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Application of Community Climate Change Adaptation Assessment Tools for Climate Adaptation Planning in Yala Wetlands Complex, Lake Victoria Basin, Kenya
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作者 Maurice Ogoma Leonard Akwany Roniance Adhiambo 《Open Journal of Ecology》 2023年第5期271-290,共20页
Yala Wetland is a complex of Nzoia and Yala rivers that drain their waters into Lake Victoria, but face various pressure which is thought to originate from the impacts of climate change. The riparian communities are g... Yala Wetland is a complex of Nzoia and Yala rivers that drain their waters into Lake Victoria, but face various pressure which is thought to originate from the impacts of climate change. The riparian communities are generally poor and use the wetland resources for small-holder livelihood activities. This paper describes how community climate change adaptation assessment (C3A2) tools were applied to identify resilient community-level adaptation options and would inform local climate adaptation planning. Eight participatory C3A2 tools were applied for data collection in which two (adaptation attributes and story-telling) were administered at the meso or local government (County) level while all the eight tools (community protocol, risk mapping, techno-transect, resilience ranking, community calendars, story-telling, adaptation attributes and give back) were administered at the micro or community level. Qualitative research method was adopted and 80 respondents (20 at meso and 60 at micro) were purposively selected for the study. Data were collected through interviews, focus group discussions (FGD), and plenary discussions. Data were analyzed at four levels: pre-analysis in situ, daily team triangulation, team conclusions, and cross-community reporting. The study found that communities experienced climate risks that tended to shift along with prolonged and irregular hydro-meteorological events, which affected their capacities for adaptation especially the resource-constrained individuals and vulnerable households. Drought (45%) and flood hazards (39%) were the most felt strongly. Drought was manifested mainly by prolonged dry-spell, increased atmospheric temperatures, and strong winds while floods were characterized by unpredictable and short but high-intensity rainfall with associated loss of lives and property damage. Women, children, and poor households were the most exposed to climatic hazards. Farm/agro-forestry was the most perceived adaptation strategy for drought, flood, and soil erosion while alternative livelihoods particularly ecotourism was the commonly perceived adaptation strategy for human-wildlife conflict (HWC). Three community-based adaptation action plans (CBAP) were prepared to guide future village-level planning and development. The CBAPs were used to identify three sample projects which were funded by the donor and implemented by the community. The C3A2 approach provides adequate participatory tools that can be applied in the lake and river basins, and potentially other ecosystems to guide the development of community-based adaptation plans and resilient community-based adaptation projects with wider local acceptance especially those geared towards designing programs for climate-smart livelihoods. However, the application of the methodology may be site-specific and the tools can be administered based on local scenarios and the availability of resources. 展开更多
关键词 Climate Change ADAPTATION Climate-Smart Yala Wetlands Lake victoria Livelihoods
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2006~2007年深圳市Victoria系B型流感病毒HA1基因特性的分析 被引量:4
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作者 周丽 吕星 +1 位作者 程小雯 房师松 《中国卫生检验杂志》 CAS 2008年第5期847-848,925,共3页
目的:了解2006-2007年深圳市Victoria系B型流感病毒流行情况及HA1基因特性。方法:用狗肾传代细胞(MDCK)和鸡胚进行流感病毒分离,将分离到的Victoria系B型流感毒株进行血凝素HA片段核苷酸序列测定并推导出其氨基酸序列,用SIMMONIC软... 目的:了解2006-2007年深圳市Victoria系B型流感病毒流行情况及HA1基因特性。方法:用狗肾传代细胞(MDCK)和鸡胚进行流感病毒分离,将分离到的Victoria系B型流感毒株进行血凝素HA片段核苷酸序列测定并推导出其氨基酸序列,用SIMMONIC软件和Mega软件对其进行分析。结果:2006-2007年深圳分离培养到的Victoria系流感毒株与同时段的疫苗株B/Malaysia/2506/04、国内代表株B/Shenzhen/155/05的核苷酸同源性极高,没有发生较大的变异;2006-2007年深圳所有的Victoria系株均在134号位点上发生了Ser到Pro的替换。除此之外,还存在个别的氨基酸点变异,部分的变异位点处在HA1区的抗原表位,会导致病毒的抗原性改变。结论:本研究未发现2007年深圳流行的Vic-toria系B型流感毒株与2006年的流行株在HA1片段有明显的氨基酸变异。 展开更多
关键词 victoria B型流感 HA1基因特性 糖基化位点
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商标淡化理论的新转折——评美国Victoria's Secret案 被引量:8
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作者 马宁 杨晖 《电子知识产权》 CSSCI 2004年第2期42-44,共3页
2003年3月,美国联邦最高法院对一则经过两审的商标淡化争议案件-Moseley V.Secret Cara-logue,Inc.(简称Victoria′Secret)一案作出终审判决,从而结束了围绕联邦商标反淡化法(FTDA)实施以来司法实践中见解不一的局面,使商标淡化理论发... 2003年3月,美国联邦最高法院对一则经过两审的商标淡化争议案件-Moseley V.Secret Cara-logue,Inc.(简称Victoria′Secret)一案作出终审判决,从而结束了围绕联邦商标反淡化法(FTDA)实施以来司法实践中见解不一的局面,使商标淡化理论发生了新的转折.该案的判决对我们全面理解、运用商标淡化理论提供了借鉴,并将对我国在美企业的商标策略产生一定的影响. 展开更多
关键词 商标淡化理论 美国 商标策略 victoria’s Secret案 立法 驰名商标 司法工作 贸易投资
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王莲属(Victoria)植物分类学地位的确立 被引量:1
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作者 李淑娟 尉倩 +2 位作者 尚煜东 刘安成 吴永朋 《自然杂志》 2017年第4期293-298,共6页
王莲是世界著名的热带水生观赏植物,有"水生花王"之称,深受人们的喜爱。在相关文献记载中,其发现人和植物学命名人说法各异,拉丁名混乱不一,影响对王莲的进一步研究。通过查阅原始资料,考证了王莲属分类学地位的确立及物种命... 王莲是世界著名的热带水生观赏植物,有"水生花王"之称,深受人们的喜爱。在相关文献记载中,其发现人和植物学命名人说法各异,拉丁名混乱不一,影响对王莲的进一步研究。通过查阅原始资料,考证了王莲属分类学地位的确立及物种命名的历史,探究了种名出现错误的原因。结果表明,王莲的属名是以维多利亚女王的名字Victoria来命名的,由John Lindley先生在1837年确立,该属有两个种,亚马逊王莲和克鲁兹王莲。亚马逊王莲的发现与命名一直颇受争议,目前,被广泛接受的种名是Victoria amazonica(Poepp.)J.C.Sowerby,该学名由皇家植物学会的秘书长James De Carle Sowerby先生于1850年确定;克鲁兹王莲的种名是Victoria cruziana A.D’Orbigny,由Alcide D'Orbigny先生1840年命名。 展开更多
关键词 王莲属(victoria) 发现 命名史
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北太平洋海温Victoria模态与ENSO年际关系的非对称特征 被引量:1
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作者 祁莉 毛欣 张文君 《大气科学学报》 CSCD 北大核心 2022年第2期280-291,共12页
利用美国NOAA海表温度资料,重点分析了北太平洋海温异常EOF第二模态Victoria模态(VM)与ENSO年际关系的非对称特征。研究发现,VM和ENSO在年代际尺度上相关性较弱,而在年际尺度上有很好的相关关系,两者同期为负相关,VM超前1 a为正相关。然... 利用美国NOAA海表温度资料,重点分析了北太平洋海温异常EOF第二模态Victoria模态(VM)与ENSO年际关系的非对称特征。研究发现,VM和ENSO在年代际尺度上相关性较弱,而在年际尺度上有很好的相关关系,两者同期为负相关,VM超前1 a为正相关。然而,正负VM事件与ENSO冷暖位相在年际尺度上的联系存在着一定的非对称性。正VM事件与同年冬季热带中东太平洋海温异常的联系较弱,但次年常有厄尔尼诺事件发生;相比较而言,负VM事件在同年一般都有厄尔尼诺事件伴随发生,而与次年冬季热带中东太平洋海温没有显著联系,且很少有ENSO事件发生。由此可见,正VM事件对次年厄尔尼诺的发生发展似乎有促进作用,可作为ENSO前期预报因子之一,而负VM事件不能作为ENSO的前期预报因子。 展开更多
关键词 北太平洋海温 victoria模态 ENSO 非对称性
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王莲(Victoria)杂交后代表型观察分析 被引量:2
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作者 李淑娟 尉倩 +2 位作者 尚煜东 吴永朋 刘安成 《植物遗传资源学报》 CAS CSCD 北大核心 2017年第5期974-983,共10页
以克鲁兹王莲ב朗伍德王莲自交后代’的58个后代为材料,观察分析了叶片卷边颜色、花蕾形状、萼片颜色、萼片着刺数、第1晚和第2晚花色等10个主要性状的分离情况,并对个体性状分离类型进行了聚类。结果表明,其后代性状分离极为广泛... 以克鲁兹王莲ב朗伍德王莲自交后代’的58个后代为材料,观察分析了叶片卷边颜色、花蕾形状、萼片颜色、萼片着刺数、第1晚和第2晚花色等10个主要性状的分离情况,并对个体性状分离类型进行了聚类。结果表明,其后代性状分离极为广泛,主要表现为负向中亲优势、正向中亲优势和超亲优势。第1晚内瓣色、拟雄蕊尖色、第2晚内瓣色、第2晚外瓣色及第2晚内外瓣色差5个性状之间有高度或显著相关性,其余相关性较低;卷边色、蕾形、萼片颜色、着刺数及第1晚外瓣色5个性状独立遗传的可能性大。个体性状分离类型丰富,主要可分为7大类,绿叶粉花白芯型、红叶玫红花白芯型、绿叶玫红花深玫红芯型、红叶玫红花深玫红芯型、绿叶深玫红花白芯型、红叶粉花深玫红芯型、绿叶萼多刺玫红花白芯型。 展开更多
关键词 王莲 杂交 后代 性状分离
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Constraints on early Paleozoic magmatic processes and tectonic setting of Inexpressible Island, Northern Victoria Land, Antarctica 被引量:2
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作者 CHEN Hong WANG Wei ZHAO Yue 《Advances in Polar Science》 CSCD 2019年第1期52-69,共18页
During the Cambrian and Ordovician, widespread magmatic activity occurred in the Ross Orogen of central Antarctica, forming the Granite Harbor Intrusives and Terra Nova Intrusive Complex. In the Terra Nova Intrusive C... During the Cambrian and Ordovician, widespread magmatic activity occurred in the Ross Orogen of central Antarctica, forming the Granite Harbor Intrusives and Terra Nova Intrusive Complex. In the Terra Nova Intrusive Complex, the latest magmatic activity comprised the emplacement of the Abbott Unit(508 Ma) and the Vegetation Unit(~475 Ma), which were formed in different tectonic settings. Owing to their similar lithological features, the tectonic transformation that occurred between the formation of these two units has not been well studied. Through a detailed geological field investigation and geochemical and geochronological analyses, four types of magmatic rock—basalt, syenite, mafic veins, and granite veins—were identified on Inexpressible Island, Northern Victoria Land. Our SHRIMP(Sensitive High Resolution Ion Micro Probe) zircon U–Pb ages of the basalt and the granite veins are 504.7 ± 3.1 and 495.5 ± 4.9 Ma, respectively. Major-and trace-element data indicate a continental-margin island-arc setting for the formation of these two rock types. The zircon U–Pb ages of the syenite and the monzodiorite veins are 485.8 ± 5.7 and 478.5 ± 4.0 Ma, respectively. Major-and trace-element compositions suggest a collisional setting for the former and an intracontinental extensional setting for the latter. These results elucidate the evolution from subduction to collision and intracontinental extension in Northern Victoria Land during the 20 Ma spanning the late Cambrian–Early Ordovician and improve our understanding of the tectonics and evolution of the Ross Orogen in the Transantarctic Mountains. 展开更多
关键词 Northern victoria Land Ross OROGEN Early PALEOZOIC MAGMATISM ISLAND-ARC intracontinental extension
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No evidence for a genetic association between female mating preference and male secondary sexual trait in a Lake Victoria cichlid fish 被引量:3
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作者 Inke van der SLUIJS Ole SEEHAUSEN +1 位作者 Tom J.M.Van DOOREN Jacques J.M.van ALPHEN 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第1期57-64,共8页
Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or acceler... Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations between female preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determined by more than one gene. However, little is known about potential genetic associations between these traits. In turbid water, we found a population that is variable in male nuptial coloration from blue to yellow to red. Males at the extreme ends of the phenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species with blue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coinciding with the male phenotype distribution. For the current study, these females were mated to blue males. We measured the coloration of the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration, which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by the identity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found that mating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong genetic linkage between mating preference and the preferred trait in this population [Current Zoology 56 (1): 57-64 2010]. 展开更多
关键词 SPECIATION Sexual selection Mate choice Genetic association Cichlid fish Lake victoria
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Implications of Papyrus (<i>Cyperus papyrus</i>L.) Biomass Harvesting on Nutrient Regulation in Nyando Floodplain Wetland, Lake Victoria, Kenya 被引量:2
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作者 P. J. K. Rongoei S. T. Kariuki 《Open Journal of Ecology》 2019年第10期443-457,共15页
Harvesting of papyrus biomass plays a significant role in regulating ecosystem services of which one of them is nutrient uptake and cycling. Despite Lake Victoria’s wetlands being important, little is understood abou... Harvesting of papyrus biomass plays a significant role in regulating ecosystem services of which one of them is nutrient uptake and cycling. Despite Lake Victoria’s wetlands being important, little is understood about its role in nutrient uptake and removal. Although there have been studies done in these wetlands, there is inadequate understanding on the implication of unselective biomass harvesting on the water quality of Lake Vitoria. At the same time, these wetlands are threatened by livelihood-related pressures which are driven by extreme hydrological regimes. This study focused on Nyando floodplain wetland located in the Eastern part of the shores of Lake Victoria which is a lifeline to many rural communities living around the lake. Papyrus biomass harvesting was assessed in two study sites of Nyando wetland and at different seasons in order to determine its implication on nutrient regulating services. Participatory tools, field survey, observation, field measurements and laboratory analysis were used. Harvesting of papyrus removed 530.6 Kg N/g DM/ha/day and 97 Kg P/g DM/ha/day in Ogenya while 771.2 Kg N/g DM/ha/day and 109.2 Kg P/g DM/ha/day were removed in Wasare. However, addition of nutrients to the wetland may lead to the problem of eutrophication especially at the site where interaction of wetland and lake water occurs. Understanding the role of papyrus harvesting patterns is crucial for better planning and management of this complex resource in a changing environment. 展开更多
关键词 Papyrus BIOMASS Growth Stages NUTRIENTS Nyando WETLAND Lake victoria
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Wireless Sensor Networks for Water Quality Monitoring and Control within Lake Victoria Basin: Prototype Development 被引量:4
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作者 Anthony Faustine Aloys N. Mvuma +3 位作者 Hector J. Mongi Maria C. Gabriel Albino J. Tenge Samuel B. Kucel 《Wireless Sensor Network》 2014年第12期281-290,共10页
The need for effective and efficient monitoring, evaluation and control of water quality in Lake Victoria Basin (LVB) has become more demanding in this era of urbanization, population growth and climate change and var... The need for effective and efficient monitoring, evaluation and control of water quality in Lake Victoria Basin (LVB) has become more demanding in this era of urbanization, population growth and climate change and variability. Traditional methods that rely on collecting water samples, testing and analyses in water laboratories are not only costly but also lack capability for real-time data capture, analyses and fast dissemination of information to relevant stakeholders for making timely and informed decisions. In this paper, a Water Sensor Network (WSN) system prototype developed for water quality monitoring in LVB is presented. The development was preceded by evaluation of prevailing environment including availability of cellular network coverage at the site of operation. The system consists of an Arduino microcontroller, water quality sensors, and a wireless network connection module. It detects water temperature, dissolved oxygen, pH, and electrical conductivity in real-time and disseminates the information in graphical and tabular formats to relevant stakeholders through a web-based portal and mobile phone platforms. The experimental results show that the system has great prospect and can be used to operate in real world environment for optimum control and protection of water resources by providing key actors with relevant and timely information to facilitate quick action taking. 展开更多
关键词 Wireless SENSOR Networks LAKE victoria BASIN GATEWAY SENSOR NODES
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Influence of Land Use Activities on Spatial and Temporal Variation of Nutrient Deposition in Mwanza Region: Implication to the Atmospheric Loading to the Lake Victoria 被引量:2
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作者 Said Ali Hamad Vuai John D. Ibembe Nancy W. Mungai 《Atmospheric and Climate Sciences》 2013年第2期224-234,共11页
Increase in population growth and the associated activities have increased the nutrient input to the Lake Victoria through atmosphere and river discharge. Atmospheric input of nutrient is believed to exceed that of ri... Increase in population growth and the associated activities have increased the nutrient input to the Lake Victoria through atmosphere and river discharge. Atmospheric input of nutrient is believed to exceed that of river discharge due to relatively higher contribution of water mass to the Lake from atmosphere. However, precipitation characteristics with respect to nutrients have not been well studied to allow qualification and quantification of atmospheric contribution to the Lake Victoria. This study was conducted to investigate influence of land use activities on spatial and temporal variation of nutrient inputs from atmosphere and to estimate atmospheric loading to the Lake Victoria. The results revealed that there is significant spatial and temporal variation of nutrient deposition in the study area. High concentrations of nutrients were observed during short rains starting from September to December. This was attributed to dissolution of nutrients from soil particals and ash residues due to biomass burning accumulated in the atmosphere during dry season of June to August. Spatial variation of nutrients reflects land use activities. Urban and peri-urban areas showed very high concentration of nitrate nitrogen due to industrial and vehicle emission while rural area showed high concentration of phosphorous species and reduced forms of nitrogen species reflecting agricultural activities and animal keeping. Generally, nutrient deposition load was higher in rural area compared to urban with respective values of 15.5 and 13.9 kg·haˉ1·yˉ1 for total nitrogen and 6.1 and 2.8 kg·haˉ1·yˉ1 for total phosphorous. These results suggest that in order to realize significant reduction of nutrient input to the Lake Victoria, measures should be taken to control agricultural activities through proper land use planning. The measure may be directed to reduce biomass burning, emission from industries and vehicle as well as animal residue. 展开更多
关键词 NUTRIENT LANDUSE LAKE victoria Precipitation Atmospheric POLLUTION
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Neogene faulting and volcanism in the Victoria Land Basin of the Ross Sea, Antarctica 被引量:1
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作者 Mei Yue JinYao Gao +7 位作者 ChunFeng Li Chao Zhu XinZhi Fan Guochao Wu ZhongYan Shen Han Shi XiaoXian Cai YiDong Guo 《Earth and Planetary Physics》 EI CSCD 2022年第3期248-258,共11页
The Neogene Terror Rift in the Antarctic Victoria Land Basin(VLB)of the Ross Sea,Antarctica,is composed of the Discovery Graben and the Lee Arch.Many Neogene volcanoes are aligned in the north-south direction in the s... The Neogene Terror Rift in the Antarctic Victoria Land Basin(VLB)of the Ross Sea,Antarctica,is composed of the Discovery Graben and the Lee Arch.Many Neogene volcanoes are aligned in the north-south direction in the southern VLB,belonging to the McMurdo Volcanic Group.However,due to multiple glaciations and limited seismic data,the volcanic processes are still unclear in the northern VLB,especially in the Terror Rift.Multichannel seismic profiles were collected at the VLB from the 32nd Chinese National Antarctic Research Expedition(CHINARE).We utilized four seismic profiles from the CHINARE and additional historical profiles,along with gravity and magnetic anomalies,to analyze faults and stratigraphic characteristics in the northern Terror Rift and volcanism in the VLB.Negative flower structures found in the northern Terror Rift suggest that the Terror Rift was affected by dextral strike-slip faults extending from the northern Victoria Land(NVL).After the initial orthogonal tension,the rift transited into an oblique extension,forming a set of downward concaving normal faults and accommodation zones in the Terror Rift.On the Lee Arch,several imbricated normal faults formed and converged into a detachment fault.Under gravitational forces,the strata bent upward and formed a rollover anticline.Many deep faults and thin strata subjected to erosion facilitated volcanic activity.A brittle volcanic region in the VLB was affected by dextral strike-slip movements and east-west extension,resulting in two Neogene volcanic chains that connect three igneous provinces in the VLB:the Hallett,Melbourne,and Erebus Provinces.These two chains contain mud volcanoes with magnetic nuclei,volcanic intrusions,and late-stage volcanic eruptions.Volcanisms have brought about opposite polarities of magnetic anomalies in Antarctica,indicating the occurrence of multiple volcanic activities. 展开更多
关键词 victoria Land Basin Terror Rift seismic stratigraphy gravity and magnetic modeling FAULTING Neogene volcanic intrusion
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品牌故事:维多利亚的秘密(Victoria's Secret) 被引量:2
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《中国纤检》 2015年第16期68-69,共2页
维多利亚的秘密成立于20世纪70年代初,隶属于美国知名中高档服装生产商Intimate Brands集团。自成立那天起,公司的名字就成为了魅力、浪漫、纵容及女式内衣的代名词,公司每分钟的内衣销量高达600多件!
关键词 victoria 品牌故事 女鞋 服装生产 品牌定位 品牌命名 同步出现 斯坦福 环境保护组织 性用品
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Myanmarorchestia victoria sp. nov.(Crustacea, Amphipoda, Talitridae), a new species of landhopper from the high altitude forests in Myanmar
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作者 Ya-Mi Zheng Zhong-E Hou 《Zoological Research》 CAS CSCD 2017年第5期281-290,共10页
Myanmarorchestia victoria sp. nov. is described from high altitude habitats in Myanmar. The new species differs morphologically from its congeners by palp of maxilliped narrow; sexually dimorphic gnathopod II, propodu... Myanmarorchestia victoria sp. nov. is described from high altitude habitats in Myanmar. The new species differs morphologically from its congeners by palp of maxilliped narrow; sexually dimorphic gnathopod II, propodus of male chelate and propodus of female mitten-shaped; and dimorphic uropod II, outer ramus of male with small teeth distally, outer ramus of female with three distal spines. Analysis of DNA barcode sequences and niche distinctiveness support recognition of the new species 展开更多
关键词 Taxonomy Mt. victoria COl gene Leaflitter Morphology New species
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Ecological Devastation in Lake Victoria: Part B: Plankton and Fish Communities
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作者 Moshe Gophen 《Open Journal of Ecology》 2015年第7期315-325,共11页
A few specimens of the exotic fish, Nile Perch, (Lates niloticus, Linnaeus 1758) were transferred into Lake Victoria in early 1950’s. In early 1980’s this fish occupied the Lake Victoria ecosystem eliminating the lo... A few specimens of the exotic fish, Nile Perch, (Lates niloticus, Linnaeus 1758) were transferred into Lake Victoria in early 1950’s. In early 1980’s this fish occupied the Lake Victoria ecosystem eliminating the local endemic Haplochromines (app. 400 species). As a result of this change, together with intensification of pollution constrains from the catchment and dust deposition the ecology of Victoria’s ecosystem was modified: cyanobacteria replaced diatoms, anoxia enhanced, secchi depth became shallower, euphotic zone became thinner, fishery enhanced fully comprised of Nile Perch and Rastrineobola. The ecological significances are discussed and future propositions are presented. 展开更多
关键词 LAKE victoria NILE PERCH ECOLOGICAL Changes Fish PLANKTON
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Ecological Devastation in Lake Victoria: Part A: Thermal Structure and Anoxia
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作者 Moshe Gophen 《Open Journal of Ecology》 2015年第7期287-298,共12页
Lake Victoria is the second (excl. Caspian Sea) largest lake in the world by surface area and 7th by Volume. The lake and catchment territories are shared between three countries, Kenya, Uganda and Tanzania. A researc... Lake Victoria is the second (excl. Caspian Sea) largest lake in the world by surface area and 7th by Volume. The lake and catchment territories are shared between three countries, Kenya, Uganda and Tanzania. A research was carried out during 1990-1992 exploring the changes of the thermo-chemical structure occurred after the invasion of Nile Perch. Results of changes of physico-chemical (Temperature, DO and pH) conditions are summarized in this paper. The anoxic conditions by space and time were enhanced. Enhancement of pollutant supply from anthropogenic developments of terrestrial sources and atmospheric dust deposition accompanied by the deleterious effects of the Nile Perch invasion caused enhancement of anoxia in the lake in space and time. The combination of bottom-up nutrient supply and strong mixing conditions, expressed as low RTR values accelerate phytoplankton growth rate and production. The surplus of organic matter originated from algal biomass, enhanced anoxia. 展开更多
关键词 Lake victoria Kenya NILE PERCH ANOXIA Thermal Stability
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The Community of Parasites Infecting <i>Clarias gariepinus</i>in the Tanzanian Waters: A Case of Lake Victoria
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作者 Chacha John Mwita 《Open Journal of Ecology》 2014年第14期873-882,共10页
Quantitative variations in parasites were investigated with respect to sex and size of Clarias gariepinus, season and localities sampled. Parasitic infection in male and female fish was not significantly different;pre... Quantitative variations in parasites were investigated with respect to sex and size of Clarias gariepinus, season and localities sampled. Parasitic infection in male and female fish was not significantly different;prevalence (Man-Whitney paired sample test, U = 135.5, p = 0.7697), mean intensity (U = 136, p = 0.7829). Based on Kruskal-Wallis test analysis, the prevalence and mean intensity of five parasite species varied significantly among the three localities sampled. Adult parasites in Clarias gariepinus showed high abundance during the dry season while the larval forms showed high abundance in the wet season. In most of the parasite species analyzed the abundance varied significantly with host size. The abundance of Dolops ranarum, Paracamallanus cyatopharynx and Eumasenia bangweulensis for instance, increased with fish size, while that of Diplostomum mashonense, Tylodelphys species, Astiotrema reniferum, piscicolid leeches and Monobothrioides woodlandi increased initially but decreased as fish length reached 31 - 40 cm. Total parasite burden increased in fish of 20 - 40 cm standard length. Generally, most parasites were highly overdispersed and the negative binomial model described their distribution. 展开更多
关键词 Population BIOLOGY Parasites Clarias gariepinus LAKE victoria Tanzania
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The link between the Victoria mode in the preceding boreal winter and spring precipitation over the southeastern USA and Gulf of Mexico
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作者 PU Xiu-Shu CHEN Quan-Liang +1 位作者 DING Rui-Qiang GUO Yi-Peng 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第4期285-291,共7页
The sea surface temperature anomalies (SSTAs) associated with the Victoria mode (VM) can persist into the following season and then influence climate variability in the tropical Pacific. This paper demonstrates th... The sea surface temperature anomalies (SSTAs) associated with the Victoria mode (VM) can persist into the following season and then influence climate variability in the tropical Pacific. This paper demonstrates the connection between the preceding boreal winter VM and precipitation in the following spring over the southeastern United States (SE USA) and the Gulf of Mexico (GM). The results indicate that a positive (negative) preceding winter VM is usually followed by increased (reduced) precipitation over the SE USA and GM during the following spring. The corresponding mechanism is similar, but slightly different to, the seasonal footprinting mechanism. For positive VM cases, the preceding-winter VM-related SSTAs appear to persist into the following spring via air- sea interactions, which then induce low-level convergence and vigorous ascending motion, leading to an adjustment of the zonal and meridional circulation. This adjustment can then influence the local Hadley cell by weakening the downward branch. These anomalous patterns of vertical airflow enhance spring precipitation over the SE USA and GM under suitable moisture conditions. Hence, this work demonstrates that the preceding-winter VM has the potential to regulate precipitation over the SE USA and GM in the following spring. 展开更多
关键词 victoria mode springprecipitation southeasternUSA Gulf of Mexico air-seainteraction
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Morphometric Relationships among the Clariid Fishes of the Lake Victoria Basin, Tanzania
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作者 Chacha John Mwita 《Open Journal of Marine Science》 2015年第1期26-32,共7页
Six hundred and fifty-eight specimens of the Clariidae were collected from seven localities in the Lake Victoria basin and the Malagarasi wetland, Tanzania. A total of three hundred unadjusted morphometric measurement... Six hundred and fifty-eight specimens of the Clariidae were collected from seven localities in the Lake Victoria basin and the Malagarasi wetland, Tanzania. A total of three hundred unadjusted morphometric measurements and meristic counts were analysed with the aim of assessing the adequacy of morphometric technique to delineate the clariid species occurring in theLake Victoriabasin. Results showed that morphometrics augmented by multivariate analysis (PCA, DCA and cluster analysis) amalgamated the clariid fishes into three groups, the?Clarias alluaudi/C. werneri,?C. gariepinus/C. liocephalus?andClariallabes petricola. Although other workers have used this technique, the present study concluded that, standing alone morphometrics is not a substitute for external morphology in the identification of clariid fish species, as it failed to separate the clariids into their respective taxonomic species. The technique, however, insinuates the regressional morphological relationships among the clariids occurring in the Lake Victoria basin. 展开更多
关键词 Morphology Regression Clariids LAKE victoria
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Interdecadal change in the lagged relationship between the Victoria mode and ENSO
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作者 XIE Wei FAN Guangzhou +4 位作者 DING Ruiqiang LI Jianping LI Baosheng QIN Jianhuang ZHOU Xuejing 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第4期294-301,共8页
This paper investigates the interdecadal variability in the lagged relationship between the spring Victoria mode(VM)and the following-winter El Ni?o–Southern Oscillation(ENSO).It is found that the relationship is str... This paper investigates the interdecadal variability in the lagged relationship between the spring Victoria mode(VM)and the following-winter El Ni?o–Southern Oscillation(ENSO).It is found that the relationship is strong during high correlation(HC)periods,e.g.1957–1964 and 1981–2004,but weak during low correlation(LC)periods,e.g.1907–1924,1926–1956,1965–1980,and2005–2008.The surface air–sea coupling and the evolution of subsurface ocean temperature anomaliesh along the equatorial Paci?c associated with the VM are found to be strong during HC periods and weak during LC periods,which results in a stronger impact of the VM on the following-winter ENSO during HC periods.The interdecadal change in the relationship between the VM and ENSO is mainly due to the interdecadal change in the intensity of the VM,which is found to be in?uenced by the North Paci?c Oscillation.Our?ndings may improve the prediction skill for the onset of ENSO events. 展开更多
关键词 victoria mode ENSO interdecadal change North Pacific Oscillation
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