High-resolution Chirp profiling and coring reveals an elongated （ca. 400 km） Holocene Zhujiang River （Pearl River）-derived mud area （maximum thickness 〉 20 m） extending from the Zhujiang River Delta, southwest-...High-resolution Chirp profiling and coring reveals an elongated （ca. 400 km） Holocene Zhujiang River （Pearl River）-derived mud area （maximum thickness 〉 20 m） extending from the Zhujiang River Delta, southwest-ward off the Guangdong coast, to the Leizhou Peninsula. Two depo-centers, one proximal and one distal, are identified. On the continental shelf off the west Guangdong Province, the mud is deposited in water depth shallower than 50 m; while to the southeast of the Zhujiang River Estuary, the mud area can extend to the -120 m isobath. A combined analysis with the stratigraphic sequences of other muddy deposits in the West-ern Pacific marginal seas （mainly Changjiang （Yangtze） and Huanghe （Yellow） Rivers derived） indicates that the initiation of the Zhujiang River muddy deposit can be further divided into two stages： Stage 1 is before the mid-Holocene sea-level highstand （ca. 7.0 cal. ka BP）, the proximal mud was mostly deposited after 9.0 cal. ka BP, when the sea-level rose slowly after the Meltwater Pulse -1C; Stage 2, after the mid-Holocene sea-level highstand, clinoform developed on the continental shelf off the west Guangdong Province, extending ca. 400 km from the Zhujiang River Estuary. The proximal clinoform thins offshore, from ca. 10 m thickness around 5-10 m water depth to less than 1-2 m around 20-30 m water depth. In addition, we also find a de-veloped distal clinoform in the east of the Leizhou Peninsula.展开更多
在治理农村环境过程中常存在取样难、分析成本高、检测时间缓慢、污染情况复杂等问题,尤其是对城中村河道中元素的检测,为实现样品合理、快速地检测分析,研究了取样技术、消解方式、酸用量、酸度、消解效率对测定结果的影响,以抓斗式设...在治理农村环境过程中常存在取样难、分析成本高、检测时间缓慢、污染情况复杂等问题,尤其是对城中村河道中元素的检测,为实现样品合理、快速地检测分析,研究了取样技术、消解方式、酸用量、酸度、消解效率对测定结果的影响,以抓斗式设备为采样工具,经振荡、干燥,6m L HF+2m L HNO_(3)为提取试剂,采用石墨消解仪(200°C,30min)进行样品前处理,采用电感耦合等元素离子体光谱法进行检测,建立了快速石墨消解-电感耦合等离子光谱法同时测定城中村河道土壤中K、Na、Ca、Mg元素的方法。研究结果表明,在仪器最佳测试条件下,K、Na、Ca、Mg元素的检出限分别为2.08mg·kg^(-1)、2.63mg·kg^(-1)、1.26mg·kg^(-1)、1.09mg·kg^(-1),相对标准偏差为0.89%、2.90%、1.73%、6.19%。本方法所用试剂以化学纯为主,成本低,前处理时间短,高效快速,结果可靠,适用于城中村河道土壤中K、Na、Ca、Mg元素的快速检测。展开更多
基金The National Natural Science Foundation of China under contract Nos 41106045 and 41206045the Scientific Research Fund of the Second Institute of Oceanography,SOA under contract No.JT1102the Basic Research Fund of State Oceanic Administration(named as Pale-oceanographic Research in the Western Pacific)
文摘High-resolution Chirp profiling and coring reveals an elongated （ca. 400 km） Holocene Zhujiang River （Pearl River）-derived mud area （maximum thickness 〉 20 m） extending from the Zhujiang River Delta, southwest-ward off the Guangdong coast, to the Leizhou Peninsula. Two depo-centers, one proximal and one distal, are identified. On the continental shelf off the west Guangdong Province, the mud is deposited in water depth shallower than 50 m; while to the southeast of the Zhujiang River Estuary, the mud area can extend to the -120 m isobath. A combined analysis with the stratigraphic sequences of other muddy deposits in the West-ern Pacific marginal seas （mainly Changjiang （Yangtze） and Huanghe （Yellow） Rivers derived） indicates that the initiation of the Zhujiang River muddy deposit can be further divided into two stages： Stage 1 is before the mid-Holocene sea-level highstand （ca. 7.0 cal. ka BP）, the proximal mud was mostly deposited after 9.0 cal. ka BP, when the sea-level rose slowly after the Meltwater Pulse -1C; Stage 2, after the mid-Holocene sea-level highstand, clinoform developed on the continental shelf off the west Guangdong Province, extending ca. 400 km from the Zhujiang River Estuary. The proximal clinoform thins offshore, from ca. 10 m thickness around 5-10 m water depth to less than 1-2 m around 20-30 m water depth. In addition, we also find a de-veloped distal clinoform in the east of the Leizhou Peninsula.
文摘在治理农村环境过程中常存在取样难、分析成本高、检测时间缓慢、污染情况复杂等问题,尤其是对城中村河道中元素的检测,为实现样品合理、快速地检测分析,研究了取样技术、消解方式、酸用量、酸度、消解效率对测定结果的影响,以抓斗式设备为采样工具,经振荡、干燥,6m L HF+2m L HNO_(3)为提取试剂,采用石墨消解仪(200°C,30min)进行样品前处理,采用电感耦合等元素离子体光谱法进行检测,建立了快速石墨消解-电感耦合等离子光谱法同时测定城中村河道土壤中K、Na、Ca、Mg元素的方法。研究结果表明,在仪器最佳测试条件下,K、Na、Ca、Mg元素的检出限分别为2.08mg·kg^(-1)、2.63mg·kg^(-1)、1.26mg·kg^(-1)、1.09mg·kg^(-1),相对标准偏差为0.89%、2.90%、1.73%、6.19%。本方法所用试剂以化学纯为主,成本低,前处理时间短,高效快速,结果可靠,适用于城中村河道土壤中K、Na、Ca、Mg元素的快速检测。
