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First observation of Karlodinium venef icum from the East China Sea and the coastal waters of Germany

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Acta Oceanologica Sinica 2011年第6期30卷 112-121页

作者： WANG Hongxia LU Douding HUANG Haiyan GOBEL Jeaaette DAI Xinfeng XIA Ping State Key Laboratory of Satellite Ocean Environment Dynamics the Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Landesamt fiir Landwirtschaft Umwelt und landliche Raume Flintbek 24220 Germany

Harmful algal blooms often occurred in the East China Sea （ECS） and the German coastal waters of the North Sea but Karlodinium veneficum had not been taxonomically reported. Two strains of Karlodinium （LAMB090611 and LAMB010601） were isolated from the two areas in 2009. The morphological characteristics and molecular phylogeny of two strains are compared on the basis of observation of a light microscope, a scanning electron microscope （SEM）, a laser scanning micro-scope （LSM） and an internal transcribed spacer （ITS） sequence data. The mean cell length of strain LAMB090611 is （14.2 ± 1.8） μm （range 11.1–18.7 μm） and mean width is （10.8 ± 1.5） μm （range 8.2– 14.7 μm）. The mean cell length of strain LAMB010601 is （15.1 ± 1.2） μm （range 12.7–17.9 μm） and the mean width is （11.4 ± 1.1） μm （range 9.1–14.7 μm）, respectively. The two strains are similar in morphological characteristics, including a straight apical groove, distinct ventral pore, sulcal extension, cingulum displacement, two or four irregular shaped chloroplasts within the cell and almost equal sized epicone and hypocone. The large and round nucleus is located at the center or at the hypocone of the cell. The sequence length of the ECS strain LAMB090611 and the German strain LAMB010601 is 640 and 646 bp, respectively. The GC content is 49%. The nucleotide similarity of the two strains is 98.1%. The sequence divergence is 0.003. Both strains are confirmed as Karlo-dinium veneficum （D. Ballantine） J. Larsen and this is the first taxonomic report from China and Germany coastal waters. The population dynamics of this toxic species in the ECS and German coastal waters needs to be investigated in the near future.

关键词： Karlodinium veneficum East China Sea morphological characteristic scanning electron microscope internal transcribed spacer phylogeny

The Environmental Functions and Ecological Effects of Organic Carbon in Silt

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Journal of Earth Science 2020年第4期31卷 834-844页

作者： Rui Liu Teng Ma Wenkai Qiu Ziqi Peng Chenxuan Shi School of Earth Sciences China University of GeosciencesWuhan 430074China State Key Laboratory of Biogeology and Environmenta Geology China University of GeosciencesWuhan 430074China

Silt is a kind of unconsolidated sediment consisting of fine particles;silt is generally deposited across wide areas on the surfaces of drainages and in oceans under static or slow-hydrodynamic conditions. The organic carbon(OC) in silt has multiple essential environmental functions. This paper elaborates the morphological and environmental indication functions of OC in silt, and the effect of its own migration and transformation on environmental deterioration. Organic carbon exists in silt in two forms, free and mineral-binding. Meanwhile, based on its formation and structure, OC can be divided into light and heavy fraction of OC. Environmental information including data related to paleoclimates, ancient levels of productivity level, and variations in regional organism abundance can be discovered from total organic carbon, the C/N ratio, and OC isotope content. Degradation of OC is believed to participate in the emission of greenhouse gases, release of heavy metals and other contaminants. Finally, from the view of silt deposition, the possible influence of complex water-rock interaction in which OC is involved during the evolution of silt to a clayey aquitard on the hydrochemical composition of groundwater is discussed, which provides a new perspective for future research on the carbon cycle in nature.

关键词： silt organic carbon morphological characteristic environmental indication environmental effect

Acclimation and Tolerance Strategies of Rice under Drought Stress

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Rice science 2015年第4期22卷 147-161页

作者： Veena PANDEY Alok SHUKLA Department of Plant Physiology College of Basic Sciences and HumanitiesGovind Ballabh Pant University of Agriculture & Technology

Rice （Oryza sativa L.） is an important food crop and requires larger amount of water throughout its life cycle as compared to other crops. Hence, water related stress cause severe threat to rice production. Drought is a major challenge limiting rice production. It affects rice at morphological （reduced germination, plant height, plant biomass, number of tillers, various root and leaf traits）, physiological （reduced photosynthesis, transpiration, stomatal conductance, water use efficiency, relative water content, chlorophyll content, photosystem II activity, membrane stability, carbon isotope discrimination and abscisic acid content）, biochemical （accumulation of osmoprotectant like proline, sugars, polyamines and antioxidants） and molecular （altered expression of genes which encode transcription factors and defence related proteins） levels and thereby affects its yield. To facilitate the selection or development of drought tolerant rice varieties, a thorough understanding of the various mechanisms that govern the yield of rice under water stress condition is a prerequisite. Thus, this review is focused mainly on recent information about the effects of drought on rice, rice responses as well as adaptation mechanisms to drought stress.

关键词： rice water drought stress yield attribute morphological characteristic physiological characteristic biochemical characteristic molecular level

morphological Phylogeny of the Water Snake Subfamily Homalopsinae (Serpent: Colubridae)

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Zoological Research 2006年第4期27卷 363-366页

作者：吕顺清庞峻锋杨大同黄山学院生物多样性研究所中国科学院昆明动物研究所云南昆明650223 中国科学院昆明动物研究所

The morphological phylogeny of the water snake subfamily Homalopsinae, containing 10 genera, of which seven are monotypic, was not reported up until now. Here fourteen morphological characters were selected for the cladistic analysis. Using software Hennig 86, two phylogenetic trees were inferred and the results showed that the subfamily Homalopsinae was divided into two groups. Compared with the molecular phylonenetic tree of Voris et al （2002）, the genera Gerarda and Fordonia are sister groups in both studies; both studies also yielded the same monophyletic lineage, which contained three genera （Cerberus ＋ Erpeton ＋ Homalopsis ）. However, the position of the genus Cantoria is distinctly different with the study of Voris et a1（2002）.

关键词： Homalopsinae Cladistic analysis morphological characteristic

Review on the proceeding of automatic seedlings classification by computer vision

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Journal of Forestry Research 2002年第3期13卷 245-249,252页

作者：杨延竹赵学增王伟杰吴羡哈尔滨工业大学哈尔滨150001

The classification of seedlings is important to ensure the viability of seedlings after transplantation and is acknowledged as a key factor in forestation and environmental improvement. Based on numerous papers on automatic seedling classification (ASC), the seedling grading theory, traditional grading methods, the background and the proceeding of ASC techniques are described. The automation of the measurement of seedling morphological characteristics by photoelectric meters and computer vision is studied, and the automatic methods of the current grading systems are described respectively. And the further researches on ASC by computer vision are proposed.

关键词： Seedlings classification Automation morphological characteristic Computer vision

Research Progress on Water Use Efficiency and Drought Resistance of Turfgrass

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Journal of Northeast Agricultural University(English Edition) 2013年第1期20卷 85-90页

作者： Li Xin Yan Qing-wei Zhang Lu Liu Hui-min Zheng Hai-xia Bao Wen-long Chen Ya-jun College of Horticulture Northeast Agricultural University

Improving turfgrass drought resistance and save-water features are very important to solve water deficiency in turfgrass production and management. This research did some surveys of systematic literature review about turfgrass drought tolerance morphological characteristics, physiological characteristics and water use efficiency, and provided the detailed information for enhancing turfgrass drought resistant and water use efficiency in the future.

关键词： water use efficiency turf drought resistance morphological characteristic physiological characteristic

Effects of Row-Spacing on Canopy Structure and Yield in Different Plant Type Rice Cultivars

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Journal of Northeast Agricultural University(English Edition) 2012年第4期19卷 11-19页

作者： Zhao Hai-xin Wang Xiao-xue Guo Zhen-hua Huang Xiao-qun Liu Hua-long Rice Research Institute Shenyang Agricultural University Rice Research Institute Heilongjiang Academy of Agricultural Sciences College of Agriculture Northeast Agricultural University

Two japonica rice varieties, Longjing 20 （more tillers and curved panicle type, MCP） and Longjing 21 （few tillers and half erect panicle type, FEP）, were used to study the effects of row-spacing on canopy structure, morphological characteristics and yield. The results showed that the percentage of productive tiller reduced first, and increased afterwards as row-spacing increasing. The relationship between row spacing and the percentage of productive tiller fitted a quadratic regression. The effects of row spacing on leaf area index （LAI） at later tillering stage and the highest stem number per square meter also followed a quadratic regression relationship with increasing first and then reducing. The effects of row-spacing on primary branch were larger than the secondary branch in Longjing 20. However, the trend in Longjing 21 was opposite. The relationship between row spacing and seed setting rate of the secondary branch or panicle was negatively correlated. An extreme significant negative correlation was obtained between seed setting rate of secondary branch in Longjing 20. There was no significant positive correlation between row-spacing and yield in Longjing 20 （R2=0.68）. However, the negative correlation between row-spacing and yield of Longjing 21 was extremely significant （R2=–0.96＊＊）. The canopy structure of MCP was more sensitive to row-spacing. The positive correlation between row spacing and the length of the flag leaf （R2=0.89＊＊）, the width of the flag leaf （R2=0.85＊）, the length of the last internode （R2=0.85＊）, the length of the last 2nd internode （R2=0.96＊＊） or the length of the panicle （R2=0.91＊＊） was significant or extremely significant in Longjing 20, but not in Longjing 21. The wider row-spacing promoted the accumulation of the dry matter of panicle, stem and leaf and the yield formation in MCP. The best row-spacing in Longjing 20 was 30 cm. For Longjing 21, the narrower row-spacing was better. The best row-spacing of it was 21 cm. These results su

关键词： row-spacing more tillers and curved panicle type (MCP) few tillers and half erect panicle type (FEP) canopy structure morphological characteristic yield

morphological Difference and Karyotype of Pelteobagrus fulvidraco in Dongting Lake Water System

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Agricultural Science & Technology 2011年第10期12卷 1521-1524页

作者：刘良国邹万生杨春英罗玉双杨品红湖南文理学院生命科学学院动物学湖南省高校重点实验室湖南常德415000

[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchicine injection method in vivo,the morphological characteristics and karyotype of *** in Yuanshui River and Lishui River of Dongting Lake were analyzed.[Result] In three ratio traits including standard length/head length,standard length/caudal peduncle depth,head length/snout length,*** of Yuanshui River and Lishui River had significant differences（P0.05）.However,the number and karyotype of their chromosomes were *** chromosome number was 2n = 52,and the karyotype formula was 20M＋12SM＋10ST＋*** number of chromosome arm was 84.[Conclusion] The research result had certain theoretical guidance significance for the protection and utilization of wild *** in Dongting Lake water system.

关键词： Dongting Lake water system Yuanshui River and Lishui River P.fulvidraco morphological characteristic Karyotype

Description of Natural Enemies of Pasture Pest-Carabdae Insects

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Plant Diseases and Pests 2010年第2期1卷 41-44页

作者：赵同贵吴彤林莫熙礼邓伟黔西南民族职业技术学院贵州兴义562400

The investigation result of grassland predators Carabidae in southwest of Guizhou was reported. Taxonomic status, morphological characteristics of 5 genera and 13 species of insect predators were described, their livi... 详细信息

关键词： Southwest of Guizhou morphological characteristic Insect Description of species