The trophic states of 35 reservoirs were investigated in the region of Chongqing,Southwest China.The results showed that the concentrations of nutrients and chlorophyll a were high and organic pollution and transparen...The trophic states of 35 reservoirs were investigated in the region of Chongqing,Southwest China.The results showed that the concentrations of nutrients and chlorophyll a were high and organic pollution and transparence(SD) were low in the water body.The concentrations of total nitrogen(TN) range from 0.52 mg/L to 5.94 mg/L and those of total phosphorus(TP) range from 0.002 mg/L to 0.598 mg/L.Chemical oxygen demand(COD) ranges from 0.75 mg/L to 9.3 mg/L and SD ranges from 0.48 m to 3.2 m.There was a significant positive correlation between COD and chlorophyll a,but a significant negative correlation between SD and chlorophyll a.In terms of the integrated nutrition state index,the eutrophication states of the reservoirs were assessed.Of the investigated reservoirs,about 22 reached the grade of eutrophication.Only one reservoir was in the state of oligotropher,the rest were in the state of mestropher.Integrated nutrition state indices range from 25.4 to 74.5.The storage capacity of nutrients in the reservoirs was calculated.The stored TN,TP and COD were about 4731,206 and 10259 t,respectively.The main pollution sources are industrial and domestic wastes.With the development of aquaculture,the contamination level increases gradually.展开更多
Mercury pollution in the Three Gorges Reservoir area of P.R.China merits special attention.We investigated into the current situation in the Chongqing part of the Reservoir area,identified the pollution sources and pr...Mercury pollution in the Three Gorges Reservoir area of P.R.China merits special attention.We investigated into the current situation in the Chongqing part of the Reservoir area,identified the pollution sources and proposed some suggestions for the remediation and prevention of mercury pollution in this area.Atmospheric mercury in Chongqing was mainly from coal burning and releases of mercury-containing products such as various types of lights and fever thermometers.Urban drainage in Chongqing and Changshou,and runoffs from the high mercury background area in the lower reaches of the Wujiang River contributed most of the mercury in the water of the Yangtze River.A majority of the blame should be laid on mercury and gold mining in the Wujiang valley.We suggested foresting sloping lands to relieve soil erosion and prevent mercury-bearing soil from running into rivers,educational activities to discourage use of mercury-containing products and improved infrastructure to collect mercury-containing wastes for reducing mercury releases,more facilities for treating wastewater and solid waste to accommodate increased requirements of discharge,and growing selected perennial plants in mercury-contaminated land to absorb the mercury in soil.We also suggested concerted operation of a dedicated water-quality monitoring system,reinforced legislation and an effective administrative mechanism to ensure lasting efforts are invested in curbing mercury releases and restoring mercury contaminated land and water in the Reservoir area.展开更多
Purpose: So far, there have been few studies that discussed children's reading environment in China's poverty-stricken areas, this study aims to explore differences existed in extracurricular reading environme...Purpose: So far, there have been few studies that discussed children's reading environment in China's poverty-stricken areas, this study aims to explore differences existed in extracurricular reading environment between urban and rural children in Chongqing Reservoir Area with empirical evidence.Design/methodology/approach: Using a questionnaire survey, empirical data was collected from 105 participants. Then proposed hypotheses and the reliability of the observation variables were respectively examined with ANOVA and factor analysis. The statistical analysis software SPSS19.0 was used to analyze the data.Findings: Our results showed that 1) differences did exist in school and social reading environment between urban and rural children in Chongqing Reservoir Area; 2) differences in family reading environment between urban and rural children in Chongqing Reservoir Area were not obviously observed.Research limitations: The empirical data were collected from only one county of Chongqing Reservoir Area, which may have partially affected the generalization of our conclusions. In addition, the response rate of questionnaires was comparatively low due to a relatively limited research period. Practical implications: This study would provide some reference for governments, libraries, schools and families to consider how to jointly narrow the gap in the extracurricular reading circumstance between urban and rural children in Chongqing Reservoir Area.Originality value: This is one of the first studies to explore similarities and differences in extracurricular reading environment between urban and rural children in Chinese povertystricken areas, which will help research communities to gain a deeper understanding of children's reading environment in Chinese Reservoir Area.展开更多
Many karst geodes have been found in the pure Iimestone on the top Maokou formation (Permian) in the axial part of anticlines and lower part hydrological networks in Chongqing region. It is sometimes a reservoir natur...Many karst geodes have been found in the pure Iimestone on the top Maokou formation (Permian) in the axial part of anticlines and lower part hydrological networks in Chongqing region. It is sometimes a reservoir natural gas. Calcite megacryst decorates the wall of the geodes which believed to he formed in Tertiary.展开更多
The temporal-spatial distribution features including time distribution,horizontal and vertical spatial distribution of archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges R...The temporal-spatial distribution features including time distribution,horizontal and vertical spatial distribution of archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area are analyzed based on GIS spatial analysis.The successive pollen record of deposited peat stratum since the Paleolithic Age in the Dajiuhu Basin of Shennongjia is used in combination with the research of the historical environmental evolution to reconstruct the Paleoenvironment in the Three Gorges Reservoir of Chongqing area.Through the comparison of the temporal-spatial distribution of the archaeological sites and the natural environment,the relation between the distribution of the archaeological sites and the natural environment evolution and disaster changes from the Neolithic Age to the Tang and Song Dynasties has been discussed.Study shows that 677 archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area increase gradually from west to east and from high land to low land.Most of the sites are distributed along the river and aggregated at the confluence.Obviously,the altitudes of archaeological sites in the Paleolithic Age and the Neolithic Age are much higher than those of historical sites.The analysis suggests:(1)the human beings of every times would like to choose the first or the second river terrace as living sites which are nearer to the water source and are easier to with- stand flood.The pre-historical sites of earlier ages are often located at the higher altitude place because of the tectonic uplift and downcutting of rivers since Holocene.(2)Due to the rugged terrain in Chongqing area,most of the sites are located along the river sides,for example,the wide river valley and terrace,which could provide wider living space caused by the lateral erosion and deposition of the river course.(3)The early residents mainly relied on fishing,hunting and agriculture,and the rugged terrain of the mountainous area restricted the development of farming.However,in the confluence region,the fertilized plain provided an ideal location for farming and fishing.(4)The temporal-spatial distribution of archeological sites in this area is significantly affected by the climate condition.展开更多
To further understand shale reservoir characteristics of Wufeng Formation and Longmaxi Formation in the Wuxi area,northeast Chongqing,based on drilling data of Well WX2,and taking the graptolite biostratigraphy as the...To further understand shale reservoir characteristics of Wufeng Formation and Longmaxi Formation in the Wuxi area,northeast Chongqing,based on drilling data of Well WX2,and taking the graptolite biostratigraphy as the standard marker of stratigraphic division and comparison,the geochemistry,petrology,reservoir space and properties of organic-rich black shale were well investigated,and its gasbearing capacity and controlling factors were also analyzed.The result shows that in the Wufeng Formation and Longmaxi Formation of Well WX2,the organic-rich shale is 89.8 m thick and is characterized by good kerogen type,high organic abundance,moderate maturity and favorable hydrocarbongeneration condition,and the graptolite sequence is developed completely and continuously;the organic abundance is influenced by depositional rate,and the slow depositional rate is favorable for accumulation of organic matter in the black graptolite shale;from top to bottom,content of siliceous minerals increases and content of clay minerals decrease,therefore the brittleness increases;the organicrich siliceous shale and clay siliceous shale are favorable lithofacies for development of shale reservoirs;the nanopore is dominated by the parallel-plate pore with four open sides and has good connectivity;the pore size distribution curve has the multimodal characteristic,and the pore diameter mainly is in the range of 0.42e0.62 nm and the range of 3e5 nm;organic pores and interlayer pores of clay minerals make the greatest contribution to the total pore volume,while pores of brittle minerals have the least contribution;from top to bottom,organic pores gradually increase while interlayer pores of clay minerals gradually decrease;the on-site core gas content exceeds 8 m3/t,and the gas-bearing capacity is jointly controlled by hydrocarbon generation,reservoir and preservation conditions;and the WF2-LM6 biozone of the Katian to the early Aeronian is the high-quality shale reservoir,where the LM1 biozone of the Hirnantian was the best“sweet spot”which is the target of horizontal well drilling.展开更多
文摘The trophic states of 35 reservoirs were investigated in the region of Chongqing,Southwest China.The results showed that the concentrations of nutrients and chlorophyll a were high and organic pollution and transparence(SD) were low in the water body.The concentrations of total nitrogen(TN) range from 0.52 mg/L to 5.94 mg/L and those of total phosphorus(TP) range from 0.002 mg/L to 0.598 mg/L.Chemical oxygen demand(COD) ranges from 0.75 mg/L to 9.3 mg/L and SD ranges from 0.48 m to 3.2 m.There was a significant positive correlation between COD and chlorophyll a,but a significant negative correlation between SD and chlorophyll a.In terms of the integrated nutrition state index,the eutrophication states of the reservoirs were assessed.Of the investigated reservoirs,about 22 reached the grade of eutrophication.Only one reservoir was in the state of oligotropher,the rest were in the state of mestropher.Integrated nutrition state indices range from 25.4 to 74.5.The storage capacity of nutrients in the reservoirs was calculated.The stored TN,TP and COD were about 4731,206 and 10259 t,respectively.The main pollution sources are industrial and domestic wastes.With the development of aquaculture,the contamination level increases gradually.
基金the Natural Science Foundation of China under the Grant No.20377054
文摘Mercury pollution in the Three Gorges Reservoir area of P.R.China merits special attention.We investigated into the current situation in the Chongqing part of the Reservoir area,identified the pollution sources and proposed some suggestions for the remediation and prevention of mercury pollution in this area.Atmospheric mercury in Chongqing was mainly from coal burning and releases of mercury-containing products such as various types of lights and fever thermometers.Urban drainage in Chongqing and Changshou,and runoffs from the high mercury background area in the lower reaches of the Wujiang River contributed most of the mercury in the water of the Yangtze River.A majority of the blame should be laid on mercury and gold mining in the Wujiang valley.We suggested foresting sloping lands to relieve soil erosion and prevent mercury-bearing soil from running into rivers,educational activities to discourage use of mercury-containing products and improved infrastructure to collect mercury-containing wastes for reducing mercury releases,more facilities for treating wastewater and solid waste to accommodate increased requirements of discharge,and growing selected perennial plants in mercury-contaminated land to absorb the mercury in soil.We also suggested concerted operation of a dedicated water-quality monitoring system,reinforced legislation and an effective administrative mechanism to ensure lasting efforts are invested in curbing mercury releases and restoring mercury contaminated land and water in the Reservoir area.
基金jointly supported by the Ministry of Education of China for the Returned Overseas Chinese Scholars(granted in 2012)the Educational Science Programmed Research Project of Chongqing(Grant No.:10-GJ-0234)
文摘Purpose: So far, there have been few studies that discussed children's reading environment in China's poverty-stricken areas, this study aims to explore differences existed in extracurricular reading environment between urban and rural children in Chongqing Reservoir Area with empirical evidence.Design/methodology/approach: Using a questionnaire survey, empirical data was collected from 105 participants. Then proposed hypotheses and the reliability of the observation variables were respectively examined with ANOVA and factor analysis. The statistical analysis software SPSS19.0 was used to analyze the data.Findings: Our results showed that 1) differences did exist in school and social reading environment between urban and rural children in Chongqing Reservoir Area; 2) differences in family reading environment between urban and rural children in Chongqing Reservoir Area were not obviously observed.Research limitations: The empirical data were collected from only one county of Chongqing Reservoir Area, which may have partially affected the generalization of our conclusions. In addition, the response rate of questionnaires was comparatively low due to a relatively limited research period. Practical implications: This study would provide some reference for governments, libraries, schools and families to consider how to jointly narrow the gap in the extracurricular reading circumstance between urban and rural children in Chongqing Reservoir Area.Originality value: This is one of the first studies to explore similarities and differences in extracurricular reading environment between urban and rural children in Chinese povertystricken areas, which will help research communities to gain a deeper understanding of children's reading environment in Chinese Reservoir Area.
文摘Many karst geodes have been found in the pure Iimestone on the top Maokou formation (Permian) in the axial part of anticlines and lower part hydrological networks in Chongqing region. It is sometimes a reservoir natural gas. Calcite megacryst decorates the wall of the geodes which believed to he formed in Tertiary.
基金Supported by the Key Project of the National Natural Science Foundation of China(Grant No.90411015)the University Doctoral Foundation(Grant No.20050284011)+2 种基金Foundation of Important Basic Research at Nanjing University(Grant No.0209005206)Open Foundation of the State Key Laboratory of Loess and Quaternary Geology from the Institute of Earth Environment,CAS(Grant No.SKLLQG0503)the Physical Geography of"985"Items and the Test Foundation of Modern Analyses Center of Nanjing University(Grant No.0209001309)
文摘The temporal-spatial distribution features including time distribution,horizontal and vertical spatial distribution of archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area are analyzed based on GIS spatial analysis.The successive pollen record of deposited peat stratum since the Paleolithic Age in the Dajiuhu Basin of Shennongjia is used in combination with the research of the historical environmental evolution to reconstruct the Paleoenvironment in the Three Gorges Reservoir of Chongqing area.Through the comparison of the temporal-spatial distribution of the archaeological sites and the natural environment,the relation between the distribution of the archaeological sites and the natural environment evolution and disaster changes from the Neolithic Age to the Tang and Song Dynasties has been discussed.Study shows that 677 archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area increase gradually from west to east and from high land to low land.Most of the sites are distributed along the river and aggregated at the confluence.Obviously,the altitudes of archaeological sites in the Paleolithic Age and the Neolithic Age are much higher than those of historical sites.The analysis suggests:(1)the human beings of every times would like to choose the first or the second river terrace as living sites which are nearer to the water source and are easier to with- stand flood.The pre-historical sites of earlier ages are often located at the higher altitude place because of the tectonic uplift and downcutting of rivers since Holocene.(2)Due to the rugged terrain in Chongqing area,most of the sites are located along the river sides,for example,the wide river valley and terrace,which could provide wider living space caused by the lateral erosion and deposition of the river course.(3)The early residents mainly relied on fishing,hunting and agriculture,and the rugged terrain of the mountainous area restricted the development of farming.However,in the confluence region,the fertilized plain provided an ideal location for farming and fishing.(4)The temporal-spatial distribution of archeological sites in this area is significantly affected by the climate condition.
基金National Natural Science Foundation of China, No.40801077 Key Scientific Research Projects of the Ministry of Education, No.209100+1 种基金 Natural Science Foundation of Chongqing, No.CSTC, 2008BB7367 Science ＆ Technology Research Project Supported by Chongqing Municipal Education Commission, No.K J070811
基金supported by the National Science and Technology Major Project of China(No.2017ZX05035)the National Basic Research Program of China(973 Program)(No.2013CB228000).
文摘To further understand shale reservoir characteristics of Wufeng Formation and Longmaxi Formation in the Wuxi area,northeast Chongqing,based on drilling data of Well WX2,and taking the graptolite biostratigraphy as the standard marker of stratigraphic division and comparison,the geochemistry,petrology,reservoir space and properties of organic-rich black shale were well investigated,and its gasbearing capacity and controlling factors were also analyzed.The result shows that in the Wufeng Formation and Longmaxi Formation of Well WX2,the organic-rich shale is 89.8 m thick and is characterized by good kerogen type,high organic abundance,moderate maturity and favorable hydrocarbongeneration condition,and the graptolite sequence is developed completely and continuously;the organic abundance is influenced by depositional rate,and the slow depositional rate is favorable for accumulation of organic matter in the black graptolite shale;from top to bottom,content of siliceous minerals increases and content of clay minerals decrease,therefore the brittleness increases;the organicrich siliceous shale and clay siliceous shale are favorable lithofacies for development of shale reservoirs;the nanopore is dominated by the parallel-plate pore with four open sides and has good connectivity;the pore size distribution curve has the multimodal characteristic,and the pore diameter mainly is in the range of 0.42e0.62 nm and the range of 3e5 nm;organic pores and interlayer pores of clay minerals make the greatest contribution to the total pore volume,while pores of brittle minerals have the least contribution;from top to bottom,organic pores gradually increase while interlayer pores of clay minerals gradually decrease;the on-site core gas content exceeds 8 m3/t,and the gas-bearing capacity is jointly controlled by hydrocarbon generation,reservoir and preservation conditions;and the WF2-LM6 biozone of the Katian to the early Aeronian is the high-quality shale reservoir,where the LM1 biozone of the Hirnantian was the best“sweet spot”which is the target of horizontal well drilling.
