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北牛南养之牛焦虫病诊治初报 被引量:2
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作者 蒋开端 姚显文 《山地农业生物学报》 2007年第2期183-185,共3页
关键词 北牛 南养 焦虫病 药物治疗 防治技术
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Cell Apoptosis Induced by Oligosaccharide in Suspension Cultures of Taxus chinensis 被引量:2
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作者 李春 元英进 +3 位作者 马忠海 胡宗定 孙安慈 胡昌序 《Acta Botanica Sinica》 CSCD 2002年第5期598-602,共5页
Taxol production of Taxus chinensis (Pilger) Rehd. var. mairei (Lemee et Lévl.) Cheng et L. K. Fu induced by oligosaccharide from Fusarium oxysporum f. vasinfectum (Atkinson) Snyder et Hansen was ... Taxol production of Taxus chinensis (Pilger) Rehd. var. mairei (Lemee et Lévl.) Cheng et L. K. Fu induced by oligosaccharide from Fusarium oxysporum f. vasinfectum (Atkinson) Snyder et Hansen was studied in suspension cultures, and it was found that oligosaccharide triggered cell apoptosis. Under transmission electron microscope the following morphological changes were observed: cell shrinkage, condensation of cytoplasm, nuclear fragmentation, and the increase of high electron density bodies in vacuole in great quantity. In oligosaccharide_treated cells, agarose gel electrophoresis revealed that DNA was digested into oligonucleosomal fragments that were times of 200 bp appearing as DNA ladders. Control cells were in normal physiological state, they were intact, abundant in organelle and with integral nucleus DNA, and the rate of taxol biosynthesis in these cells was very low. After the oligosaccharide to the culture system, the defense system of cells was elicited and the secondary metabolism was strengthened, i.e. phenolics were accumulated in the medium, the activity of polyphenol oxidase (PPO) was increased quickly and secondary wall of cells was thickened. The activity of L _phenylalanine ammonia lyase (PAL), the critical enzyme of the phenylpropanoid pathway, was increased promptly 1 h after elicitation. The rate of taxol production was improved sharply and the maximal taxol concentration at 72 h was six times that of control. Appearance of cell apoptosis was accompanied with the highest concentration of taxol in suspension cultures. 展开更多
关键词 fungal oligosaccharide Taxus chinensis APOPTOSIS secondary metabolism TAXOL
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Responses of Picoplankton to Nutrient Perturbation in the South China Sea, with Special Reference to the Coast-wards Distribution of Prochlorococcus 被引量:3
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作者 焦念志 杨燕辉 +2 位作者 Hiroshi KOSHIKAWA Shigeki HARADA Masataka WATANABE 《Acta Botanica Sinica》 CSCD 2002年第6期731-739,共9页
Responses of Prochlorococcus (Pro), Synechococcus (Syn), pico-eukaryotes (Euk) and heterotrophic bacteria (Bact) in pelagic marine ecosystems to external nutrient perturbations were examined using nitrogen- (N), phosp... Responses of Prochlorococcus (Pro), Synechococcus (Syn), pico-eukaryotes (Euk) and heterotrophic bacteria (Bact) in pelagic marine ecosystems to external nutrient perturbations were examined using nitrogen- (N), phosphorus- (P), iron- (Fe), and cobalt- (Co) enriched incubations in the South China Sea in November 1997. Variations in abundance of the 4 groups of microorganism and cellular pigment content of the autotrophs during incubation were followed by flow-cytometric measurements for seven days. During the incubation, Syn and Euk showed a relatively higher demand on Fe and N, while Pro required higher levels of Co and P. The Fe was inadequate for all the organisms in the deep euphotic zone (75 m) of the study area. The experimental results also implied that biological interaction among the organisms played a role in the community structure shift during the incubation. It seemed that besides the effects of temperature, there are some other physical and chemical limitations as well as impacts from biological interactions on Pro distribution in coast waters. 展开更多
关键词 PROCHLOROCOCCUS PICOPLANKTON NUTRIENTS iron cobalt South China Sea
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Chemical Constituents of the Suspension Cell Cultures of Maytenus hookeri 被引量:7
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作者 鲁春华 张建新 +1 位作者 甘烦远 沈月毛 《Acta Botanica Sinica》 CSCD 2002年第5期603-610,共8页
Suspension cell cultures of Maytenus hookeri Loos. (Celastraceae) in SH media were established from the calli induced from the leaves and young steins of M. hookeri on MS media with the supplement of 2 mg/L 2,4-D and ... Suspension cell cultures of Maytenus hookeri Loos. (Celastraceae) in SH media were established from the calli induced from the leaves and young steins of M. hookeri on MS media with the supplement of 2 mg/L 2,4-D and 0.1 mg/L KIN (kinetin). Ethyl acetate extract of the cultures showed inhibitory activities against Penicillium avellaneum UC-4376 which was sensitive to maytansinoids. Exhaustive isolation of natural products from a large scale of suspension cell cultures did not yield maytansine instead of affording nine compounds including one novel triterpenoid, named 2, 3-diacetoxyl maytenusone (1), and eight known ones including squalene (2), beta-sitosterol (3), 2', 3', 4-triacetyl-sitoindoside I (4), salaspermic acid (5), maytenonic acid (6), 2alpha-hydroxy-maytenonic acid (7), 6, 11,12-trihydroxy-8, 11, 13-abietrien-7-one (8) and 11, 12-dihydroxy-8, 11, 13-abietatrien-7-one (9) elucidated on the basis of 1D and 2D NMR data. The H-1-NMR and C-13-NMR assignments were made for 1, 5, 6 and 7, while the C-13-NMR assignments for 5 and 6 were revised. The chemical results suggested that the suspension cell cultures of M. hookeri did not produce maytansinoids under the reported experiment conditions. 展开更多
关键词 Maytenus hookeri CELASTRACEAE suspension cell cultures maytansine 2 3-diacetoxyl maytenusone
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Productions of Taxol and Related Taxanes by Cell Suspension Cultures of Taxus yunnanensis 被引量:10
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作者 胡益明 甘烦远 +2 位作者 鲁春华 丁鸿珊 沈月毛 《Acta Botanica Sinica》 CSCD 2003年第3期373-378,共6页
A high taxol yield cell line of Taxus yunnanensis Cheng et L. K. Fu keeps a high taxol_producing level after successive subcultures for more than eight years. In this study, eight taxanes were isolated from the su... A high taxol yield cell line of Taxus yunnanensis Cheng et L. K. Fu keeps a high taxol_producing level after successive subcultures for more than eight years. In this study, eight taxanes were isolated from the suspension cell cultures of this cell line. Based on NMR and MS analyses, and comparison with literature data and standards, their structures were determined to be 2α,5α,10β_triacetoxy_14β_propionyloxy_4(20),11_taxadiene (1), 2α,5α,10β_triacetoxy_14β_(2′_methyl)_butyryloxy_4(20),11_taxadiene (2), 2α,5α,10β_14β_tetra_acetoxy_4 (20),11_taxadiene (3, taxuyunnanine C), 2α,5α,10β_triacetoxy_14β_(2′_methyl_3′_hydroxy)_butyryloxy_4(20),11_taxadiene (4, yunnanxane) and its 3′_epimer (5), baccatin Ⅳ (6), baccatin Ⅲ (7) and taxol (8), respectively. Among those compounds, 3, 5, 6 and 7 were reported to be isolated from the suspension cell cultures of T. yunnanensis for the first time. TLC and HPLC analyses indicated that the chemical constituents of the culture solution were similar to those of cultured cells. Moreover, the highest taxol content of this cell line reached 0.3% and the cell line could be applied for a large_scale culture. 展开更多
关键词 Taxus yunnanensis cell suspension cultures TAXOL TAXANES
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Biological Characteristics and Rumen Microorganisms of Gayal(Bos frontalis)in Yunnan Province 被引量:3
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作者 杨舒黎 苟潇 +3 位作者 冷静 毛华明 邓卫东 吴锡川 《Agricultural Science & Technology》 CAS 2011年第8期1234-1237,共4页
[Objective]The paper was to provide reference for further study and development of gayal(Bos frontalis).[Method]According to the research status at home and abroad,the biological characteristics and rumen microorgan... [Objective]The paper was to provide reference for further study and development of gayal(Bos frontalis).[Method]According to the research status at home and abroad,the biological characteristics and rumen microorganisms of gayal in Yunnan Province was studied.[Result]Gayal in Yunnan had typical body form and very good meat production performance,its muscle fiber diameter was significantly less than other kinds of cattle;the water holding ratio,muscle tenderness and muscle succulency were significantly higher than others;its amount,shape and structure of chromosome were different from yellow cattle(Bos taurus)and wild cattle(Bos gaurus),and the amounts of those chromosomes(2n)were 58,60 and 56,respectively.It could create hybrid with yellow cattle;the gayal's special diet was bamboo,its in vitro dry matter digestibility(IVDMD)on various crude forage was significantly higher than yellow cattle in Yunnan;the viable bacteria and cellulolytic bacteria in rumen were 4.51×109 and 1.63×109 CFU/ml,which was significantly higher than yellow cattle in Yunnan,its dominant bacteria in rumen mainly was cellulolytic bacteria.[Conclusion]Gayal not only had high academic value,but also had a great development value. 展开更多
关键词 Gayal(Bos frontalis)in Yunnan Meat quality Genetic diversity Nutrient digestibility Rumen microorganism
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Trophic interactions, ecosystem structure and function in the southern Yellow Sea 被引量:3
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作者 林群 金显仕 张波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期46-58,共13页
The southem Yellow Sea is an important fishing ground, providing abundant fishery resources. However, overfishing and climate change have caused a decline in the resource and damaged the ecosystem. We developed an eco... The southem Yellow Sea is an important fishing ground, providing abundant fishery resources. However, overfishing and climate change have caused a decline in the resource and damaged the ecosystem. We developed an ecosystem model to analyze the trophic interactions and ecosystem structure and function to guide sustainable development of the ecosystem. Atrophic mass-balance model of the southern Yellow Sea during 2000-2001 was constructed using Ecopath with Ecosim software. We defined 22 important functional groups and studied their diet composition. The trophic levels of fish, shrimp, crabs, and cephalopods were between 2.78 and 4.39, and the mean trophic level of the fisheries was 3.24. The trophic flows within the food web occurred primarily in the lower trophic levels. The mean trophic transfer efficiency was 8.1%, of which 7.1% was from primary producers and 9.3% was from detritus within the ecosystem. The transfer efficiency between trophic levels II to III to IV to V to 〉V was 5.0%, 5.7%, 18.5%, and 19.7%-20.4%, respectively. Of the total flow, phytoplankton contributed 61% and detritus contributed 39%. Fishing is defined as a top predator within the ecosystem, and has a negative impact on most commercial species. Moreover, the ecosystem had a high gross efficiency of the fishery and a high value of primary production required to sustain the fishery. Together, our data suggest there is high fishing pressure in the southern Yellow Sea. Based on analysis of Odum's ecological parameters, this ecosystem was at an immature stage. Our results provide some insights into the structure and development of this ecosystem. 展开更多
关键词 ECOPATH trophic interactions ecosystem structure FISHERIES the southern Yellow Sea
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Planting Performance of Pennisetum purpureum Schumab cv.Purple in the Southern Region of China 被引量:1
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作者 易显凤 赖志强 +4 位作者 姚娜 蔡小艳 韦锦益 赖大伟 梁永良 《Agricultural Science & Technology》 CAS 2016年第3期667-671,共5页
[Objective] The present experiment was conducted to investigate the yield,adaptability and quality characteristics of Pennisetum purpureum Schumach cv. Purple to provide reference for the certification and development... [Objective] The present experiment was conducted to investigate the yield,adaptability and quality characteristics of Pennisetum purpureum Schumach cv. Purple to provide reference for the certification and development of new varieties.[Method] With P. purpureum Schumab cv. Purple as experimental material, the variety comparison tests were conducted in Nanning, Lingyun, and Tiandeng in Guangxi from 2007 to 2009, and variety regional trials were conducted in Danzhou of Hainan, Fuzhou of Fujian and Zhanjiang of Guangdong from 2011 to 2013. Its comprehensive characters of plant height, hay yield, stem-leaf ratio and nutritional components were determined, and were compared with those of P. purpureum × P.americanum cv. Reyan No.4 and P. purpureum Schum cv. Guiminyin. [Result] The average height of P. purpureum Schumach cv. Purple was 706.54 cm, which was5.92% and 8.44% lower than that of P. purpureum × P. americanum cv. Reyan No.4 and P. purpureum Schum cv. Guiminyin, respectively. The average hay yield of P. purpureum Schumach cv. Purple was 32.74 t/ha in Nanning, Lingyun, and Tiandeng of Guangxi from 2007 to 2009, and 22.41 t/ha in Danzhou of Hainan, Fuzhou of Fujian and Zhanjiang of Guangdong from 2011 to 2013. Although its hay yield was lower than two control varieties, the difference was not significant(P 0.05).The stem-leaf ratio of P. purpureum Schumach cv. Purple was 0.98:1. Moreover,the analysis on the nutritional components of dry matter showed that compared with P. purpureum × P. americanum cv. Reyan No.4 and P. purpureum Schum cv.Guiminvin, the crude fiber of P. purpureum Schumab cv. Purple was decreased by4.76% and 2.78%, respectively; the neutral detergent fiber decreased by 5.07% and2.22%, respectively; the acid detergent fiber was decreased by 2.54% and 1.99%,respectively; the crude fat was increased by 64.29% and 43.75%, respectively; the calcium content was increased by 28.00% and 33.33%, respectively; the phosphorus content was increased by 9.68% and 22.73%, respectively; the total content of amino acid was increased by 43.23% and 68.41%, respectively; the anthocyanin content of leaf was increased by 400.00% and 216.90%, respectively(P 0.05).[Conclusion] P. purpureum Schumach cv. Purple is a new high-quality forage variety with wide adaptability, high yield, rich nutrient and good palatability, which is appropriate for comprehensive exploitation and application in the southern region of China. 展开更多
关键词 P.purpureum Schumab cv.Purple Plant height Hay yield Stem-leaf ratio Nutritional component Southern region of China
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The Arabidopsis PRCl-like ring-finger proteins are necessary for repression of embryonic traits during vegetative growth 被引量:19
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作者 Donghong Chen Anne Molitor +1 位作者 Chunlin Liu Wen-Hui Shen 《Cell Research》 SCIE CAS CSCD 2010年第12期1332-1344,共13页
Polycomb group genes play crucial roles in the maintenance of the transcriptionally silenced state of genes for proper cell differentiation in animals and plants. While components of the polycomb repressive complex2 ... Polycomb group genes play crucial roles in the maintenance of the transcriptionally silenced state of genes for proper cell differentiation in animals and plants. While components of the polycomb repressive complex2 (PRC2) are evolutionarily conserved and their functions are extensively studied in plants, PRCI differs considerably between animals and plants, and its functions in plants are as yet not well described. Previous studies have identified the Arabidopsis AtRINGla and AtRINGlb as homologues of the animal PRC1 subunit RING1. Here, we show that the Atringla Atringlb double mutant exhibits derepression of embryonic traits during vegetative growth. Accordingly, several key regulatory genes involved in embryogenesis and stem cell activity are ectopically expressed in the mutant. Furthermore, we show that the mutant phenotypes and increased expression of regulatory genes are enhanced by the PRC2 mutant c/f. Finally, we show that three homologues of the animal PRCl-subunit ring-finger protein BMI1, AtBMIIa, AtBMIlb and AtBMIlc, can bind with AtRINGla or AtRINGIb, and in addition, AtBMIlc can bind with LHP1. The Atbmila Atbmilb double mutant shows derepression of embryonic traits similar to that of the Atringla Atringlb double mutant. Interestingly, expression levels of AtBMIla, AtBMIlb and AtBMIlc are elevated in the Atringla Atringlb mutant and those of AtBMIlc, AtRINGla and AtRINGlb are elevated in the Atbmila Atbmilb mu- tant, suggesting a self-regulatory feedback mechanism. Taken together, our results illuminate crucial functions of the PRCl-like ring-finger components in stable repression of embryonic traits and regulatory genes for proper somatic growth. 展开更多
关键词 POLYCOMB PRC 1 RING 1 somatic embrvogenesis ARABIDOPSIS
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Scientific Research in Universities of Vietnam in Present and Its Effects on Training Quality
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作者 Nguyen Huynh Phan 《Chinese Business Review》 2015年第11期539-546,共8页
In this paper, the author presented an overview of scientific research in universities of Vietnam in present and analyzed and assessed its effects on the quality of education in universities. The information to write ... In this paper, the author presented an overview of scientific research in universities of Vietnam in present and analyzed and assessed its effects on the quality of education in universities. The information to write this article was obtained in the references and from the management practice for the universities and the research institute. 展开更多
关键词 scientific research universities of Vietnam ACHIEVEMENTS weaknesses and inadequacies solution to develop scientific research
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Understanding South African mothers’challenges to adhere to exclusive breastfeeding at the workplace:A qualitative study
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作者 Nompumelelo Maponya Zelda Janse van Rensburg Alida Du Plessis-Faurie 《International Journal of Nursing Sciences》 CSCD 2021年第3期339-346,I0007,共9页
Objective:This study aimed to gain an in-depth understanding of the experience of South African working mothers in the adherence to exclusive breastfeeding when returning from maternity leave.Methods:The data of the s... Objective:This study aimed to gain an in-depth understanding of the experience of South African working mothers in the adherence to exclusive breastfeeding when returning from maternity leave.Methods:The data of the study was collected using face-to-face semi-structured interviews.Eight breastfeeding mothers were purposefully selected from two primary health care clinics in Rustenburg,North West Province,South Africa.The data were coded,categorized,and clustered into themes using Giorgi’s phenomenological analysis.Ethical considerations and measures of trustworthiness were adhered to throughout the study.Results:The findings revealed three themes:a desire for working mothers to continue the adherence to exclusive breastfeeding,workplace support for breastfeeding mothers in the adherence to exclusive breastfeeding,and an unsuitable workplace environment for the adherence to exclusive breastfeeding.Six sub-themes were identified:the need to return to the workplace soon after baby’s birth,psychological responses in the adherence to exclusive breastfeeding,lack of support from employers and coworkers in the adherence to exclusive breastfeeding,lack of or partial implementation of breastfeeding policies in the workplace,the workplace not being supportive for mothers’having to express and the workplace not being supportive for mothers’having to store breastmilk.Conclusion:Based on the findings,South African government should revisit employment policies to support working mothers who need to continue with exclusive breastfeeding after returning from maternity leave. 展开更多
关键词 Breast feeding Qualitative research South Africa WORKPLACE
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Study on Soil Properties of Eucalyptus Plantation inHainan
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作者 XU Wei ZHANG Yu-ping +3 位作者 YANG Zhen-yu LI Meng-yuan LI Si-yu YIN Li-chu 《Agricultural Science & Technology》 CAS 2019年第6期36-42,共7页
Taking Hainan Eucalyptus plantation as the research object with 4 other kinds of plantations or natural forest as reference plots, the effects of different forest land types on soil nutrient contents were analyzed, an... Taking Hainan Eucalyptus plantation as the research object with 4 other kinds of plantations or natural forest as reference plots, the effects of different forest land types on soil nutrient contents were analyzed, and the differences of soil properties were discussed. The results showed that: (1) Eucalyptus plantations were relatively helpful to reduce soil bulk density and enhance the stability of water-stable aggregates;(2) Eucalyptus plantations can improve the content of soil organic matter;(3) Soil pH showed an overall acidi fication trend under forest land conditions in Hainan;total nitrogen and alkali-hydrolyzed nitrogen content of Eucalyptus plantations showed a downward trend with the deepening of soil layer;total phosphorus and available phosphorus content showed a downward trend, while organic matter, total potassium and available K showed an upward trend. (4) The contents of total phosphorus and available phosphorus in the soil of Eucalyptus plantations of different ages did not change significantly, whereas the contents of other nutrients decreased gradually with the increase of soil depth. 展开更多
关键词 Eucalyptus plantation Soil nutrients Forest age HAINAN
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Spatiotemporal Variation of Riverine Nutrients in a Typical Hilly Watershed in Southeast China Using Multivariate Statistics Tools 被引量:2
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作者 NIE Xiao-fei LI Heng-peng +2 位作者 JIANG Jia-hu DIAO Ya-qin LI Peng-cheng 《Journal of Mountain Science》 SCIE CSCD 2015年第4期983-998,共16页
The water quality of lakes can be degraded by excessive riverine nutrients.Riverine water quality generally varies depending on region and season because of the spatiotemporal variations in natural factors and anthrop... The water quality of lakes can be degraded by excessive riverine nutrients.Riverine water quality generally varies depending on region and season because of the spatiotemporal variations in natural factors and anthropogenic activities.Monthly water quality measurements of eight water quality variables were analyzed for two years at 16 sites of the Tianmuhu watershed.The variables were examined using hierarchical cluster analysis(HCA) and factor analysis/principal component analysis(FA/PCA) to reveal the spatiotemporal variations in riverine nutrients and to identify their potential sources.HCA revealed three geographical groups and three periods.Two drainages comprising towns and large villages were the most polluted, six drainages comprising widely distributed tea plantations and orchards were moderately polluted, and eight drainages without the factors were the least polluted.The river was most polluted in June when the first heavy rain(daily rainfall > 50 mm) occurs after fertilization and the number of rainy days is most(monthly number of rainy days > 20 days).Moderate pollution was observed from October to May, during which morethan 60% of the total nitrogen fertilizer and all of the phosphorus fertilizer are applied to the cropland, the total manure is applied to tea plantations and orchards, and a monthly rainfall ranging from 0 mm to 164 mm occurs.The remaining months were characterized by frequent raining(i.e., number of rainy days per month ranged from 5 to 24) and little use of fertilizers, and were thus least polluted.FA/PCA identified that the greatest pollution sources were the runoff from tea plantations and orchards,domestic pollution and the surface runoff from towns and villages, and rural sewage, which had extremely high contributions of riverine nitrogen, phosphorus,and chemical oxygen demand, respectively.The tea plantations and orchards promoted by the agricultural comprehensive development(ACD) were not environmentally friendly.Riverine nitrogen is a major water pollution parameter in hilly watersheds affected by ACD, and this parameter would not be reduced unless its loss load through the runoff from tea plantations and orchards is effectively controlled. 展开更多
关键词 Nitrogen Phosphorus Chemical oxygen demand Spatial variation Temporal variation Water quality FERTILIZATION Tianmuhu watershed
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Comparison of the Respiratory Metabolism of Juvenile Litopenaeus vannamei Cultured in Seawater and Freshwater 被引量:1
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作者 DING Sen WANG Fang +1 位作者 DONG Shuanglin LI Ying 《Journal of Ocean University of China》 SCIE CAS 2014年第2期331-337,共7页
Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture ofL. vannamei is an important prelude to the continued development of shrimp culture ... Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture ofL. vannamei is an important prelude to the continued development of shrimp culture in China. In this study, we com- pared the respiratory metabolism of juvenile L. vannamei cultured in freshwater and saltwater by measuring their oxygen consump-tion rate (OCR), ammonium-type nitrogen excretion rate (AER) and pyruvate kinase (PK) and lactate dehydrogenase (LDH) activi-ties at different molting stages in order to physiecologically characterize juvenile L. vannamei under freshwater conditions. The re- suits showed that OCR was significantly higher in saltwater than in freshwater at all stages of molting cycle. However, variation of OCR among molting stages in saltwater was similar with that in freshwater, and the highest OCR was observed at post-molting stage. At all stages of molting cycle, AER was significantly higher in freshwater than in saltwater, and the highest was observed at post-molting stage. The activity of PK was significantly higher in saltwater than in freshwater. Conversely, the activity of LDH was higher in freshwater than in saltwater in general. Significant variation of PK and LDH activities in molting cycle was observed in saltwater and freshwater. The results indicated that aerobic metabolism of juvenile L. vannamei was more active in saltwater than in freshwater; while its protein metabolism was more active in freshwater than in saltwater. 展开更多
关键词 Litopenaeus vannamei saltwater FRESHWATER respiratory metabolism molt stage
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Simulation Nutrient Load under Climate Change Condition and Deforestation Scenarios in Phu Luong Watershed, Viet Nam
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作者 Dinh Binh Phan Thanh Hai Nguyen 《Journal of Environmental Science and Engineering(B)》 2012年第2期199-207,共9页
The purpose of this paper is to apply "Soil and Water Assessment Tool (SWAT)" model to simulate the impacts of climate change and deforestation on nutrient (nitrogen and phosphorus) yield from Phu Luong watershe... The purpose of this paper is to apply "Soil and Water Assessment Tool (SWAT)" model to simulate the impacts of climate change and deforestation on nutrient (nitrogen and phosphorus) yield from Phu Luong watershed in Northern Viet Nam. Among the three climate change scenarios B1, B2 and A2, which represented low, medium, and high levels of greenhouse gas emission respectively, were set up for Viet Nam. The B2 scenario was selected for this study. Two land use scenarios (SI-2030 and S2-2050 which converted 4.43%. and 13.40% forest-mixed land into agricultural land, respectively) were formulated by combination with climatic change in SWAT simulation. In B2 climate change scenario, mean temperature increases 0.7 ℃ (2030) and 1.3 ℃(2050); annual rainfall increases 2.1% (2030) and 3.80% (2050) with respect to baseline scenario. The results showed that monthly Nash-Sutcliffe coefficient of Efficiency (NSE) ranged from 0.81 to 0.96 and percent bias (PB1AS) ranged from -7.88 to 9.38. Additionally, SWAT simulation results also showed that climate change and deforestation caused significant percentage of changes in total N and P loads within Phu Luong watershed. 展开更多
关键词 SWAT climate change DEFORESTATION nutrient yield.
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Perception and Attitudes of Local Communities Towards Wild Elephant-related Problems and Conservation in Xishuangbanna,Southwestern China 被引量:8
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作者 HE Qingcheng WU Zhaolu +1 位作者 ZHOU Wai DONG Rui 《Chinese Geographical Science》 SCIE CSCD 2011年第5期629-636,共8页
The problem of wild elephants, or human-elephant conflict (HEC), influences the daily life of local communities and hinders the conservation of wild elephants.The perception and attitudes of local communities who inha... The problem of wild elephants, or human-elephant conflict (HEC), influences the daily life of local communities and hinders the conservation of wild elephants.The perception and attitudes of local communities who inhabited the frontiers between human activities and wild elephant movement are important to the mitigation of the HEC and conservation of wild elephants. To analyze the perception and attitudes of local communities, the Participatory Rural Appraisal (PRA) was used in the investigation of 423 interviewees from 22 villages in Xishuangbanna from July 2009 to February 2010. The results indicated that local communities had their views on the elephant-related problems. In field survey, we found that 66.5% of interviewees were willing to support, participate in, and assist in the conservation of wild elephants;33.5% of interviewees were opposed or indifferent to such conservation, because their livelihoods and even their lives were endangered by wild elephants. These views and attitudes were influenced by local communities′perception of HEC, education level, gender and self-interest. Therefore, it is necessary to analyze the diverse views among local communities and balance profits and costs in addressing HEC. 展开更多
关键词 human-elephant conflict (HEC) local community participatory rural appraisal (PRA) XISHUANGBANNA
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Micronutrient Contents of Citrus Orchard Soils in Southern China
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作者 OUYANG TAOInstitute of Soil science, Academia Sinica. P.O. Box 821, Nanjing 210008 (China) 《Pedosphere》 SCIE CAS CSCD 1993年第2期119-126,共8页
Investigations were carried out on the micronutrient contents,of major citrus orchard soils (involving seven soil great groups in 8 provinces and an autonomous region of southern China),and an evaluation on the abunda... Investigations were carried out on the micronutrient contents,of major citrus orchard soils (involving seven soil great groups in 8 provinces and an autonomous region of southern China),and an evaluation on the abundance and deficiency of available micronutrients in these soils was made in this paper.In southern China,citrus orchard soils derived from sandstone,sandy shale,Quaternary red clay,diluvial deposit,granite gneiss and neritic deposit were deficient in available Mo and B and low in Zn.Those developed on purple sandy shale,limestone and slope deposit were all in short supply of available Zn,B and Mo.Coastal solonchak was fairly abundant in B,but its available Fe,Zn and Mo contents were rather low. 展开更多
关键词 citrus orchard soil MICRONUTRIENT southern China
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Distribution of heavy metals and nutrients in rainwater in coastal regions between the southern Yellow Sea and East China Sea 被引量:1
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作者 刘昌岭 张国森 +1 位作者 任宏波 张经 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期230-237,共8页
Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values, concentrations of heavy met... Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values, concentrations of heavy metals (Cu, Pb, Zn and Cd) and nutrients (NH4+, NO3-, PO43-, SiO32-) were performed. Results indicate that concentrations of most of the heavy metals and nutrients in rainwater show clear seasonal variation, i.e. high level in winter and low level in summer. Regionally, concentrations are higher in the southern Yellow Sea than in the East China Sea, but the annual input of heavy metals into oceans by wet deposition is similar in both stations. However, the input of nutrients by wet deposition in the East China Sea is 2–3 times higher than that in the southern Yellow Sea. In individual, Pb and PO43- are input to the sea mainly by dry deposition; whereas Cu, Zn, Cd and N compounds are input dominantly by wet deposition, the N/P ratios in the rainwater from two stations are much higher than those in seawater, showing a significant impact of atmospheric wet deposition on marine production and biogeochemical circulation of nutrients in these sea regions. 展开更多
关键词 southern Yellow Sea East China Sea RAINWATER heavy metals nutrient elements
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The Feasibility Analysis of the Housing Endowment——Taking Nanjing as an example
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作者 Gao Lu 《International English Education Research》 2015年第4期36-38,共3页
China has entered the aging society, due to the imperfect national endowment insurance system, the traditional pension mode can no longer meet the needs of old people, so that the family pension and social pension are... China has entered the aging society, due to the imperfect national endowment insurance system, the traditional pension mode can no longer meet the needs of old people, so that the family pension and social pension are facing tremendous pressure. In this paper, firstly, explaining the concept of the housing endowment, and summarizing the feasibility and necessity of the housing endowment. Then through the investigation and the analysis of SPSS data, with the housing endowment in the United States and Singapore' success, summing up what our country should do to make improvements, and then we will induce the current situation and predicament of the housing endowment in Nanjing. Finally, we can put forward relevant countermeasures and suggestions by the feasibility to the reality to Nanjing city in the future. 展开更多
关键词 The housing endowment Aging population Social security.
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Evaluation of Soil Fertility Suitability of Yiliang Tobacco-growing Areas in Yunnan Province 被引量:4
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作者 Yujun WANG Jiheng ZHOU +3 位作者 Xinlang LU Lijuan CHEN Chao WANG Jiaming YANG 《Agricultural Science & Technology》 CAS 2014年第12期2150-2155,共6页
[Objective]This study was conducted to evaluate the soil fertility in Yiliantobacco-growing areas of Hunan Province.[Method]The soil nutrient contents iseven tobacco-growing towns of Yiliang County,Yunnan Province wer... [Objective]This study was conducted to evaluate the soil fertility in Yiliantobacco-growing areas of Hunan Province.[Method]The soil nutrient contents iseven tobacco-growing towns of Yiliang County,Yunnan Province were surveyefrom 2010 to 2013 and integrated soil fertility index(SFI value)was calculated tanalyze the soil fertility suitability in theses areas.[Result]The soil p H,contents oorganic matter,hydrolytic N,rapidly available K and available B were all at an appropriate level,while the contents of rapidly available P,available Mg,available Zand water-soluble Cl-were high.Among them,the contents of available P and water-soluble Cl-had great variation.Finally,the soil fertility suitability of Yiliang tobacco-growing areas was graded based on their SFI values.As a result,20%of thestobacco-growing areas were in Grade I,47.7%in Grade II,29.3%in Grade III1.5%in Grade IV and 1.5%in Grade V.The average SFI was 0.61.From 2010 t2013,the p H value and available Mg content reduced year by year,while the contents of organic matter,hydrolytic N,rapidly available P,rapidly available K,available Zn,available B and water-soluble Cl-were increased. 展开更多
关键词 Tobacco-growing soil FERTILITY Comprehensive evaluation Yiliang ofYunnan Province
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