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基于GIS改进尼勒克县滑坡灾害“发育度”模型
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作者 赵钦 赵新生 +2 位作者 杨可 赵宏伟 张晓奎 《西部探矿工程》 CAS 2011年第9期146-150,156,共6页
在全面总结分析尼勒克县滑坡灾害的分布、规模以及特征的基础上,通过基于GIS密度分析和极差变换方法为技术手段,对刘传正等提出的"四度"分层次递进分析理论中的"发育度"模型进行修改,并构建新的滑坡灾害发育度定量... 在全面总结分析尼勒克县滑坡灾害的分布、规模以及特征的基础上,通过基于GIS密度分析和极差变换方法为技术手段,对刘传正等提出的"四度"分层次递进分析理论中的"发育度"模型进行修改,并构建新的滑坡灾害发育度定量评价模型,对尼勒克县滑坡灾害发育度做定量评价。研究表明:获得的发育度定量评价结果合理、客观。 展开更多
关键词 滑坡灾害 “发育度” 分析 极差变换 GIS
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三峡库区地质灾害空间评价预警研究 被引量:70
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作者 刘传正 李铁锋 +2 位作者 温铭生 王晓朋 杨冰 《水文地质工程地质》 CAS CSCD 2004年第4期9-19,共11页
通过全面野外调查(比例尺1∶100,000),填表登录了三峡库区(19县(区),54175km2)地质灾害点5706处,其中,滑坡3830处、不稳定斜坡1107处、崩塌549处、泥石流90处、地面塌陷85处、地裂缝45处。采用1∶250,000数字化地形底图,通过编制三峡库... 通过全面野外调查(比例尺1∶100,000),填表登录了三峡库区(19县(区),54175km2)地质灾害点5706处,其中,滑坡3830处、不稳定斜坡1107处、崩塌549处、泥石流90处、地面塌陷85处、地裂缝45处。采用1∶250,000数字化地形底图,通过编制三峡库区工程地质图层,建立了基于MapGIS的三峡库区地质灾害空间数据库和分层图形库。在研究了三峡库区地质灾害分布与地形(高程、坡度)、水系、植被、工程地质岩组、地质构造形迹、斜坡类型、降雨量分布和地震活动等的统计关系基础上,筛选提取了地质灾害空间评价预警研究的发育因子(响应因子)、基础因子、诱发因子和易损因子体系。划分了三峡库区干、支流库岸的斜坡结构类型,预测建立了未来三峡水库在145~175m水位变动期水库库岸斜坡可能出现冲刷—坍塌、整体滑移、溶蚀垮塌和侵蚀—剥蚀等4种类型变形失稳模式。采用2 5km×2 5km(图面1cm×1cm)的网格剖分整个区域,共形成9309个网格。基于区域地质灾害评价预警的递进分析理论与方法(AMFP),分别计算了三峡库区地质灾害"发育度"、"潜势度"、"危险度"和"危害度"(简称"四度")。采用图斑合并方法分别编制了相应的"四度"区划图。根据"四度"区划结果,分别提出了三峡库区地质灾害监测预警与防治区划和地质环境开发利用的对策。 展开更多
关键词 三峡库区 地质灾害 MAPGIS “发育度” “潜势度” “危险度” “危害度”
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区域地质灾害评价预警的递进分析理论与方法 被引量:95
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作者 刘传正 李铁锋 +2 位作者 程凌鹏 温铭生 王晓朋 《水文地质工程地质》 CAS CSCD 2004年第4期1-8,共8页
根据多年丰富的区域地质灾害考察和综合研究实践,作者架构了区域地质灾害评价预警研究的理论体系和工作方法,主要包括:(1)开展区域地质灾害综合调查;(2)建立地质灾害信息系统,包括基于GIS的区域地质灾害空间数据库和分层图形库(GGIS);(3... 根据多年丰富的区域地质灾害考察和综合研究实践,作者架构了区域地质灾害评价预警研究的理论体系和工作方法,主要包括:(1)开展区域地质灾害综合调查;(2)建立地质灾害信息系统,包括基于GIS的区域地质灾害空间数据库和分层图形库(GGIS);(3)研究区域地质灾害分布与地形(高程、高差、坡度)、水系、植被、工程地质岩组、地质构造形迹、斜坡类型、降雨量分布和地震活动等的统计关系,为评价因子选取、分级和权重确定提供依据;(4)筛选提取评价预警研究因子体系,建立地质灾害发育因子、基础因子、诱发因子和易损因子体系;(5)创建研究区域地质灾害"发育度"、"潜势度"、"危险度"和"危害度"(简称"四度")的概念模型和数学模型;(6)在满足一定精度比例尺数字化图上划分计算单元,分别计算研究区域地质灾害"发育度"、"潜势度"、"危险度"和"危害度";(7)根据计算结果和应用目的,把相同或相近级别的图斑合并,分别编制区域地质灾害"四度"区划图;(8)根据"四度"区划结果提出研究区的地质灾害防治规划、分级监测预警目标区和地质环境可持续开发利用对策;(9)对重点地段或地点专门编制地质灾害防治预案和政府-社会联动的应急反应机制。上述9个步骤构成区域地质灾害评价预警的时空递进分析理论与方法,简称"四度"递进分析法(AM FP)。 展开更多
关键词 地质灾害 “发育度” “潜势度” “危险度” “危害度” 递进分析法(AMFP)
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Application of Comprehensive Geophysical Techniques to Predict Carbonate Fractured Reservoirs inQingxi Oilfield 被引量:1
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作者 师永民 撒利明 +3 位作者 陈广坡 田鑫 李虹 王斌婷 《Applied Geophysics》 SCIE CSCD 2005年第2期119-126,F0003,共9页
Inter-crystalline pores, cavities, and fractures created from diagenetic shrinkage of dolomite are inter-connected each other, forming fine oil- and gas-bearing reservoirs. It is hard to predict these complex fracture... Inter-crystalline pores, cavities, and fractures created from diagenetic shrinkage of dolomite are inter-connected each other, forming fine oil- and gas-bearing reservoirs. It is hard to predict these complex fracture-cavity reservoirs because of their random distribution, different growth timing, and so on. Taking the lacustrine dolomite fracture-pore reservoir in the Lower Cretaceous Xiagou Formation in the Qingxi oilfield within the Jiuquan basin as an example, we put forward a comprehensive geophysical method to predict carbonate fractures. 展开更多
关键词 Qingxi oilfield imaging logging waveform analysis tectonic stress field CARBONATE and fracture prediction
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TEMPERATURE DEPENDENT DEVELOPMENT OF ASIAN CORN BORER Ostrinia furnacalis 被引量:7
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作者 李正跃 《Zoological Research》 CAS CSCD 1998年第5期389-396,共8页
Temperature dependent development in the Asian corn borer, Ostrinia furnacalis (Guenee) was determined at nine constant temperatures between 10℃ and 34℃. Except for 10℃ development of all life stages occurred a... Temperature dependent development in the Asian corn borer, Ostrinia furnacalis (Guenee) was determined at nine constant temperatures between 10℃ and 34℃. Except for 10℃ development of all life stages occurred at the temperatures tested, however, mortality was significantly great at the extreme temperatures(12℃ and 34℃). Egg, larvae and pupae duration accounted for 17%, 57% and 25% of total one of immature stage, respectively Lower developmental thresholds estimated to be 10 38, 10 06 and 11 07℃ for eggs, larvae and pupae, respectively. Upper limited thresholds were 28 00, 31 00 and 31 00℃ for eggs, larvae and pupae, respectively. The heat unit requirements for egg stage were 79 15 degree days, for larval stage were 339 73 degree days, and for pupal stage were 128 82 degree days, respectively. Overall, heat unit requirements for development from egg to adult were 539 91 degree days between lower developmental threshold 10 35℃ and upper limited threshold 32℃. 展开更多
关键词 Asian corn borer Temperature development Thresholds Degree days
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Effects of Light Intensity on Growth, Development and Formation on Fagopyrum cymosum 被引量:1
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作者 华劲松 戴红燕 《Agricultural Science & Technology》 CAS 2014年第3期363-366,共4页
Effects of light intensity on growth, development and formation on Fagopy- rum cymosum were explored with natural light intensities at 100%(A), 85.2%(B), 75.8%(C) and 59.7%(D). The results showed that the decl... Effects of light intensity on growth, development and formation on Fagopy- rum cymosum were explored with natural light intensities at 100%(A), 85.2%(B), 75.8%(C) and 59.7%(D). The results showed that the decline of light intensity re- duced nutrient growth period, so that plant growth stage entered in advance and extended, which indicated that the decline of light intensity would lower leaf number and area, the number of twigs from the stem, as well as photosynthate. Further- more, the reduction degree increased upon light intensity decrease degree, and the proper shading improved stem height and leaf area enhanced before growth term. 展开更多
关键词 Fagopyrum cymosum Light intensity Growth and development Morpho- logical characters
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Study on the Datong Yak's Skin Development
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作者 张勤文 俞红贤 +3 位作者 荆海霞 魏青 薛乾 梁林 《Agricultural Science & Technology》 CAS 2010年第9期118-120,125,共4页
[Objective] This study was to explore the skin development law of Datong Yak.[Method]Taking Datong yaks at four various growth stages(1 day old,30 days old,180 days old and adult)as experimental materials,we studied... [Objective] This study was to explore the skin development law of Datong Yak.[Method]Taking Datong yaks at four various growth stages(1 day old,30 days old,180 days old and adult)as experimental materials,we studied histological structure of Datong yak skin by employing the histological methods.[Results]The skins of Datong yak at four various growth stages all showed the characteristics of thinner epidermis and thicker hypodermis,and of less capillary vessels in hypodermis and more pigment cells in epidermis.Datong yak at four various growth stages all showed a fluctuating trend in entire skin thickness,in detail thickening from 1 day old to 30 days old,then thinning to 180 days old,again thickening to adult.[Conclusion]The results provided theoretical basis for further understanding the structural characteristics of Datong yak to adapt to the abominable plateau environment. 展开更多
关键词 YAK Skin thickness Development law
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A Molecular Phylogeny of Macaca Based on Mitochondrial Control Region Sequences 被引量:8
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作者 李青青 张亚平 《Zoological Research》 CAS CSCD 北大核心 2004年第5期385-390,共6页
Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity ... Nucleotide sequences of segments of the mitochondrial control regions were analyzed to infer the phylogenetic relationships among 7 macaques.High nucleotide diversity in Macaca assamensis and relatively low diversity in M.thibetana were found.Based on the ML tree from control regions,species in our study can roughly be sorted into three species groups except for the phylogenetic position of M.fascicularis,i.e.,silenus group,including M.leonina;sinica group,including M.arctoides,M.assamensis,and M.thibetana;and fascicularis group,including M.mulatta and M.cyclopis.A discrepancy between earlier studies (Fooden & Lanyon,1989;Tosi et al,2003a;Deinard & Smith,2001;Evans et al,1999;Hayasaka et al,1996;Morales & Melnick,1998),our result supported the hypothesis that M.fascicularis diverged earlier than M.leonina.Mitochondrial paraphyly in eastern M.mulatta (with respect to M.cyclopis) and eastern M.assamensis (with respect to M.thibetana) were clearly observed in our study.In accordance with the results of Y chromosome,allozyme,nuclear genes and some morphological data (Delson,1980;Fooden & Lanyon,1989;Fooden,1990;Tosi et al,2000,2003a,b;Deinard & Smith,2001),our study on control region sequences supported M.arctoides to be classified into the sinica group.However,this result disagreed with the previous mtDNA studies (Hayasaka et al,1996;Morales & Melnick,1998;Tosi et al,2003a). 展开更多
关键词 MACACA MACAQUE Mitochondrial DNA Control region PHYLOGENY
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Effects of Combined Pollution of Pb and Cd on Growth and Yield of Rice 被引量:14
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作者 王永强 肖立中 +2 位作者 李诗殷 郭杨 蔡信德 《Agricultural Science & Technology》 CAS 2010年第5期168-170,共3页
[Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice. [Method]Effects of combined pollution of Pb and Cd on the growth and yield of ... [Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice. [Method]Effects of combined pollution of Pb and Cd on the growth and yield of rice were studied by pot experiment with cultivating rice. [Result] Pb and Cd could promote rice growth at low concentration while inhibit plant height at high concentration; Pb and Cd stress reduced the number of rice tillers significantly,with the increasing of stress concentration,the decrease amplitude of the number of tillers was greater; the panicle per pot,seed setting rate,1 000-grain weight and yield of rice were reduced significantly by Pb and Cd stress,the grain number per panicle decreased significantly under low concentration of Pb and Cd but increased significantly under high concentration; the brown rice rate and milled rice rate increased significantly under low concentration of Pb and Cd while at high concentration of Pb and Cd,the both two reduced significantly,the head milled rice rate reduced significantly with the decreasing of concentration; The Pb and Cd content of grains were significantly positively related to the concentrations of Pb and Cd content in soil,it had excessively exceeded hygienic standard when the concentrations of Pb and Cd in soil were medium-high and the unqualified rate reached 333% and 122%. [Conclusion]The study had provided basis for the establishment of rice cultivation system in pollution areas. 展开更多
关键词 Combined pollution of Pb and Cd Soil Rile (Oryza stiva/L.) Growth Yield
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Effects of temperature and salinity on the development of embryos and larvae of the veined rapa whelk Rapana venosa(Valenciennes, 1846) 被引量:4
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作者 班绍君 张涛 +3 位作者 潘恒倩 潘洋 王平川 薛东秀 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期773-782,共10页
The major population of the veined rapa whelk Rapana venosa (Valenciennes, 1846), which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature (16-34... The major population of the veined rapa whelk Rapana venosa (Valenciennes, 1846), which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature (16-34℃ at salinity 30) and salinity (5-45 at 25℃) on the incubation period and subsequent larval development. In the temperature experiment, the shortest incubation period was 12 days at 34℃, the lower temperature limit was 16~C, the longest mean shell length (1 193+17 pan) occurred at 25℃ and the highest survival rate 72.28%+5.62% was observed at 28℃. In the salinity experiment, the shortest incubation period was 15 days at 25. The salinity tolerance range was 15-40, the longest mean shell length (855-4-9 μm) and the highest survival rate 72.93%~4.85% were both observed at 35. This study demonstrated that, during the egg-mass stage, temperature and salinity regimes influence later growth and survival of larvae. These observations deepen our understanding of the ecology and conservation of natural populations of Rapana venosa. 展开更多
关键词 Rapana venosa EMBRYO LARVAE TEMPERATURE SALINITY
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Relationship of Resistivity with Water Content and Fissures of Unsaturated Expansive Soils 被引量:7
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作者 CHEN Liang YIN Zong-ze ZHANG Pei 《Journal of China University of Mining and Technology》 EI 2007年第4期537-540,共4页
The development of fissures in expansive soils has a great effect on the stability of slope. Of the three phases of soils,the gas phase and solid phase are relatively insulated,so the average resistivity of soils can ... The development of fissures in expansive soils has a great effect on the stability of slope. Of the three phases of soils,the gas phase and solid phase are relatively insulated,so the average resistivity of soils can be calculated from the resistivity of the liquid phase. On this basis,the two-part model of resistivity changing with the water saturation of the expansive soil can be deduced. A 2-D resistance grid model is established based on simulating the resistance of ver-tically developed fissures. Variation in measured resistance of vertically developed fissures at different positions can be calculated from this model. Fissure development can be inversely determined from the variation in the measured resis-tance. Finally,the model is verified by an indoor resistivity test for remolded soil samples,indicating that the test result agrees well with that of the model established. 展开更多
关键词 unsaturated expansive soil RESISTIVITY fissure development degree of saturation resistivity structural model
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Effects of Salinity on Embryonic Development, Survival, and Growth of Crassostrea hongkongensis 被引量:9
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作者 HUO Zhongming WANG Zhaoping +5 位作者 LIANG Jian ZHANG Yuehuan SHEN Jianping YAO Tuo SU Jiaqi YU Ruihai 《Journal of Ocean University of China》 SCIE CAS 2014年第4期666-670,共5页
This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artific... This study examined the effects of salinity on embryonic development, survival, and growth of the Hong Kong oyster Crassostrea hongkongensis. The embryos, larvae, and juveniles of C. hongkongensis were held in artificial seawater at three different salinities(low, 15; medium, 23; and high, 30) to determine the optimum hatchery and nursery conditions for mass production of the seeds. Results showed that the percentage production of straight-hinged larvae from fertilized eggs was significantly lower at the high salinity than at the low- and medium-salinities(P < 0.05). The survival rates of larvae and juveniles differed significantly among the three salinity trials, with the highest survival rate observed at the low salinity(P < 0.05). The shell height of larvae was significantly larger at the low salinity than at the high and medium salinities from days 9 to 15(P < 0.05), whereas that of juveniles was significantly larger at the low salinity than at the high and medium salinities on day 70(P < 0.05). These results indicate that the larvae and juveniles of C. hongkongensis are tolerant to a wide range of salinities(15 to 30), but show better growth and survival at relatively low salinities. Thus, it is recommended to use relatively low salinities in hatchery and nursery systems for improved yields of C. hongkongensis. 展开更多
关键词 SALINITY embryonic development SURVIVAL GROWTH Crassostrea hongkongensis
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Development characteristics and quantitative prediction of reservoir fractures in the Chaoyanggou oil field 被引量:3
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作者 ZHANG Zhen TONG Heng-mao BAO Zhi-dong 《Mining Science and Technology》 EI CAS 2009年第3期373-379,共7页
The Chaoyanggou oil field is a fractured low-permeability reservoir, where the distribution of oil and gas is controlled by the distribution and development of fractures.Based on outcrop, drilling core, thin section a... The Chaoyanggou oil field is a fractured low-permeability reservoir, where the distribution of oil and gas is controlled by the distribution and development of fractures.Based on outcrop, drilling core, thin section and log data, the development characteristics of fractures in this area are described.On this basis, the degree of fracture development was predicted by quantitative analysis of fracture strength and numerical simulation.The result shows that four groups of structural fractures, i.e., in near NS, and EW directions and in due NW and NE directions, were developed in the reservoir, with the nearly NS and EW fractures dominant, which are the along bedding decollement fractures formed by compressive folding action, while low angle shear fractures are related to thrusts.These fractures are mainly formed in the reversed tectonic stage at the end of the Mingshui formation during the Cretaceous period.The degree of fracture development is controlled by such factors as lithology, stratum thickness, faults, folds and depth.The fractures are developed with a clear zonation and are best developed in the northern zone, moderately developed towards the south and poorly developed in the middle zone.These prediction results are in good agreement with interpretation results from logs. 展开更多
关键词 FRACTURE development characteristic fracture strength numerical simulation Chaoyanggou oil field
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Molecular cloning and function analysis of insulin-like growth factorbinding protein 1a in blunt snout bream(Megalobrama amblycephala) 被引量:1
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作者 Yu-Mei TIAN Jie CHEN +2 位作者 Yang TAO Xia-Yun JIANG Shu-Ming ZOU 《Zoological Research》 CAS CSCD 北大核心 2014年第4期300-306,共7页
Insulin-like growth factor-binding protein 1 (IGFBP-1), a hypoxia-induced protein, is a member of the IGFBP family that regulates vertebrate growth and development. In this study, full-length IGFBP-la cDNA was clone... Insulin-like growth factor-binding protein 1 (IGFBP-1), a hypoxia-induced protein, is a member of the IGFBP family that regulates vertebrate growth and development. In this study, full-length IGFBP-la cDNA was cloned from a hypoxia-sensitive Cyprinidae fish species, the blunt snout bream (Megalobrama arnblycephala). IGFBP-la was expressed in various organs of adult blunt snout bream, including strongly in the liver and weakly in the gonads. Under hypoxia, IGFBP-la mRNA levels increased sharply in the skin, liver, kidney, spleen, intestine and heart tissues of juvenile blunt snout bream, but recovered to normal levels after 24-hour exposure to normal dissolved oxygen. In blunt snout bream embryos, IGFBP-la mRNA was expressed at very low levels at both four and eight hours post-fertilization, and strongly at later stages. Embryonic growth and development rates decreased significantly in embryos injected with IGFBP-la mRNA. The average body length of IGFBP-la-overexpressed embryos was 82.4% of that of the control group, and somite numbers decreased to 85.2%. These findings suggest that hypoxia-induced IGFBP-la may inhibit growth in this species under hypoxic conditions. 展开更多
关键词 Megalobrama amblycephala IGFBP-la HYPOXIA OVEREXPRESSION
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The characteristics of rill development and their effects on runoff and sediment yield under different slope gradients 被引量:11
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作者 HE Ji-jun SUN Li-ying +2 位作者 GONG Hui-li CAI Qiang-guo JIA Li-juan 《Journal of Mountain Science》 SCIE CSCD 2016年第3期397-404,共8页
Rill formation is the predominant erosion process in slope land in the Loess Plateau, China. This study was conducted to investigate rill erosion characteristics and their effects on runoff and sediment yielding proce... Rill formation is the predominant erosion process in slope land in the Loess Plateau, China. This study was conducted to investigate rill erosion characteristics and their effects on runoff and sediment yielding processes under different slope gradients at a rate of 10°, 15°, 20° and 25° with rainfall intensity of 1.5 mm min-1 in a laboratory setting. Results revealed that mean rill depth and rill density has a positive interrelation to the slope gradient. To the contrary, width-depth ratio and distance of the longest rill to the top of the slope negatively related to slope gradient. All these suggested that increasing slope steepness could enhance rill headward erosion, vertical erosion and the fragmentation of the slope surface. Furthermore,total erosion tended to approach a stable maximum value with increasing slope, which implied that there is probably a threshold slope gradient where soil erosion begins to weaken. At the same time, the correlation analysis showed that there was a close connection between slope gradient and the variousindices of soil erosion: the correlation coefficients of slope gradient with maximal rill depth, number of rills and the distance of the longest rill from the top of the slope were 0.98, 0.97 and-0.98, respectively,indicating that slope gradient is the major factor of affecting the development of rills. Furthermore,runoff was not sensitive to slope gradient and rill formation in this study. Sediment concentration,however, is positively related to slope gradient and rill formation, the sediment concentrations increased rapidly after rill initiation, especially. These results may be essential for soil loss prediction. 展开更多
关键词 Rill erosion Erosion processes Simulated rainfall Runoff Slope gradient
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Effects of light intensity on activity in four sympatric anuran tadpoles 被引量:1
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作者 Guo-Hua DING Zhi-Hua LIN +2 位作者 Li-Hua ZHAO Xiao-Li FAN Li WEI 《Zoological Research》 CAS CSCD 北大核心 2014年第4期332-337,共6页
Though light conditions are known to affect the development and anti-predation strategies of several aquatic species, relatively little is known about how different species react to light, or how light can affect thes... Though light conditions are known to affect the development and anti-predation strategies of several aquatic species, relatively little is known about how different species react to light, or how light can affect these species during different points in their life-cycle. In this study, we used four sympatric anuran tadpoles (Bufo gargarizans, B. melanostictus, Pelophylax nigromaculatus and Microhyla fissipes) as animal system to examine species-specific activities of the underdoing different light intensity treatments, so as to better understand how they respond to light. We exposed four different species of tadpoles to 1660 and 14 lux light intensity treatments and then measured several parameters including development stage, body length and tail length, and as well as their basic activities. The results of this observation and analysis showed that the activities of tadpoles were significantly greater in B. gargarizans and B. melanostictus than in P. nigromaculatus and M. fissipes; and were also significantly greater during times of high light intensity as compared to during low light intensity. Moreover, the observed relationship between species and light intensity was significant. The activities ofB. gargarizans and B. melanostictus tadpoles were greater in high light, while the activity of P. nigromaculatus tadpoles was greater in low light intensity, while M. fissipes tadpoles showed no differences in either low or high intensity light. Furthermore, the activities orB. gargarizans, B. melanostictus and M. fissipes tadpoles in terms of developmental stage, body size or tail length did not seem to differ with light intensity, but during early larval developmental period of P. nigromaculatus, the activity of tadpoles was negatively correlated with development stage, but irrelevant to either body size or tail length in different light intensities. These results lead us to conclude the observed activities of the four sympatric anuran tadpoles are closely correlated with their specific anti-predation strategies. 展开更多
关键词 ANURA ACTIVITY Developmental stage Light intensity TADPOLE
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The effects of temperature and substrate on ontogenetic behavior of bastard halibut, Paralichthys olivaceus (T. et S.)
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作者 刘栋 线薇薇 朱鑫华 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第1期65-71,共7页
The effects of temperature and substrate on ontogenetic patterns and settlement behavior of bastard halibut, Paralichthys olivaceus (T. et S.) were studied in a series of laboratory experiments. Analysis on stage-base... The effects of temperature and substrate on ontogenetic patterns and settlement behavior of bastard halibut, Paralichthys olivaceus (T. et S.) were studied in a series of laboratory experiments. Analysis on stage-based data revealed that except for settlement, and compared to the substrate, the ambient temperature dominantly controlled the hatch success and subsequent development of the species. The oosperm optimum survival rate of 60% during hatching occurred at 20℃, and survival rate of 29%, at 18℃ for larval rearing. The survival rate of larvae reared under variable temperature of 3.5–4.5℃ was higher than that of those reared under stable temperature. The maximum survival rate of 29%, corresponded to variation at temperature of 4℃. With increase in age newly settled juveniles preferred to lie on the fine substrate and gradually moved on the coarse substrate. GLM (general linear model) analysis showed that the combination of temperature and substrate had no significant impact on the survival of settling larvae, but definitely affected the duration of settlement. 展开更多
关键词 TEMPERATURE SUBSTRATE survival rate settlement metamorphosis Paralichthys olivaceus (T et. S)
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Viticultural Performance of Merlot and Cabernet Sauvignon (Vitis vinifera L.) Cultivated in High Altitude Regions of Southern Brazil
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作者 Jaqueline Nogueira Muniz Suzeli Simon +6 位作者 Alberto Fontanella Brighenti Luciane Isabel Malinovski Carolina Pretto Panceri Gabriella Vanderlinde Juliana Welter Debora Dal Zotto Aparecido Lima da Silva 《Journal of Life Sciences》 2015年第9期399-410,共12页
Different studies show that the altitude regions of the State of Santa Catarina have great potential for the production of grapevine varieties. The aim of this study was to characterize the phenological development, d... Different studies show that the altitude regions of the State of Santa Catarina have great potential for the production of grapevine varieties. The aim of this study was to characterize the phenological development, determine the thermal requirements in degree-days (DD), the index heliothermic (IH) and climatic variables during the vegetative and productive development of varieties Merlot and Cabernet Sauvignon grown in Campo Belo do Sul (27°40′04″ S, 50°44′48″ W, altitude 950 m a.s.l.) and Sao Joaquim (28°15′13″ S, 49°57′02″ W, altitude 1,400 m a.s.l.) during 2012/2013 cycle. Phenological stages evaluated were bud break, full bloom, veraison and maturity. Higher temperatures, global radiation, PAR and lower volumes of rainfall were the main climatic parameters that differentiated Campo Belo do Sul from Sao Joaquim. Due to occurrence of higher temperatures, Campo Belo do Sul presented thermal summation around 40% higher than Sao Joaquim. The low temperatures of Sao Joaquim extended the period of grape ripening and were responsible for the highest levels of titratable acidity and the higher concentrations of anthocyanins and total polyphenols in both varieties. The results show that in the altitude ranges studied (900 and 1400 m), climatic behavior and viticultural performance of Cabernet Sauvignon and Merlot were suitable for producing quality wines. 展开更多
关键词 Climate PHENOLOGY technological maturation total polyphenols.
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Morphogenesis of Oil Palm Fruit (Elaeis guineensis Jacq.) in Mesocarp and Endocarp Development 被引量:1
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作者 Hermine Bille Ngalle Joseph Martin Bell +3 位作者 Georges Franck Ngando Ebongue Lambert Nyobe Felix Chancelin Ngangnou Godswill Ntsefong Ntsomboh 《Journal of Life Sciences》 2013年第2期153-158,共6页
This work aims to study the development of the pericarp of the fruit of Elaeis guineensis Jacq. var. dura. The thickness, the water and the oil contents of its tissues are evaluated every two weeks, from pollination t... This work aims to study the development of the pericarp of the fruit of Elaeis guineensis Jacq. var. dura. The thickness, the water and the oil contents of its tissues are evaluated every two weeks, from pollination to the maturity of the fruit. The development of the oil palm fruit takes 5.5 months. The endocarp reaches its maximum thickness at the 70th DPP (day post-pollination), with a water content of 72%. It then starts its dehydration, while sclerifying. It therefore isolates the seed at start and later protects it. The mesocarp is visible at anthesis and its water content is close to 92%. From the 100th DPP, it begins a continuous dehydration associated, from the 130th DPP, with an active lipids biosynthesis. Ultimately, the pericarp of the oil palm fruit fulfills both functions, namely to protect the seed by early sclerification of the endocarp and ensure the dissemination of the species by the high oil content of the mesocarp. A comparative anatomy of the pericarp tissues of the three genotypes.of E. guineensis Jacq., during the first three weeks of fruit development, will enhance the understanding of the primary effect of sh gene. 展开更多
关键词 Elaeis guineensis Jacq. FRUIT ENDOCARP MESOCARP development.
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Survey of cyanomyovirus abundance in Shantou coastal waters by g20 被引量:1
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作者 李传标 丁俊 +4 位作者 周立镇 张昭 李升康 刘文华 温小波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第3期604-615,共12页
To understand the genetic diversity and population changes in cyanophages in the coastal waters of Shantou, northeast South China Sea, we used the capsid assembly protein gene g20 as a marker of the abundance and phyl... To understand the genetic diversity and population changes in cyanophages in the coastal waters of Shantou, northeast South China Sea, we used the capsid assembly protein gene g20 as a marker of the abundance and phylogeny of natural cyanomyovirus communities. The abundance of total viruses, heterotrophic bacteria, and picophytoplankton in the coastal waters was monitored with flow cytometry. Hydrological parameters (NO3^-, NO2^-, NH3, soluble reactive phosphorus, total dissolved nitrogen, total dissolved phosphorus, dissolved oxygen, chemical oxygen demand, temperature, salinity, and chlorophyll a concentration) and microbial abundance (total viruses, total bacteria, Prochlorococcus, Synechococcus, and eukaryotes) were measured in the upper and lower layers at four sampling sites in the research area. In the direct viral counts, cyanomyoviruses accounted for 1.92% to 〉10% of the total viral community. A phylogenetic analysis showed that the g20 sequences in the Shantou coastal waters were very diverse, distributed in eight distinct operational taxonomic units, including the newly formed Cluster W. The g20 gene copies inferred from real time PCR assay indicated that cyanomyovimses were correlated significantly with the heterotrophic bacteria numbers and the nitrate and chlorophyll a concentrations. These results suggest that cyanomyoviruses are ubiquitous and are an abundant component of the virioplankton in Shantou coastal waters. 展开更多
关键词 cyanomyovims G20 Shantou coastal water
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