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11.
记述了裂脖跳小蜂属1新种--韩氏裂脖跳小蜂(Rhopus hanni Zu&Li, sp. nov.),1中国新记录种--硫磺裂脖跳小蜂(Rhopus sulphureus(Westwood,1837))。对新种及新记录种的形态特征和分布进行了详细的描述,并附有成虫特征照片。 相似文献
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长白山北坡访花昆虫研究(Ⅰ)——吉林省访花食蚜蝇科昆虫23新记录种 总被引:1,自引:0,他引:1
2004—2005年对长白山北坡访花食蚜蝇进行了调查。结果表明:该地区的访花食蚜蝇科昆虫约有50种,其中有23种为吉林省新记录种,隶属于2亚科15属。 相似文献
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鲇形目,鳞科的长须黄颡鱼Pelteobagrus eupogon在广西桂林漓江首次发现,为珠江水系新记录。采集标本1尾,全长254.78mm,标准体长207.70mm,背鳍Ⅱ-6,胸鳍Ⅱ-6,腹鳍i-5,臀鳍19,外部第一鳃弓鳃耙数16;标准体长为体高的9.32倍,为头长的6.46倍,头长为吻长的3.96倍,为眼径的4.21倍,眼间距的2.25倍,尾柄长为尾柄高的3.09倍。 相似文献
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Background, Aim and Scope The distribution of sediments in estuarine beaches is controlled by the interactions between sediment supply, hydrodynamic
processes and human intervention. The main purpose of this study is to characterize the sediments of Tagus estuarine beaches
in order to understand their origin and to contribute to a better knowledge of the Tagus estuary sediment budget.
Methods Surface sediment samples were collected across beach profiles and sand grain size analysis was performed by dry sieving. Grain
size statistics for the median (d50) and standard deviation (SDM) were obtained using the Moment method. This study was complemented by a qualitative evaluation
of the sediment composition. Cross-shore topographic surveys were conducted for selected sampling sites.
Results Tagus estuarine beach sediments are mainly composed of quartz sand particles which are fine-grained and well sorted near the
mouth of the estuary and medium to coarse-grained and moderately sorted in the inner domain. Compositional results show evidence
of active anthropogenic sediment sources, especially in the coarser fractions.
Discussion The analysis of the textural and compositional characteristics of beach sediments in the inner estuarine domain is compatible
with local sedimentary sources, while a marine signature is present at the mouth and inlet channel sediments. In the inner
domain, differences in the sedimentary processes are represented by the textural characteristics of the sediments, such as
the sorting degree and the gravel content. Sediment characteristics also reflect human intervention in the system, with the
introduction of anthropogenic and allochthonous particles and the mixture of sediments from different sources.
Conclusions The sediments of the inner Tagus estuarine beaches are derived from local Plio-Pleistocene outcrops while inlet and outer
estuary beaches reveal a dominant marine source. Beach textural variability observed in the inner domain is not related to
wave forcing gradients, but mainly to variations in the sedimentary processes along the estuarine margins and to human intervention.
Results show that the Tagus estuarine beaches depended, almost exclusively, on sediment input from local sources until the
last century. With increasing human occupation, sediment transfers became dominated by anthropogenically related activities
mainly connected with the occupation of estuarine margins and dredging.
Recommendations and Perspectives Further studies should extend the present level of knowledge in what concerns sand transport patterns through additional compositional
and geochemical analysis, and the development of new techniques in order to allow the quantitative evaluation of the impact
of human activities on the sediment budget. 相似文献
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农产品视频履历追溯系统设计 总被引:1,自引:0,他引:1
针对目前农产品追溯系统中履历信息单一化和信息量少的问题,设计了一个以实现生产过程中质量追溯为目的的农产品视频履历追溯系统.基于ARM9嵌入式技术与H.264压缩技术相结合对农产品生产过程进行视频履历的采集和压缩处理,应用3G无线传输技术对视频履历进行传输,通过生产服务器对视频履历进行存储,以.NET为平台开发了用户对农产品视频履历追溯系统的软件.该系统可采集农产品生产过程各个阶段的视频履历,为农产品追溯提供了更直观、更丰富、更具说服力的履历信息.该系统运行结果表明,系统具有通用性强、可靠性高、稳定性好、便携式等特点,可方便地应用于温室、农田等各种农产品生产的环境,从而满足用户的不同需求. 相似文献
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本文报道我国葡萄孢属(Botrvtis)的三个国内新记录种,即大蒜盲种葡萄孢B.Porri,葱鳞葡萄B.squamosa和球精葡萄孢B.sphaerosperma,每种均有描述和附图,标本及菌株保存于云南农业大学植病研究室真菌标本室(MHYAU). 相似文献