.,TOC含量(0.18%~2.18%)和δ^(13)C_(org)(-26.33‰^-19.09‰)变化频繁且幅度较大,但整体上TOC含量偏高,δ^(13)C_(org)偏负,指示该段时期内气候总体呈暖湿特征,且存在不同尺度的冷暖波动。其中在8.0~5.7 ka B.P.期间,TOC含量(0.43%~2.18%)明显偏高,δ^(13)C_(org)(-25.79‰^-23.15‰)明显偏负,指示气候温暖湿润,对应于区域全新世大暖期;此外本段时期内还记录到5.5 ka B.P.和4.2 ka B.P.两次冷事件。由此表明湖沼相沉积物TOC及δ^(13)C_(org)可以记录降水量和温度的变化状况,能有效指示古气候的变化规律,同时研究结果初步揭示了浙北地区早中全新世期间气候演变特点。
文摘基于浙江余杭北湖桥(简称BHQ)钻孔粒度相关参数和年代数据的分析,试图揭示浙江西北部地区早中全新世期间沉积环境演变的特征.结果表明:北湖草荡地区在早中全新世期间(约11363—4178 a BP),沉积物粒度组成以粉砂和粘土质粉砂互层分布为特征,粉砂组分平均含量达到71.58%,粘土组分平均值为24.13%;在气候干湿波动的背景下,早中全新世期间研究区域的沉积环境并不稳定,湖泊水位波动频繁,沉积环境经历了低湖面时期、高湖面时期及过渡时期等演化阶段.
