Based on the 18-year （1993-2010） National Centers for Environmental Prediction optimum interpolation sea surface temperature （SST） and simple ocean data assimilation datasets, this study investigated the patterns ...Based on the 18-year （1993-2010） National Centers for Environmental Prediction optimum interpolation sea surface temperature （SST） and simple ocean data assimilation datasets, this study investigated the patterns of the SST anomalies （SSTAs） that occurred in the South China Sea （SCS） during the mature phase of the E1 Nifio/Southem Oscillation. The most dominant characteristic was that of the out- of-phase variation between southwestern and northeastern parts of the SCS, which was influenced primarily by the net surface heat flux and by horizontal thermal advection. The negative SSTA in the northeastern SCS was caused mainly by the loss of heat to the atmosphere and because of the cold-water advection from the western Pacific through the Luzon Strait during E1 Nifio episodes. Conversely, it was found that the anomalous large-scale atmospheric circulation and weakened western boundary current during E1 Nifio episodes led to the development of the positive SSTA in the southwestern SCS.展开更多
Of all the methods of studies on bio-estimation of air pollution by lichen flora, the authors cannot justify a choice of one method over another. Consultation of previous work by researchers has allowed us to compare ...Of all the methods of studies on bio-estimation of air pollution by lichen flora, the authors cannot justify a choice of one method over another. Consultation of previous work by researchers has allowed us to compare these methods and to better understand their strengths and limitations. Under the terms of estimating the pollution, these methods are classified into three categories. Some are qualitative, quantitative and others are finally some indirect methods. The methods used to assess the overall air pollution relative value for each station studied. As part of our work, the authors have chosen a quantitative approach based on the combination of two methods. They are based on pollution indices obtained from mathematical formulas based on various parameters related to the lichen flora. They are represented by the I.P. （index poleotolerance） and the I.A.P. （index of atmospheric purity） and these two indices allowed us to map of global air pollution in the city of Skikda and petrochemical industry as well as peri-urban areas （Haddaiek, Hamadi Krouma, Hamrouche Hamoudi, Larbi Ben M＇Hidi）. The authors have identified areas of iso-pollution around different emission centers represented by the largest petrochemical area, traffic and households in urban areas of Skikda, Hamadi Krouma, Hamrouche Hamoudi and Larbi Ben M＇Hidi.展开更多
The ongoing expansion of P. clarkii in the aquatic environments of northern Italy, where it is very common and abundant in most of the streams, lakes and reservoirs, led us to worry about the possibility of invasion i...The ongoing expansion of P. clarkii in the aquatic environments of northern Italy, where it is very common and abundant in most of the streams, lakes and reservoirs, led us to worry about the possibility of invasion into the estuarine and lagoonal brackish environments of the Adriatic coast, which is important not only for their peculiar fauna and flora and high biodiversity, but also for fishing and aquaculture. We carried out laboratory tests to investigate whether this species could live, moult and breed in water with different salinity levels. Several stocks of adult individuals, acclimated before the laboratory experiments, were maintained and monitored daily for a long period （100 days） in glass aquaria with water salinity varying from 5 to 33 ppt. They not only survived during the whole experiment period in levels up to 25 ppt, but also they regularly moulted and mated. These results confirmed that the species could invade the estuarine and brackish environments of the Adriatic coast, with all the implied consequences for the native species of both vertebrates and invertebrates and for human livelihoods.展开更多
The lack of reading habits among Mexican population is an idea based on national and international indicators, which illustrate the danger of this situation; however, these indicators fail to go deeper into the proble...The lack of reading habits among Mexican population is an idea based on national and international indicators, which illustrate the danger of this situation; however, these indicators fail to go deeper into the problem. This project was aimed to obtain more information about the habitus and social representations of college students reading habits, using as theoretical elements the principles developed by Pierre Bourdieu and Serge Moscovici. The project was developed in a public university, located in Mexico＇s northeast region; 19 students were part of the sample group. Two research tools were used to obtain data： survey and focus group. The project analyzed academic and environmental aspects, beyond the ＂ought to be＂, that affected the development and provided characteristics on the daily sociocultural reality of the students, with a view of the real environment of the students without ＂make-up＂. The project deepened into the analysis of the reading practices and not only the usual numeric indicators, which traditionally condemn the reading practices in Mexico. The results of this study showed that students read a lot more than what they and their teachers think they do, this taking into consideration electronic documents, general interest publications, and commercial magazines, among others. The point of view of some teachers and researchers, when it comes to reading habits recognize non-academic, simple and interesting reading more important impact on their reading habits shows a tendency to be pedantic and canonic; it does not for young people, which in the long term, could have a展开更多
The aim of this work is the assessment of the behavior of the radiation over studied area at the different seasons of the year using mathematical model. To achieve this purpose, the dispersion factor has been calculat...The aim of this work is the assessment of the behavior of the radiation over studied area at the different seasons of the year using mathematical model. To achieve this purpose, the dispersion factor has been calculated. The calculated dispersion factor gives an indication about the behavior and the distribution of pollutants in the atmosphere. Since the used model requires specific measuring hourly metrological data over long periods of time at least one year such as wind speed, incoming solar, radiation and wind direction for studied area. Also terrain information and population distribution should be taken into consideration. The atmospheric parameters such as monthly wind rose, hourly stability classes and joint frequency have been determined using developed computer programs. The results of wind rose shown that the prevailing wind direction for studied area is northeast direction in winter. This situation give us a primary knowledge about months （months of winter） at which the studied area may be affected by the air coming from the east borders. The results of dispersion factor indicate that the sectors S, SSE and SE for the studying area are greatly exposed to air which may be polluted.展开更多
In 2013, the China Geological Survey and Guangzhou Marine Geological Survey conducted the second Chinese gas hydrate expedition in the northern South China Sea （SCS） and successfully obtained visible gas hydrate sam...In 2013, the China Geological Survey and Guangzhou Marine Geological Survey conducted the second Chinese gas hydrate expedition in the northern South China Sea （SCS） and successfully obtained visible gas hydrate samples. Five of the thirteen drilling sites were cored for further research. In this work, Site GMGS2-08 is selected for the stable isotopic analy- sis of foraminifera present in the boreholes in order to reveal the carbon isotopic characteristics of the foraminifera and their response to methane release in the gas hydrate geological system. Our results show that the methane content at Site GMGS2-08 is extremely high, with headspace methane concentrations up to 39300 μmol L^-1. The hydrocarbon δ^13C values, ranging from -69.4%o to -72.3‰ PDB, distinctly indicate biogenic generation. Based on the δD analytical results （-183‰ to -185‰ SMOW）, headspace methane is further discriminated to be microbial gas, derived from CO2 reduction. By isotopic measurement, five light δ^13C events are found in the boreholes from Site GMGS2-08, with foraminiferal δ^13C values being ap- parently lower than the normal variation range found in the glacial-interglacial cycles of the SCS. The δ^13C values of benthic Uvigerina peregrina are extremely depleted （as low as -15.85‰ PDB）, while those of planktonic Globigerinoides ruber reach -5.68‰ PDB. Scanning electron micrograph （SEM） studies show that foraminiferal tests have experienced post-depositional alteration, infilled with authigenic carbonate, and the diagenetic mineralization is unlikely to be related to the burial depths. The correlation calculation suggests that the anaerobic oxidation of organic matter has only weak influences on the δ^13C com- position of benthic foraminifera. This means that the anomalous δ^13C depletions are predominantly attributed to the overprint- ing of secondary carbonates derived from the anaerobic oxidation of methane （AOM）. Furthermore, the negative δ^13C anoma- lies, coupled with the positive δ^18O anomalies observed at Site GMGS2-08, are most likely the critical pieces of evidence for gas hydrate dissociation in the geological history of the study area.展开更多
基金Supported by the National Natural Science Foundation of China(No.41306026)the Scientific Research Foundation of the Third Institute of Oceanography,SOA(No.2013009)+1 种基金the National Basic Research Program of China(973 Program)(No.2011CB403504)the National Special Research Fund for Non-Profit Marine Sector(No.201005005-2)
文摘Based on the 18-year （1993-2010） National Centers for Environmental Prediction optimum interpolation sea surface temperature （SST） and simple ocean data assimilation datasets, this study investigated the patterns of the SST anomalies （SSTAs） that occurred in the South China Sea （SCS） during the mature phase of the E1 Nifio/Southem Oscillation. The most dominant characteristic was that of the out- of-phase variation between southwestern and northeastern parts of the SCS, which was influenced primarily by the net surface heat flux and by horizontal thermal advection. The negative SSTA in the northeastern SCS was caused mainly by the loss of heat to the atmosphere and because of the cold-water advection from the western Pacific through the Luzon Strait during E1 Nifio episodes. Conversely, it was found that the anomalous large-scale atmospheric circulation and weakened western boundary current during E1 Nifio episodes led to the development of the positive SSTA in the southwestern SCS.
文摘Of all the methods of studies on bio-estimation of air pollution by lichen flora, the authors cannot justify a choice of one method over another. Consultation of previous work by researchers has allowed us to compare these methods and to better understand their strengths and limitations. Under the terms of estimating the pollution, these methods are classified into three categories. Some are qualitative, quantitative and others are finally some indirect methods. The methods used to assess the overall air pollution relative value for each station studied. As part of our work, the authors have chosen a quantitative approach based on the combination of two methods. They are based on pollution indices obtained from mathematical formulas based on various parameters related to the lichen flora. They are represented by the I.P. （index poleotolerance） and the I.A.P. （index of atmospheric purity） and these two indices allowed us to map of global air pollution in the city of Skikda and petrochemical industry as well as peri-urban areas （Haddaiek, Hamadi Krouma, Hamrouche Hamoudi, Larbi Ben M＇Hidi）. The authors have identified areas of iso-pollution around different emission centers represented by the largest petrochemical area, traffic and households in urban areas of Skikda, Hamadi Krouma, Hamrouche Hamoudi and Larbi Ben M＇Hidi.
文摘The ongoing expansion of P. clarkii in the aquatic environments of northern Italy, where it is very common and abundant in most of the streams, lakes and reservoirs, led us to worry about the possibility of invasion into the estuarine and lagoonal brackish environments of the Adriatic coast, which is important not only for their peculiar fauna and flora and high biodiversity, but also for fishing and aquaculture. We carried out laboratory tests to investigate whether this species could live, moult and breed in water with different salinity levels. Several stocks of adult individuals, acclimated before the laboratory experiments, were maintained and monitored daily for a long period （100 days） in glass aquaria with water salinity varying from 5 to 33 ppt. They not only survived during the whole experiment period in levels up to 25 ppt, but also they regularly moulted and mated. These results confirmed that the species could invade the estuarine and brackish environments of the Adriatic coast, with all the implied consequences for the native species of both vertebrates and invertebrates and for human livelihoods.
文摘The lack of reading habits among Mexican population is an idea based on national and international indicators, which illustrate the danger of this situation; however, these indicators fail to go deeper into the problem. This project was aimed to obtain more information about the habitus and social representations of college students reading habits, using as theoretical elements the principles developed by Pierre Bourdieu and Serge Moscovici. The project was developed in a public university, located in Mexico＇s northeast region; 19 students were part of the sample group. Two research tools were used to obtain data： survey and focus group. The project analyzed academic and environmental aspects, beyond the ＂ought to be＂, that affected the development and provided characteristics on the daily sociocultural reality of the students, with a view of the real environment of the students without ＂make-up＂. The project deepened into the analysis of the reading practices and not only the usual numeric indicators, which traditionally condemn the reading practices in Mexico. The results of this study showed that students read a lot more than what they and their teachers think they do, this taking into consideration electronic documents, general interest publications, and commercial magazines, among others. The point of view of some teachers and researchers, when it comes to reading habits recognize non-academic, simple and interesting reading more important impact on their reading habits shows a tendency to be pedantic and canonic; it does not for young people, which in the long term, could have a
文摘The aim of this work is the assessment of the behavior of the radiation over studied area at the different seasons of the year using mathematical model. To achieve this purpose, the dispersion factor has been calculated. The calculated dispersion factor gives an indication about the behavior and the distribution of pollutants in the atmosphere. Since the used model requires specific measuring hourly metrological data over long periods of time at least one year such as wind speed, incoming solar, radiation and wind direction for studied area. Also terrain information and population distribution should be taken into consideration. The atmospheric parameters such as monthly wind rose, hourly stability classes and joint frequency have been determined using developed computer programs. The results of wind rose shown that the prevailing wind direction for studied area is northeast direction in winter. This situation give us a primary knowledge about months （months of winter） at which the studied area may be affected by the air coming from the east borders. The results of dispersion factor indicate that the sectors S, SSE and SE for the studying area are greatly exposed to air which may be polluted.
基金supported by the National Natural Science Foundation of China (Grant No. 41372012)the Key Scientific Project from China Geological Survey (Grant No. GZH201100305-06-02)the Key Laboratory of Marine Mineral Resources (Grant No. KLMMR-2013-A-32)
文摘In 2013, the China Geological Survey and Guangzhou Marine Geological Survey conducted the second Chinese gas hydrate expedition in the northern South China Sea （SCS） and successfully obtained visible gas hydrate samples. Five of the thirteen drilling sites were cored for further research. In this work, Site GMGS2-08 is selected for the stable isotopic analy- sis of foraminifera present in the boreholes in order to reveal the carbon isotopic characteristics of the foraminifera and their response to methane release in the gas hydrate geological system. Our results show that the methane content at Site GMGS2-08 is extremely high, with headspace methane concentrations up to 39300 μmol L^-1. The hydrocarbon δ^13C values, ranging from -69.4%o to -72.3‰ PDB, distinctly indicate biogenic generation. Based on the δD analytical results （-183‰ to -185‰ SMOW）, headspace methane is further discriminated to be microbial gas, derived from CO2 reduction. By isotopic measurement, five light δ^13C events are found in the boreholes from Site GMGS2-08, with foraminiferal δ^13C values being ap- parently lower than the normal variation range found in the glacial-interglacial cycles of the SCS. The δ^13C values of benthic Uvigerina peregrina are extremely depleted （as low as -15.85‰ PDB）, while those of planktonic Globigerinoides ruber reach -5.68‰ PDB. Scanning electron micrograph （SEM） studies show that foraminiferal tests have experienced post-depositional alteration, infilled with authigenic carbonate, and the diagenetic mineralization is unlikely to be related to the burial depths. The correlation calculation suggests that the anaerobic oxidation of organic matter has only weak influences on the δ^13C com- position of benthic foraminifera. This means that the anomalous δ^13C depletions are predominantly attributed to the overprint- ing of secondary carbonates derived from the anaerobic oxidation of methane （AOM）. Furthermore, the negative δ^13C anoma- lies, coupled with the positive δ^18O anomalies observed at Site GMGS2-08, are most likely the critical pieces of evidence for gas hydrate dissociation in the geological history of the study area.
