地磁暴发生时,电离层会有偏离平均水平的强烈扰动.基于全球电离层TEC及其时间变化率ROTI(Rate of TEC Index)数据,对2014年8月一次中等强度磁暴期间的全球电离层影响进行了分析,探讨了磁暴所引发电离层暴的可能机制.研究发现,本次磁暴...地磁暴发生时,电离层会有偏离平均水平的强烈扰动.基于全球电离层TEC及其时间变化率ROTI(Rate of TEC Index)数据,对2014年8月一次中等强度磁暴期间的全球电离层影响进行了分析,探讨了磁暴所引发电离层暴的可能机制.研究发现,本次磁暴伴随有明显的电离层暴效应.磁暴期间:南半球电离层以正相暴为主,北半球电离层暴则整体表现为短暂正相暴后长时间强的负相暴;电离层在北半球的下降比南半球强,并且这种下降持续了约一周时间;低纬区域电离层变化幅度明显小于中纬区域,高纬区域则主要表现为负暴效应;赤道北驼峰出现了明显的南移现象,直至磁赤道两侧双驼峰结构消失.对磁暴期间三个不同扇区的电离层ROTI变化的分析表明:欧洲—非洲扇区磁暴前有电离层闪烁发生,磁暴发生后消失,而东亚—澳大利亚及美洲扇区则无此现象出现.研究结果表明,此次磁暴期间的电离层变化存在明显的时间和空间差异.展开更多
Manila clam （Ruditapes philippinarum） was monthly sampled from its benthic aquaculture area in Jiaozhou Bay from May 2009 to June 2010.The annual variations of major elemental composition,organic content,fatness and...Manila clam （Ruditapes philippinarum） was monthly sampled from its benthic aquaculture area in Jiaozhou Bay from May 2009 to June 2010.The annual variations of major elemental composition,organic content,fatness and element ratio of Manila clam were examined.The element removal effect of clam farming in Jiaozhou Bay was analyzed based on natural mortality and clam harvest.The results indicated that the variation trend of carbon content in shell （Cshell） was similar to that in clam （Cclam）.Such a variation was higher in summer and autumn than in other seasons,which ranged from 9.10±0.13 to 10.38 ± 0.09 mmol g^-1 and from 11.28 ±0.29 to 12.36±0.06 mmol g 1,respectively.Carbon content of flesh （Cflnesh） showed an opposite variation trend to that of shell in most months,varying from 29.42 ± 0.05 to 33.64 ± 0.62 mmol g^-1.Nitrogen content of shell （Nshell） and flesh （Nflesh） changed seasonally,which was relatively low in spring and summer.Nshell and Nflesh varied from 0.07 ±0.009 to 0.14±0.009 mmol g^-1 and from 5.46 ± 0.12 to 7.39 ± 0.43 mmol g^-1,respectively.Total nitrogen content of clam ranged from 0.50 ± 0.003 to 0.76 ± 0.10 mmol g^-1 with a falling tend except for a high value in March 2010.Phosphorus content of clam （Nclam） fluctuated largely,while phosphorus content of shell （Pshell） was less varied than that of flesh （Pflesh）.Pshell varied from 0.006±0.001 to 0.016±0.001 mmol g^-1; while Pflesh fluctuated between 0.058±0.017 and 0.293±0.029mmolg^-1.Pclam ranged from 0.015±0.002 to 0.041 ±0.006mmolg^-1.Carbon and nitrogen content were slightly affected by shell length,width or height.Elemental contents were closely related to the reproduction cycle.The removal amounts of carbon,nitrogen and phosphorus from clam harvest and natural death in Jiaozhou Bay were 2.92× 10^4t,1420t and 145 t,respectively.The nutrient removal may aid to reduce the concentrations of nitrogen and phosphorus,the main causes of eutrophication,and to maintain the ecosystem health of Jiaozhou Bay.展开更多
文摘地磁暴发生时,电离层会有偏离平均水平的强烈扰动.基于全球电离层TEC及其时间变化率ROTI(Rate of TEC Index)数据,对2014年8月一次中等强度磁暴期间的全球电离层影响进行了分析,探讨了磁暴所引发电离层暴的可能机制.研究发现,本次磁暴伴随有明显的电离层暴效应.磁暴期间:南半球电离层以正相暴为主,北半球电离层暴则整体表现为短暂正相暴后长时间强的负相暴;电离层在北半球的下降比南半球强,并且这种下降持续了约一周时间;低纬区域电离层变化幅度明显小于中纬区域,高纬区域则主要表现为负暴效应;赤道北驼峰出现了明显的南移现象,直至磁赤道两侧双驼峰结构消失.对磁暴期间三个不同扇区的电离层ROTI变化的分析表明:欧洲—非洲扇区磁暴前有电离层闪烁发生,磁暴发生后消失,而东亚—澳大利亚及美洲扇区则无此现象出现.研究结果表明,此次磁暴期间的电离层变化存在明显的时间和空间差异.
基金funded by the Public Science and Technology Research Funds Projects of Ocean (Grant No.200805066)National Natural Science Foundation of China (Grant No.41006083)Shandong Provincial Natural Science Foundation, China (Grant No.ZR2010DQ026)
文摘Manila clam （Ruditapes philippinarum） was monthly sampled from its benthic aquaculture area in Jiaozhou Bay from May 2009 to June 2010.The annual variations of major elemental composition,organic content,fatness and element ratio of Manila clam were examined.The element removal effect of clam farming in Jiaozhou Bay was analyzed based on natural mortality and clam harvest.The results indicated that the variation trend of carbon content in shell （Cshell） was similar to that in clam （Cclam）.Such a variation was higher in summer and autumn than in other seasons,which ranged from 9.10±0.13 to 10.38 ± 0.09 mmol g^-1 and from 11.28 ±0.29 to 12.36±0.06 mmol g 1,respectively.Carbon content of flesh （Cflnesh） showed an opposite variation trend to that of shell in most months,varying from 29.42 ± 0.05 to 33.64 ± 0.62 mmol g^-1.Nitrogen content of shell （Nshell） and flesh （Nflesh） changed seasonally,which was relatively low in spring and summer.Nshell and Nflesh varied from 0.07 ±0.009 to 0.14±0.009 mmol g^-1 and from 5.46 ± 0.12 to 7.39 ± 0.43 mmol g^-1,respectively.Total nitrogen content of clam ranged from 0.50 ± 0.003 to 0.76 ± 0.10 mmol g^-1 with a falling tend except for a high value in March 2010.Phosphorus content of clam （Nclam） fluctuated largely,while phosphorus content of shell （Pshell） was less varied than that of flesh （Pflesh）.Pshell varied from 0.006±0.001 to 0.016±0.001 mmol g^-1; while Pflesh fluctuated between 0.058±0.017 and 0.293±0.029mmolg^-1.Pclam ranged from 0.015±0.002 to 0.041 ±0.006mmolg^-1.Carbon and nitrogen content were slightly affected by shell length,width or height.Elemental contents were closely related to the reproduction cycle.The removal amounts of carbon,nitrogen and phosphorus from clam harvest and natural death in Jiaozhou Bay were 2.92× 10^4t,1420t and 145 t,respectively.The nutrient removal may aid to reduce the concentrations of nitrogen and phosphorus,the main causes of eutrophication,and to maintain the ecosystem health of Jiaozhou Bay.
