《中国扬子区兰多维列统特列奇阶及其与英国的对比》一书(陈旭和戎嘉余,1996)有以下结论:①将回星哨组、茅山组、西坑组等的层位归属于特列奇阶上部;②将回星哨组、茅山组及其相当地层与英国特列奇阶对比;③将扬子区特列奇阶的顶界置于...《中国扬子区兰多维列统特列奇阶及其与英国的对比》一书(陈旭和戎嘉余,1996)有以下结论:①将回星哨组、茅山组、西坑组等的层位归属于特列奇阶上部;②将回星哨组、茅山组及其相当地层与英国特列奇阶对比;③将扬子区特列奇阶的顶界置于回星哨组、茅山组及其相当地层之顶;④将回星哨组、茅山组、西坑组等地层资料编制的古地理图称为特列奇期晚期古地理图;⑤将回星哨组、茅山组、西坑组等地层与上覆中泥盆统—中二叠统之间的不整合面代表的上升运动,称为“特列奇期的扬子上升”。笔者等依据多年对扬子地台志留纪地层剖面的实地考察和近数十年来扬子区坟头组中—上部、茅山组、回星哨组、小溪峪组、西坑组等地层中文洛克世、拉德洛世、普里多利世早期古生物化石的发现,认为:①回星哨组、小溪峪组、茅山组、西坑组等的层位是文洛克统—普里多利统;②回星哨组、小溪峪组等大致与英国的文洛克统—普里多利统对比;③回星哨组、小溪峪组、茅山组的顶界是文洛克统—普里多利统剥蚀后残留的层位随地而异的顶界;④根据回星哨组、西坑组、茅山组等地层资料编制的古地理图应是文洛克世—普里多利世古地理图;⑤“扬子地台整个上升”(Huang T K,1945)的时代是志留纪末期,没有“特列奇期的扬子上升”。特提出商榷。上述这些地层时代的解决,对扬子区志留系4统层序的建立具有重要意义,而且也为中国扬子区与英国命名剖面志留系的对比以及中国南方早古生代加里东运动最后一幕时代的再次确定提供了地层学和古生物方面的依据。展开更多
Aim To investigate the chemical composition of Ranunculus sieboldii Miq..Methods Repeated column chromatography over silica gel, polyamide and RP-18 followed by gelfiltration on sephadex LH-20 were used to isolate che...Aim To investigate the chemical composition of Ranunculus sieboldii Miq..Methods Repeated column chromatography over silica gel, polyamide and RP-18 followed by gelfiltration on sephadex LH-20 were used to isolate chemical constituents, and their structures wereelucidated by extensive spectroscopic methods (UV, IR, MS, ~1H NMR, ^(13)C NMR) including 2D NMR(COSY, HMQC, HMBC, NOESY) techniques and by direct comparing spectral data with those reported inliterature. Results Five flavonoid glycosides named apigenin-4'-O-α-L-rhamnopyranoside (1),apigenin-7-O-β-D-glucopyranosyl-4'-O-α-L-rhamnopyranoside (2), apigenin-8-C-α-L-arabinopyranoside(3), apigenin-8-C-β-D-ga-lactopyranoside (4) , tricin-7-O-β-D-glucopyranoside (5), together withtricin (6), luteolin (7), scopoletin (8), esculetin (9), scoparone (10), ferulic acid (11),protocatechuic acid (12) , and tematolide (13) were isolated from the 95% etha-nolic extract of itswhole plant, and their cytotoxic activities were preliminarily tested. Conclusion Compounds 1-12were obtained from this genus and compound 13 from this species for the first time. Furthermore,compound 1 was for the first time isolated from nature while the ^(13)C NMR data of compounds 2 and3 are reported for the first time. The bioassay revealed that compound 1 was active against BEL-7407and A549 cell lines (IC_(45) 43, 77 μg·mL^(-1)), 8 and 10 showed inhibitory activities on KB celllines (IC_(50) 78, 44 μg·mL^(-1)) and HL-60 cell lines (Ic_(50) 85, 85 μg·mL^(-1)), while 7exerted moderate cytotoxic activities on KB, BFL-7407, A549 and HL-60 cell lines with their IC_(50)being 51, 55, 44 and 10 μg·mL^(-1) , respectively.展开更多
The polymorphism of MHC class II B gene in 14 Chinese alligators was analyzed, which came from three different areas: a wild population from Xuancheng, Anhui, a captive population from Changxing, Zhejiang, and a capt...The polymorphism of MHC class II B gene in 14 Chinese alligators was analyzed, which came from three different areas: a wild population from Xuancheng, Anhui, a captive population from Changxing, Zhejiang, and a captive population from Anhui Research Center for Reproduction of Chinese Alligators. The gene fragment was amplified using a pair of specific primers designed from the MHC gene sequence of the spectacled caiman. A total of 34 sequence haplotypes of exon 3 were detected in the sampled Chinese alligators. The numbers of haplotypes of the 3 Chinese alligator populations were 15, 10, and 9, respectively. The overall estimation of the MHC polymorphism in the Chinese alligator population was higher than those in mammals and in cypdnid fish, The rates of nonsynonymous substitutions (dN) occurred at a significantly lower frequency than that of synonymous substitutions (ds), which were not consistent with the common rule. This result might suggest that the polymorphism of exon 3 seemed not to be maintained by the balancing selection. The neutrality test of Tajima excluded the null hypothesis that the polymorphism of exon 3 was generated by a random drift, and the fact that D = -0.401 indicated an excess of rare mutations in the Chinese alligator. The nucleotide diversity of the sequences and the phylogenetic relations were also analyzed, and the results suggested that there was no significant difference in genetic diversity among the 3 populations of Chinese alligator.展开更多
The Chinese alligator (Alligator sinensis) is a critically endangered species in China. Wild populations of Chinese alligator are on the edge of extinction. Through a release program, some captive-bred alligators wi...The Chinese alligator (Alligator sinensis) is a critically endangered species in China. Wild populations of Chinese alligator are on the edge of extinction. Through a release program, some captive-bred alligators will be selected and released into the wild to supplement and renew natural populations. The purpose of this study was to provide data to select healthy individuals for release. Through bacteriological and molecular identification, six different genera, eight species and an unclassified bacterium were identified in 13 bacterial strains, which were isolated from the cloaca of 25 Chinese alligators. One genus and four species were identified in eight bacterial strains, which were isolated from the water where the alligators live. According to the analysis, except for the unclassified bacterium, the other bacteria from the cloaca were not pathogenic and were different from the bacteria isolated from the water. Thus, it was concluded that the 24 Chinese alligators were healthy, and could be selected to be released into the wild. As subject AS 12 was identified carrying an unclassified bacteria, of which the characteristics were unknown, it was suggested that the AS 12 individual not be released.展开更多
The reasons for the Yangtze River flood calamity in 1998 are briefly introduced. The authors believe that using a 'soil reservoir' concept is an important means to help control flooding of the Yangtze River.A ...The reasons for the Yangtze River flood calamity in 1998 are briefly introduced. The authors believe that using a 'soil reservoir' concept is an important means to help control flooding of the Yangtze River.A 'soil reservoir' has a large potential storage capacity and its water can be rapidly 'discharged' into the underground water in a timely fashion. The eroded, infertile soils of the Yangtze River Watershed are currently an obstacle to efficient operation of the 'soil reservoir'. The storage capacity of this 'soil reservoir'has been severely hampered due to intensive soil erosion and the formation of soil crusts. Therefore, possible measures to control floods in the Yangtze River Watershed include: rehabilitating the vegetation to preserve soil and water on the eroded infertile soils, enhancing infiltration of the different soil types, and utilizing the large 'soil reservoir' of the upper reaches of the Yangtze River.展开更多
Land use/land cover change (LUCC) is a focus of the research of global environmental changes. The middle and upper reaches of the Yangtze River, which are the most ecologically fragile mountainous area in China as wel...Land use/land cover change (LUCC) is a focus of the research of global environmental changes. The middle and upper reaches of the Yangtze River, which are the most ecologically fragile mountainous area in China as well as one of the areas in China with most notable LUCC, have been on the Chinese Government's list of priority areas for ecological restoration. This paper is to reveal the trend of LUCC and the ecological degradation arising from it, and to provide a basis for the future sustainable use of land resources in the region based on a detailed analysis of Yiliang County. Based on the county's land use/cover maps in 1960, 1980 and 2000 drawn with the aid of aerial photograph interpretation, field investigation and GIS based spatial-temporal data analysis, LUCC during 1960~2000 period and the ecological degradation arising from it were analyzed. Using the Markv model, the paper brings out a forecast of what the county's LUCC would be like if the county's current land use continues, as well as the reasons and countermeasures for restoring degraded ecosystems.展开更多
To assess the effects of hypoxia, macrobenthic communities along an estuarine gradient of the Changjiang estuary and adjacent continental shelf were analyzed. This revealed spatial variations in the communities and re...To assess the effects of hypoxia, macrobenthic communities along an estuarine gradient of the Changjiang estuary and adjacent continental shelf were analyzed. This revealed spatial variations in the communities and relationships with environmental variables during periods of reduced dissolved oxygen (DO) concentration in summer. Statistical analyses revealed significant differences in macrobenthic community composition among the three zones: estuarine zone (EZ), mildly hypoxic zone (MHZ) in the continental shelf, and norrnoxic zone (NZ) in the continental shelf(Global R=0.206, P=0.002). Pairwise tests showed that the macrobenthic community composition of the EZ was significantly different from the MHZ (pairwise test R=0.305, P=0.001) and the NZ (pairwise test R=0.259, P=-0.001). There was no significant difference in macrobenthic communities between the MHZ and the NZ (pairwise test R=0.062, P=-0.114). The taxa included small and typically opportunistic polychaetes, which made the greatest contribution to the dissimilarity between the zones. The effects of mild hypoxia on the macrobenthic communities are a result not only of reduced DO concentration but also of differences in environmental variables such as temperature, salinity, and nutrient concentrations caused by stratification.展开更多
PCBs pollutants are measured on tidal-flat sediments of Yangtze estuary by a high resolution capillary column gas chromatography ( HP6890 ) equipped with an 63Ni electron capture detector ( ECD ). The concentration te...PCBs pollutants are measured on tidal-flat sediments of Yangtze estuary by a high resolution capillary column gas chromatography ( HP6890 ) equipped with an 63Ni electron capture detector ( ECD ). The concentration tendency of PCBs is Phragmites zone > Scirpus zone > bare mudflats. There are linear relations between PCBs and TOC and > 63μm grain size percentage ( in volume ). The low chlorinated congeners may be more important than the high chlorinated congeners in this area. PCBs prefer to accumulate in the sediments near sewage outlets and Phragmites zone. The sediments’ PCBs pollution ( 10.7 ~ 28.6 ng/g, dry weight ) in the Yangtze estuary tidal-flat is less serious than that of the most of other areas in the world .But the detected ratio is 100%, even the Jiuduansha shoal has detected PCBs, so much attention should be paid to this area for PCBs.展开更多
Using daily NCEP/NCAR reanalysis dataset and observation rainfall data in China for the 1971-2000 period, a subtropical summer monsoon index has been defined by meridional moisture transport of the total atmosphere co...Using daily NCEP/NCAR reanalysis dataset and observation rainfall data in China for the 1971-2000 period, a subtropical summer monsoon index has been defined by meridional moisture transport of the total atmosphere column. Results show that the subtropical summer monsoon index defined by the difference of meridional moisture transport between South China and North China can be used to describe the intensity of the subtropical summer monsoon. High (low) index is corresponding to strong (weak) subtropical summer monsoon. And the new index is well related to the summer rainfall over the middle and lower reaches of Yangtze River. In addition, the convergence of moisture transport from the west Pacific via the South China Sea and that from the North China may be responsible for the anomalously excessive summer rainfall over the middle and lower reaches of Yangtze River.展开更多
Cocoon samples were collected from fifty-two mulberry gardens with high, intermediate, and low silkworm cocoon productivities in the lower-middle reaches of the Yangtze River in the six China’s provinces of Jiangsu, ...Cocoon samples were collected from fifty-two mulberry gardens with high, intermediate, and low silkworm cocoon productivities in the lower-middle reaches of the Yangtze River in the six China’s provinces of Jiangsu, Jiangxi, Anhui, Fujian, Hunan, and Hubei to determine the transformation efficiency of S from mulberry leaves to silkworm cocoons, and to evaluate the sulfur cycle (uptake and output) in the mulberry leaf-silkworm cocoon system with typical mulberry gardens in the lower-middle reaches of the Yangtze River in China. The transformation efficiency of sulfur (TES) from mulberry leaves into silkworm cocoons in the high-productivity mulberry gardens was significantly lower (P < 0.05) than that in the low-productivity gardens. For the high-productivity mulberry gardens the TES from mulberry leaves into the cocoon shells was significantly higher (P < 0.05) than that for low-yield mulberry gardens. Producing 1 kg dry cocoon in mulberry gardens required uptake of about 20 g S, however 1 kg of dry cocoon only removed about 4 g S. Therefore, recycling of these organic wastes with silkworm cultivation was important for sulfur balances.展开更多
The sex-related molecular marker of the Yangtze finless porpoise was screened using Amplified Fragment Length Polymorphism (AFLP) technique combined with the bulked segregant analysis. Totally 36 AFLP primer combinati...The sex-related molecular marker of the Yangtze finless porpoise was screened using Amplified Fragment Length Polymorphism (AFLP) technique combined with the bulked segregant analysis. Totally 36 AFLP primer combinations were used to detect the genome DNA bulks of the female and male porpoises, and one sex-related AFLP marker was finally obtained. The marker can be applied to sex identification, and provides a base for further cloning of sex-related genes and analyzing of Y chromosome haplotypes of the Yangtze finless porpoise.展开更多
Basic climatic characteristics are analyzed concerning the precipitation anomalies in raining seasons over regions south of the Changjiang River (the Yangtze). It finds that the regions are the earliest in eastern Chi...Basic climatic characteristics are analyzed concerning the precipitation anomalies in raining seasons over regions south of the Changjiang River (the Yangtze). It finds that the regions are the earliest in eastern China where raining seasons begin and end. Precipitation there tends to decrease over the past 50 years. Waters bounded by 9(S -1(S, 121(E - 129(E are the key zones of SST anomalies that affect the precipitation in these regions over May ~ July in preceding years. Long-term air-sea interactions make it possible for preceding SST anomalies to affect the general circulation that come afterwards, causing precipitation anomalies in the raining seasons in regions south of the Changjiang River in subsequent years.展开更多
The upper Yangtze River region is one of the most frequent debris flow areas in China. The study area contains a cascade of six large hydropower stations located along the river with total capacity of more than 70 mil...The upper Yangtze River region is one of the most frequent debris flow areas in China. The study area contains a cascade of six large hydropower stations located along the river with total capacity of more than 70 million kilowatts. The purpose of the study was to determine potential and dynamic differences in debris flow susceptibility and intensity with regard to seasonal monsoon events. We analyzed this region's debris flow history by examining the effective peak acceleration of antecedent earthquakes,the impacts of antecedent droughts, the combined effects of earthquakes and droughts, with regard to topography, precipitation, and loose solid material conditions. Based on these factors, we developed a debris flow susceptibility map. Results indicate that the entire debris flow susceptibility area is 167,500 km^2, of which 26,800 km^2 falls within the high susceptibility area, with 60,900 km^2 in medium and 79,800 km^2 are in low susceptibility areas. Three of the six large hydropower stations are located within the areas with high risk of debris flows. The synthetic zonation map of debris flow susceptibility for the study area corresponds with both the investigation data and actual distribution of debris flows. The results of debris flow susceptibility provide base-line data for mitigating, assessing, controlling and monitoring of debris flows hazards.展开更多
T he estuary and coast is an area where the land and the sea interact and a place in which human beings frequently move about so that understanding and controlling the change and development modes of the coastal landf...T he estuary and coast is an area where the land and the sea interact and a place in which human beings frequently move about so that understanding and controlling the change and development modes of the coastal landform plays a vital part in exploiting and protecting coastal resources. A model is the generalization and abstraction of objective things. This paper summarizes four methods for the landform development of the tidal shore and underwater delta, mainly discusses the model’s structural elements, and presents their specific application on the basis of the authors’ case study. With the application of the profile model, the dynamic change of coastal landform can be clearly seen by contrasting the different profiles of different years. Through the shrinking, expanding and transformation of the isobath, plane model is used to study the macro-change of the shoal and the coastal landform. Speed model is an efficient means to analyze the trend of erosion and deposition and the local change in a great area of the sea. Statistical survey model is a static analysis, which can be used to establish the relationship between the erosion and deposition of the shoal and the altitude and slope of survey spot.展开更多
With the enhanced warming and acidification of global ocean, whether and to what extent the naturally-weathered flu- vial sediment into the sea can release elements and thus influence the geochemical process and ecosy...With the enhanced warming and acidification of global ocean, whether and to what extent the naturally-weathered flu- vial sediment into the sea can release elements and thus influence the geochemical process and ecosystem of global ocean remain to be resolved. In this contribution, an experimental study was carried out to examine the release rates of major elements (Ca, K, Mg and AI) from the surface sediments in the Changjiang (Yangtze River) Estuary under the pH values of 4.0, 6.0 and 7.0. The two stud- ied sediments consist primarily of quartz, plagioclase, calcite and clay minerals, with the BET (Brunauer, Emmett and Teller) surface areas of 61.7m2g-1 and 23.1 m2g-1. Major elements of Ca, K, Mg and A1 show different release rates under different solution pH values. With the decreasing solution pH, the release rates of Ca and K increase obviously, while the release rates of Mg and A1 in- crease with the initial solution pH varying from 6.0 to 7.0. The different release rates of these elements are closely related to the original mineral composition of the sediments and the reaction kinetics. Based on the experimental observation, quartz and clay min- erals that have low dissolution rates may dominate the major element release to the aqueous phase. This study reveals that the en- hancing ocean acidification could cause considerable release of major elements from natural terrigenous sediments into the ambient marine environment, which has to be considered carefully in the future study on global change.展开更多
This article focuses on the hydrocracking technology for upgrading the quality of tail oil and the first commercial application of the RN-32V/RHC- 1 catalysts in the 1.0 Mt/a hydrocracker at the Yangzi Petrochemical C...This article focuses on the hydrocracking technology for upgrading the quality of tail oil and the first commercial application of the RN-32V/RHC- 1 catalysts in the 1.0 Mt/a hydrocracker at the Yangzi Petrochemical Company, which was started up successfully in September 2008. One month after start-up of the hydrocracking unit, an evaluation opera- tion has been conducted fbr assessing the catalysts performance. The technical calibration results showed that the RN- 32V/RHC-1 catalysts had high activity, and the product yield distribution was reasonable. The hydrocracker can provide abundant feedstocks for the downstream aromatic production unit and ethylene production unit.展开更多
文摘《中国扬子区兰多维列统特列奇阶及其与英国的对比》一书(陈旭和戎嘉余,1996)有以下结论:①将回星哨组、茅山组、西坑组等的层位归属于特列奇阶上部;②将回星哨组、茅山组及其相当地层与英国特列奇阶对比;③将扬子区特列奇阶的顶界置于回星哨组、茅山组及其相当地层之顶;④将回星哨组、茅山组、西坑组等地层资料编制的古地理图称为特列奇期晚期古地理图;⑤将回星哨组、茅山组、西坑组等地层与上覆中泥盆统—中二叠统之间的不整合面代表的上升运动,称为“特列奇期的扬子上升”。笔者等依据多年对扬子地台志留纪地层剖面的实地考察和近数十年来扬子区坟头组中—上部、茅山组、回星哨组、小溪峪组、西坑组等地层中文洛克世、拉德洛世、普里多利世早期古生物化石的发现,认为:①回星哨组、小溪峪组、茅山组、西坑组等的层位是文洛克统—普里多利统;②回星哨组、小溪峪组等大致与英国的文洛克统—普里多利统对比;③回星哨组、小溪峪组、茅山组的顶界是文洛克统—普里多利统剥蚀后残留的层位随地而异的顶界;④根据回星哨组、西坑组、茅山组等地层资料编制的古地理图应是文洛克世—普里多利世古地理图;⑤“扬子地台整个上升”(Huang T K,1945)的时代是志留纪末期,没有“特列奇期的扬子上升”。特提出商榷。上述这些地层时代的解决,对扬子区志留系4统层序的建立具有重要意义,而且也为中国扬子区与英国命名剖面志留系的对比以及中国南方早古生代加里东运动最后一幕时代的再次确定提供了地层学和古生物方面的依据。
文摘Aim To investigate the chemical composition of Ranunculus sieboldii Miq..Methods Repeated column chromatography over silica gel, polyamide and RP-18 followed by gelfiltration on sephadex LH-20 were used to isolate chemical constituents, and their structures wereelucidated by extensive spectroscopic methods (UV, IR, MS, ~1H NMR, ^(13)C NMR) including 2D NMR(COSY, HMQC, HMBC, NOESY) techniques and by direct comparing spectral data with those reported inliterature. Results Five flavonoid glycosides named apigenin-4'-O-α-L-rhamnopyranoside (1),apigenin-7-O-β-D-glucopyranosyl-4'-O-α-L-rhamnopyranoside (2), apigenin-8-C-α-L-arabinopyranoside(3), apigenin-8-C-β-D-ga-lactopyranoside (4) , tricin-7-O-β-D-glucopyranoside (5), together withtricin (6), luteolin (7), scopoletin (8), esculetin (9), scoparone (10), ferulic acid (11),protocatechuic acid (12) , and tematolide (13) were isolated from the 95% etha-nolic extract of itswhole plant, and their cytotoxic activities were preliminarily tested. Conclusion Compounds 1-12were obtained from this genus and compound 13 from this species for the first time. Furthermore,compound 1 was for the first time isolated from nature while the ^(13)C NMR data of compounds 2 and3 are reported for the first time. The bioassay revealed that compound 1 was active against BEL-7407and A549 cell lines (IC_(45) 43, 77 μg·mL^(-1)), 8 and 10 showed inhibitory activities on KB celllines (IC_(50) 78, 44 μg·mL^(-1)) and HL-60 cell lines (Ic_(50) 85, 85 μg·mL^(-1)), while 7exerted moderate cytotoxic activities on KB, BFL-7407, A549 and HL-60 cell lines with their IC_(50)being 51, 55, 44 and 10 μg·mL^(-1) , respectively.
基金the National Natural Science Foundation of China (No. 30270213 and 30470244)a grant of Special Scholar Foundation from Anhui Province (No. 04043049)the Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province.
文摘The polymorphism of MHC class II B gene in 14 Chinese alligators was analyzed, which came from three different areas: a wild population from Xuancheng, Anhui, a captive population from Changxing, Zhejiang, and a captive population from Anhui Research Center for Reproduction of Chinese Alligators. The gene fragment was amplified using a pair of specific primers designed from the MHC gene sequence of the spectacled caiman. A total of 34 sequence haplotypes of exon 3 were detected in the sampled Chinese alligators. The numbers of haplotypes of the 3 Chinese alligator populations were 15, 10, and 9, respectively. The overall estimation of the MHC polymorphism in the Chinese alligator population was higher than those in mammals and in cypdnid fish, The rates of nonsynonymous substitutions (dN) occurred at a significantly lower frequency than that of synonymous substitutions (ds), which were not consistent with the common rule. This result might suggest that the polymorphism of exon 3 seemed not to be maintained by the balancing selection. The neutrality test of Tajima excluded the null hypothesis that the polymorphism of exon 3 was generated by a random drift, and the fact that D = -0.401 indicated an excess of rare mutations in the Chinese alligator. The nucleotide diversity of the sequences and the phylogenetic relations were also analyzed, and the results suggested that there was no significant difference in genetic diversity among the 3 populations of Chinese alligator.
基金The National Natural Science Foundation of China (30770312)the Fund for Releasing Chinese Alligators by the State Forestry Administration+1 种基金the Fund for Leading Scientist of Science and Technology in Anhuithe foundation of Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province
文摘The Chinese alligator (Alligator sinensis) is a critically endangered species in China. Wild populations of Chinese alligator are on the edge of extinction. Through a release program, some captive-bred alligators will be selected and released into the wild to supplement and renew natural populations. The purpose of this study was to provide data to select healthy individuals for release. Through bacteriological and molecular identification, six different genera, eight species and an unclassified bacterium were identified in 13 bacterial strains, which were isolated from the cloaca of 25 Chinese alligators. One genus and four species were identified in eight bacterial strains, which were isolated from the water where the alligators live. According to the analysis, except for the unclassified bacterium, the other bacteria from the cloaca were not pathogenic and were different from the bacteria isolated from the water. Thus, it was concluded that the 24 Chinese alligators were healthy, and could be selected to be released into the wild. As subject AS 12 was identified carrying an unclassified bacteria, of which the characteristics were unknown, it was suggested that the AS 12 individual not be released.
基金Project supported by the National Key Basic Research Support Foundation (NKBRSF) of China (No. G1999011810) the National Natural Science Foundation of China (No. 49971039).
文摘The reasons for the Yangtze River flood calamity in 1998 are briefly introduced. The authors believe that using a 'soil reservoir' concept is an important means to help control flooding of the Yangtze River.A 'soil reservoir' has a large potential storage capacity and its water can be rapidly 'discharged' into the underground water in a timely fashion. The eroded, infertile soils of the Yangtze River Watershed are currently an obstacle to efficient operation of the 'soil reservoir'. The storage capacity of this 'soil reservoir'has been severely hampered due to intensive soil erosion and the formation of soil crusts. Therefore, possible measures to control floods in the Yangtze River Watershed include: rehabilitating the vegetation to preserve soil and water on the eroded infertile soils, enhancing infiltration of the different soil types, and utilizing the large 'soil reservoir' of the upper reaches of the Yangtze River.
基金the result of the project(No.400610o6)funded by the National Natural Science Foundation of China.
文摘Land use/land cover change (LUCC) is a focus of the research of global environmental changes. The middle and upper reaches of the Yangtze River, which are the most ecologically fragile mountainous area in China as well as one of the areas in China with most notable LUCC, have been on the Chinese Government's list of priority areas for ecological restoration. This paper is to reveal the trend of LUCC and the ecological degradation arising from it, and to provide a basis for the future sustainable use of land resources in the region based on a detailed analysis of Yiliang County. Based on the county's land use/cover maps in 1960, 1980 and 2000 drawn with the aid of aerial photograph interpretation, field investigation and GIS based spatial-temporal data analysis, LUCC during 1960~2000 period and the ecological degradation arising from it were analyzed. Using the Markv model, the paper brings out a forecast of what the county's LUCC would be like if the county's current land use continues, as well as the reasons and countermeasures for restoring degraded ecosystems.
基金Supported by the National Basic Research Program of China(973 Program)(No.2010CB428903)the National Marine Public Welfare Research Project of China(Nos.201505004-3,201305043)+1 种基金the Scientific Research Fund of the Second Institute of Oceanography,SOA(No.JG1312)the National Special Fund of Chinese Offshore Investigation and Assessment(No.908-01-ST04)
文摘To assess the effects of hypoxia, macrobenthic communities along an estuarine gradient of the Changjiang estuary and adjacent continental shelf were analyzed. This revealed spatial variations in the communities and relationships with environmental variables during periods of reduced dissolved oxygen (DO) concentration in summer. Statistical analyses revealed significant differences in macrobenthic community composition among the three zones: estuarine zone (EZ), mildly hypoxic zone (MHZ) in the continental shelf, and norrnoxic zone (NZ) in the continental shelf(Global R=0.206, P=0.002). Pairwise tests showed that the macrobenthic community composition of the EZ was significantly different from the MHZ (pairwise test R=0.305, P=0.001) and the NZ (pairwise test R=0.259, P=-0.001). There was no significant difference in macrobenthic communities between the MHZ and the NZ (pairwise test R=0.062, P=-0.114). The taxa included small and typically opportunistic polychaetes, which made the greatest contribution to the dissimilarity between the zones. The effects of mild hypoxia on the macrobenthic communities are a result not only of reduced DO concentration but also of differences in environmental variables such as temperature, salinity, and nutrient concentrations caused by stratification.
基金supported by the National Natural Science Fund of China (No.49871068 and No.40131020)
文摘PCBs pollutants are measured on tidal-flat sediments of Yangtze estuary by a high resolution capillary column gas chromatography ( HP6890 ) equipped with an 63Ni electron capture detector ( ECD ). The concentration tendency of PCBs is Phragmites zone > Scirpus zone > bare mudflats. There are linear relations between PCBs and TOC and > 63μm grain size percentage ( in volume ). The low chlorinated congeners may be more important than the high chlorinated congeners in this area. PCBs prefer to accumulate in the sediments near sewage outlets and Phragmites zone. The sediments’ PCBs pollution ( 10.7 ~ 28.6 ng/g, dry weight ) in the Yangtze estuary tidal-flat is less serious than that of the most of other areas in the world .But the detected ratio is 100%, even the Jiuduansha shoal has detected PCBs, so much attention should be paid to this area for PCBs.
基金Research on Interdecadal Variation of the Progression of Subtropical Summer Monsoon inEast Asia, a specialized project of China Meteorological AdministrationResearch on Subtropical Monsoon, aspecialized project of Shanghai Meteorological Bureau
文摘Using daily NCEP/NCAR reanalysis dataset and observation rainfall data in China for the 1971-2000 period, a subtropical summer monsoon index has been defined by meridional moisture transport of the total atmosphere column. Results show that the subtropical summer monsoon index defined by the difference of meridional moisture transport between South China and North China can be used to describe the intensity of the subtropical summer monsoon. High (low) index is corresponding to strong (weak) subtropical summer monsoon. And the new index is well related to the summer rainfall over the middle and lower reaches of Yangtze River. In addition, the convergence of moisture transport from the west Pacific via the South China Sea and that from the North China may be responsible for the anomalously excessive summer rainfall over the middle and lower reaches of Yangtze River.
基金Project financially supported by the Postdoctoral Fund of People's Government of Jiangsu Province, China the FernzSulFer Works Inc., Irricana, Canada and The Sulphur Institute, USA (No. 2500-0007).
文摘Cocoon samples were collected from fifty-two mulberry gardens with high, intermediate, and low silkworm cocoon productivities in the lower-middle reaches of the Yangtze River in the six China’s provinces of Jiangsu, Jiangxi, Anhui, Fujian, Hunan, and Hubei to determine the transformation efficiency of S from mulberry leaves to silkworm cocoons, and to evaluate the sulfur cycle (uptake and output) in the mulberry leaf-silkworm cocoon system with typical mulberry gardens in the lower-middle reaches of the Yangtze River in China. The transformation efficiency of sulfur (TES) from mulberry leaves into silkworm cocoons in the high-productivity mulberry gardens was significantly lower (P < 0.05) than that in the low-productivity gardens. For the high-productivity mulberry gardens the TES from mulberry leaves into the cocoon shells was significantly higher (P < 0.05) than that for low-yield mulberry gardens. Producing 1 kg dry cocoon in mulberry gardens required uptake of about 20 g S, however 1 kg of dry cocoon only removed about 4 g S. Therefore, recycling of these organic wastes with silkworm cultivation was important for sulfur balances.
文摘The sex-related molecular marker of the Yangtze finless porpoise was screened using Amplified Fragment Length Polymorphism (AFLP) technique combined with the bulked segregant analysis. Totally 36 AFLP primer combinations were used to detect the genome DNA bulks of the female and male porpoises, and one sex-related AFLP marker was finally obtained. The marker can be applied to sex identification, and provides a base for further cloning of sex-related genes and analyzing of Y chromosome haplotypes of the Yangtze finless porpoise.
基金Interannual and Interdecadal Variation Laws Governing the Mei-yu in the Changjiang-Huanhe Rivers valley Key Foundation Project in National Natural Science Foundation (40233037) Research on the Interactions between the South Asia High and Asia Monsoon a
文摘Basic climatic characteristics are analyzed concerning the precipitation anomalies in raining seasons over regions south of the Changjiang River (the Yangtze). It finds that the regions are the earliest in eastern China where raining seasons begin and end. Precipitation there tends to decrease over the past 50 years. Waters bounded by 9(S -1(S, 121(E - 129(E are the key zones of SST anomalies that affect the precipitation in these regions over May ~ July in preceding years. Long-term air-sea interactions make it possible for preceding SST anomalies to affect the general circulation that come afterwards, causing precipitation anomalies in the raining seasons in regions south of the Changjiang River in subsequent years.
基金supported by the National Natural Science Foundation of China (Grant No. 41661134012 and 41501012)the Taiwan Youth Visiting Scholar Fellowship of Chinese Academy of Sciences (Grant No. 2015TW2ZB0001)
文摘The upper Yangtze River region is one of the most frequent debris flow areas in China. The study area contains a cascade of six large hydropower stations located along the river with total capacity of more than 70 million kilowatts. The purpose of the study was to determine potential and dynamic differences in debris flow susceptibility and intensity with regard to seasonal monsoon events. We analyzed this region's debris flow history by examining the effective peak acceleration of antecedent earthquakes,the impacts of antecedent droughts, the combined effects of earthquakes and droughts, with regard to topography, precipitation, and loose solid material conditions. Based on these factors, we developed a debris flow susceptibility map. Results indicate that the entire debris flow susceptibility area is 167,500 km^2, of which 26,800 km^2 falls within the high susceptibility area, with 60,900 km^2 in medium and 79,800 km^2 are in low susceptibility areas. Three of the six large hydropower stations are located within the areas with high risk of debris flows. The synthetic zonation map of debris flow susceptibility for the study area corresponds with both the investigation data and actual distribution of debris flows. The results of debris flow susceptibility provide base-line data for mitigating, assessing, controlling and monitoring of debris flows hazards.
基金supported by the National Great Science Project(2002CB412407)the National Science Foundation(40076027).
文摘T he estuary and coast is an area where the land and the sea interact and a place in which human beings frequently move about so that understanding and controlling the change and development modes of the coastal landform plays a vital part in exploiting and protecting coastal resources. A model is the generalization and abstraction of objective things. This paper summarizes four methods for the landform development of the tidal shore and underwater delta, mainly discusses the model’s structural elements, and presents their specific application on the basis of the authors’ case study. With the application of the profile model, the dynamic change of coastal landform can be clearly seen by contrasting the different profiles of different years. Through the shrinking, expanding and transformation of the isobath, plane model is used to study the macro-change of the shoal and the coastal landform. Speed model is an efficient means to analyze the trend of erosion and deposition and the local change in a great area of the sea. Statistical survey model is a static analysis, which can be used to establish the relationship between the erosion and deposition of the shoal and the altitude and slope of survey spot.
基金supported by research funds awarded by the National Natural Science Foundation of China (Grant Nos. 41225020 and 41376049)Continental Shelf Drilling Program (Grant No. GZH201100202)China Geologic Survey (Grant No. GZH201100203)
文摘With the enhanced warming and acidification of global ocean, whether and to what extent the naturally-weathered flu- vial sediment into the sea can release elements and thus influence the geochemical process and ecosystem of global ocean remain to be resolved. In this contribution, an experimental study was carried out to examine the release rates of major elements (Ca, K, Mg and AI) from the surface sediments in the Changjiang (Yangtze River) Estuary under the pH values of 4.0, 6.0 and 7.0. The two stud- ied sediments consist primarily of quartz, plagioclase, calcite and clay minerals, with the BET (Brunauer, Emmett and Teller) surface areas of 61.7m2g-1 and 23.1 m2g-1. Major elements of Ca, K, Mg and A1 show different release rates under different solution pH values. With the decreasing solution pH, the release rates of Ca and K increase obviously, while the release rates of Mg and A1 in- crease with the initial solution pH varying from 6.0 to 7.0. The different release rates of these elements are closely related to the original mineral composition of the sediments and the reaction kinetics. Based on the experimental observation, quartz and clay min- erals that have low dissolution rates may dominate the major element release to the aqueous phase. This study reveals that the en- hancing ocean acidification could cause considerable release of major elements from natural terrigenous sediments into the ambient marine environment, which has to be considered carefully in the future study on global change.
文摘This article focuses on the hydrocracking technology for upgrading the quality of tail oil and the first commercial application of the RN-32V/RHC- 1 catalysts in the 1.0 Mt/a hydrocracker at the Yangzi Petrochemical Company, which was started up successfully in September 2008. One month after start-up of the hydrocracking unit, an evaluation opera- tion has been conducted fbr assessing the catalysts performance. The technical calibration results showed that the RN- 32V/RHC-1 catalysts had high activity, and the product yield distribution was reasonable. The hydrocracker can provide abundant feedstocks for the downstream aromatic production unit and ethylene production unit.